one-elf | ELF reader in Java

by odnoklassniki Java Version: Current License: Apache-2.0

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kandi X-RAY | one-elf Summary

one-elf is a Java library. one-elf has no bugs, it has no vulnerabilities, it has a Permissive License and it has low support. However one-elf build file is not available. You can download it from GitHub.

ELF reader in Java.

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Quality

Security

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kandi-support Support

one-elf has a low active ecosystem.
It has 15 star(s) with 5 fork(s). There are 12 watchers for this library.
It had no major release in the last 12 months.
There are 0 open issues and 1 have been closed. There are 1 open pull requests and 0 closed requests.
It has a neutral sentiment in the developer community.
The latest version of one-elf is current.

one-elf Support

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one-elf Support

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quality kandi Quality

one-elf has 0 bugs and 0 code smells.

one-elf Quality

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one-elf Quality

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Average in #Java

security Security

one-elf has no vulnerabilities reported, and its dependent libraries have no vulnerabilities reported.
one-elf code analysis shows 0 unresolved vulnerabilities.
There are 0 security hotspots that need review.

one-elf Security

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one-elf Security

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license License

one-elf is licensed under the Apache-2.0 License. This license is Permissive.
Permissive licenses have the least restrictions, and you can use them in most projects.

one-elf License

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one-elf License

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build Reuse

one-elf releases are not available. You will need to build from source code and install.
one-elf has no build file. You will be need to create the build yourself to build the component from source.
one-elf saves you 377 person hours of effort in developing the same functionality from scratch.
It has 899 lines of code, 97 functions and 16 files.
It has medium code complexity. Code complexity directly impacts maintainability of the code.

one-elf Reuse

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one-elf Reuse

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Top functions reviewed by kandi - BETA

kandi has reviewed one-elf and discovered the below as its top functions. This is intended to give you an instant insight into one-elf implemented functionality, and help decide if they suit your requirements.

Returns an iterator over all of the symbols in this set .

Reads a subsection .

Read directory types .

Reads a string from the buffer .

Gets a specific section with the given name .

Get the relocations .

Returns a string representation of this virtual address .

Returns true if the address is empty .

The long value

Gets the addendend .

Get all kandi verified functions for this library.

one-elf Key Features

ELF reader in Java

one-elf Examples and Code Snippets

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How do I really disable all rustc optimizations?

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cargo rustc -- --emit mir

fn _start() -> ! {
    let mut _0: !;                       // return place in scope 0 at src\main.rs:5:31: 5:32
    let _1: u64;                         // in scope 0 at src\main.rs:6:9: 6:10
    scope 1 {
        debug a => _1;                   // in scope 1 at src\main.rs:6:9: 6:10
        let _2: u64;                     // in scope 1 at src\main.rs:7:9: 7:10
        scope 2 {
            debug b => _2;               // in scope 2 at src\main.rs:7:9: 7:10
            let _3: u64;                 // in scope 2 at src\main.rs:8:9: 8:10
            scope 3 {
                debug c => _3;           // in scope 3 at src\main.rs:8:9: 8:10
            }
        }
    }

    bb0: {
        _1 = const 4_u64;                // scope 0 at src\main.rs:6:18: 6:19
        _2 = const 7_u64;                // scope 1 at src\main.rs:7:18: 7:19
        _3 = const 28_u64;               // scope 2 at src\main.rs:8:18: 8:23
        goto -> bb1;                     // scope 3 at src\main.rs:10:5: 10:12
    }

    bb1: {
        goto -> bb1;                     // scope 3 at src\main.rs:10:5: 10:12
    }
}

cargo rustc -- -Z mir-opt-level=0 --emir mir

fn _start() -> ! {
    let mut _0: !;                       // return place in scope 0 at src\main.rs:5:31: 5:32
    let mut _1: !;                       // in scope 0 at src\main.rs:5:33: 11:2
    let _2: u64;                         // in scope 0 at src\main.rs:6:9: 6:10
    let mut _5: u64;                     // in scope 0 at src\main.rs:8:18: 8:19
    let mut _6: u64;                     // in scope 0 at src\main.rs:8:22: 8:23
    let mut _7: (u64, bool);             // in scope 0 at src\main.rs:8:18: 8:23
    let mut _8: !;                       // in scope 0 at src\main.rs:10:5: 10:12
    let mut _9: ();                      // in scope 0 at src\main.rs:5:1: 11:2
    scope 1 {
        debug a => _2;                   // in scope 1 at src\main.rs:6:9: 6:10
        let _3: u64;                     // in scope 1 at src\main.rs:7:9: 7:10
        scope 2 {
            debug b => _3;               // in scope 2 at src\main.rs:7:9: 7:10
            let _4: u64;                 // in scope 2 at src\main.rs:8:9: 8:10
            scope 3 {
                debug c => _4;           // in scope 3 at src\main.rs:8:9: 8:10
            }
        }
    }

    bb0: {
        StorageLive(_1);                 // scope 0 at src\main.rs:5:33: 11:2
        StorageLive(_2);                 // scope 0 at src\main.rs:6:9: 6:10
        _2 = const 4_u64;                // scope 0 at src\main.rs:6:18: 6:19
        StorageLive(_3);                 // scope 1 at src\main.rs:7:9: 7:10
        _3 = const 7_u64;                // scope 1 at src\main.rs:7:18: 7:19
        StorageLive(_4);                 // scope 2 at src\main.rs:8:9: 8:10
        StorageLive(_5);                 // scope 2 at src\main.rs:8:18: 8:19
        _5 = _2;                         // scope 2 at src\main.rs:8:18: 8:19
        StorageLive(_6);                 // scope 2 at src\main.rs:8:22: 8:23
        _6 = _3;                         // scope 2 at src\main.rs:8:22: 8:23
        _7 = CheckedMul(_5, _6);         // scope 2 at src\main.rs:8:18: 8:23
        assert(!move (_7.1: bool), "attempt to compute `{} * {}`, which would overflow", move _5, move _6) -> bb1; // scope 2 at src\main.rs:8:18: 8:23
    }

    bb1: {
        _4 = move (_7.0: u64);           // scope 2 at src\main.rs:8:18: 8:23
        StorageDead(_6);                 // scope 2 at src\main.rs:8:22: 8:23
        StorageDead(_5);                 // scope 2 at src\main.rs:8:22: 8:23
        StorageLive(_8);                 // scope 3 at src\main.rs:10:5: 10:12
        goto -> bb2;                     // scope 3 at src\main.rs:10:5: 10:12
    }

    bb2: {
        _9 = const ();                   // scope 3 at src\main.rs:10:10: 10:12
        goto -> bb2;                     // scope 3 at src\main.rs:10:5: 10:12
    }
}

cargo rustc -- --emit mir

fn _start() -> ! {
    let mut _0: !;                       // return place in scope 0 at src\main.rs:5:31: 5:32
    let _1: u64;                         // in scope 0 at src\main.rs:6:9: 6:10
    scope 1 {
        debug a => _1;                   // in scope 1 at src\main.rs:6:9: 6:10
        let _2: u64;                     // in scope 1 at src\main.rs:7:9: 7:10
        scope 2 {
            debug b => _2;               // in scope 2 at src\main.rs:7:9: 7:10
            let _3: u64;                 // in scope 2 at src\main.rs:8:9: 8:10
            scope 3 {
                debug c => _3;           // in scope 3 at src\main.rs:8:9: 8:10
            }
        }
    }

    bb0: {
        _1 = const 4_u64;                // scope 0 at src\main.rs:6:18: 6:19
        _2 = const 7_u64;                // scope 1 at src\main.rs:7:18: 7:19
        _3 = const 28_u64;               // scope 2 at src\main.rs:8:18: 8:23
        goto -> bb1;                     // scope 3 at src\main.rs:10:5: 10:12
    }

    bb1: {
        goto -> bb1;                     // scope 3 at src\main.rs:10:5: 10:12
    }
}

cargo rustc -- -Z mir-opt-level=0 --emir mir

fn _start() -> ! {
    let mut _0: !;                       // return place in scope 0 at src\main.rs:5:31: 5:32
    let mut _1: !;                       // in scope 0 at src\main.rs:5:33: 11:2
    let _2: u64;                         // in scope 0 at src\main.rs:6:9: 6:10
    let mut _5: u64;                     // in scope 0 at src\main.rs:8:18: 8:19
    let mut _6: u64;                     // in scope 0 at src\main.rs:8:22: 8:23
    let mut _7: (u64, bool);             // in scope 0 at src\main.rs:8:18: 8:23
    let mut _8: !;                       // in scope 0 at src\main.rs:10:5: 10:12
    let mut _9: ();                      // in scope 0 at src\main.rs:5:1: 11:2
    scope 1 {
        debug a => _2;                   // in scope 1 at src\main.rs:6:9: 6:10
        let _3: u64;                     // in scope 1 at src\main.rs:7:9: 7:10
        scope 2 {
            debug b => _3;               // in scope 2 at src\main.rs:7:9: 7:10
            let _4: u64;                 // in scope 2 at src\main.rs:8:9: 8:10
            scope 3 {
                debug c => _4;           // in scope 3 at src\main.rs:8:9: 8:10
            }
        }
    }

    bb0: {
        StorageLive(_1);                 // scope 0 at src\main.rs:5:33: 11:2
        StorageLive(_2);                 // scope 0 at src\main.rs:6:9: 6:10
        _2 = const 4_u64;                // scope 0 at src\main.rs:6:18: 6:19
        StorageLive(_3);                 // scope 1 at src\main.rs:7:9: 7:10
        _3 = const 7_u64;                // scope 1 at src\main.rs:7:18: 7:19
        StorageLive(_4);                 // scope 2 at src\main.rs:8:9: 8:10
        StorageLive(_5);                 // scope 2 at src\main.rs:8:18: 8:19
        _5 = _2;                         // scope 2 at src\main.rs:8:18: 8:19
        StorageLive(_6);                 // scope 2 at src\main.rs:8:22: 8:23
        _6 = _3;                         // scope 2 at src\main.rs:8:22: 8:23
        _7 = CheckedMul(_5, _6);         // scope 2 at src\main.rs:8:18: 8:23
        assert(!move (_7.1: bool), "attempt to compute `{} * {}`, which would overflow", move _5, move _6) -> bb1; // scope 2 at src\main.rs:8:18: 8:23
    }

    bb1: {
        _4 = move (_7.0: u64);           // scope 2 at src\main.rs:8:18: 8:23
        StorageDead(_6);                 // scope 2 at src\main.rs:8:22: 8:23
        StorageDead(_5);                 // scope 2 at src\main.rs:8:22: 8:23
        StorageLive(_8);                 // scope 3 at src\main.rs:10:5: 10:12
        goto -> bb2;                     // scope 3 at src\main.rs:10:5: 10:12
    }

    bb2: {
        _9 = const ();                   // scope 3 at src\main.rs:10:10: 10:12
        goto -> bb2;                     // scope 3 at src\main.rs:10:5: 10:12
    }
}

cargo rustc -- --emit mir

fn _start() -> ! {
    let mut _0: !;                       // return place in scope 0 at src\main.rs:5:31: 5:32
    let _1: u64;                         // in scope 0 at src\main.rs:6:9: 6:10
    scope 1 {
        debug a => _1;                   // in scope 1 at src\main.rs:6:9: 6:10
        let _2: u64;                     // in scope 1 at src\main.rs:7:9: 7:10
        scope 2 {
            debug b => _2;               // in scope 2 at src\main.rs:7:9: 7:10
            let _3: u64;                 // in scope 2 at src\main.rs:8:9: 8:10
            scope 3 {
                debug c => _3;           // in scope 3 at src\main.rs:8:9: 8:10
            }
        }
    }

    bb0: {
        _1 = const 4_u64;                // scope 0 at src\main.rs:6:18: 6:19
        _2 = const 7_u64;                // scope 1 at src\main.rs:7:18: 7:19
        _3 = const 28_u64;               // scope 2 at src\main.rs:8:18: 8:23
        goto -> bb1;                     // scope 3 at src\main.rs:10:5: 10:12
    }

    bb1: {
        goto -> bb1;                     // scope 3 at src\main.rs:10:5: 10:12
    }
}

cargo rustc -- -Z mir-opt-level=0 --emir mir

fn _start() -> ! {
    let mut _0: !;                       // return place in scope 0 at src\main.rs:5:31: 5:32
    let mut _1: !;                       // in scope 0 at src\main.rs:5:33: 11:2
    let _2: u64;                         // in scope 0 at src\main.rs:6:9: 6:10
    let mut _5: u64;                     // in scope 0 at src\main.rs:8:18: 8:19
    let mut _6: u64;                     // in scope 0 at src\main.rs:8:22: 8:23
    let mut _7: (u64, bool);             // in scope 0 at src\main.rs:8:18: 8:23
    let mut _8: !;                       // in scope 0 at src\main.rs:10:5: 10:12
    let mut _9: ();                      // in scope 0 at src\main.rs:5:1: 11:2
    scope 1 {
        debug a => _2;                   // in scope 1 at src\main.rs:6:9: 6:10
        let _3: u64;                     // in scope 1 at src\main.rs:7:9: 7:10
        scope 2 {
            debug b => _3;               // in scope 2 at src\main.rs:7:9: 7:10
            let _4: u64;                 // in scope 2 at src\main.rs:8:9: 8:10
            scope 3 {
                debug c => _4;           // in scope 3 at src\main.rs:8:9: 8:10
            }
        }
    }

    bb0: {
        StorageLive(_1);                 // scope 0 at src\main.rs:5:33: 11:2
        StorageLive(_2);                 // scope 0 at src\main.rs:6:9: 6:10
        _2 = const 4_u64;                // scope 0 at src\main.rs:6:18: 6:19
        StorageLive(_3);                 // scope 1 at src\main.rs:7:9: 7:10
        _3 = const 7_u64;                // scope 1 at src\main.rs:7:18: 7:19
        StorageLive(_4);                 // scope 2 at src\main.rs:8:9: 8:10
        StorageLive(_5);                 // scope 2 at src\main.rs:8:18: 8:19
        _5 = _2;                         // scope 2 at src\main.rs:8:18: 8:19
        StorageLive(_6);                 // scope 2 at src\main.rs:8:22: 8:23
        _6 = _3;                         // scope 2 at src\main.rs:8:22: 8:23
        _7 = CheckedMul(_5, _6);         // scope 2 at src\main.rs:8:18: 8:23
        assert(!move (_7.1: bool), "attempt to compute `{} * {}`, which would overflow", move _5, move _6) -> bb1; // scope 2 at src\main.rs:8:18: 8:23
    }

    bb1: {
        _4 = move (_7.0: u64);           // scope 2 at src\main.rs:8:18: 8:23
        StorageDead(_6);                 // scope 2 at src\main.rs:8:22: 8:23
        StorageDead(_5);                 // scope 2 at src\main.rs:8:22: 8:23
        StorageLive(_8);                 // scope 3 at src\main.rs:10:5: 10:12
        goto -> bb2;                     // scope 3 at src\main.rs:10:5: 10:12
    }

    bb2: {
        _9 = const ();                   // scope 3 at src\main.rs:10:10: 10:12
        goto -> bb2;                     // scope 3 at src\main.rs:10:5: 10:12
    }
}

cargo rustc -- --emit mir

fn _start() -> ! {
    let mut _0: !;                       // return place in scope 0 at src\main.rs:5:31: 5:32
    let _1: u64;                         // in scope 0 at src\main.rs:6:9: 6:10
    scope 1 {
        debug a => _1;                   // in scope 1 at src\main.rs:6:9: 6:10
        let _2: u64;                     // in scope 1 at src\main.rs:7:9: 7:10
        scope 2 {
            debug b => _2;               // in scope 2 at src\main.rs:7:9: 7:10
            let _3: u64;                 // in scope 2 at src\main.rs:8:9: 8:10
            scope 3 {
                debug c => _3;           // in scope 3 at src\main.rs:8:9: 8:10
            }
        }
    }

    bb0: {
        _1 = const 4_u64;                // scope 0 at src\main.rs:6:18: 6:19
        _2 = const 7_u64;                // scope 1 at src\main.rs:7:18: 7:19
        _3 = const 28_u64;               // scope 2 at src\main.rs:8:18: 8:23
        goto -> bb1;                     // scope 3 at src\main.rs:10:5: 10:12
    }

    bb1: {
        goto -> bb1;                     // scope 3 at src\main.rs:10:5: 10:12
    }
}

cargo rustc -- -Z mir-opt-level=0 --emir mir

fn _start() -> ! {
    let mut _0: !;                       // return place in scope 0 at src\main.rs:5:31: 5:32
    let mut _1: !;                       // in scope 0 at src\main.rs:5:33: 11:2
    let _2: u64;                         // in scope 0 at src\main.rs:6:9: 6:10
    let mut _5: u64;                     // in scope 0 at src\main.rs:8:18: 8:19
    let mut _6: u64;                     // in scope 0 at src\main.rs:8:22: 8:23
    let mut _7: (u64, bool);             // in scope 0 at src\main.rs:8:18: 8:23
    let mut _8: !;                       // in scope 0 at src\main.rs:10:5: 10:12
    let mut _9: ();                      // in scope 0 at src\main.rs:5:1: 11:2
    scope 1 {
        debug a => _2;                   // in scope 1 at src\main.rs:6:9: 6:10
        let _3: u64;                     // in scope 1 at src\main.rs:7:9: 7:10
        scope 2 {
            debug b => _3;               // in scope 2 at src\main.rs:7:9: 7:10
            let _4: u64;                 // in scope 2 at src\main.rs:8:9: 8:10
            scope 3 {
                debug c => _4;           // in scope 3 at src\main.rs:8:9: 8:10
            }
        }
    }

    bb0: {
        StorageLive(_1);                 // scope 0 at src\main.rs:5:33: 11:2
        StorageLive(_2);                 // scope 0 at src\main.rs:6:9: 6:10
        _2 = const 4_u64;                // scope 0 at src\main.rs:6:18: 6:19
        StorageLive(_3);                 // scope 1 at src\main.rs:7:9: 7:10
        _3 = const 7_u64;                // scope 1 at src\main.rs:7:18: 7:19
        StorageLive(_4);                 // scope 2 at src\main.rs:8:9: 8:10
        StorageLive(_5);                 // scope 2 at src\main.rs:8:18: 8:19
        _5 = _2;                         // scope 2 at src\main.rs:8:18: 8:19
        StorageLive(_6);                 // scope 2 at src\main.rs:8:22: 8:23
        _6 = _3;                         // scope 2 at src\main.rs:8:22: 8:23
        _7 = CheckedMul(_5, _6);         // scope 2 at src\main.rs:8:18: 8:23
        assert(!move (_7.1: bool), "attempt to compute `{} * {}`, which would overflow", move _5, move _6) -> bb1; // scope 2 at src\main.rs:8:18: 8:23
    }

    bb1: {
        _4 = move (_7.0: u64);           // scope 2 at src\main.rs:8:18: 8:23
        StorageDead(_6);                 // scope 2 at src\main.rs:8:22: 8:23
        StorageDead(_5);                 // scope 2 at src\main.rs:8:22: 8:23
        StorageLive(_8);                 // scope 3 at src\main.rs:10:5: 10:12
        goto -> bb2;                     // scope 3 at src\main.rs:10:5: 10:12
    }

    bb2: {
        _9 = const ();                   // scope 3 at src\main.rs:10:10: 10:12
        goto -> bb2;                     // scope 3 at src\main.rs:10:5: 10:12
    }
}

Can't find where preempt count in the stack is declared for a percpu variable access. (linux kernel)

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({
    typeof(printk_context) pscr_ret__;
    __verify_pcpu_ptr(&(printk_context));
    switch(sizeof(printk_context)) {
    case 1: pscr_ret__ = this_cpu_read_1(printk_context); break;
    case 2: pscr_ret__ = this_cpu_read_2(printk_context); break;
    case 4: pscr_ret__ = this_cpu_read_4(printk_context); break;
    case 8: pscr_ret__ = this_cpu_read_8(printk_context); break;
    default:
        __bad_size_call_parameter(); break;
    }
    pscr_ret__;
})

#define this_cpu_read_4(pcp)        \
    _pcp_protect_return(__percpu_read_32, pcp)

#define _pcp_protect_return(op, pcp, args...)               \
({                                  \
    typeof(pcp) __retval;                       \
    preempt_disable_notrace();                  \
    __retval = (typeof(pcp))op(raw_cpu_ptr(&(pcp)), ##args);    \
    preempt_enable_notrace();                   \
    __retval;                           \
})

#define preempt_enable_notrace() \
do { \
    barrier(); \
    __preempt_count_dec(); \
} while (0)

#define preempt_disable_notrace() \
do { \
    __preempt_count_inc(); \
    barrier(); \
} while (0)

#define __preempt_count_inc() __preempt_count_add(1)
#define __preempt_count_dec() __preempt_count_sub(1)

static inline void __preempt_count_add(int val)
{
    u32 pc = READ_ONCE(current_thread_info()->preempt.count);
    pc += val;
    WRITE_ONCE(current_thread_info()->preempt.count, pc);
}

static inline void __preempt_count_sub(int val)
{
    u32 pc = READ_ONCE(current_thread_info()->preempt.count);
    pc -= val;
    WRITE_ONCE(current_thread_info()->preempt.count, pc);
}

#ifdef CONFIG_THREAD_INFO_IN_TASK
/*
 * For CONFIG_THREAD_INFO_IN_TASK kernels we need <asm/current.h> for the
 * definition of current, but for !CONFIG_THREAD_INFO_IN_TASK kernels,
 * including <asm/current.h> can cause a circular dependency on some platforms.
 */
#include <asm/current.h>
#define current_thread_info() ((struct thread_info *)current)
#endif

#define current get_current()

/*
 * We don't use read_sysreg() as we want the compiler to cache the value where
 * possible.
 */
static __always_inline struct task_struct *get_current(void)
{
    unsigned long sp_el0;

    asm ("mrs %0, sp_el0" : "=r" (sp_el0));

    return (struct task_struct *)sp_el0;
}

struct task_struct {
#ifdef CONFIG_THREAD_INFO_IN_TASK
    /*
     * For reasons of header soup (see current_thread_info()), this
     * must be the first element of task_struct.
     */
    struct thread_info      thread_info;
#endif
    /* -1 unrunnable, 0 runnable, >0 stopped: */
    volatile long           state;

/*
 * low level task data that entry.S needs immediate access to.
 */
struct thread_info {
    unsigned long       flags;      /* low level flags */
    mm_segment_t        addr_limit; /* address limit */
#ifdef CONFIG_ARM64_SW_TTBR0_PAN
    u64         ttbr0;      /* saved TTBR0_EL1 */
#endif
    union {
        u64     preempt_count;  /* 0 => preemptible, <0 => bug */
        struct {
#ifdef CONFIG_CPU_BIG_ENDIAN
            u32 need_resched;
            u32 count;
#else
            u32 count;
            u32 need_resched;
#endif
        } preempt;
    };
};

({
    typeof(printk_context) pscr_ret__;
    __verify_pcpu_ptr(&(printk_context));
    switch(sizeof(printk_context)) {
    case 1: pscr_ret__ = this_cpu_read_1(printk_context); break;
    case 2: pscr_ret__ = this_cpu_read_2(printk_context); break;
    case 4: pscr_ret__ = this_cpu_read_4(printk_context); break;
    case 8: pscr_ret__ = this_cpu_read_8(printk_context); break;
    default:
        __bad_size_call_parameter(); break;
    }
    pscr_ret__;
})

#define this_cpu_read_4(pcp)        \
    _pcp_protect_return(__percpu_read_32, pcp)

#define _pcp_protect_return(op, pcp, args...)               \
({                                  \
    typeof(pcp) __retval;                       \
    preempt_disable_notrace();                  \
    __retval = (typeof(pcp))op(raw_cpu_ptr(&(pcp)), ##args);    \
    preempt_enable_notrace();                   \
    __retval;                           \
})

#define preempt_enable_notrace() \
do { \
    barrier(); \
    __preempt_count_dec(); \
} while (0)

#define preempt_disable_notrace() \
do { \
    __preempt_count_inc(); \
    barrier(); \
} while (0)

#define __preempt_count_inc() __preempt_count_add(1)
#define __preempt_count_dec() __preempt_count_sub(1)

static inline void __preempt_count_add(int val)
{
    u32 pc = READ_ONCE(current_thread_info()->preempt.count);
    pc += val;
    WRITE_ONCE(current_thread_info()->preempt.count, pc);
}

static inline void __preempt_count_sub(int val)
{
    u32 pc = READ_ONCE(current_thread_info()->preempt.count);
    pc -= val;
    WRITE_ONCE(current_thread_info()->preempt.count, pc);
}

#ifdef CONFIG_THREAD_INFO_IN_TASK
/*
 * For CONFIG_THREAD_INFO_IN_TASK kernels we need <asm/current.h> for the
 * definition of current, but for !CONFIG_THREAD_INFO_IN_TASK kernels,
 * including <asm/current.h> can cause a circular dependency on some platforms.
 */
#include <asm/current.h>
#define current_thread_info() ((struct thread_info *)current)
#endif

#define current get_current()

/*
 * We don't use read_sysreg() as we want the compiler to cache the value where
 * possible.
 */
static __always_inline struct task_struct *get_current(void)
{
    unsigned long sp_el0;

    asm ("mrs %0, sp_el0" : "=r" (sp_el0));

    return (struct task_struct *)sp_el0;
}

struct task_struct {
#ifdef CONFIG_THREAD_INFO_IN_TASK
    /*
     * For reasons of header soup (see current_thread_info()), this
     * must be the first element of task_struct.
     */
    struct thread_info      thread_info;
#endif
    /* -1 unrunnable, 0 runnable, >0 stopped: */
    volatile long           state;

/*
 * low level task data that entry.S needs immediate access to.
 */
struct thread_info {
    unsigned long       flags;      /* low level flags */
    mm_segment_t        addr_limit; /* address limit */
#ifdef CONFIG_ARM64_SW_TTBR0_PAN
    u64         ttbr0;      /* saved TTBR0_EL1 */
#endif
    union {
        u64     preempt_count;  /* 0 => preemptible, <0 => bug */
        struct {
#ifdef CONFIG_CPU_BIG_ENDIAN
            u32 need_resched;
            u32 count;
#else
            u32 count;
            u32 need_resched;
#endif
        } preempt;
    };
};

({
    typeof(printk_context) pscr_ret__;
    __verify_pcpu_ptr(&(printk_context));
    switch(sizeof(printk_context)) {
    case 1: pscr_ret__ = this_cpu_read_1(printk_context); break;
    case 2: pscr_ret__ = this_cpu_read_2(printk_context); break;
    case 4: pscr_ret__ = this_cpu_read_4(printk_context); break;
    case 8: pscr_ret__ = this_cpu_read_8(printk_context); break;
    default:
        __bad_size_call_parameter(); break;
    }
    pscr_ret__;
})

#define this_cpu_read_4(pcp)        \
    _pcp_protect_return(__percpu_read_32, pcp)

#define _pcp_protect_return(op, pcp, args...)               \
({                                  \
    typeof(pcp) __retval;                       \
    preempt_disable_notrace();                  \
    __retval = (typeof(pcp))op(raw_cpu_ptr(&(pcp)), ##args);    \
    preempt_enable_notrace();                   \
    __retval;                           \
})

#define preempt_enable_notrace() \
do { \
    barrier(); \
    __preempt_count_dec(); \
} while (0)

#define preempt_disable_notrace() \
do { \
    __preempt_count_inc(); \
    barrier(); \
} while (0)

#define __preempt_count_inc() __preempt_count_add(1)
#define __preempt_count_dec() __preempt_count_sub(1)

static inline void __preempt_count_add(int val)
{
    u32 pc = READ_ONCE(current_thread_info()->preempt.count);
    pc += val;
    WRITE_ONCE(current_thread_info()->preempt.count, pc);
}

static inline void __preempt_count_sub(int val)
{
    u32 pc = READ_ONCE(current_thread_info()->preempt.count);
    pc -= val;
    WRITE_ONCE(current_thread_info()->preempt.count, pc);
}

#ifdef CONFIG_THREAD_INFO_IN_TASK
/*
 * For CONFIG_THREAD_INFO_IN_TASK kernels we need <asm/current.h> for the
 * definition of current, but for !CONFIG_THREAD_INFO_IN_TASK kernels,
 * including <asm/current.h> can cause a circular dependency on some platforms.
 */
#include <asm/current.h>
#define current_thread_info() ((struct thread_info *)current)
#endif

#define current get_current()

/*
 * We don't use read_sysreg() as we want the compiler to cache the value where
 * possible.
 */
static __always_inline struct task_struct *get_current(void)
{
    unsigned long sp_el0;

    asm ("mrs %0, sp_el0" : "=r" (sp_el0));

    return (struct task_struct *)sp_el0;
}

struct task_struct {
#ifdef CONFIG_THREAD_INFO_IN_TASK
    /*
     * For reasons of header soup (see current_thread_info()), this
     * must be the first element of task_struct.
     */
    struct thread_info      thread_info;
#endif
    /* -1 unrunnable, 0 runnable, >0 stopped: */
    volatile long           state;

/*
 * low level task data that entry.S needs immediate access to.
 */
struct thread_info {
    unsigned long       flags;      /* low level flags */
    mm_segment_t        addr_limit; /* address limit */
#ifdef CONFIG_ARM64_SW_TTBR0_PAN
    u64         ttbr0;      /* saved TTBR0_EL1 */
#endif
    union {
        u64     preempt_count;  /* 0 => preemptible, <0 => bug */
        struct {
#ifdef CONFIG_CPU_BIG_ENDIAN
            u32 need_resched;
            u32 count;
#else
            u32 count;
            u32 need_resched;
#endif
        } preempt;
    };
};

({
    typeof(printk_context) pscr_ret__;
    __verify_pcpu_ptr(&(printk_context));
    switch(sizeof(printk_context)) {
    case 1: pscr_ret__ = this_cpu_read_1(printk_context); break;
    case 2: pscr_ret__ = this_cpu_read_2(printk_context); break;
    case 4: pscr_ret__ = this_cpu_read_4(printk_context); break;
    case 8: pscr_ret__ = this_cpu_read_8(printk_context); break;
    default:
        __bad_size_call_parameter(); break;
    }
    pscr_ret__;
})

#define this_cpu_read_4(pcp)        \
    _pcp_protect_return(__percpu_read_32, pcp)

#define _pcp_protect_return(op, pcp, args...)               \
({                                  \
    typeof(pcp) __retval;                       \
    preempt_disable_notrace();                  \
    __retval = (typeof(pcp))op(raw_cpu_ptr(&(pcp)), ##args);    \
    preempt_enable_notrace();                   \
    __retval;                           \
})

#define preempt_enable_notrace() \
do { \
    barrier(); \
    __preempt_count_dec(); \
} while (0)

#define preempt_disable_notrace() \
do { \
    __preempt_count_inc(); \
    barrier(); \
} while (0)

#define __preempt_count_inc() __preempt_count_add(1)
#define __preempt_count_dec() __preempt_count_sub(1)

static inline void __preempt_count_add(int val)
{
    u32 pc = READ_ONCE(current_thread_info()->preempt.count);
    pc += val;
    WRITE_ONCE(current_thread_info()->preempt.count, pc);
}

static inline void __preempt_count_sub(int val)
{
    u32 pc = READ_ONCE(current_thread_info()->preempt.count);
    pc -= val;
    WRITE_ONCE(current_thread_info()->preempt.count, pc);
}

#ifdef CONFIG_THREAD_INFO_IN_TASK
/*
 * For CONFIG_THREAD_INFO_IN_TASK kernels we need <asm/current.h> for the
 * definition of current, but for !CONFIG_THREAD_INFO_IN_TASK kernels,
 * including <asm/current.h> can cause a circular dependency on some platforms.
 */
#include <asm/current.h>
#define current_thread_info() ((struct thread_info *)current)
#endif

#define current get_current()

/*
 * We don't use read_sysreg() as we want the compiler to cache the value where
 * possible.
 */
static __always_inline struct task_struct *get_current(void)
{
    unsigned long sp_el0;

    asm ("mrs %0, sp_el0" : "=r" (sp_el0));

    return (struct task_struct *)sp_el0;
}

struct task_struct {
#ifdef CONFIG_THREAD_INFO_IN_TASK
    /*
     * For reasons of header soup (see current_thread_info()), this
     * must be the first element of task_struct.
     */
    struct thread_info      thread_info;
#endif
    /* -1 unrunnable, 0 runnable, >0 stopped: */
    volatile long           state;

/*
 * low level task data that entry.S needs immediate access to.
 */
struct thread_info {
    unsigned long       flags;      /* low level flags */
    mm_segment_t        addr_limit; /* address limit */
#ifdef CONFIG_ARM64_SW_TTBR0_PAN
    u64         ttbr0;      /* saved TTBR0_EL1 */
#endif
    union {
        u64     preempt_count;  /* 0 => preemptible, <0 => bug */
        struct {
#ifdef CONFIG_CPU_BIG_ENDIAN
            u32 need_resched;
            u32 count;
#else
            u32 count;
            u32 need_resched;
#endif
        } preempt;
    };
};

({
    typeof(printk_context) pscr_ret__;
    __verify_pcpu_ptr(&(printk_context));
    switch(sizeof(printk_context)) {
    case 1: pscr_ret__ = this_cpu_read_1(printk_context); break;
    case 2: pscr_ret__ = this_cpu_read_2(printk_context); break;
    case 4: pscr_ret__ = this_cpu_read_4(printk_context); break;
    case 8: pscr_ret__ = this_cpu_read_8(printk_context); break;
    default:
        __bad_size_call_parameter(); break;
    }
    pscr_ret__;
})

#define this_cpu_read_4(pcp)        \
    _pcp_protect_return(__percpu_read_32, pcp)

#define _pcp_protect_return(op, pcp, args...)               \
({                                  \
    typeof(pcp) __retval;                       \
    preempt_disable_notrace();                  \
    __retval = (typeof(pcp))op(raw_cpu_ptr(&(pcp)), ##args);    \
    preempt_enable_notrace();                   \
    __retval;                           \
})

#define preempt_enable_notrace() \
do { \
    barrier(); \
    __preempt_count_dec(); \
} while (0)

#define preempt_disable_notrace() \
do { \
    __preempt_count_inc(); \
    barrier(); \
} while (0)

#define __preempt_count_inc() __preempt_count_add(1)
#define __preempt_count_dec() __preempt_count_sub(1)

static inline void __preempt_count_add(int val)
{
    u32 pc = READ_ONCE(current_thread_info()->preempt.count);
    pc += val;
    WRITE_ONCE(current_thread_info()->preempt.count, pc);
}

static inline void __preempt_count_sub(int val)
{
    u32 pc = READ_ONCE(current_thread_info()->preempt.count);
    pc -= val;
    WRITE_ONCE(current_thread_info()->preempt.count, pc);
}

#ifdef CONFIG_THREAD_INFO_IN_TASK
/*
 * For CONFIG_THREAD_INFO_IN_TASK kernels we need <asm/current.h> for the
 * definition of current, but for !CONFIG_THREAD_INFO_IN_TASK kernels,
 * including <asm/current.h> can cause a circular dependency on some platforms.
 */
#include <asm/current.h>
#define current_thread_info() ((struct thread_info *)current)
#endif

#define current get_current()

/*
 * We don't use read_sysreg() as we want the compiler to cache the value where
 * possible.
 */
static __always_inline struct task_struct *get_current(void)
{
    unsigned long sp_el0;

    asm ("mrs %0, sp_el0" : "=r" (sp_el0));

    return (struct task_struct *)sp_el0;
}

struct task_struct {
#ifdef CONFIG_THREAD_INFO_IN_TASK
    /*
     * For reasons of header soup (see current_thread_info()), this
     * must be the first element of task_struct.
     */
    struct thread_info      thread_info;
#endif
    /* -1 unrunnable, 0 runnable, >0 stopped: */
    volatile long           state;

/*
 * low level task data that entry.S needs immediate access to.
 */
struct thread_info {
    unsigned long       flags;      /* low level flags */
    mm_segment_t        addr_limit; /* address limit */
#ifdef CONFIG_ARM64_SW_TTBR0_PAN
    u64         ttbr0;      /* saved TTBR0_EL1 */
#endif
    union {
        u64     preempt_count;  /* 0 => preemptible, <0 => bug */
        struct {
#ifdef CONFIG_CPU_BIG_ENDIAN
            u32 need_resched;
            u32 count;
#else
            u32 count;
            u32 need_resched;
#endif
        } preempt;
    };
};

({
    typeof(printk_context) pscr_ret__;
    __verify_pcpu_ptr(&(printk_context));
    switch(sizeof(printk_context)) {
    case 1: pscr_ret__ = this_cpu_read_1(printk_context); break;
    case 2: pscr_ret__ = this_cpu_read_2(printk_context); break;
    case 4: pscr_ret__ = this_cpu_read_4(printk_context); break;
    case 8: pscr_ret__ = this_cpu_read_8(printk_context); break;
    default:
        __bad_size_call_parameter(); break;
    }
    pscr_ret__;
})

#define this_cpu_read_4(pcp)        \
    _pcp_protect_return(__percpu_read_32, pcp)

#define _pcp_protect_return(op, pcp, args...)               \
({                                  \
    typeof(pcp) __retval;                       \
    preempt_disable_notrace();                  \
    __retval = (typeof(pcp))op(raw_cpu_ptr(&(pcp)), ##args);    \
    preempt_enable_notrace();                   \
    __retval;                           \
})

#define preempt_enable_notrace() \
do { \
    barrier(); \
    __preempt_count_dec(); \
} while (0)

#define preempt_disable_notrace() \
do { \
    __preempt_count_inc(); \
    barrier(); \
} while (0)

#define __preempt_count_inc() __preempt_count_add(1)
#define __preempt_count_dec() __preempt_count_sub(1)

static inline void __preempt_count_add(int val)
{
    u32 pc = READ_ONCE(current_thread_info()->preempt.count);
    pc += val;
    WRITE_ONCE(current_thread_info()->preempt.count, pc);
}

static inline void __preempt_count_sub(int val)
{
    u32 pc = READ_ONCE(current_thread_info()->preempt.count);
    pc -= val;
    WRITE_ONCE(current_thread_info()->preempt.count, pc);
}

#ifdef CONFIG_THREAD_INFO_IN_TASK
/*
 * For CONFIG_THREAD_INFO_IN_TASK kernels we need <asm/current.h> for the
 * definition of current, but for !CONFIG_THREAD_INFO_IN_TASK kernels,
 * including <asm/current.h> can cause a circular dependency on some platforms.
 */
#include <asm/current.h>
#define current_thread_info() ((struct thread_info *)current)
#endif

#define current get_current()

/*
 * We don't use read_sysreg() as we want the compiler to cache the value where
 * possible.
 */
static __always_inline struct task_struct *get_current(void)
{
    unsigned long sp_el0;

    asm ("mrs %0, sp_el0" : "=r" (sp_el0));

    return (struct task_struct *)sp_el0;
}

struct task_struct {
#ifdef CONFIG_THREAD_INFO_IN_TASK
    /*
     * For reasons of header soup (see current_thread_info()), this
     * must be the first element of task_struct.
     */
    struct thread_info      thread_info;
#endif
    /* -1 unrunnable, 0 runnable, >0 stopped: */
    volatile long           state;

/*
 * low level task data that entry.S needs immediate access to.
 */
struct thread_info {
    unsigned long       flags;      /* low level flags */
    mm_segment_t        addr_limit; /* address limit */
#ifdef CONFIG_ARM64_SW_TTBR0_PAN
    u64         ttbr0;      /* saved TTBR0_EL1 */
#endif
    union {
        u64     preempt_count;  /* 0 => preemptible, <0 => bug */
        struct {
#ifdef CONFIG_CPU_BIG_ENDIAN
            u32 need_resched;
            u32 count;
#else
            u32 count;
            u32 need_resched;
#endif
        } preempt;
    };
};

({
    typeof(printk_context) pscr_ret__;
    __verify_pcpu_ptr(&(printk_context));
    switch(sizeof(printk_context)) {
    case 1: pscr_ret__ = this_cpu_read_1(printk_context); break;
    case 2: pscr_ret__ = this_cpu_read_2(printk_context); break;
    case 4: pscr_ret__ = this_cpu_read_4(printk_context); break;
    case 8: pscr_ret__ = this_cpu_read_8(printk_context); break;
    default:
        __bad_size_call_parameter(); break;
    }
    pscr_ret__;
})

#define this_cpu_read_4(pcp)        \
    _pcp_protect_return(__percpu_read_32, pcp)

#define _pcp_protect_return(op, pcp, args...)               \
({                                  \
    typeof(pcp) __retval;                       \
    preempt_disable_notrace();                  \
    __retval = (typeof(pcp))op(raw_cpu_ptr(&(pcp)), ##args);    \
    preempt_enable_notrace();                   \
    __retval;                           \
})

#define preempt_enable_notrace() \
do { \
    barrier(); \
    __preempt_count_dec(); \
} while (0)

#define preempt_disable_notrace() \
do { \
    __preempt_count_inc(); \
    barrier(); \
} while (0)

#define __preempt_count_inc() __preempt_count_add(1)
#define __preempt_count_dec() __preempt_count_sub(1)

static inline void __preempt_count_add(int val)
{
    u32 pc = READ_ONCE(current_thread_info()->preempt.count);
    pc += val;
    WRITE_ONCE(current_thread_info()->preempt.count, pc);
}

static inline void __preempt_count_sub(int val)
{
    u32 pc = READ_ONCE(current_thread_info()->preempt.count);
    pc -= val;
    WRITE_ONCE(current_thread_info()->preempt.count, pc);
}

#ifdef CONFIG_THREAD_INFO_IN_TASK
/*
 * For CONFIG_THREAD_INFO_IN_TASK kernels we need <asm/current.h> for the
 * definition of current, but for !CONFIG_THREAD_INFO_IN_TASK kernels,
 * including <asm/current.h> can cause a circular dependency on some platforms.
 */
#include <asm/current.h>
#define current_thread_info() ((struct thread_info *)current)
#endif

#define current get_current()

/*
 * We don't use read_sysreg() as we want the compiler to cache the value where
 * possible.
 */
static __always_inline struct task_struct *get_current(void)
{
    unsigned long sp_el0;

    asm ("mrs %0, sp_el0" : "=r" (sp_el0));

    return (struct task_struct *)sp_el0;
}

struct task_struct {
#ifdef CONFIG_THREAD_INFO_IN_TASK
    /*
     * For reasons of header soup (see current_thread_info()), this
     * must be the first element of task_struct.
     */
    struct thread_info      thread_info;
#endif
    /* -1 unrunnable, 0 runnable, >0 stopped: */
    volatile long           state;

/*
 * low level task data that entry.S needs immediate access to.
 */
struct thread_info {
    unsigned long       flags;      /* low level flags */
    mm_segment_t        addr_limit; /* address limit */
#ifdef CONFIG_ARM64_SW_TTBR0_PAN
    u64         ttbr0;      /* saved TTBR0_EL1 */
#endif
    union {
        u64     preempt_count;  /* 0 => preemptible, <0 => bug */
        struct {
#ifdef CONFIG_CPU_BIG_ENDIAN
            u32 need_resched;
            u32 count;
#else
            u32 count;
            u32 need_resched;
#endif
        } preempt;
    };
};

({
    typeof(printk_context) pscr_ret__;
    __verify_pcpu_ptr(&(printk_context));
    switch(sizeof(printk_context)) {
    case 1: pscr_ret__ = this_cpu_read_1(printk_context); break;
    case 2: pscr_ret__ = this_cpu_read_2(printk_context); break;
    case 4: pscr_ret__ = this_cpu_read_4(printk_context); break;
    case 8: pscr_ret__ = this_cpu_read_8(printk_context); break;
    default:
        __bad_size_call_parameter(); break;
    }
    pscr_ret__;
})

#define this_cpu_read_4(pcp)        \
    _pcp_protect_return(__percpu_read_32, pcp)

#define _pcp_protect_return(op, pcp, args...)               \
({                                  \
    typeof(pcp) __retval;                       \
    preempt_disable_notrace();                  \
    __retval = (typeof(pcp))op(raw_cpu_ptr(&(pcp)), ##args);    \
    preempt_enable_notrace();                   \
    __retval;                           \
})

#define preempt_enable_notrace() \
do { \
    barrier(); \
    __preempt_count_dec(); \
} while (0)

#define preempt_disable_notrace() \
do { \
    __preempt_count_inc(); \
    barrier(); \
} while (0)

#define __preempt_count_inc() __preempt_count_add(1)
#define __preempt_count_dec() __preempt_count_sub(1)

static inline void __preempt_count_add(int val)
{
    u32 pc = READ_ONCE(current_thread_info()->preempt.count);
    pc += val;
    WRITE_ONCE(current_thread_info()->preempt.count, pc);
}

static inline void __preempt_count_sub(int val)
{
    u32 pc = READ_ONCE(current_thread_info()->preempt.count);
    pc -= val;
    WRITE_ONCE(current_thread_info()->preempt.count, pc);
}

#ifdef CONFIG_THREAD_INFO_IN_TASK
/*
 * For CONFIG_THREAD_INFO_IN_TASK kernels we need <asm/current.h> for the
 * definition of current, but for !CONFIG_THREAD_INFO_IN_TASK kernels,
 * including <asm/current.h> can cause a circular dependency on some platforms.
 */
#include <asm/current.h>
#define current_thread_info() ((struct thread_info *)current)
#endif

#define current get_current()

/*
 * We don't use read_sysreg() as we want the compiler to cache the value where
 * possible.
 */
static __always_inline struct task_struct *get_current(void)
{
    unsigned long sp_el0;

    asm ("mrs %0, sp_el0" : "=r" (sp_el0));

    return (struct task_struct *)sp_el0;
}

struct task_struct {
#ifdef CONFIG_THREAD_INFO_IN_TASK
    /*
     * For reasons of header soup (see current_thread_info()), this
     * must be the first element of task_struct.
     */
    struct thread_info      thread_info;
#endif
    /* -1 unrunnable, 0 runnable, >0 stopped: */
    volatile long           state;

/*
 * low level task data that entry.S needs immediate access to.
 */
struct thread_info {
    unsigned long       flags;      /* low level flags */
    mm_segment_t        addr_limit; /* address limit */
#ifdef CONFIG_ARM64_SW_TTBR0_PAN
    u64         ttbr0;      /* saved TTBR0_EL1 */
#endif
    union {
        u64     preempt_count;  /* 0 => preemptible, <0 => bug */
        struct {
#ifdef CONFIG_CPU_BIG_ENDIAN
            u32 need_resched;
            u32 count;
#else
            u32 count;
            u32 need_resched;
#endif
        } preempt;
    };
};

({
    typeof(printk_context) pscr_ret__;
    __verify_pcpu_ptr(&(printk_context));
    switch(sizeof(printk_context)) {
    case 1: pscr_ret__ = this_cpu_read_1(printk_context); break;
    case 2: pscr_ret__ = this_cpu_read_2(printk_context); break;
    case 4: pscr_ret__ = this_cpu_read_4(printk_context); break;
    case 8: pscr_ret__ = this_cpu_read_8(printk_context); break;
    default:
        __bad_size_call_parameter(); break;
    }
    pscr_ret__;
})

#define this_cpu_read_4(pcp)        \
    _pcp_protect_return(__percpu_read_32, pcp)

#define _pcp_protect_return(op, pcp, args...)               \
({                                  \
    typeof(pcp) __retval;                       \
    preempt_disable_notrace();                  \
    __retval = (typeof(pcp))op(raw_cpu_ptr(&(pcp)), ##args);    \
    preempt_enable_notrace();                   \
    __retval;                           \
})

#define preempt_enable_notrace() \
do { \
    barrier(); \
    __preempt_count_dec(); \
} while (0)

#define preempt_disable_notrace() \
do { \
    __preempt_count_inc(); \
    barrier(); \
} while (0)

#define __preempt_count_inc() __preempt_count_add(1)
#define __preempt_count_dec() __preempt_count_sub(1)

static inline void __preempt_count_add(int val)
{
    u32 pc = READ_ONCE(current_thread_info()->preempt.count);
    pc += val;
    WRITE_ONCE(current_thread_info()->preempt.count, pc);
}

static inline void __preempt_count_sub(int val)
{
    u32 pc = READ_ONCE(current_thread_info()->preempt.count);
    pc -= val;
    WRITE_ONCE(current_thread_info()->preempt.count, pc);
}

#ifdef CONFIG_THREAD_INFO_IN_TASK
/*
 * For CONFIG_THREAD_INFO_IN_TASK kernels we need <asm/current.h> for the
 * definition of current, but for !CONFIG_THREAD_INFO_IN_TASK kernels,
 * including <asm/current.h> can cause a circular dependency on some platforms.
 */
#include <asm/current.h>
#define current_thread_info() ((struct thread_info *)current)
#endif

#define current get_current()

/*
 * We don't use read_sysreg() as we want the compiler to cache the value where
 * possible.
 */
static __always_inline struct task_struct *get_current(void)
{
    unsigned long sp_el0;

    asm ("mrs %0, sp_el0" : "=r" (sp_el0));

    return (struct task_struct *)sp_el0;
}

struct task_struct {
#ifdef CONFIG_THREAD_INFO_IN_TASK
    /*
     * For reasons of header soup (see current_thread_info()), this
     * must be the first element of task_struct.
     */
    struct thread_info      thread_info;
#endif
    /* -1 unrunnable, 0 runnable, >0 stopped: */
    volatile long           state;

/*
 * low level task data that entry.S needs immediate access to.
 */
struct thread_info {
    unsigned long       flags;      /* low level flags */
    mm_segment_t        addr_limit; /* address limit */
#ifdef CONFIG_ARM64_SW_TTBR0_PAN
    u64         ttbr0;      /* saved TTBR0_EL1 */
#endif
    union {
        u64     preempt_count;  /* 0 => preemptible, <0 => bug */
        struct {
#ifdef CONFIG_CPU_BIG_ENDIAN
            u32 need_resched;
            u32 count;
#else
            u32 count;
            u32 need_resched;
#endif
        } preempt;
    };
};

({
    typeof(printk_context) pscr_ret__;
    __verify_pcpu_ptr(&(printk_context));
    switch(sizeof(printk_context)) {
    case 1: pscr_ret__ = this_cpu_read_1(printk_context); break;
    case 2: pscr_ret__ = this_cpu_read_2(printk_context); break;
    case 4: pscr_ret__ = this_cpu_read_4(printk_context); break;
    case 8: pscr_ret__ = this_cpu_read_8(printk_context); break;
    default:
        __bad_size_call_parameter(); break;
    }
    pscr_ret__;
})

#define this_cpu_read_4(pcp)        \
    _pcp_protect_return(__percpu_read_32, pcp)

#define _pcp_protect_return(op, pcp, args...)               \
({                                  \
    typeof(pcp) __retval;                       \
    preempt_disable_notrace();                  \
    __retval = (typeof(pcp))op(raw_cpu_ptr(&(pcp)), ##args);    \
    preempt_enable_notrace();                   \
    __retval;                           \
})

#define preempt_enable_notrace() \
do { \
    barrier(); \
    __preempt_count_dec(); \
} while (0)

#define preempt_disable_notrace() \
do { \
    __preempt_count_inc(); \
    barrier(); \
} while (0)

#define __preempt_count_inc() __preempt_count_add(1)
#define __preempt_count_dec() __preempt_count_sub(1)

static inline void __preempt_count_add(int val)
{
    u32 pc = READ_ONCE(current_thread_info()->preempt.count);
    pc += val;
    WRITE_ONCE(current_thread_info()->preempt.count, pc);
}

static inline void __preempt_count_sub(int val)
{
    u32 pc = READ_ONCE(current_thread_info()->preempt.count);
    pc -= val;
    WRITE_ONCE(current_thread_info()->preempt.count, pc);
}

#ifdef CONFIG_THREAD_INFO_IN_TASK
/*
 * For CONFIG_THREAD_INFO_IN_TASK kernels we need <asm/current.h> for the
 * definition of current, but for !CONFIG_THREAD_INFO_IN_TASK kernels,
 * including <asm/current.h> can cause a circular dependency on some platforms.
 */
#include <asm/current.h>
#define current_thread_info() ((struct thread_info *)current)
#endif

#define current get_current()

/*
 * We don't use read_sysreg() as we want the compiler to cache the value where
 * possible.
 */
static __always_inline struct task_struct *get_current(void)
{
    unsigned long sp_el0;

    asm ("mrs %0, sp_el0" : "=r" (sp_el0));

    return (struct task_struct *)sp_el0;
}

struct task_struct {
#ifdef CONFIG_THREAD_INFO_IN_TASK
    /*
     * For reasons of header soup (see current_thread_info()), this
     * must be the first element of task_struct.
     */
    struct thread_info      thread_info;
#endif
    /* -1 unrunnable, 0 runnable, >0 stopped: */
    volatile long           state;

/*
 * low level task data that entry.S needs immediate access to.
 */
struct thread_info {
    unsigned long       flags;      /* low level flags */
    mm_segment_t        addr_limit; /* address limit */
#ifdef CONFIG_ARM64_SW_TTBR0_PAN
    u64         ttbr0;      /* saved TTBR0_EL1 */
#endif
    union {
        u64     preempt_count;  /* 0 => preemptible, <0 => bug */
        struct {
#ifdef CONFIG_CPU_BIG_ENDIAN
            u32 need_resched;
            u32 count;
#else
            u32 count;
            u32 need_resched;
#endif
        } preempt;
    };
};

({
    typeof(printk_context) pscr_ret__;
    __verify_pcpu_ptr(&(printk_context));
    switch(sizeof(printk_context)) {
    case 1: pscr_ret__ = this_cpu_read_1(printk_context); break;
    case 2: pscr_ret__ = this_cpu_read_2(printk_context); break;
    case 4: pscr_ret__ = this_cpu_read_4(printk_context); break;
    case 8: pscr_ret__ = this_cpu_read_8(printk_context); break;
    default:
        __bad_size_call_parameter(); break;
    }
    pscr_ret__;
})

#define this_cpu_read_4(pcp)        \
    _pcp_protect_return(__percpu_read_32, pcp)

#define _pcp_protect_return(op, pcp, args...)               \
({                                  \
    typeof(pcp) __retval;                       \
    preempt_disable_notrace();                  \
    __retval = (typeof(pcp))op(raw_cpu_ptr(&(pcp)), ##args);    \
    preempt_enable_notrace();                   \
    __retval;                           \
})

#define preempt_enable_notrace() \
do { \
    barrier(); \
    __preempt_count_dec(); \
} while (0)

#define preempt_disable_notrace() \
do { \
    __preempt_count_inc(); \
    barrier(); \
} while (0)

#define __preempt_count_inc() __preempt_count_add(1)
#define __preempt_count_dec() __preempt_count_sub(1)

static inline void __preempt_count_add(int val)
{
    u32 pc = READ_ONCE(current_thread_info()->preempt.count);
    pc += val;
    WRITE_ONCE(current_thread_info()->preempt.count, pc);
}

static inline void __preempt_count_sub(int val)
{
    u32 pc = READ_ONCE(current_thread_info()->preempt.count);
    pc -= val;
    WRITE_ONCE(current_thread_info()->preempt.count, pc);
}

#ifdef CONFIG_THREAD_INFO_IN_TASK
/*
 * For CONFIG_THREAD_INFO_IN_TASK kernels we need <asm/current.h> for the
 * definition of current, but for !CONFIG_THREAD_INFO_IN_TASK kernels,
 * including <asm/current.h> can cause a circular dependency on some platforms.
 */
#include <asm/current.h>
#define current_thread_info() ((struct thread_info *)current)
#endif

#define current get_current()

/*
 * We don't use read_sysreg() as we want the compiler to cache the value where
 * possible.
 */
static __always_inline struct task_struct *get_current(void)
{
    unsigned long sp_el0;

    asm ("mrs %0, sp_el0" : "=r" (sp_el0));

    return (struct task_struct *)sp_el0;
}

struct task_struct {
#ifdef CONFIG_THREAD_INFO_IN_TASK
    /*
     * For reasons of header soup (see current_thread_info()), this
     * must be the first element of task_struct.
     */
    struct thread_info      thread_info;
#endif
    /* -1 unrunnable, 0 runnable, >0 stopped: */
    volatile long           state;

/*
 * low level task data that entry.S needs immediate access to.
 */
struct thread_info {
    unsigned long       flags;      /* low level flags */
    mm_segment_t        addr_limit; /* address limit */
#ifdef CONFIG_ARM64_SW_TTBR0_PAN
    u64         ttbr0;      /* saved TTBR0_EL1 */
#endif
    union {
        u64     preempt_count;  /* 0 => preemptible, <0 => bug */
        struct {
#ifdef CONFIG_CPU_BIG_ENDIAN
            u32 need_resched;
            u32 count;
#else
            u32 count;
            u32 need_resched;
#endif
        } preempt;
    };
};

({
    typeof(printk_context) pscr_ret__;
    __verify_pcpu_ptr(&(printk_context));
    switch(sizeof(printk_context)) {
    case 1: pscr_ret__ = this_cpu_read_1(printk_context); break;
    case 2: pscr_ret__ = this_cpu_read_2(printk_context); break;
    case 4: pscr_ret__ = this_cpu_read_4(printk_context); break;
    case 8: pscr_ret__ = this_cpu_read_8(printk_context); break;
    default:
        __bad_size_call_parameter(); break;
    }
    pscr_ret__;
})

#define this_cpu_read_4(pcp)        \
    _pcp_protect_return(__percpu_read_32, pcp)

#define _pcp_protect_return(op, pcp, args...)               \
({                                  \
    typeof(pcp) __retval;                       \
    preempt_disable_notrace();                  \
    __retval = (typeof(pcp))op(raw_cpu_ptr(&(pcp)), ##args);    \
    preempt_enable_notrace();                   \
    __retval;                           \
})

#define preempt_enable_notrace() \
do { \
    barrier(); \
    __preempt_count_dec(); \
} while (0)

#define preempt_disable_notrace() \
do { \
    __preempt_count_inc(); \
    barrier(); \
} while (0)

#define __preempt_count_inc() __preempt_count_add(1)
#define __preempt_count_dec() __preempt_count_sub(1)

static inline void __preempt_count_add(int val)
{
    u32 pc = READ_ONCE(current_thread_info()->preempt.count);
    pc += val;
    WRITE_ONCE(current_thread_info()->preempt.count, pc);
}

static inline void __preempt_count_sub(int val)
{
    u32 pc = READ_ONCE(current_thread_info()->preempt.count);
    pc -= val;
    WRITE_ONCE(current_thread_info()->preempt.count, pc);
}

#ifdef CONFIG_THREAD_INFO_IN_TASK
/*
 * For CONFIG_THREAD_INFO_IN_TASK kernels we need <asm/current.h> for the
 * definition of current, but for !CONFIG_THREAD_INFO_IN_TASK kernels,
 * including <asm/current.h> can cause a circular dependency on some platforms.
 */
#include <asm/current.h>
#define current_thread_info() ((struct thread_info *)current)
#endif

#define current get_current()

/*
 * We don't use read_sysreg() as we want the compiler to cache the value where
 * possible.
 */
static __always_inline struct task_struct *get_current(void)
{
    unsigned long sp_el0;

    asm ("mrs %0, sp_el0" : "=r" (sp_el0));

    return (struct task_struct *)sp_el0;
}

struct task_struct {
#ifdef CONFIG_THREAD_INFO_IN_TASK
    /*
     * For reasons of header soup (see current_thread_info()), this
     * must be the first element of task_struct.
     */
    struct thread_info      thread_info;
#endif
    /* -1 unrunnable, 0 runnable, >0 stopped: */
    volatile long           state;

/*
 * low level task data that entry.S needs immediate access to.
 */
struct thread_info {
    unsigned long       flags;      /* low level flags */
    mm_segment_t        addr_limit; /* address limit */
#ifdef CONFIG_ARM64_SW_TTBR0_PAN
    u64         ttbr0;      /* saved TTBR0_EL1 */
#endif
    union {
        u64     preempt_count;  /* 0 => preemptible, <0 => bug */
        struct {
#ifdef CONFIG_CPU_BIG_ENDIAN
            u32 need_resched;
            u32 count;
#else
            u32 count;
            u32 need_resched;
#endif
        } preempt;
    };
};

GDB stepping through instructions on a particular core in baremetal development on QEMU

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        .global _start
_start:
1:      wfe
        b 1b

/opt/arm/10/gcc-arm-10.3-2021.07-x86_64-aarch64-none-elf/bin/aarch64-none-elf-gcc -g -ffreestanding -nostdlib -nostartfiles -Wl,-Ttext=0x80000 -o wfe.elf wfe.s

/opt/arm/10/gcc-arm-10.3-2021.07-x86_64-aarch64-none-elf/bin/aarch64-none-elf-objdump -d wfe.elf

wfe.elf:     file format elf64-littleaarch64


Disassembly of section .text:

0000000000080000 <_stack>:
   80000:       d503205f        wfe
   80004:       17ffffff        b       80000 <_stack>

/opt/qemu-6.2.0/bin/qemu-system-aarch64 -M raspi3b -kernel wfe.elf -display none -S -s

/opt/gdb/gdb-10.1-aarch64-elf-x86_64-linux-gnu/bin/aarch64-elf-gdb wfe.elf -ex 'target remote localhost:1234' -ex 'break *0x80000' -ex 'continue'

GNU gdb (GDB) 10.1
Copyright (C) 2020 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
Type "show copying" and "show warranty" for details.
This GDB was configured as "--host=x86_64-linux-gnu --target=aarch64-elf".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<https://www.gnu.org/software/gdb/bugs/>.
Find the GDB manual and other documentation resources online at:
    <http://www.gnu.org/software/gdb/documentation/>.

For help, type "help".
Type "apropos word" to search for commands related to "word".
Remote debugging using localhost:1234
warning: No executable has been specified and target does not support
determining executable automatically.  Try using the "file" command.
0x0000000000080000 in ?? ()
Breakpoint 1 at 0x80000
Continuing.
[Switching to Thread 1.4]

Thread 4 hit Breakpoint 1, 0x0000000000080000 in ?? ()
(gdb) break *0x80000 thread 2
Note: breakpoint 1 (all threads) also set at pc 0x80000.
Breakpoint 2 at 0x80000
(gdb) info threads
  Id   Target Id                    Frame 
  1    Thread 1.1 (CPU#0 [running]) 0x0000000000080000 in ?? ()
  2    Thread 1.2 (CPU#1 [running]) 0x0000000000080000 in ?? ()
  3    Thread 1.3 (CPU#2 [running]) 0x0000000000080000 in ?? ()
* 4    Thread 1.4 (CPU#3 [running]) 0x0000000000080000 in ?? ()
(gdb) c
Continuing.
[Switching to Thread 1.2]

Thread 2 hit Breakpoint 1, 0x0000000000080000 in ?? ()
(gdb) info b
Num     Type           Disp Enb Address            What
1       breakpoint     keep y   0x0000000000080000 
        breakpoint already hit 2 times
2       breakpoint     keep y   0x0000000000080000  thread 2
        stop only in thread 2
        breakpoint already hit 1 time
(gdb) del 1
(gdb) info b
Num     Type           Disp Enb Address            What
2       breakpoint     keep y   0x0000000000080000  thread 2
        stop only in thread 2
        breakpoint already hit 1 time
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, 0x0000000000080000 in ?? ()
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, 0x0000000000080000 in ?? ()
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, 0x0000000000080000 in ?? ()
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, 0x0000000000080000 in ?? ()
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, 0x0000000000080000 in ?? ()
(gdb)

/opt/arm/10/gcc-arm-10.3-2021.07-x86_64-aarch64-none-elf/bin/aarch64-none-elf-gdb wfe.elf -ex 'target remote localhost:1234' -ex 'break *0x80000' -ex 'continue'
GNU gdb (GNU Toolchain for the A-profile Architecture 10.3-2021.07 (arm-10.29)) 10.2.90.20210621-git
Copyright (C) 2021 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
Type "show copying" and "show warranty" for details.
This GDB was configured as "--host=x86_64-pc-linux-gnu --target=aarch64-none-elf".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<https://bugs.linaro.org/>.
Find the GDB manual and other documentation resources online at:
    <http://www.gnu.org/software/gdb/documentation/>.

For help, type "help".
Type "apropos word" to search for commands related to "word"...
Reading symbols from wfe.elf...
Remote debugging using localhost:1234
_start () at wfe.s:3
3       1:      wfe
Breakpoint 1 at 0x80000: file wfe.s, line 3.
Continuing.

Thread 1 hit Breakpoint 1, _start () at wfe.s:3
3       1:      wfe
(gdb) break *0x80000 thread 2
Note: breakpoint 1 (all threads) also set at pc 0x80000.
Breakpoint 2 at 0x80000: file wfe.s, line 3.
(gdb)  info threads
  Id   Target Id                    Frame 
* 1    Thread 1.1 (CPU#0 [running]) _start () at wfe.s:3
  2    Thread 1.2 (CPU#1 [running]) _start () at wfe.s:3
  3    Thread 1.3 (CPU#2 [running]) _start () at wfe.s:3
  4    Thread 1.4 (CPU#3 [running]) _start () at wfe.s:3
(gdb) c
Continuing.
[Switching to Thread 1.2]

Thread 2 hit Breakpoint 1, _start () at wfe.s:3
3       1:      wfe
(gdb) info b
Num     Type           Disp Enb Address            What
1       breakpoint     keep y   0x0000000000080000 wfe.s:3
        breakpoint already hit 2 times
2       breakpoint     keep y   0x0000000000080000 wfe.s:3 thread 2
        stop only in thread 2
        breakpoint already hit 1 time
(gdb) del 1
(gdb) info b
Num     Type           Disp Enb Address            What
2       breakpoint     keep y   0x0000000000080000 wfe.s:3 thread 2
        stop only in thread 2
        breakpoint already hit 1 time
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, _start () at wfe.s:3
3       1:      wfe
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, _start () at wfe.s:3
3       1:      wfe
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, _start () at wfe.s:3
3       1:      wfe
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, _start () at wfe.s:3
3       1:      wfe
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, _start () at wfe.s:3
3       1:      wfe
(gdb)

        .global _start
_start:
1:      wfe
        b 1b

/opt/arm/10/gcc-arm-10.3-2021.07-x86_64-aarch64-none-elf/bin/aarch64-none-elf-gcc -g -ffreestanding -nostdlib -nostartfiles -Wl,-Ttext=0x80000 -o wfe.elf wfe.s

/opt/arm/10/gcc-arm-10.3-2021.07-x86_64-aarch64-none-elf/bin/aarch64-none-elf-objdump -d wfe.elf

wfe.elf:     file format elf64-littleaarch64


Disassembly of section .text:

0000000000080000 <_stack>:
   80000:       d503205f        wfe
   80004:       17ffffff        b       80000 <_stack>

/opt/qemu-6.2.0/bin/qemu-system-aarch64 -M raspi3b -kernel wfe.elf -display none -S -s

/opt/gdb/gdb-10.1-aarch64-elf-x86_64-linux-gnu/bin/aarch64-elf-gdb wfe.elf -ex 'target remote localhost:1234' -ex 'break *0x80000' -ex 'continue'

GNU gdb (GDB) 10.1
Copyright (C) 2020 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
Type "show copying" and "show warranty" for details.
This GDB was configured as "--host=x86_64-linux-gnu --target=aarch64-elf".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<https://www.gnu.org/software/gdb/bugs/>.
Find the GDB manual and other documentation resources online at:
    <http://www.gnu.org/software/gdb/documentation/>.

For help, type "help".
Type "apropos word" to search for commands related to "word".
Remote debugging using localhost:1234
warning: No executable has been specified and target does not support
determining executable automatically.  Try using the "file" command.
0x0000000000080000 in ?? ()
Breakpoint 1 at 0x80000
Continuing.
[Switching to Thread 1.4]

Thread 4 hit Breakpoint 1, 0x0000000000080000 in ?? ()
(gdb) break *0x80000 thread 2
Note: breakpoint 1 (all threads) also set at pc 0x80000.
Breakpoint 2 at 0x80000
(gdb) info threads
  Id   Target Id                    Frame 
  1    Thread 1.1 (CPU#0 [running]) 0x0000000000080000 in ?? ()
  2    Thread 1.2 (CPU#1 [running]) 0x0000000000080000 in ?? ()
  3    Thread 1.3 (CPU#2 [running]) 0x0000000000080000 in ?? ()
* 4    Thread 1.4 (CPU#3 [running]) 0x0000000000080000 in ?? ()
(gdb) c
Continuing.
[Switching to Thread 1.2]

Thread 2 hit Breakpoint 1, 0x0000000000080000 in ?? ()
(gdb) info b
Num     Type           Disp Enb Address            What
1       breakpoint     keep y   0x0000000000080000 
        breakpoint already hit 2 times
2       breakpoint     keep y   0x0000000000080000  thread 2
        stop only in thread 2
        breakpoint already hit 1 time
(gdb) del 1
(gdb) info b
Num     Type           Disp Enb Address            What
2       breakpoint     keep y   0x0000000000080000  thread 2
        stop only in thread 2
        breakpoint already hit 1 time
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, 0x0000000000080000 in ?? ()
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, 0x0000000000080000 in ?? ()
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, 0x0000000000080000 in ?? ()
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, 0x0000000000080000 in ?? ()
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, 0x0000000000080000 in ?? ()
(gdb)

/opt/arm/10/gcc-arm-10.3-2021.07-x86_64-aarch64-none-elf/bin/aarch64-none-elf-gdb wfe.elf -ex 'target remote localhost:1234' -ex 'break *0x80000' -ex 'continue'
GNU gdb (GNU Toolchain for the A-profile Architecture 10.3-2021.07 (arm-10.29)) 10.2.90.20210621-git
Copyright (C) 2021 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
Type "show copying" and "show warranty" for details.
This GDB was configured as "--host=x86_64-pc-linux-gnu --target=aarch64-none-elf".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<https://bugs.linaro.org/>.
Find the GDB manual and other documentation resources online at:
    <http://www.gnu.org/software/gdb/documentation/>.

For help, type "help".
Type "apropos word" to search for commands related to "word"...
Reading symbols from wfe.elf...
Remote debugging using localhost:1234
_start () at wfe.s:3
3       1:      wfe
Breakpoint 1 at 0x80000: file wfe.s, line 3.
Continuing.

Thread 1 hit Breakpoint 1, _start () at wfe.s:3
3       1:      wfe
(gdb) break *0x80000 thread 2
Note: breakpoint 1 (all threads) also set at pc 0x80000.
Breakpoint 2 at 0x80000: file wfe.s, line 3.
(gdb)  info threads
  Id   Target Id                    Frame 
* 1    Thread 1.1 (CPU#0 [running]) _start () at wfe.s:3
  2    Thread 1.2 (CPU#1 [running]) _start () at wfe.s:3
  3    Thread 1.3 (CPU#2 [running]) _start () at wfe.s:3
  4    Thread 1.4 (CPU#3 [running]) _start () at wfe.s:3
(gdb) c
Continuing.
[Switching to Thread 1.2]

Thread 2 hit Breakpoint 1, _start () at wfe.s:3
3       1:      wfe
(gdb) info b
Num     Type           Disp Enb Address            What
1       breakpoint     keep y   0x0000000000080000 wfe.s:3
        breakpoint already hit 2 times
2       breakpoint     keep y   0x0000000000080000 wfe.s:3 thread 2
        stop only in thread 2
        breakpoint already hit 1 time
(gdb) del 1
(gdb) info b
Num     Type           Disp Enb Address            What
2       breakpoint     keep y   0x0000000000080000 wfe.s:3 thread 2
        stop only in thread 2
        breakpoint already hit 1 time
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, _start () at wfe.s:3
3       1:      wfe
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, _start () at wfe.s:3
3       1:      wfe
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, _start () at wfe.s:3
3       1:      wfe
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, _start () at wfe.s:3
3       1:      wfe
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, _start () at wfe.s:3
3       1:      wfe
(gdb)

        .global _start
_start:
1:      wfe
        b 1b

/opt/arm/10/gcc-arm-10.3-2021.07-x86_64-aarch64-none-elf/bin/aarch64-none-elf-gcc -g -ffreestanding -nostdlib -nostartfiles -Wl,-Ttext=0x80000 -o wfe.elf wfe.s

/opt/arm/10/gcc-arm-10.3-2021.07-x86_64-aarch64-none-elf/bin/aarch64-none-elf-objdump -d wfe.elf

wfe.elf:     file format elf64-littleaarch64


Disassembly of section .text:

0000000000080000 <_stack>:
   80000:       d503205f        wfe
   80004:       17ffffff        b       80000 <_stack>

/opt/qemu-6.2.0/bin/qemu-system-aarch64 -M raspi3b -kernel wfe.elf -display none -S -s

/opt/gdb/gdb-10.1-aarch64-elf-x86_64-linux-gnu/bin/aarch64-elf-gdb wfe.elf -ex 'target remote localhost:1234' -ex 'break *0x80000' -ex 'continue'

GNU gdb (GDB) 10.1
Copyright (C) 2020 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
Type "show copying" and "show warranty" for details.
This GDB was configured as "--host=x86_64-linux-gnu --target=aarch64-elf".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<https://www.gnu.org/software/gdb/bugs/>.
Find the GDB manual and other documentation resources online at:
    <http://www.gnu.org/software/gdb/documentation/>.

For help, type "help".
Type "apropos word" to search for commands related to "word".
Remote debugging using localhost:1234
warning: No executable has been specified and target does not support
determining executable automatically.  Try using the "file" command.
0x0000000000080000 in ?? ()
Breakpoint 1 at 0x80000
Continuing.
[Switching to Thread 1.4]

Thread 4 hit Breakpoint 1, 0x0000000000080000 in ?? ()
(gdb) break *0x80000 thread 2
Note: breakpoint 1 (all threads) also set at pc 0x80000.
Breakpoint 2 at 0x80000
(gdb) info threads
  Id   Target Id                    Frame 
  1    Thread 1.1 (CPU#0 [running]) 0x0000000000080000 in ?? ()
  2    Thread 1.2 (CPU#1 [running]) 0x0000000000080000 in ?? ()
  3    Thread 1.3 (CPU#2 [running]) 0x0000000000080000 in ?? ()
* 4    Thread 1.4 (CPU#3 [running]) 0x0000000000080000 in ?? ()
(gdb) c
Continuing.
[Switching to Thread 1.2]

Thread 2 hit Breakpoint 1, 0x0000000000080000 in ?? ()
(gdb) info b
Num     Type           Disp Enb Address            What
1       breakpoint     keep y   0x0000000000080000 
        breakpoint already hit 2 times
2       breakpoint     keep y   0x0000000000080000  thread 2
        stop only in thread 2
        breakpoint already hit 1 time
(gdb) del 1
(gdb) info b
Num     Type           Disp Enb Address            What
2       breakpoint     keep y   0x0000000000080000  thread 2
        stop only in thread 2
        breakpoint already hit 1 time
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, 0x0000000000080000 in ?? ()
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, 0x0000000000080000 in ?? ()
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, 0x0000000000080000 in ?? ()
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, 0x0000000000080000 in ?? ()
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, 0x0000000000080000 in ?? ()
(gdb)

/opt/arm/10/gcc-arm-10.3-2021.07-x86_64-aarch64-none-elf/bin/aarch64-none-elf-gdb wfe.elf -ex 'target remote localhost:1234' -ex 'break *0x80000' -ex 'continue'
GNU gdb (GNU Toolchain for the A-profile Architecture 10.3-2021.07 (arm-10.29)) 10.2.90.20210621-git
Copyright (C) 2021 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
Type "show copying" and "show warranty" for details.
This GDB was configured as "--host=x86_64-pc-linux-gnu --target=aarch64-none-elf".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<https://bugs.linaro.org/>.
Find the GDB manual and other documentation resources online at:
    <http://www.gnu.org/software/gdb/documentation/>.

For help, type "help".
Type "apropos word" to search for commands related to "word"...
Reading symbols from wfe.elf...
Remote debugging using localhost:1234
_start () at wfe.s:3
3       1:      wfe
Breakpoint 1 at 0x80000: file wfe.s, line 3.
Continuing.

Thread 1 hit Breakpoint 1, _start () at wfe.s:3
3       1:      wfe
(gdb) break *0x80000 thread 2
Note: breakpoint 1 (all threads) also set at pc 0x80000.
Breakpoint 2 at 0x80000: file wfe.s, line 3.
(gdb)  info threads
  Id   Target Id                    Frame 
* 1    Thread 1.1 (CPU#0 [running]) _start () at wfe.s:3
  2    Thread 1.2 (CPU#1 [running]) _start () at wfe.s:3
  3    Thread 1.3 (CPU#2 [running]) _start () at wfe.s:3
  4    Thread 1.4 (CPU#3 [running]) _start () at wfe.s:3
(gdb) c
Continuing.
[Switching to Thread 1.2]

Thread 2 hit Breakpoint 1, _start () at wfe.s:3
3       1:      wfe
(gdb) info b
Num     Type           Disp Enb Address            What
1       breakpoint     keep y   0x0000000000080000 wfe.s:3
        breakpoint already hit 2 times
2       breakpoint     keep y   0x0000000000080000 wfe.s:3 thread 2
        stop only in thread 2
        breakpoint already hit 1 time
(gdb) del 1
(gdb) info b
Num     Type           Disp Enb Address            What
2       breakpoint     keep y   0x0000000000080000 wfe.s:3 thread 2
        stop only in thread 2
        breakpoint already hit 1 time
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, _start () at wfe.s:3
3       1:      wfe
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, _start () at wfe.s:3
3       1:      wfe
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, _start () at wfe.s:3
3       1:      wfe
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, _start () at wfe.s:3
3       1:      wfe
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, _start () at wfe.s:3
3       1:      wfe
(gdb)

        .global _start
_start:
1:      wfe
        b 1b

/opt/arm/10/gcc-arm-10.3-2021.07-x86_64-aarch64-none-elf/bin/aarch64-none-elf-gcc -g -ffreestanding -nostdlib -nostartfiles -Wl,-Ttext=0x80000 -o wfe.elf wfe.s

/opt/arm/10/gcc-arm-10.3-2021.07-x86_64-aarch64-none-elf/bin/aarch64-none-elf-objdump -d wfe.elf

wfe.elf:     file format elf64-littleaarch64


Disassembly of section .text:

0000000000080000 <_stack>:
   80000:       d503205f        wfe
   80004:       17ffffff        b       80000 <_stack>

/opt/qemu-6.2.0/bin/qemu-system-aarch64 -M raspi3b -kernel wfe.elf -display none -S -s

/opt/gdb/gdb-10.1-aarch64-elf-x86_64-linux-gnu/bin/aarch64-elf-gdb wfe.elf -ex 'target remote localhost:1234' -ex 'break *0x80000' -ex 'continue'

GNU gdb (GDB) 10.1
Copyright (C) 2020 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
Type "show copying" and "show warranty" for details.
This GDB was configured as "--host=x86_64-linux-gnu --target=aarch64-elf".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<https://www.gnu.org/software/gdb/bugs/>.
Find the GDB manual and other documentation resources online at:
    <http://www.gnu.org/software/gdb/documentation/>.

For help, type "help".
Type "apropos word" to search for commands related to "word".
Remote debugging using localhost:1234
warning: No executable has been specified and target does not support
determining executable automatically.  Try using the "file" command.
0x0000000000080000 in ?? ()
Breakpoint 1 at 0x80000
Continuing.
[Switching to Thread 1.4]

Thread 4 hit Breakpoint 1, 0x0000000000080000 in ?? ()
(gdb) break *0x80000 thread 2
Note: breakpoint 1 (all threads) also set at pc 0x80000.
Breakpoint 2 at 0x80000
(gdb) info threads
  Id   Target Id                    Frame 
  1    Thread 1.1 (CPU#0 [running]) 0x0000000000080000 in ?? ()
  2    Thread 1.2 (CPU#1 [running]) 0x0000000000080000 in ?? ()
  3    Thread 1.3 (CPU#2 [running]) 0x0000000000080000 in ?? ()
* 4    Thread 1.4 (CPU#3 [running]) 0x0000000000080000 in ?? ()
(gdb) c
Continuing.
[Switching to Thread 1.2]

Thread 2 hit Breakpoint 1, 0x0000000000080000 in ?? ()
(gdb) info b
Num     Type           Disp Enb Address            What
1       breakpoint     keep y   0x0000000000080000 
        breakpoint already hit 2 times
2       breakpoint     keep y   0x0000000000080000  thread 2
        stop only in thread 2
        breakpoint already hit 1 time
(gdb) del 1
(gdb) info b
Num     Type           Disp Enb Address            What
2       breakpoint     keep y   0x0000000000080000  thread 2
        stop only in thread 2
        breakpoint already hit 1 time
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, 0x0000000000080000 in ?? ()
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, 0x0000000000080000 in ?? ()
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, 0x0000000000080000 in ?? ()
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, 0x0000000000080000 in ?? ()
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, 0x0000000000080000 in ?? ()
(gdb)

/opt/arm/10/gcc-arm-10.3-2021.07-x86_64-aarch64-none-elf/bin/aarch64-none-elf-gdb wfe.elf -ex 'target remote localhost:1234' -ex 'break *0x80000' -ex 'continue'
GNU gdb (GNU Toolchain for the A-profile Architecture 10.3-2021.07 (arm-10.29)) 10.2.90.20210621-git
Copyright (C) 2021 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
Type "show copying" and "show warranty" for details.
This GDB was configured as "--host=x86_64-pc-linux-gnu --target=aarch64-none-elf".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<https://bugs.linaro.org/>.
Find the GDB manual and other documentation resources online at:
    <http://www.gnu.org/software/gdb/documentation/>.

For help, type "help".
Type "apropos word" to search for commands related to "word"...
Reading symbols from wfe.elf...
Remote debugging using localhost:1234
_start () at wfe.s:3
3       1:      wfe
Breakpoint 1 at 0x80000: file wfe.s, line 3.
Continuing.

Thread 1 hit Breakpoint 1, _start () at wfe.s:3
3       1:      wfe
(gdb) break *0x80000 thread 2
Note: breakpoint 1 (all threads) also set at pc 0x80000.
Breakpoint 2 at 0x80000: file wfe.s, line 3.
(gdb)  info threads
  Id   Target Id                    Frame 
* 1    Thread 1.1 (CPU#0 [running]) _start () at wfe.s:3
  2    Thread 1.2 (CPU#1 [running]) _start () at wfe.s:3
  3    Thread 1.3 (CPU#2 [running]) _start () at wfe.s:3
  4    Thread 1.4 (CPU#3 [running]) _start () at wfe.s:3
(gdb) c
Continuing.
[Switching to Thread 1.2]

Thread 2 hit Breakpoint 1, _start () at wfe.s:3
3       1:      wfe
(gdb) info b
Num     Type           Disp Enb Address            What
1       breakpoint     keep y   0x0000000000080000 wfe.s:3
        breakpoint already hit 2 times
2       breakpoint     keep y   0x0000000000080000 wfe.s:3 thread 2
        stop only in thread 2
        breakpoint already hit 1 time
(gdb) del 1
(gdb) info b
Num     Type           Disp Enb Address            What
2       breakpoint     keep y   0x0000000000080000 wfe.s:3 thread 2
        stop only in thread 2
        breakpoint already hit 1 time
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, _start () at wfe.s:3
3       1:      wfe
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, _start () at wfe.s:3
3       1:      wfe
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, _start () at wfe.s:3
3       1:      wfe
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, _start () at wfe.s:3
3       1:      wfe
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, _start () at wfe.s:3
3       1:      wfe
(gdb)

        .global _start
_start:
1:      wfe
        b 1b

/opt/arm/10/gcc-arm-10.3-2021.07-x86_64-aarch64-none-elf/bin/aarch64-none-elf-gcc -g -ffreestanding -nostdlib -nostartfiles -Wl,-Ttext=0x80000 -o wfe.elf wfe.s

/opt/arm/10/gcc-arm-10.3-2021.07-x86_64-aarch64-none-elf/bin/aarch64-none-elf-objdump -d wfe.elf

wfe.elf:     file format elf64-littleaarch64


Disassembly of section .text:

0000000000080000 <_stack>:
   80000:       d503205f        wfe
   80004:       17ffffff        b       80000 <_stack>

/opt/qemu-6.2.0/bin/qemu-system-aarch64 -M raspi3b -kernel wfe.elf -display none -S -s

/opt/gdb/gdb-10.1-aarch64-elf-x86_64-linux-gnu/bin/aarch64-elf-gdb wfe.elf -ex 'target remote localhost:1234' -ex 'break *0x80000' -ex 'continue'

GNU gdb (GDB) 10.1
Copyright (C) 2020 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
Type "show copying" and "show warranty" for details.
This GDB was configured as "--host=x86_64-linux-gnu --target=aarch64-elf".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<https://www.gnu.org/software/gdb/bugs/>.
Find the GDB manual and other documentation resources online at:
    <http://www.gnu.org/software/gdb/documentation/>.

For help, type "help".
Type "apropos word" to search for commands related to "word".
Remote debugging using localhost:1234
warning: No executable has been specified and target does not support
determining executable automatically.  Try using the "file" command.
0x0000000000080000 in ?? ()
Breakpoint 1 at 0x80000
Continuing.
[Switching to Thread 1.4]

Thread 4 hit Breakpoint 1, 0x0000000000080000 in ?? ()
(gdb) break *0x80000 thread 2
Note: breakpoint 1 (all threads) also set at pc 0x80000.
Breakpoint 2 at 0x80000
(gdb) info threads
  Id   Target Id                    Frame 
  1    Thread 1.1 (CPU#0 [running]) 0x0000000000080000 in ?? ()
  2    Thread 1.2 (CPU#1 [running]) 0x0000000000080000 in ?? ()
  3    Thread 1.3 (CPU#2 [running]) 0x0000000000080000 in ?? ()
* 4    Thread 1.4 (CPU#3 [running]) 0x0000000000080000 in ?? ()
(gdb) c
Continuing.
[Switching to Thread 1.2]

Thread 2 hit Breakpoint 1, 0x0000000000080000 in ?? ()
(gdb) info b
Num     Type           Disp Enb Address            What
1       breakpoint     keep y   0x0000000000080000 
        breakpoint already hit 2 times
2       breakpoint     keep y   0x0000000000080000  thread 2
        stop only in thread 2
        breakpoint already hit 1 time
(gdb) del 1
(gdb) info b
Num     Type           Disp Enb Address            What
2       breakpoint     keep y   0x0000000000080000  thread 2
        stop only in thread 2
        breakpoint already hit 1 time
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, 0x0000000000080000 in ?? ()
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, 0x0000000000080000 in ?? ()
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, 0x0000000000080000 in ?? ()
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, 0x0000000000080000 in ?? ()
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, 0x0000000000080000 in ?? ()
(gdb)

/opt/arm/10/gcc-arm-10.3-2021.07-x86_64-aarch64-none-elf/bin/aarch64-none-elf-gdb wfe.elf -ex 'target remote localhost:1234' -ex 'break *0x80000' -ex 'continue'
GNU gdb (GNU Toolchain for the A-profile Architecture 10.3-2021.07 (arm-10.29)) 10.2.90.20210621-git
Copyright (C) 2021 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
Type "show copying" and "show warranty" for details.
This GDB was configured as "--host=x86_64-pc-linux-gnu --target=aarch64-none-elf".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<https://bugs.linaro.org/>.
Find the GDB manual and other documentation resources online at:
    <http://www.gnu.org/software/gdb/documentation/>.

For help, type "help".
Type "apropos word" to search for commands related to "word"...
Reading symbols from wfe.elf...
Remote debugging using localhost:1234
_start () at wfe.s:3
3       1:      wfe
Breakpoint 1 at 0x80000: file wfe.s, line 3.
Continuing.

Thread 1 hit Breakpoint 1, _start () at wfe.s:3
3       1:      wfe
(gdb) break *0x80000 thread 2
Note: breakpoint 1 (all threads) also set at pc 0x80000.
Breakpoint 2 at 0x80000: file wfe.s, line 3.
(gdb)  info threads
  Id   Target Id                    Frame 
* 1    Thread 1.1 (CPU#0 [running]) _start () at wfe.s:3
  2    Thread 1.2 (CPU#1 [running]) _start () at wfe.s:3
  3    Thread 1.3 (CPU#2 [running]) _start () at wfe.s:3
  4    Thread 1.4 (CPU#3 [running]) _start () at wfe.s:3
(gdb) c
Continuing.
[Switching to Thread 1.2]

Thread 2 hit Breakpoint 1, _start () at wfe.s:3
3       1:      wfe
(gdb) info b
Num     Type           Disp Enb Address            What
1       breakpoint     keep y   0x0000000000080000 wfe.s:3
        breakpoint already hit 2 times
2       breakpoint     keep y   0x0000000000080000 wfe.s:3 thread 2
        stop only in thread 2
        breakpoint already hit 1 time
(gdb) del 1
(gdb) info b
Num     Type           Disp Enb Address            What
2       breakpoint     keep y   0x0000000000080000 wfe.s:3 thread 2
        stop only in thread 2
        breakpoint already hit 1 time
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, _start () at wfe.s:3
3       1:      wfe
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, _start () at wfe.s:3
3       1:      wfe
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, _start () at wfe.s:3
3       1:      wfe
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, _start () at wfe.s:3
3       1:      wfe
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, _start () at wfe.s:3
3       1:      wfe
(gdb)

        .global _start
_start:
1:      wfe
        b 1b

/opt/arm/10/gcc-arm-10.3-2021.07-x86_64-aarch64-none-elf/bin/aarch64-none-elf-gcc -g -ffreestanding -nostdlib -nostartfiles -Wl,-Ttext=0x80000 -o wfe.elf wfe.s

/opt/arm/10/gcc-arm-10.3-2021.07-x86_64-aarch64-none-elf/bin/aarch64-none-elf-objdump -d wfe.elf

wfe.elf:     file format elf64-littleaarch64


Disassembly of section .text:

0000000000080000 <_stack>:
   80000:       d503205f        wfe
   80004:       17ffffff        b       80000 <_stack>

/opt/qemu-6.2.0/bin/qemu-system-aarch64 -M raspi3b -kernel wfe.elf -display none -S -s

/opt/gdb/gdb-10.1-aarch64-elf-x86_64-linux-gnu/bin/aarch64-elf-gdb wfe.elf -ex 'target remote localhost:1234' -ex 'break *0x80000' -ex 'continue'

GNU gdb (GDB) 10.1
Copyright (C) 2020 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
Type "show copying" and "show warranty" for details.
This GDB was configured as "--host=x86_64-linux-gnu --target=aarch64-elf".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<https://www.gnu.org/software/gdb/bugs/>.
Find the GDB manual and other documentation resources online at:
    <http://www.gnu.org/software/gdb/documentation/>.

For help, type "help".
Type "apropos word" to search for commands related to "word".
Remote debugging using localhost:1234
warning: No executable has been specified and target does not support
determining executable automatically.  Try using the "file" command.
0x0000000000080000 in ?? ()
Breakpoint 1 at 0x80000
Continuing.
[Switching to Thread 1.4]

Thread 4 hit Breakpoint 1, 0x0000000000080000 in ?? ()
(gdb) break *0x80000 thread 2
Note: breakpoint 1 (all threads) also set at pc 0x80000.
Breakpoint 2 at 0x80000
(gdb) info threads
  Id   Target Id                    Frame 
  1    Thread 1.1 (CPU#0 [running]) 0x0000000000080000 in ?? ()
  2    Thread 1.2 (CPU#1 [running]) 0x0000000000080000 in ?? ()
  3    Thread 1.3 (CPU#2 [running]) 0x0000000000080000 in ?? ()
* 4    Thread 1.4 (CPU#3 [running]) 0x0000000000080000 in ?? ()
(gdb) c
Continuing.
[Switching to Thread 1.2]

Thread 2 hit Breakpoint 1, 0x0000000000080000 in ?? ()
(gdb) info b
Num     Type           Disp Enb Address            What
1       breakpoint     keep y   0x0000000000080000 
        breakpoint already hit 2 times
2       breakpoint     keep y   0x0000000000080000  thread 2
        stop only in thread 2
        breakpoint already hit 1 time
(gdb) del 1
(gdb) info b
Num     Type           Disp Enb Address            What
2       breakpoint     keep y   0x0000000000080000  thread 2
        stop only in thread 2
        breakpoint already hit 1 time
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, 0x0000000000080000 in ?? ()
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, 0x0000000000080000 in ?? ()
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, 0x0000000000080000 in ?? ()
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, 0x0000000000080000 in ?? ()
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, 0x0000000000080000 in ?? ()
(gdb)

/opt/arm/10/gcc-arm-10.3-2021.07-x86_64-aarch64-none-elf/bin/aarch64-none-elf-gdb wfe.elf -ex 'target remote localhost:1234' -ex 'break *0x80000' -ex 'continue'
GNU gdb (GNU Toolchain for the A-profile Architecture 10.3-2021.07 (arm-10.29)) 10.2.90.20210621-git
Copyright (C) 2021 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
Type "show copying" and "show warranty" for details.
This GDB was configured as "--host=x86_64-pc-linux-gnu --target=aarch64-none-elf".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<https://bugs.linaro.org/>.
Find the GDB manual and other documentation resources online at:
    <http://www.gnu.org/software/gdb/documentation/>.

For help, type "help".
Type "apropos word" to search for commands related to "word"...
Reading symbols from wfe.elf...
Remote debugging using localhost:1234
_start () at wfe.s:3
3       1:      wfe
Breakpoint 1 at 0x80000: file wfe.s, line 3.
Continuing.

Thread 1 hit Breakpoint 1, _start () at wfe.s:3
3       1:      wfe
(gdb) break *0x80000 thread 2
Note: breakpoint 1 (all threads) also set at pc 0x80000.
Breakpoint 2 at 0x80000: file wfe.s, line 3.
(gdb)  info threads
  Id   Target Id                    Frame 
* 1    Thread 1.1 (CPU#0 [running]) _start () at wfe.s:3
  2    Thread 1.2 (CPU#1 [running]) _start () at wfe.s:3
  3    Thread 1.3 (CPU#2 [running]) _start () at wfe.s:3
  4    Thread 1.4 (CPU#3 [running]) _start () at wfe.s:3
(gdb) c
Continuing.
[Switching to Thread 1.2]

Thread 2 hit Breakpoint 1, _start () at wfe.s:3
3       1:      wfe
(gdb) info b
Num     Type           Disp Enb Address            What
1       breakpoint     keep y   0x0000000000080000 wfe.s:3
        breakpoint already hit 2 times
2       breakpoint     keep y   0x0000000000080000 wfe.s:3 thread 2
        stop only in thread 2
        breakpoint already hit 1 time
(gdb) del 1
(gdb) info b
Num     Type           Disp Enb Address            What
2       breakpoint     keep y   0x0000000000080000 wfe.s:3 thread 2
        stop only in thread 2
        breakpoint already hit 1 time
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, _start () at wfe.s:3
3       1:      wfe
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, _start () at wfe.s:3
3       1:      wfe
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, _start () at wfe.s:3
3       1:      wfe
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, _start () at wfe.s:3
3       1:      wfe
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, _start () at wfe.s:3
3       1:      wfe
(gdb)

        .global _start
_start:
1:      wfe
        b 1b

/opt/arm/10/gcc-arm-10.3-2021.07-x86_64-aarch64-none-elf/bin/aarch64-none-elf-gcc -g -ffreestanding -nostdlib -nostartfiles -Wl,-Ttext=0x80000 -o wfe.elf wfe.s

/opt/arm/10/gcc-arm-10.3-2021.07-x86_64-aarch64-none-elf/bin/aarch64-none-elf-objdump -d wfe.elf

wfe.elf:     file format elf64-littleaarch64


Disassembly of section .text:

0000000000080000 <_stack>:
   80000:       d503205f        wfe
   80004:       17ffffff        b       80000 <_stack>

/opt/qemu-6.2.0/bin/qemu-system-aarch64 -M raspi3b -kernel wfe.elf -display none -S -s

/opt/gdb/gdb-10.1-aarch64-elf-x86_64-linux-gnu/bin/aarch64-elf-gdb wfe.elf -ex 'target remote localhost:1234' -ex 'break *0x80000' -ex 'continue'

GNU gdb (GDB) 10.1
Copyright (C) 2020 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
Type "show copying" and "show warranty" for details.
This GDB was configured as "--host=x86_64-linux-gnu --target=aarch64-elf".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<https://www.gnu.org/software/gdb/bugs/>.
Find the GDB manual and other documentation resources online at:
    <http://www.gnu.org/software/gdb/documentation/>.

For help, type "help".
Type "apropos word" to search for commands related to "word".
Remote debugging using localhost:1234
warning: No executable has been specified and target does not support
determining executable automatically.  Try using the "file" command.
0x0000000000080000 in ?? ()
Breakpoint 1 at 0x80000
Continuing.
[Switching to Thread 1.4]

Thread 4 hit Breakpoint 1, 0x0000000000080000 in ?? ()
(gdb) break *0x80000 thread 2
Note: breakpoint 1 (all threads) also set at pc 0x80000.
Breakpoint 2 at 0x80000
(gdb) info threads
  Id   Target Id                    Frame 
  1    Thread 1.1 (CPU#0 [running]) 0x0000000000080000 in ?? ()
  2    Thread 1.2 (CPU#1 [running]) 0x0000000000080000 in ?? ()
  3    Thread 1.3 (CPU#2 [running]) 0x0000000000080000 in ?? ()
* 4    Thread 1.4 (CPU#3 [running]) 0x0000000000080000 in ?? ()
(gdb) c
Continuing.
[Switching to Thread 1.2]

Thread 2 hit Breakpoint 1, 0x0000000000080000 in ?? ()
(gdb) info b
Num     Type           Disp Enb Address            What
1       breakpoint     keep y   0x0000000000080000 
        breakpoint already hit 2 times
2       breakpoint     keep y   0x0000000000080000  thread 2
        stop only in thread 2
        breakpoint already hit 1 time
(gdb) del 1
(gdb) info b
Num     Type           Disp Enb Address            What
2       breakpoint     keep y   0x0000000000080000  thread 2
        stop only in thread 2
        breakpoint already hit 1 time
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, 0x0000000000080000 in ?? ()
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, 0x0000000000080000 in ?? ()
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, 0x0000000000080000 in ?? ()
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, 0x0000000000080000 in ?? ()
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, 0x0000000000080000 in ?? ()
(gdb)

/opt/arm/10/gcc-arm-10.3-2021.07-x86_64-aarch64-none-elf/bin/aarch64-none-elf-gdb wfe.elf -ex 'target remote localhost:1234' -ex 'break *0x80000' -ex 'continue'
GNU gdb (GNU Toolchain for the A-profile Architecture 10.3-2021.07 (arm-10.29)) 10.2.90.20210621-git
Copyright (C) 2021 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
Type "show copying" and "show warranty" for details.
This GDB was configured as "--host=x86_64-pc-linux-gnu --target=aarch64-none-elf".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<https://bugs.linaro.org/>.
Find the GDB manual and other documentation resources online at:
    <http://www.gnu.org/software/gdb/documentation/>.

For help, type "help".
Type "apropos word" to search for commands related to "word"...
Reading symbols from wfe.elf...
Remote debugging using localhost:1234
_start () at wfe.s:3
3       1:      wfe
Breakpoint 1 at 0x80000: file wfe.s, line 3.
Continuing.

Thread 1 hit Breakpoint 1, _start () at wfe.s:3
3       1:      wfe
(gdb) break *0x80000 thread 2
Note: breakpoint 1 (all threads) also set at pc 0x80000.
Breakpoint 2 at 0x80000: file wfe.s, line 3.
(gdb)  info threads
  Id   Target Id                    Frame 
* 1    Thread 1.1 (CPU#0 [running]) _start () at wfe.s:3
  2    Thread 1.2 (CPU#1 [running]) _start () at wfe.s:3
  3    Thread 1.3 (CPU#2 [running]) _start () at wfe.s:3
  4    Thread 1.4 (CPU#3 [running]) _start () at wfe.s:3
(gdb) c
Continuing.
[Switching to Thread 1.2]

Thread 2 hit Breakpoint 1, _start () at wfe.s:3
3       1:      wfe
(gdb) info b
Num     Type           Disp Enb Address            What
1       breakpoint     keep y   0x0000000000080000 wfe.s:3
        breakpoint already hit 2 times
2       breakpoint     keep y   0x0000000000080000 wfe.s:3 thread 2
        stop only in thread 2
        breakpoint already hit 1 time
(gdb) del 1
(gdb) info b
Num     Type           Disp Enb Address            What
2       breakpoint     keep y   0x0000000000080000 wfe.s:3 thread 2
        stop only in thread 2
        breakpoint already hit 1 time
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, _start () at wfe.s:3
3       1:      wfe
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, _start () at wfe.s:3
3       1:      wfe
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, _start () at wfe.s:3
3       1:      wfe
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, _start () at wfe.s:3
3       1:      wfe
(gdb) c
Continuing.

Thread 2 hit Breakpoint 2, _start () at wfe.s:3
3       1:      wfe
(gdb)

How does `Depends on` and `Selected by` work in Kconfig when they conflict

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config SPL
        bool
        depends on SUPPORT_SPL
        prompt "Enable SPL"
        help
          If you want to build SPL as well as the normal image, say Y.

Unable to blink Raspberry Pi LED using bare metal Rust

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{
    "llvm-target": "arm-none-eabihf",
    "target-endian": "little",
    "target-pointer-width": "32",
    "target-c-int-width": "32",
    "os": "none",
    "env": "eabi",
    "vendor": "unknown",
    "arch": "arm",
    "linker-flavor": "ld",
    "linker": "arm-none-eabi-ld",
    "data-layout": "e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64",
    "executables": true,
    "relocation-model": "static",
    "no-compiler-rt": true
}

linked output sections overlap in address

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/* write for machine virt */
ENTRY(_Reset)

MEMORY
{
rm(rx) : ORIGIN = 0x00000000, LENGTH = 0x80000
ram (rwx) : ORIGIN = 0x40000000, LENGTH = 0x40000000
}

SECTIONS
{
 .text : {
  *(.startup)
  *(.text)
  }
 .data : { *(.data) }
 .bss : { *(.bss COMMON) }
 . = ALIGN(8);
 . = . + 0x1000; /* 4kB of stack memory */
 stack_top = .;
}

test.elf:     file format elf64-littleaarch64


Disassembly of section .text:

0000000000000000 <_Reset>:
   0:   58008485    ldr x5, 1090 <stack_top>
   4:   d5184105    msr sp_el0, x5
   8:   94000014    bl  58 <c_entry>
   c:   14000000    b   c <_Reset+0xc>

0000000000000010 <print_uart0>:
  10:   d10043ff    sub sp, sp, #0x10
  14:   f90007e0    str x0, [sp, #8]
  18:   14000008    b   38 <print_uart0+0x28>
  1c:   f94007e0    ldr x0, [sp, #8]
  20:   39400001    ldrb    w1, [x0]
  24:   d2a12000    mov x0, #0x9000000              // #150994944
  28:   b9000001    str w1, [x0]
  2c:   f94007e0    ldr x0, [sp, #8]
  30:   91000400    add x0, x0, #0x1
  34:   f90007e0    str x0, [sp, #8]
  38:   f94007e0    ldr x0, [sp, #8]
  3c:   39400000    ldrb    w0, [x0]
  40:   7100001f    cmp w0, #0x0
  44:   54fffec1    b.ne    1c <print_uart0+0xc>  // b.any
  48:   d503201f    nop
  4c:   d503201f    nop
  50:   910043ff    add sp, sp, #0x10
  54:   d65f03c0    ret

0000000000000058 <c_entry>:
  58:   a9bf7bfd    stp x29, x30, [sp, #-16]!
  5c:   910003fd    mov x29, sp
  60:   90000000    adrp    x0, 0 <_Reset>
  64:   91020000    add x0, x0, #0x80
  68:   97ffffea    bl  10 <print_uart0>
  6c:   d503201f    nop
  70:   a8c17bfd    ldp x29, x30, [sp], #16
  74:   d65f03c0    ret

Disassembly of section .rodata:

0000000000000078 <UART0DR>:
  78:   09000000    .inst   0x09000000 ; undefined
  7c:   00000000    udf #0
  80:   6c6c6548    ldnp    d8, d25, [x10, #-320]
  84:   6f77206f    umlal2  v15.4s, v3.8h, v7.h[3]
  88:   21646c72    .inst   0x21646c72 ; undefined
  8c:   Address 0x000000000000008c is out of bounds.

/* write for machine virt */
ENTRY(_Reset)

MEMORY
{
rm(rx) : ORIGIN = 0x00000000, LENGTH = 0x80000
ram (rwx) : ORIGIN = 0x40000000, LENGTH = 0x40000000
}

SECTIONS
{
 .text : {
  *(.startup)
  *(.text)
  } > ram
 .data : {
  *(.data)
  } > ram
 .bss : { *(.bss COMMON) }
 . = ALIGN(8);
 . = . + 0x1000; /* 4kB of stack memory */
 stack_top = .;
}

test.elf:     file format elf64-littleaarch64


Disassembly of section .text:

0000000040000000 <_Reset>:
    40000000:   58008485    ldr x5, 40001090 <stack_top>
    40000004:   d5184105    msr sp_el0, x5
    40000008:   94000014    bl  40000058 <c_entry>
    4000000c:   14000000    b   4000000c <_Reset+0xc>

0000000040000010 <print_uart0>:
    40000010:   d10043ff    sub sp, sp, #0x10
    40000014:   f90007e0    str x0, [sp, #8]
    40000018:   14000008    b   40000038 <print_uart0+0x28>
    4000001c:   f94007e0    ldr x0, [sp, #8]
    40000020:   39400001    ldrb    w1, [x0]
    40000024:   d2a12000    mov x0, #0x9000000              // #150994944
    40000028:   b9000001    str w1, [x0]
    4000002c:   f94007e0    ldr x0, [sp, #8]
    40000030:   91000400    add x0, x0, #0x1
    40000034:   f90007e0    str x0, [sp, #8]
    40000038:   f94007e0    ldr x0, [sp, #8]
    4000003c:   39400000    ldrb    w0, [x0]
    40000040:   7100001f    cmp w0, #0x0
    40000044:   54fffec1    b.ne    4000001c <print_uart0+0xc>  // b.any
    40000048:   d503201f    nop
    4000004c:   d503201f    nop
    40000050:   910043ff    add sp, sp, #0x10
    40000054:   d65f03c0    ret

0000000040000058 <c_entry>:
    40000058:   a9bf7bfd    stp x29, x30, [sp, #-16]!
    4000005c:   910003fd    mov x29, sp
    40000060:   90000000    adrp    x0, 40000000 <_Reset>
    40000064:   91020000    add x0, x0, #0x80
    40000068:   97ffffea    bl  40000010 <print_uart0>
    4000006c:   d503201f    nop
    40000070:   a8c17bfd    ldp x29, x30, [sp], #16
    40000074:   d65f03c0    ret

Disassembly of section .rodata:

0000000040000078 <UART0DR>:
    40000078:   09000000    .inst   0x09000000 ; undefined
    4000007c:   00000000    udf #0
    40000080:   6c6c6548    ldnp    d8, d25, [x10, #-320]
    40000084:   6f77206f    umlal2  v15.4s, v3.8h, v7.h[3]
    40000088:   21646c72    .inst   0x21646c72 ; undefined
    4000008c:   Address 0x000000004000008c is out of bounds.

/* write for machine virt */
ENTRY(_Reset)

MEMORY
{
rm(rx) : ORIGIN = 0x00000000, LENGTH = 0x80000
ram (rwx) : ORIGIN = 0x40000000, LENGTH = 0x40000000
}

SECTIONS
{
 .text : {
  *(.startup)
  *(.text)
  }
 .data : { *(.data) }
 .bss : { *(.bss COMMON) }
 . = ALIGN(8);
 . = . + 0x1000; /* 4kB of stack memory */
 stack_top = .;
}

test.elf:     file format elf64-littleaarch64


Disassembly of section .text:

0000000000000000 <_Reset>:
   0:   58008485    ldr x5, 1090 <stack_top>
   4:   d5184105    msr sp_el0, x5
   8:   94000014    bl  58 <c_entry>
   c:   14000000    b   c <_Reset+0xc>

0000000000000010 <print_uart0>:
  10:   d10043ff    sub sp, sp, #0x10
  14:   f90007e0    str x0, [sp, #8]
  18:   14000008    b   38 <print_uart0+0x28>
  1c:   f94007e0    ldr x0, [sp, #8]
  20:   39400001    ldrb    w1, [x0]
  24:   d2a12000    mov x0, #0x9000000              // #150994944
  28:   b9000001    str w1, [x0]
  2c:   f94007e0    ldr x0, [sp, #8]
  30:   91000400    add x0, x0, #0x1
  34:   f90007e0    str x0, [sp, #8]
  38:   f94007e0    ldr x0, [sp, #8]
  3c:   39400000    ldrb    w0, [x0]
  40:   7100001f    cmp w0, #0x0
  44:   54fffec1    b.ne    1c <print_uart0+0xc>  // b.any
  48:   d503201f    nop
  4c:   d503201f    nop
  50:   910043ff    add sp, sp, #0x10
  54:   d65f03c0    ret

0000000000000058 <c_entry>:
  58:   a9bf7bfd    stp x29, x30, [sp, #-16]!
  5c:   910003fd    mov x29, sp
  60:   90000000    adrp    x0, 0 <_Reset>
  64:   91020000    add x0, x0, #0x80
  68:   97ffffea    bl  10 <print_uart0>
  6c:   d503201f    nop
  70:   a8c17bfd    ldp x29, x30, [sp], #16
  74:   d65f03c0    ret

Disassembly of section .rodata:

0000000000000078 <UART0DR>:
  78:   09000000    .inst   0x09000000 ; undefined
  7c:   00000000    udf #0
  80:   6c6c6548    ldnp    d8, d25, [x10, #-320]
  84:   6f77206f    umlal2  v15.4s, v3.8h, v7.h[3]
  88:   21646c72    .inst   0x21646c72 ; undefined
  8c:   Address 0x000000000000008c is out of bounds.

/* write for machine virt */
ENTRY(_Reset)

MEMORY
{
rm(rx) : ORIGIN = 0x00000000, LENGTH = 0x80000
ram (rwx) : ORIGIN = 0x40000000, LENGTH = 0x40000000
}

SECTIONS
{
 .text : {
  *(.startup)
  *(.text)
  } > ram
 .data : {
  *(.data)
  } > ram
 .bss : { *(.bss COMMON) }
 . = ALIGN(8);
 . = . + 0x1000; /* 4kB of stack memory */
 stack_top = .;
}

test.elf:     file format elf64-littleaarch64


Disassembly of section .text:

0000000040000000 <_Reset>:
    40000000:   58008485    ldr x5, 40001090 <stack_top>
    40000004:   d5184105    msr sp_el0, x5
    40000008:   94000014    bl  40000058 <c_entry>
    4000000c:   14000000    b   4000000c <_Reset+0xc>

0000000040000010 <print_uart0>:
    40000010:   d10043ff    sub sp, sp, #0x10
    40000014:   f90007e0    str x0, [sp, #8]
    40000018:   14000008    b   40000038 <print_uart0+0x28>
    4000001c:   f94007e0    ldr x0, [sp, #8]
    40000020:   39400001    ldrb    w1, [x0]
    40000024:   d2a12000    mov x0, #0x9000000              // #150994944
    40000028:   b9000001    str w1, [x0]
    4000002c:   f94007e0    ldr x0, [sp, #8]
    40000030:   91000400    add x0, x0, #0x1
    40000034:   f90007e0    str x0, [sp, #8]
    40000038:   f94007e0    ldr x0, [sp, #8]
    4000003c:   39400000    ldrb    w0, [x0]
    40000040:   7100001f    cmp w0, #0x0
    40000044:   54fffec1    b.ne    4000001c <print_uart0+0xc>  // b.any
    40000048:   d503201f    nop
    4000004c:   d503201f    nop
    40000050:   910043ff    add sp, sp, #0x10
    40000054:   d65f03c0    ret

0000000040000058 <c_entry>:
    40000058:   a9bf7bfd    stp x29, x30, [sp, #-16]!
    4000005c:   910003fd    mov x29, sp
    40000060:   90000000    adrp    x0, 40000000 <_Reset>
    40000064:   91020000    add x0, x0, #0x80
    40000068:   97ffffea    bl  40000010 <print_uart0>
    4000006c:   d503201f    nop
    40000070:   a8c17bfd    ldp x29, x30, [sp], #16
    40000074:   d65f03c0    ret

Disassembly of section .rodata:

0000000040000078 <UART0DR>:
    40000078:   09000000    .inst   0x09000000 ; undefined
    4000007c:   00000000    udf #0
    40000080:   6c6c6548    ldnp    d8, d25, [x10, #-320]
    40000084:   6f77206f    umlal2  v15.4s, v3.8h, v7.h[3]
    40000088:   21646c72    .inst   0x21646c72 ; undefined
    4000008c:   Address 0x000000004000008c is out of bounds.

/* write for machine virt */
ENTRY(_Reset)

MEMORY
{
rm(rx) : ORIGIN = 0x00000000, LENGTH = 0x80000
ram (rwx) : ORIGIN = 0x40000000, LENGTH = 0x40000000
}

SECTIONS
{
 .text : {
  *(.startup)
  *(.text)
  }
 .data : { *(.data) }
 .bss : { *(.bss COMMON) }
 . = ALIGN(8);
 . = . + 0x1000; /* 4kB of stack memory */
 stack_top = .;
}

test.elf:     file format elf64-littleaarch64


Disassembly of section .text:

0000000000000000 <_Reset>:
   0:   58008485    ldr x5, 1090 <stack_top>
   4:   d5184105    msr sp_el0, x5
   8:   94000014    bl  58 <c_entry>
   c:   14000000    b   c <_Reset+0xc>

0000000000000010 <print_uart0>:
  10:   d10043ff    sub sp, sp, #0x10
  14:   f90007e0    str x0, [sp, #8]
  18:   14000008    b   38 <print_uart0+0x28>
  1c:   f94007e0    ldr x0, [sp, #8]
  20:   39400001    ldrb    w1, [x0]
  24:   d2a12000    mov x0, #0x9000000              // #150994944
  28:   b9000001    str w1, [x0]
  2c:   f94007e0    ldr x0, [sp, #8]
  30:   91000400    add x0, x0, #0x1
  34:   f90007e0    str x0, [sp, #8]
  38:   f94007e0    ldr x0, [sp, #8]
  3c:   39400000    ldrb    w0, [x0]
  40:   7100001f    cmp w0, #0x0
  44:   54fffec1    b.ne    1c <print_uart0+0xc>  // b.any
  48:   d503201f    nop
  4c:   d503201f    nop
  50:   910043ff    add sp, sp, #0x10
  54:   d65f03c0    ret

0000000000000058 <c_entry>:
  58:   a9bf7bfd    stp x29, x30, [sp, #-16]!
  5c:   910003fd    mov x29, sp
  60:   90000000    adrp    x0, 0 <_Reset>
  64:   91020000    add x0, x0, #0x80
  68:   97ffffea    bl  10 <print_uart0>
  6c:   d503201f    nop
  70:   a8c17bfd    ldp x29, x30, [sp], #16
  74:   d65f03c0    ret

Disassembly of section .rodata:

0000000000000078 <UART0DR>:
  78:   09000000    .inst   0x09000000 ; undefined
  7c:   00000000    udf #0
  80:   6c6c6548    ldnp    d8, d25, [x10, #-320]
  84:   6f77206f    umlal2  v15.4s, v3.8h, v7.h[3]
  88:   21646c72    .inst   0x21646c72 ; undefined
  8c:   Address 0x000000000000008c is out of bounds.

/* write for machine virt */
ENTRY(_Reset)

MEMORY
{
rm(rx) : ORIGIN = 0x00000000, LENGTH = 0x80000
ram (rwx) : ORIGIN = 0x40000000, LENGTH = 0x40000000
}

SECTIONS
{
 .text : {
  *(.startup)
  *(.text)
  } > ram
 .data : {
  *(.data)
  } > ram
 .bss : { *(.bss COMMON) }
 . = ALIGN(8);
 . = . + 0x1000; /* 4kB of stack memory */
 stack_top = .;
}

test.elf:     file format elf64-littleaarch64


Disassembly of section .text:

0000000040000000 <_Reset>:
    40000000:   58008485    ldr x5, 40001090 <stack_top>
    40000004:   d5184105    msr sp_el0, x5
    40000008:   94000014    bl  40000058 <c_entry>
    4000000c:   14000000    b   4000000c <_Reset+0xc>

0000000040000010 <print_uart0>:
    40000010:   d10043ff    sub sp, sp, #0x10
    40000014:   f90007e0    str x0, [sp, #8]
    40000018:   14000008    b   40000038 <print_uart0+0x28>
    4000001c:   f94007e0    ldr x0, [sp, #8]
    40000020:   39400001    ldrb    w1, [x0]
    40000024:   d2a12000    mov x0, #0x9000000              // #150994944
    40000028:   b9000001    str w1, [x0]
    4000002c:   f94007e0    ldr x0, [sp, #8]
    40000030:   91000400    add x0, x0, #0x1
    40000034:   f90007e0    str x0, [sp, #8]
    40000038:   f94007e0    ldr x0, [sp, #8]
    4000003c:   39400000    ldrb    w0, [x0]
    40000040:   7100001f    cmp w0, #0x0
    40000044:   54fffec1    b.ne    4000001c <print_uart0+0xc>  // b.any
    40000048:   d503201f    nop
    4000004c:   d503201f    nop
    40000050:   910043ff    add sp, sp, #0x10
    40000054:   d65f03c0    ret

0000000040000058 <c_entry>:
    40000058:   a9bf7bfd    stp x29, x30, [sp, #-16]!
    4000005c:   910003fd    mov x29, sp
    40000060:   90000000    adrp    x0, 40000000 <_Reset>
    40000064:   91020000    add x0, x0, #0x80
    40000068:   97ffffea    bl  40000010 <print_uart0>
    4000006c:   d503201f    nop
    40000070:   a8c17bfd    ldp x29, x30, [sp], #16
    40000074:   d65f03c0    ret

Disassembly of section .rodata:

0000000040000078 <UART0DR>:
    40000078:   09000000    .inst   0x09000000 ; undefined
    4000007c:   00000000    udf #0
    40000080:   6c6c6548    ldnp    d8, d25, [x10, #-320]
    40000084:   6f77206f    umlal2  v15.4s, v3.8h, v7.h[3]
    40000088:   21646c72    .inst   0x21646c72 ; undefined
    4000008c:   Address 0x000000004000008c is out of bounds.

/* write for machine virt */
ENTRY(_Reset)

MEMORY
{
rm(rx) : ORIGIN = 0x00000000, LENGTH = 0x80000
ram (rwx) : ORIGIN = 0x40000000, LENGTH = 0x40000000
}

SECTIONS
{
 .text : {
  *(.startup)
  *(.text)
  }
 .data : { *(.data) }
 .bss : { *(.bss COMMON) }
 . = ALIGN(8);
 . = . + 0x1000; /* 4kB of stack memory */
 stack_top = .;
}

test.elf:     file format elf64-littleaarch64


Disassembly of section .text:

0000000000000000 <_Reset>:
   0:   58008485    ldr x5, 1090 <stack_top>
   4:   d5184105    msr sp_el0, x5
   8:   94000014    bl  58 <c_entry>
   c:   14000000    b   c <_Reset+0xc>

0000000000000010 <print_uart0>:
  10:   d10043ff    sub sp, sp, #0x10
  14:   f90007e0    str x0, [sp, #8]
  18:   14000008    b   38 <print_uart0+0x28>
  1c:   f94007e0    ldr x0, [sp, #8]
  20:   39400001    ldrb    w1, [x0]
  24:   d2a12000    mov x0, #0x9000000              // #150994944
  28:   b9000001    str w1, [x0]
  2c:   f94007e0    ldr x0, [sp, #8]
  30:   91000400    add x0, x0, #0x1
  34:   f90007e0    str x0, [sp, #8]
  38:   f94007e0    ldr x0, [sp, #8]
  3c:   39400000    ldrb    w0, [x0]
  40:   7100001f    cmp w0, #0x0
  44:   54fffec1    b.ne    1c <print_uart0+0xc>  // b.any
  48:   d503201f    nop
  4c:   d503201f    nop
  50:   910043ff    add sp, sp, #0x10
  54:   d65f03c0    ret

0000000000000058 <c_entry>:
  58:   a9bf7bfd    stp x29, x30, [sp, #-16]!
  5c:   910003fd    mov x29, sp
  60:   90000000    adrp    x0, 0 <_Reset>
  64:   91020000    add x0, x0, #0x80
  68:   97ffffea    bl  10 <print_uart0>
  6c:   d503201f    nop
  70:   a8c17bfd    ldp x29, x30, [sp], #16
  74:   d65f03c0    ret

Disassembly of section .rodata:

0000000000000078 <UART0DR>:
  78:   09000000    .inst   0x09000000 ; undefined
  7c:   00000000    udf #0
  80:   6c6c6548    ldnp    d8, d25, [x10, #-320]
  84:   6f77206f    umlal2  v15.4s, v3.8h, v7.h[3]
  88:   21646c72    .inst   0x21646c72 ; undefined
  8c:   Address 0x000000000000008c is out of bounds.

/* write for machine virt */
ENTRY(_Reset)

MEMORY
{
rm(rx) : ORIGIN = 0x00000000, LENGTH = 0x80000
ram (rwx) : ORIGIN = 0x40000000, LENGTH = 0x40000000
}

SECTIONS
{
 .text : {
  *(.startup)
  *(.text)
  } > ram
 .data : {
  *(.data)
  } > ram
 .bss : { *(.bss COMMON) }
 . = ALIGN(8);
 . = . + 0x1000; /* 4kB of stack memory */
 stack_top = .;
}

test.elf:     file format elf64-littleaarch64


Disassembly of section .text:

0000000040000000 <_Reset>:
    40000000:   58008485    ldr x5, 40001090 <stack_top>
    40000004:   d5184105    msr sp_el0, x5
    40000008:   94000014    bl  40000058 <c_entry>
    4000000c:   14000000    b   4000000c <_Reset+0xc>

0000000040000010 <print_uart0>:
    40000010:   d10043ff    sub sp, sp, #0x10
    40000014:   f90007e0    str x0, [sp, #8]
    40000018:   14000008    b   40000038 <print_uart0+0x28>
    4000001c:   f94007e0    ldr x0, [sp, #8]
    40000020:   39400001    ldrb    w1, [x0]
    40000024:   d2a12000    mov x0, #0x9000000              // #150994944
    40000028:   b9000001    str w1, [x0]
    4000002c:   f94007e0    ldr x0, [sp, #8]
    40000030:   91000400    add x0, x0, #0x1
    40000034:   f90007e0    str x0, [sp, #8]
    40000038:   f94007e0    ldr x0, [sp, #8]
    4000003c:   39400000    ldrb    w0, [x0]
    40000040:   7100001f    cmp w0, #0x0
    40000044:   54fffec1    b.ne    4000001c <print_uart0+0xc>  // b.any
    40000048:   d503201f    nop
    4000004c:   d503201f    nop
    40000050:   910043ff    add sp, sp, #0x10
    40000054:   d65f03c0    ret

0000000040000058 <c_entry>:
    40000058:   a9bf7bfd    stp x29, x30, [sp, #-16]!
    4000005c:   910003fd    mov x29, sp
    40000060:   90000000    adrp    x0, 40000000 <_Reset>
    40000064:   91020000    add x0, x0, #0x80
    40000068:   97ffffea    bl  40000010 <print_uart0>
    4000006c:   d503201f    nop
    40000070:   a8c17bfd    ldp x29, x30, [sp], #16
    40000074:   d65f03c0    ret

Disassembly of section .rodata:

0000000040000078 <UART0DR>:
    40000078:   09000000    .inst   0x09000000 ; undefined
    4000007c:   00000000    udf #0
    40000080:   6c6c6548    ldnp    d8, d25, [x10, #-320]
    40000084:   6f77206f    umlal2  v15.4s, v3.8h, v7.h[3]
    40000088:   21646c72    .inst   0x21646c72 ; undefined
    4000008c:   Address 0x000000004000008c is out of bounds.

How to get an entry point address in binary image file generated by objcopy?

Copy

Download

MEMORY
{
  RAM : ORIGIN = 0x80000000, LENGTH = 16K
  FLASH : ORIGIN = 0x20000000, LENGTH = 16M
}

REGION_ALIAS("REGION_TEXT", FLASH);
REGION_ALIAS("REGION_RODATA", FLASH);
REGION_ALIAS("REGION_DATA", RAM);
REGION_ALIAS("REGION_BSS", RAM);
REGION_ALIAS("REGION_HEAP", RAM);
REGION_ALIAS("REGION_STACK", RAM);

aarch64-none-elf-nm h5-example.elf
0000000042000078 t $d
0000000042000000 t $x
0000000042000080 t $x
00000000420001dc t $x
00000000420001f4 t $x
0000000042000230 B __bss_end__
0000000042000230 B __bss_start__
0000000042000080 T c_entry
000000004200022c D __copy_table_end__
0000000042000220 D __copy_table_start__
0000000042000230 D __data_end__
0000000042000230 D __data_start__
0000000042000230 ? __end__
0000000042000230 B __etext
0000000042000218 T __exidx_end
0000000042000218 T __exidx_start
0000000042000230 d __fini_array_end
0000000042000230 d __fini_array_start
0000000046000230 ? __HeapLimit
0000000004000000 A __HEAP_SIZE
0000000042000230 d __init_array_end
0000000042000230 d __init_array_start
00000000420001f4 T main
0000000042000000 A __RAM_BASE
000000000e000000 A __RAM_SIZE
0000000042000000 T Reset_Handler
0000000000000000 A __ROM_BASE
0000000000000000 A __ROM_SIZE
000000004c000000 ? __StackLimit
0000000004000000 A __STACK_SIZE
0000000050000000 ? __StackTop
00000000420001dc t system_read_CurrentEL
0000000042000230 B __zero_table_end__
0000000042000230 B __zero_table_start__

aarch64-none-elf-nm h5-example-02.elf | grep ' Reset_Handler$'
0000000042000000 T Reset_Handler

aarch64-none-elf-nm h5-example-02.elf | grep ' Reset_Handler$' | cut -d ' ' -f1
0000000042000000

RESET_HANDLER=$(aarch64-none-elf-nm h5-example-02.elf | grep ' Reset_Handler$' | cut -d ' ' -f1)
echo ${RESET_HANDLER}

0000000042000000

echo 0000000042000000 | xxd -r -p > final-image.bin
cat sample1.bin >> final-image.bin

printf "ABCD" > sample1.bin
hexdump -C sample1.bin
00000000  41 42 43 44                                       |ABCD|
00000004

echo 0000000042000000 | xxd -r -p > final-image.bin
hexdump -C final-image.bin

00000000  00 00 00 00 42 00 00 00                           |....B...|
00000008

cat sample1.bin >> final-image.bin
hexdump -C final-image.bin
00000000  00 00 00 00 42 00 00 00  41 42 43 44              |....B...ABCD|
0000000c

#[no_mangle]
pub unsafe extern "C" fn Reset() -> ! {
    let _x = 42;

    // can't return so we go into an infinite loop here
    loop {}
}

// The reset vector, a pointer into the reset handler
#[link_section = ".vector_table.reset_vector"]
#[no_mangle]
pub static RESET_VECTOR: unsafe extern "C" fn() -> ! = Reset;

/* Memory layout of the LM3S6965 microcontroller */
/* 1K = 1 KiBi = 1024 bytes */
MEMORY
{
  FLASH : ORIGIN = 0x00000000, LENGTH = 256K
  RAM : ORIGIN = 0x20000000, LENGTH = 64K
}

/* The entry point is the reset handler */
ENTRY(Reset);

EXTERN(RESET_VECTOR);

SECTIONS
{
  .vector_table ORIGIN(FLASH) :
  {
    /* First entry: initial Stack Pointer value */
    LONG(ORIGIN(RAM) + LENGTH(RAM));

    /* Second entry: reset vector */
    KEEP(*(.vector_table.reset_vector));
  } > FLASH

  .text :
  {
    *(.text .text.*);
  } > FLASH

  /DISCARD/ :
  {
    *(.ARM.exidx .ARM.exidx.*);
  }
}

MEMORY
{
  RAM : ORIGIN = 0x80000000, LENGTH = 16K
  FLASH : ORIGIN = 0x20000000, LENGTH = 16M
}

REGION_ALIAS("REGION_TEXT", FLASH);
REGION_ALIAS("REGION_RODATA", FLASH);
REGION_ALIAS("REGION_DATA", RAM);
REGION_ALIAS("REGION_BSS", RAM);
REGION_ALIAS("REGION_HEAP", RAM);
REGION_ALIAS("REGION_STACK", RAM);

aarch64-none-elf-nm h5-example.elf
0000000042000078 t $d
0000000042000000 t $x
0000000042000080 t $x
00000000420001dc t $x
00000000420001f4 t $x
0000000042000230 B __bss_end__
0000000042000230 B __bss_start__
0000000042000080 T c_entry
000000004200022c D __copy_table_end__
0000000042000220 D __copy_table_start__
0000000042000230 D __data_end__
0000000042000230 D __data_start__
0000000042000230 ? __end__
0000000042000230 B __etext
0000000042000218 T __exidx_end
0000000042000218 T __exidx_start
0000000042000230 d __fini_array_end
0000000042000230 d __fini_array_start
0000000046000230 ? __HeapLimit
0000000004000000 A __HEAP_SIZE
0000000042000230 d __init_array_end
0000000042000230 d __init_array_start
00000000420001f4 T main
0000000042000000 A __RAM_BASE
000000000e000000 A __RAM_SIZE
0000000042000000 T Reset_Handler
0000000000000000 A __ROM_BASE
0000000000000000 A __ROM_SIZE
000000004c000000 ? __StackLimit
0000000004000000 A __STACK_SIZE
0000000050000000 ? __StackTop
00000000420001dc t system_read_CurrentEL
0000000042000230 B __zero_table_end__
0000000042000230 B __zero_table_start__

aarch64-none-elf-nm h5-example-02.elf | grep ' Reset_Handler$'
0000000042000000 T Reset_Handler

aarch64-none-elf-nm h5-example-02.elf | grep ' Reset_Handler$' | cut -d ' ' -f1
0000000042000000

RESET_HANDLER=$(aarch64-none-elf-nm h5-example-02.elf | grep ' Reset_Handler$' | cut -d ' ' -f1)
echo ${RESET_HANDLER}

0000000042000000

echo 0000000042000000 | xxd -r -p > final-image.bin
cat sample1.bin >> final-image.bin

printf "ABCD" > sample1.bin
hexdump -C sample1.bin
00000000  41 42 43 44                                       |ABCD|
00000004

echo 0000000042000000 | xxd -r -p > final-image.bin
hexdump -C final-image.bin

00000000  00 00 00 00 42 00 00 00                           |....B...|
00000008

cat sample1.bin >> final-image.bin
hexdump -C final-image.bin
00000000  00 00 00 00 42 00 00 00  41 42 43 44              |....B...ABCD|
0000000c

#[no_mangle]
pub unsafe extern "C" fn Reset() -> ! {
    let _x = 42;

    // can't return so we go into an infinite loop here
    loop {}
}

// The reset vector, a pointer into the reset handler
#[link_section = ".vector_table.reset_vector"]
#[no_mangle]
pub static RESET_VECTOR: unsafe extern "C" fn() -> ! = Reset;

/* Memory layout of the LM3S6965 microcontroller */
/* 1K = 1 KiBi = 1024 bytes */
MEMORY
{
  FLASH : ORIGIN = 0x00000000, LENGTH = 256K
  RAM : ORIGIN = 0x20000000, LENGTH = 64K
}

/* The entry point is the reset handler */
ENTRY(Reset);

EXTERN(RESET_VECTOR);

SECTIONS
{
  .vector_table ORIGIN(FLASH) :
  {
    /* First entry: initial Stack Pointer value */
    LONG(ORIGIN(RAM) + LENGTH(RAM));

    /* Second entry: reset vector */
    KEEP(*(.vector_table.reset_vector));
  } > FLASH

  .text :
  {
    *(.text .text.*);
  } > FLASH

  /DISCARD/ :
  {
    *(.ARM.exidx .ARM.exidx.*);
  }
}

MEMORY
{
  RAM : ORIGIN = 0x80000000, LENGTH = 16K
  FLASH : ORIGIN = 0x20000000, LENGTH = 16M
}

REGION_ALIAS("REGION_TEXT", FLASH);
REGION_ALIAS("REGION_RODATA", FLASH);
REGION_ALIAS("REGION_DATA", RAM);
REGION_ALIAS("REGION_BSS", RAM);
REGION_ALIAS("REGION_HEAP", RAM);
REGION_ALIAS("REGION_STACK", RAM);

aarch64-none-elf-nm h5-example.elf
0000000042000078 t $d
0000000042000000 t $x
0000000042000080 t $x
00000000420001dc t $x
00000000420001f4 t $x
0000000042000230 B __bss_end__
0000000042000230 B __bss_start__
0000000042000080 T c_entry
000000004200022c D __copy_table_end__
0000000042000220 D __copy_table_start__
0000000042000230 D __data_end__
0000000042000230 D __data_start__
0000000042000230 ? __end__
0000000042000230 B __etext
0000000042000218 T __exidx_end
0000000042000218 T __exidx_start
0000000042000230 d __fini_array_end
0000000042000230 d __fini_array_start
0000000046000230 ? __HeapLimit
0000000004000000 A __HEAP_SIZE
0000000042000230 d __init_array_end
0000000042000230 d __init_array_start
00000000420001f4 T main
0000000042000000 A __RAM_BASE
000000000e000000 A __RAM_SIZE
0000000042000000 T Reset_Handler
0000000000000000 A __ROM_BASE
0000000000000000 A __ROM_SIZE
000000004c000000 ? __StackLimit
0000000004000000 A __STACK_SIZE
0000000050000000 ? __StackTop
00000000420001dc t system_read_CurrentEL
0000000042000230 B __zero_table_end__
0000000042000230 B __zero_table_start__

aarch64-none-elf-nm h5-example-02.elf | grep ' Reset_Handler$'
0000000042000000 T Reset_Handler

aarch64-none-elf-nm h5-example-02.elf | grep ' Reset_Handler$' | cut -d ' ' -f1
0000000042000000

RESET_HANDLER=$(aarch64-none-elf-nm h5-example-02.elf | grep ' Reset_Handler$' | cut -d ' ' -f1)
echo ${RESET_HANDLER}

0000000042000000

echo 0000000042000000 | xxd -r -p > final-image.bin
cat sample1.bin >> final-image.bin

printf "ABCD" > sample1.bin
hexdump -C sample1.bin
00000000  41 42 43 44                                       |ABCD|
00000004

echo 0000000042000000 | xxd -r -p > final-image.bin
hexdump -C final-image.bin

00000000  00 00 00 00 42 00 00 00                           |....B...|
00000008

cat sample1.bin >> final-image.bin
hexdump -C final-image.bin
00000000  00 00 00 00 42 00 00 00  41 42 43 44              |....B...ABCD|
0000000c

#[no_mangle]
pub unsafe extern "C" fn Reset() -> ! {
    let _x = 42;

    // can't return so we go into an infinite loop here
    loop {}
}

// The reset vector, a pointer into the reset handler
#[link_section = ".vector_table.reset_vector"]
#[no_mangle]
pub static RESET_VECTOR: unsafe extern "C" fn() -> ! = Reset;

/* Memory layout of the LM3S6965 microcontroller */
/* 1K = 1 KiBi = 1024 bytes */
MEMORY
{
  FLASH : ORIGIN = 0x00000000, LENGTH = 256K
  RAM : ORIGIN = 0x20000000, LENGTH = 64K
}

/* The entry point is the reset handler */
ENTRY(Reset);

EXTERN(RESET_VECTOR);

SECTIONS
{
  .vector_table ORIGIN(FLASH) :
  {
    /* First entry: initial Stack Pointer value */
    LONG(ORIGIN(RAM) + LENGTH(RAM));

    /* Second entry: reset vector */
    KEEP(*(.vector_table.reset_vector));
  } > FLASH

  .text :
  {
    *(.text .text.*);
  } > FLASH

  /DISCARD/ :
  {
    *(.ARM.exidx .ARM.exidx.*);
  }
}

MEMORY
{
  RAM : ORIGIN = 0x80000000, LENGTH = 16K
  FLASH : ORIGIN = 0x20000000, LENGTH = 16M
}

REGION_ALIAS("REGION_TEXT", FLASH);
REGION_ALIAS("REGION_RODATA", FLASH);
REGION_ALIAS("REGION_DATA", RAM);
REGION_ALIAS("REGION_BSS", RAM);
REGION_ALIAS("REGION_HEAP", RAM);
REGION_ALIAS("REGION_STACK", RAM);

aarch64-none-elf-nm h5-example.elf
0000000042000078 t $d
0000000042000000 t $x
0000000042000080 t $x
00000000420001dc t $x
00000000420001f4 t $x
0000000042000230 B __bss_end__
0000000042000230 B __bss_start__
0000000042000080 T c_entry
000000004200022c D __copy_table_end__
0000000042000220 D __copy_table_start__
0000000042000230 D __data_end__
0000000042000230 D __data_start__
0000000042000230 ? __end__
0000000042000230 B __etext
0000000042000218 T __exidx_end
0000000042000218 T __exidx_start
0000000042000230 d __fini_array_end
0000000042000230 d __fini_array_start
0000000046000230 ? __HeapLimit
0000000004000000 A __HEAP_SIZE
0000000042000230 d __init_array_end
0000000042000230 d __init_array_start
00000000420001f4 T main
0000000042000000 A __RAM_BASE
000000000e000000 A __RAM_SIZE
0000000042000000 T Reset_Handler
0000000000000000 A __ROM_BASE
0000000000000000 A __ROM_SIZE
000000004c000000 ? __StackLimit
0000000004000000 A __STACK_SIZE
0000000050000000 ? __StackTop
00000000420001dc t system_read_CurrentEL
0000000042000230 B __zero_table_end__
0000000042000230 B __zero_table_start__

aarch64-none-elf-nm h5-example-02.elf | grep ' Reset_Handler$'
0000000042000000 T Reset_Handler

aarch64-none-elf-nm h5-example-02.elf | grep ' Reset_Handler$' | cut -d ' ' -f1
0000000042000000

RESET_HANDLER=$(aarch64-none-elf-nm h5-example-02.elf | grep ' Reset_Handler$' | cut -d ' ' -f1)
echo ${RESET_HANDLER}

0000000042000000

echo 0000000042000000 | xxd -r -p > final-image.bin
cat sample1.bin >> final-image.bin

printf "ABCD" > sample1.bin
hexdump -C sample1.bin
00000000  41 42 43 44                                       |ABCD|
00000004

echo 0000000042000000 | xxd -r -p > final-image.bin
hexdump -C final-image.bin

00000000  00 00 00 00 42 00 00 00                           |....B...|
00000008

cat sample1.bin >> final-image.bin
hexdump -C final-image.bin
00000000  00 00 00 00 42 00 00 00  41 42 43 44              |....B...ABCD|
0000000c

#[no_mangle]
pub unsafe extern "C" fn Reset() -> ! {
    let _x = 42;

    // can't return so we go into an infinite loop here
    loop {}
}

// The reset vector, a pointer into the reset handler
#[link_section = ".vector_table.reset_vector"]
#[no_mangle]
pub static RESET_VECTOR: unsafe extern "C" fn() -> ! = Reset;

/* Memory layout of the LM3S6965 microcontroller */
/* 1K = 1 KiBi = 1024 bytes */
MEMORY
{
  FLASH : ORIGIN = 0x00000000, LENGTH = 256K
  RAM : ORIGIN = 0x20000000, LENGTH = 64K
}

/* The entry point is the reset handler */
ENTRY(Reset);

EXTERN(RESET_VECTOR);

SECTIONS
{
  .vector_table ORIGIN(FLASH) :
  {
    /* First entry: initial Stack Pointer value */
    LONG(ORIGIN(RAM) + LENGTH(RAM));

    /* Second entry: reset vector */
    KEEP(*(.vector_table.reset_vector));
  } > FLASH

  .text :
  {
    *(.text .text.*);
  } > FLASH

  /DISCARD/ :
  {
    *(.ARM.exidx .ARM.exidx.*);
  }
}

MEMORY
{
  RAM : ORIGIN = 0x80000000, LENGTH = 16K
  FLASH : ORIGIN = 0x20000000, LENGTH = 16M
}

REGION_ALIAS("REGION_TEXT", FLASH);
REGION_ALIAS("REGION_RODATA", FLASH);
REGION_ALIAS("REGION_DATA", RAM);
REGION_ALIAS("REGION_BSS", RAM);
REGION_ALIAS("REGION_HEAP", RAM);
REGION_ALIAS("REGION_STACK", RAM);

aarch64-none-elf-nm h5-example.elf
0000000042000078 t $d
0000000042000000 t $x
0000000042000080 t $x
00000000420001dc t $x
00000000420001f4 t $x
0000000042000230 B __bss_end__
0000000042000230 B __bss_start__
0000000042000080 T c_entry
000000004200022c D __copy_table_end__
0000000042000220 D __copy_table_start__
0000000042000230 D __data_end__
0000000042000230 D __data_start__
0000000042000230 ? __end__
0000000042000230 B __etext
0000000042000218 T __exidx_end
0000000042000218 T __exidx_start
0000000042000230 d __fini_array_end
0000000042000230 d __fini_array_start
0000000046000230 ? __HeapLimit
0000000004000000 A __HEAP_SIZE
0000000042000230 d __init_array_end
0000000042000230 d __init_array_start
00000000420001f4 T main
0000000042000000 A __RAM_BASE
000000000e000000 A __RAM_SIZE
0000000042000000 T Reset_Handler
0000000000000000 A __ROM_BASE
0000000000000000 A __ROM_SIZE
000000004c000000 ? __StackLimit
0000000004000000 A __STACK_SIZE
0000000050000000 ? __StackTop
00000000420001dc t system_read_CurrentEL
0000000042000230 B __zero_table_end__
0000000042000230 B __zero_table_start__

aarch64-none-elf-nm h5-example-02.elf | grep ' Reset_Handler$'
0000000042000000 T Reset_Handler

aarch64-none-elf-nm h5-example-02.elf | grep ' Reset_Handler$' | cut -d ' ' -f1
0000000042000000

RESET_HANDLER=$(aarch64-none-elf-nm h5-example-02.elf | grep ' Reset_Handler$' | cut -d ' ' -f1)
echo ${RESET_HANDLER}

0000000042000000

echo 0000000042000000 | xxd -r -p > final-image.bin
cat sample1.bin >> final-image.bin

printf "ABCD" > sample1.bin
hexdump -C sample1.bin
00000000  41 42 43 44                                       |ABCD|
00000004

echo 0000000042000000 | xxd -r -p > final-image.bin
hexdump -C final-image.bin

00000000  00 00 00 00 42 00 00 00                           |....B...|
00000008

cat sample1.bin >> final-image.bin
hexdump -C final-image.bin
00000000  00 00 00 00 42 00 00 00  41 42 43 44              |....B...ABCD|
0000000c

#[no_mangle]
pub unsafe extern "C" fn Reset() -> ! {
    let _x = 42;

    // can't return so we go into an infinite loop here
    loop {}
}

// The reset vector, a pointer into the reset handler
#[link_section = ".vector_table.reset_vector"]
#[no_mangle]
pub static RESET_VECTOR: unsafe extern "C" fn() -> ! = Reset;

/* Memory layout of the LM3S6965 microcontroller */
/* 1K = 1 KiBi = 1024 bytes */
MEMORY
{
  FLASH : ORIGIN = 0x00000000, LENGTH = 256K
  RAM : ORIGIN = 0x20000000, LENGTH = 64K
}

/* The entry point is the reset handler */
ENTRY(Reset);

EXTERN(RESET_VECTOR);

SECTIONS
{
  .vector_table ORIGIN(FLASH) :
  {
    /* First entry: initial Stack Pointer value */
    LONG(ORIGIN(RAM) + LENGTH(RAM));

    /* Second entry: reset vector */
    KEEP(*(.vector_table.reset_vector));
  } > FLASH

  .text :
  {
    *(.text .text.*);
  } > FLASH

  /DISCARD/ :
  {
    *(.ARM.exidx .ARM.exidx.*);
  }
}

MEMORY
{
  RAM : ORIGIN = 0x80000000, LENGTH = 16K
  FLASH : ORIGIN = 0x20000000, LENGTH = 16M
}

REGION_ALIAS("REGION_TEXT", FLASH);
REGION_ALIAS("REGION_RODATA", FLASH);
REGION_ALIAS("REGION_DATA", RAM);
REGION_ALIAS("REGION_BSS", RAM);
REGION_ALIAS("REGION_HEAP", RAM);
REGION_ALIAS("REGION_STACK", RAM);

aarch64-none-elf-nm h5-example.elf
0000000042000078 t $d
0000000042000000 t $x
0000000042000080 t $x
00000000420001dc t $x
00000000420001f4 t $x
0000000042000230 B __bss_end__
0000000042000230 B __bss_start__
0000000042000080 T c_entry
000000004200022c D __copy_table_end__
0000000042000220 D __copy_table_start__
0000000042000230 D __data_end__
0000000042000230 D __data_start__
0000000042000230 ? __end__
0000000042000230 B __etext
0000000042000218 T __exidx_end
0000000042000218 T __exidx_start
0000000042000230 d __fini_array_end
0000000042000230 d __fini_array_start
0000000046000230 ? __HeapLimit
0000000004000000 A __HEAP_SIZE
0000000042000230 d __init_array_end
0000000042000230 d __init_array_start
00000000420001f4 T main
0000000042000000 A __RAM_BASE
000000000e000000 A __RAM_SIZE
0000000042000000 T Reset_Handler
0000000000000000 A __ROM_BASE
0000000000000000 A __ROM_SIZE
000000004c000000 ? __StackLimit
0000000004000000 A __STACK_SIZE
0000000050000000 ? __StackTop
00000000420001dc t system_read_CurrentEL
0000000042000230 B __zero_table_end__
0000000042000230 B __zero_table_start__

aarch64-none-elf-nm h5-example-02.elf | grep ' Reset_Handler$'
0000000042000000 T Reset_Handler

aarch64-none-elf-nm h5-example-02.elf | grep ' Reset_Handler$' | cut -d ' ' -f1
0000000042000000

RESET_HANDLER=$(aarch64-none-elf-nm h5-example-02.elf | grep ' Reset_Handler$' | cut -d ' ' -f1)
echo ${RESET_HANDLER}

0000000042000000

echo 0000000042000000 | xxd -r -p > final-image.bin
cat sample1.bin >> final-image.bin

printf "ABCD" > sample1.bin
hexdump -C sample1.bin
00000000  41 42 43 44                                       |ABCD|
00000004

echo 0000000042000000 | xxd -r -p > final-image.bin
hexdump -C final-image.bin

00000000  00 00 00 00 42 00 00 00                           |....B...|
00000008

cat sample1.bin >> final-image.bin
hexdump -C final-image.bin
00000000  00 00 00 00 42 00 00 00  41 42 43 44              |....B...ABCD|
0000000c

#[no_mangle]
pub unsafe extern "C" fn Reset() -> ! {
    let _x = 42;

    // can't return so we go into an infinite loop here
    loop {}
}

// The reset vector, a pointer into the reset handler
#[link_section = ".vector_table.reset_vector"]
#[no_mangle]
pub static RESET_VECTOR: unsafe extern "C" fn() -> ! = Reset;

/* Memory layout of the LM3S6965 microcontroller */
/* 1K = 1 KiBi = 1024 bytes */
MEMORY
{
  FLASH : ORIGIN = 0x00000000, LENGTH = 256K
  RAM : ORIGIN = 0x20000000, LENGTH = 64K
}

/* The entry point is the reset handler */
ENTRY(Reset);

EXTERN(RESET_VECTOR);

SECTIONS
{
  .vector_table ORIGIN(FLASH) :
  {
    /* First entry: initial Stack Pointer value */
    LONG(ORIGIN(RAM) + LENGTH(RAM));

    /* Second entry: reset vector */
    KEEP(*(.vector_table.reset_vector));
  } > FLASH

  .text :
  {
    *(.text .text.*);
  } > FLASH

  /DISCARD/ :
  {
    *(.ARM.exidx .ARM.exidx.*);
  }
}

MEMORY
{
  RAM : ORIGIN = 0x80000000, LENGTH = 16K
  FLASH : ORIGIN = 0x20000000, LENGTH = 16M
}

REGION_ALIAS("REGION_TEXT", FLASH);
REGION_ALIAS("REGION_RODATA", FLASH);
REGION_ALIAS("REGION_DATA", RAM);
REGION_ALIAS("REGION_BSS", RAM);
REGION_ALIAS("REGION_HEAP", RAM);
REGION_ALIAS("REGION_STACK", RAM);

aarch64-none-elf-nm h5-example.elf
0000000042000078 t $d
0000000042000000 t $x
0000000042000080 t $x
00000000420001dc t $x
00000000420001f4 t $x
0000000042000230 B __bss_end__
0000000042000230 B __bss_start__
0000000042000080 T c_entry
000000004200022c D __copy_table_end__
0000000042000220 D __copy_table_start__
0000000042000230 D __data_end__
0000000042000230 D __data_start__
0000000042000230 ? __end__
0000000042000230 B __etext
0000000042000218 T __exidx_end
0000000042000218 T __exidx_start
0000000042000230 d __fini_array_end
0000000042000230 d __fini_array_start
0000000046000230 ? __HeapLimit
0000000004000000 A __HEAP_SIZE
0000000042000230 d __init_array_end
0000000042000230 d __init_array_start
00000000420001f4 T main
0000000042000000 A __RAM_BASE
000000000e000000 A __RAM_SIZE
0000000042000000 T Reset_Handler
0000000000000000 A __ROM_BASE
0000000000000000 A __ROM_SIZE
000000004c000000 ? __StackLimit
0000000004000000 A __STACK_SIZE
0000000050000000 ? __StackTop
00000000420001dc t system_read_CurrentEL
0000000042000230 B __zero_table_end__
0000000042000230 B __zero_table_start__

aarch64-none-elf-nm h5-example-02.elf | grep ' Reset_Handler$'
0000000042000000 T Reset_Handler

aarch64-none-elf-nm h5-example-02.elf | grep ' Reset_Handler$' | cut -d ' ' -f1
0000000042000000

RESET_HANDLER=$(aarch64-none-elf-nm h5-example-02.elf | grep ' Reset_Handler$' | cut -d ' ' -f1)
echo ${RESET_HANDLER}

0000000042000000

echo 0000000042000000 | xxd -r -p > final-image.bin
cat sample1.bin >> final-image.bin

printf "ABCD" > sample1.bin
hexdump -C sample1.bin
00000000  41 42 43 44                                       |ABCD|
00000004

echo 0000000042000000 | xxd -r -p > final-image.bin
hexdump -C final-image.bin

00000000  00 00 00 00 42 00 00 00                           |....B...|
00000008

cat sample1.bin >> final-image.bin
hexdump -C final-image.bin
00000000  00 00 00 00 42 00 00 00  41 42 43 44              |....B...ABCD|
0000000c

#[no_mangle]
pub unsafe extern "C" fn Reset() -> ! {
    let _x = 42;

    // can't return so we go into an infinite loop here
    loop {}
}

// The reset vector, a pointer into the reset handler
#[link_section = ".vector_table.reset_vector"]
#[no_mangle]
pub static RESET_VECTOR: unsafe extern "C" fn() -> ! = Reset;

/* Memory layout of the LM3S6965 microcontroller */
/* 1K = 1 KiBi = 1024 bytes */
MEMORY
{
  FLASH : ORIGIN = 0x00000000, LENGTH = 256K
  RAM : ORIGIN = 0x20000000, LENGTH = 64K
}

/* The entry point is the reset handler */
ENTRY(Reset);

EXTERN(RESET_VECTOR);

SECTIONS
{
  .vector_table ORIGIN(FLASH) :
  {
    /* First entry: initial Stack Pointer value */
    LONG(ORIGIN(RAM) + LENGTH(RAM));

    /* Second entry: reset vector */
    KEEP(*(.vector_table.reset_vector));
  } > FLASH

  .text :
  {
    *(.text .text.*);
  } > FLASH

  /DISCARD/ :
  {
    *(.ARM.exidx .ARM.exidx.*);
  }
}

MEMORY
{
  RAM : ORIGIN = 0x80000000, LENGTH = 16K
  FLASH : ORIGIN = 0x20000000, LENGTH = 16M
}

REGION_ALIAS("REGION_TEXT", FLASH);
REGION_ALIAS("REGION_RODATA", FLASH);
REGION_ALIAS("REGION_DATA", RAM);
REGION_ALIAS("REGION_BSS", RAM);
REGION_ALIAS("REGION_HEAP", RAM);
REGION_ALIAS("REGION_STACK", RAM);

aarch64-none-elf-nm h5-example.elf
0000000042000078 t $d
0000000042000000 t $x
0000000042000080 t $x
00000000420001dc t $x
00000000420001f4 t $x
0000000042000230 B __bss_end__
0000000042000230 B __bss_start__
0000000042000080 T c_entry
000000004200022c D __copy_table_end__
0000000042000220 D __copy_table_start__
0000000042000230 D __data_end__
0000000042000230 D __data_start__
0000000042000230 ? __end__
0000000042000230 B __etext
0000000042000218 T __exidx_end
0000000042000218 T __exidx_start
0000000042000230 d __fini_array_end
0000000042000230 d __fini_array_start
0000000046000230 ? __HeapLimit
0000000004000000 A __HEAP_SIZE
0000000042000230 d __init_array_end
0000000042000230 d __init_array_start
00000000420001f4 T main
0000000042000000 A __RAM_BASE
000000000e000000 A __RAM_SIZE
0000000042000000 T Reset_Handler
0000000000000000 A __ROM_BASE
0000000000000000 A __ROM_SIZE
000000004c000000 ? __StackLimit
0000000004000000 A __STACK_SIZE
0000000050000000 ? __StackTop
00000000420001dc t system_read_CurrentEL
0000000042000230 B __zero_table_end__
0000000042000230 B __zero_table_start__

aarch64-none-elf-nm h5-example-02.elf | grep ' Reset_Handler$'
0000000042000000 T Reset_Handler

aarch64-none-elf-nm h5-example-02.elf | grep ' Reset_Handler$' | cut -d ' ' -f1
0000000042000000

RESET_HANDLER=$(aarch64-none-elf-nm h5-example-02.elf | grep ' Reset_Handler$' | cut -d ' ' -f1)
echo ${RESET_HANDLER}

0000000042000000

echo 0000000042000000 | xxd -r -p > final-image.bin
cat sample1.bin >> final-image.bin

printf "ABCD" > sample1.bin
hexdump -C sample1.bin
00000000  41 42 43 44                                       |ABCD|
00000004

echo 0000000042000000 | xxd -r -p > final-image.bin
hexdump -C final-image.bin

00000000  00 00 00 00 42 00 00 00                           |....B...|
00000008

cat sample1.bin >> final-image.bin
hexdump -C final-image.bin
00000000  00 00 00 00 42 00 00 00  41 42 43 44              |....B...ABCD|
0000000c

#[no_mangle]
pub unsafe extern "C" fn Reset() -> ! {
    let _x = 42;

    // can't return so we go into an infinite loop here
    loop {}
}

// The reset vector, a pointer into the reset handler
#[link_section = ".vector_table.reset_vector"]
#[no_mangle]
pub static RESET_VECTOR: unsafe extern "C" fn() -> ! = Reset;

/* Memory layout of the LM3S6965 microcontroller */
/* 1K = 1 KiBi = 1024 bytes */
MEMORY
{
  FLASH : ORIGIN = 0x00000000, LENGTH = 256K
  RAM : ORIGIN = 0x20000000, LENGTH = 64K
}

/* The entry point is the reset handler */
ENTRY(Reset);

EXTERN(RESET_VECTOR);

SECTIONS
{
  .vector_table ORIGIN(FLASH) :
  {
    /* First entry: initial Stack Pointer value */
    LONG(ORIGIN(RAM) + LENGTH(RAM));

    /* Second entry: reset vector */
    KEEP(*(.vector_table.reset_vector));
  } > FLASH

  .text :
  {
    *(.text .text.*);
  } > FLASH

  /DISCARD/ :
  {
    *(.ARM.exidx .ARM.exidx.*);
  }
}

MEMORY
{
  RAM : ORIGIN = 0x80000000, LENGTH = 16K
  FLASH : ORIGIN = 0x20000000, LENGTH = 16M
}

REGION_ALIAS("REGION_TEXT", FLASH);
REGION_ALIAS("REGION_RODATA", FLASH);
REGION_ALIAS("REGION_DATA", RAM);
REGION_ALIAS("REGION_BSS", RAM);
REGION_ALIAS("REGION_HEAP", RAM);
REGION_ALIAS("REGION_STACK", RAM);

aarch64-none-elf-nm h5-example.elf
0000000042000078 t $d
0000000042000000 t $x
0000000042000080 t $x
00000000420001dc t $x
00000000420001f4 t $x
0000000042000230 B __bss_end__
0000000042000230 B __bss_start__
0000000042000080 T c_entry
000000004200022c D __copy_table_end__
0000000042000220 D __copy_table_start__
0000000042000230 D __data_end__
0000000042000230 D __data_start__
0000000042000230 ? __end__
0000000042000230 B __etext
0000000042000218 T __exidx_end
0000000042000218 T __exidx_start
0000000042000230 d __fini_array_end
0000000042000230 d __fini_array_start
0000000046000230 ? __HeapLimit
0000000004000000 A __HEAP_SIZE
0000000042000230 d __init_array_end
0000000042000230 d __init_array_start
00000000420001f4 T main
0000000042000000 A __RAM_BASE
000000000e000000 A __RAM_SIZE
0000000042000000 T Reset_Handler
0000000000000000 A __ROM_BASE
0000000000000000 A __ROM_SIZE
000000004c000000 ? __StackLimit
0000000004000000 A __STACK_SIZE
0000000050000000 ? __StackTop
00000000420001dc t system_read_CurrentEL
0000000042000230 B __zero_table_end__
0000000042000230 B __zero_table_start__

aarch64-none-elf-nm h5-example-02.elf | grep ' Reset_Handler$'
0000000042000000 T Reset_Handler

aarch64-none-elf-nm h5-example-02.elf | grep ' Reset_Handler$' | cut -d ' ' -f1
0000000042000000

RESET_HANDLER=$(aarch64-none-elf-nm h5-example-02.elf | grep ' Reset_Handler$' | cut -d ' ' -f1)
echo ${RESET_HANDLER}

0000000042000000

echo 0000000042000000 | xxd -r -p > final-image.bin
cat sample1.bin >> final-image.bin

printf "ABCD" > sample1.bin
hexdump -C sample1.bin
00000000  41 42 43 44                                       |ABCD|
00000004

echo 0000000042000000 | xxd -r -p > final-image.bin
hexdump -C final-image.bin

00000000  00 00 00 00 42 00 00 00                           |....B...|
00000008

cat sample1.bin >> final-image.bin
hexdump -C final-image.bin
00000000  00 00 00 00 42 00 00 00  41 42 43 44              |....B...ABCD|
0000000c

#[no_mangle]
pub unsafe extern "C" fn Reset() -> ! {
    let _x = 42;

    // can't return so we go into an infinite loop here
    loop {}
}

// The reset vector, a pointer into the reset handler
#[link_section = ".vector_table.reset_vector"]
#[no_mangle]
pub static RESET_VECTOR: unsafe extern "C" fn() -> ! = Reset;

/* Memory layout of the LM3S6965 microcontroller */
/* 1K = 1 KiBi = 1024 bytes */
MEMORY
{
  FLASH : ORIGIN = 0x00000000, LENGTH = 256K
  RAM : ORIGIN = 0x20000000, LENGTH = 64K
}

/* The entry point is the reset handler */
ENTRY(Reset);

EXTERN(RESET_VECTOR);

SECTIONS
{
  .vector_table ORIGIN(FLASH) :
  {
    /* First entry: initial Stack Pointer value */
    LONG(ORIGIN(RAM) + LENGTH(RAM));

    /* Second entry: reset vector */
    KEEP(*(.vector_table.reset_vector));
  } > FLASH

  .text :
  {
    *(.text .text.*);
  } > FLASH

  /DISCARD/ :
  {
    *(.ARM.exidx .ARM.exidx.*);
  }
}

ARM64 (Cortex-A53) - GNU Assembler - GIC register: unknown or missing system register name

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// write system register  ICC_SRE_EL1 (s3_0_c12_c12_5) with specified value.
static inline void system_write_ICC_SRE_EL1(uint64_t val)
{
    asm volatile("msr s3_0_c12_c12_5 , %0" : : "r" (val));
}

// read system register value ICC_SRE_EL1 (s3_0_c12_c12_5).
static inline uint64_t system_read_ICC_SRE_EL1(void)
{
    uint64_t val;
    asm volatile("mrs %0, s3_0_c12_c12_5" : "=r" (val));
    return val;
}

// write system register  ICC_SRE_EL2 (s3_4_c12_c9_5) with specified value.
static inline void system_write_ICC_SRE_EL2(uint64_t val)
{
    asm volatile("msr s3_4_c12_c9_5 , %0" : : "r" (val));
}

// read system register value ICC_SRE_EL2 (s3_4_c12_c9_5).
static inline uint64_t system_read_ICC_SRE_EL2(void)
{
    uint64_t val;
    asm volatile("mrs %0, s3_4_c12_c9_5" : "=r" (val));
    return val;
}

// write system register  ICC_SRE_EL3 (s3_6_c12_c12_5) with specified value.
static inline void system_write_ICC_SRE_EL3(uint64_t val)
{
    asm volatile("msr s3_6_c12_c12_5 , %0" : : "r" (val));
}

// read system register value ICC_SRE_EL3 (s3_6_c12_c12_5).
static inline uint64_t system_read_ICC_SRE_EL3(void)
{
    uint64_t val;
    asm volatile("mrs %0, s3_6_c12_c12_5" : "=r" (val));
    return val;
}

/* TODO there is one more issues need to be resolved
   1. handle cpu-implementation-defined system registers.  */
const aarch64_sys_reg aarch64_sys_regs [] =
{
  { "spsr_el1",         CPEN_(0,C0,0),  0 }, /* = spsr_svc */
  { "spsr_el12",    CPEN_ (5, C0, 0), F_ARCHEXT },
  { "elr_el1",          CPEN_(0,C0,1),  0 },
  { "elr_el12", CPEN_ (5, C0, 1), F_ARCHEXT },
  { "sp_el0",           CPEN_(0,C1,0),  0 },
  { "spsel",            CPEN_(0,C2,0),  0 },
  { "daif",             CPEN_(3,C2,1),  0 },
  { "currentel",        CPEN_(0,C2,2),  F_REG_READ }, /* RO */
  { "pan",      CPEN_(0,C2,3),  F_ARCHEXT },
  { "uao",      CPEN_ (0, C2, 4), F_ARCHEXT },
  { "nzcv",             CPEN_(3,C2,0),  0 },
  { "ssbs",     CPEN_(3,C2,6),  F_ARCHEXT },
  { "fpcr",             CPEN_(3,C4,0),  0 },
  { "fpsr",             CPEN_(3,C4,1),  0 },
  { "dspsr_el0",        CPEN_(3,C5,0),  0 },
  { "dlr_el0",          CPEN_(3,C5,1),  0 },
  { "spsr_el2",         CPEN_(4,C0,0),  0 }, /* = spsr_hyp */
  { "elr_el2",          CPEN_(4,C0,1),  0 },
  { "sp_el1",           CPEN_(4,C1,0),  0 },
  { "spsr_irq",         CPEN_(4,C3,0),  0 },
  { "spsr_abt",         CPEN_(4,C3,1),  0 },
  { "spsr_und",         CPEN_(4,C3,2),  0 },
  { "spsr_fiq",         CPEN_(4,C3,3),  0 },
  { "spsr_el3",         CPEN_(6,C0,0),  0 },
  { "elr_el3",          CPEN_(6,C0,1),  0 },
  { "sp_el2",           CPEN_(6,C1,0),  0 },
  ...

// write system register  ICC_SRE_EL1 (s3_0_c12_c12_5) with specified value.
static inline void system_write_ICC_SRE_EL1(uint64_t val)
{
    asm volatile("msr s3_0_c12_c12_5 , %0" : : "r" (val));
}

// read system register value ICC_SRE_EL1 (s3_0_c12_c12_5).
static inline uint64_t system_read_ICC_SRE_EL1(void)
{
    uint64_t val;
    asm volatile("mrs %0, s3_0_c12_c12_5" : "=r" (val));
    return val;
}

// write system register  ICC_SRE_EL2 (s3_4_c12_c9_5) with specified value.
static inline void system_write_ICC_SRE_EL2(uint64_t val)
{
    asm volatile("msr s3_4_c12_c9_5 , %0" : : "r" (val));
}

// read system register value ICC_SRE_EL2 (s3_4_c12_c9_5).
static inline uint64_t system_read_ICC_SRE_EL2(void)
{
    uint64_t val;
    asm volatile("mrs %0, s3_4_c12_c9_5" : "=r" (val));
    return val;
}

// write system register  ICC_SRE_EL3 (s3_6_c12_c12_5) with specified value.
static inline void system_write_ICC_SRE_EL3(uint64_t val)
{
    asm volatile("msr s3_6_c12_c12_5 , %0" : : "r" (val));
}

// read system register value ICC_SRE_EL3 (s3_6_c12_c12_5).
static inline uint64_t system_read_ICC_SRE_EL3(void)
{
    uint64_t val;
    asm volatile("mrs %0, s3_6_c12_c12_5" : "=r" (val));
    return val;
}

/* TODO there is one more issues need to be resolved
   1. handle cpu-implementation-defined system registers.  */
const aarch64_sys_reg aarch64_sys_regs [] =
{
  { "spsr_el1",         CPEN_(0,C0,0),  0 }, /* = spsr_svc */
  { "spsr_el12",    CPEN_ (5, C0, 0), F_ARCHEXT },
  { "elr_el1",          CPEN_(0,C0,1),  0 },
  { "elr_el12", CPEN_ (5, C0, 1), F_ARCHEXT },
  { "sp_el0",           CPEN_(0,C1,0),  0 },
  { "spsel",            CPEN_(0,C2,0),  0 },
  { "daif",             CPEN_(3,C2,1),  0 },
  { "currentel",        CPEN_(0,C2,2),  F_REG_READ }, /* RO */
  { "pan",      CPEN_(0,C2,3),  F_ARCHEXT },
  { "uao",      CPEN_ (0, C2, 4), F_ARCHEXT },
  { "nzcv",             CPEN_(3,C2,0),  0 },
  { "ssbs",     CPEN_(3,C2,6),  F_ARCHEXT },
  { "fpcr",             CPEN_(3,C4,0),  0 },
  { "fpsr",             CPEN_(3,C4,1),  0 },
  { "dspsr_el0",        CPEN_(3,C5,0),  0 },
  { "dlr_el0",          CPEN_(3,C5,1),  0 },
  { "spsr_el2",         CPEN_(4,C0,0),  0 }, /* = spsr_hyp */
  { "elr_el2",          CPEN_(4,C0,1),  0 },
  { "sp_el1",           CPEN_(4,C1,0),  0 },
  { "spsr_irq",         CPEN_(4,C3,0),  0 },
  { "spsr_abt",         CPEN_(4,C3,1),  0 },
  { "spsr_und",         CPEN_(4,C3,2),  0 },
  { "spsr_fiq",         CPEN_(4,C3,3),  0 },
  { "spsr_el3",         CPEN_(6,C0,0),  0 },
  { "elr_el3",          CPEN_(6,C0,1),  0 },
  { "sp_el2",           CPEN_(6,C1,0),  0 },
  ...

See all related Code Snippets

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QUESTION

How do I really disable all rustc optimizations?

Asked 2022-Mar-11 at 12:38

I'm trying to learn assembly through compiling Rust. I have found a way to compile Rust code to binary machine code and be able to objdump it to view the assembly. However if I write the following:

#![no_main]

#[link_section = ".text.entry"]
#[no_mangle]
pub extern "C" fn _start() -> ! {
    let a: u64 = 4;
    let b: u64 = 7;
    let c: u64 = a * b;
    
    loop {}
}

The assembly I get is:

0000000000000000 <.data>:
   0:   1101                    addi    sp,sp,-32
   2:   4511                    li      a0,4
   4:   e42a                    sd      a0,8(sp)
   6:   451d                    li      a0,7
   8:   e82a                    sd      a0,16(sp)
   a:   4571                    li      a0,28
   c:   ec2a                    sd      a0,24(sp)
   e:   a009                    j       0x10
  10:   a001                    j       0x10

So it looks like rust is collapsing the mul to a constant. I'm using the following compile options:

Cargo.toml:

[profile.dev]
opt-level = 0
mir-opt-level = 0

Is there a way to stop Rust from optimizing this?

The LLVM emitted looks like this:

; Function Attrs: noreturn nounwind
define dso_local void @_start() unnamed_addr #0 section ".text.entry" !dbg !22 {
start:
  %c.dbg.spill = alloca i64, align 8
  %b.dbg.spill = alloca i64, align 8
  %a.dbg.spill = alloca i64, align 8
  store i64 4, i64* %a.dbg.spill, align 8, !dbg !36
  call void @llvm.dbg.declare(metadata i64* %a.dbg.spill, metadata !28, metadata !DIExpression()), !dbg !37
  store i64 7, i64* %b.dbg.spill, align 8, !dbg !38
  call void @llvm.dbg.declare(metadata i64* %b.dbg.spill, metadata !31, metadata !DIExpression()), !dbg !39
  store i64 28, i64* %c.dbg.spill, align 8, !dbg !40
  call void @llvm.dbg.declare(metadata i64* %c.dbg.spill, metadata !33, metadata !DIExpression()), !dbg !41

So it looks like the optimization is before the LLVM pass.

$ rustc --version                                                                                                                                           
rustc 1.60.0-nightly (c5c610aad 2022-02-14)

Command to build:

RUSTFLAGS="--emit=llvm-bc" cargo build --target riscv64imac-unknown-none-elf --no-default-features

build.rs

fn main() {
    println!("cargo:rerun-if-changed=build.rs");
    println!("cargo:rustc-link-arg=-Tlink.ld");
}

link.ld

ENTRY(_start)
SECTIONS {
  .text : { *(.text); *(.text.*) }
}

ANSWER

Answered 2022-Mar-11 at 12:38

There is one compiler pass before the generation of LLVM-IR, which is the generation of MIR, the Rust intermediate representation. If you emit this for the given code with a command such as this one:

cargo rustc -- --emit mir

You will see in the .mir file generated that the optimization already took place there.

fn _start() -> ! {
    let mut _0: !;                       // return place in scope 0 at src\main.rs:5:31: 5:32
    let _1: u64;                         // in scope 0 at src\main.rs:6:9: 6:10
    scope 1 {
        debug a => _1;                   // in scope 1 at src\main.rs:6:9: 6:10
        let _2: u64;                     // in scope 1 at src\main.rs:7:9: 7:10
        scope 2 {
            debug b => _2;               // in scope 2 at src\main.rs:7:9: 7:10
            let _3: u64;                 // in scope 2 at src\main.rs:8:9: 8:10
            scope 3 {
                debug c => _3;           // in scope 3 at src\main.rs:8:9: 8:10
            }
        }
    }

    bb0: {
        _1 = const 4_u64;                // scope 0 at src\main.rs:6:18: 6:19
        _2 = const 7_u64;                // scope 1 at src\main.rs:7:18: 7:19
        _3 = const 28_u64;               // scope 2 at src\main.rs:8:18: 8:23
        goto -> bb1;                     // scope 3 at src\main.rs:10:5: 10:12
    }

    bb1: {
        goto -> bb1;                     // scope 3 at src\main.rs:10:5: 10:12
    }
}

This is happening because the mir-opt-level option currently only exists as an unstable compiler option. It is not available as a profile property in Cargo. Set it manually on a direct call to the compiler:

cargo rustc -- -Z mir-opt-level=0 --emir mir

And this optimization will disappear:

fn _start() -> ! {
    let mut _0: !;                       // return place in scope 0 at src\main.rs:5:31: 5:32
    let mut _1: !;                       // in scope 0 at src\main.rs:5:33: 11:2
    let _2: u64;                         // in scope 0 at src\main.rs:6:9: 6:10
    let mut _5: u64;                     // in scope 0 at src\main.rs:8:18: 8:19
    let mut _6: u64;                     // in scope 0 at src\main.rs:8:22: 8:23
    let mut _7: (u64, bool);             // in scope 0 at src\main.rs:8:18: 8:23
    let mut _8: !;                       // in scope 0 at src\main.rs:10:5: 10:12
    let mut _9: ();                      // in scope 0 at src\main.rs:5:1: 11:2
    scope 1 {
        debug a => _2;                   // in scope 1 at src\main.rs:6:9: 6:10
        let _3: u64;                     // in scope 1 at src\main.rs:7:9: 7:10
        scope 2 {
            debug b => _3;               // in scope 2 at src\main.rs:7:9: 7:10
            let _4: u64;                 // in scope 2 at src\main.rs:8:9: 8:10
            scope 3 {
                debug c => _4;           // in scope 3 at src\main.rs:8:9: 8:10
            }
        }
    }

    bb0: {
        StorageLive(_1);                 // scope 0 at src\main.rs:5:33: 11:2
        StorageLive(_2);                 // scope 0 at src\main.rs:6:9: 6:10
        _2 = const 4_u64;                // scope 0 at src\main.rs:6:18: 6:19
        StorageLive(_3);                 // scope 1 at src\main.rs:7:9: 7:10
        _3 = const 7_u64;                // scope 1 at src\main.rs:7:18: 7:19
        StorageLive(_4);                 // scope 2 at src\main.rs:8:9: 8:10
        StorageLive(_5);                 // scope 2 at src\main.rs:8:18: 8:19
        _5 = _2;                         // scope 2 at src\main.rs:8:18: 8:19
        StorageLive(_6);                 // scope 2 at src\main.rs:8:22: 8:23
        _6 = _3;                         // scope 2 at src\main.rs:8:22: 8:23
        _7 = CheckedMul(_5, _6);         // scope 2 at src\main.rs:8:18: 8:23
        assert(!move (_7.1: bool), "attempt to compute `{} * {}`, which would overflow", move _5, move _6) -> bb1; // scope 2 at src\main.rs:8:18: 8:23
    }

    bb1: {
        _4 = move (_7.0: u64);           // scope 2 at src\main.rs:8:18: 8:23
        StorageDead(_6);                 // scope 2 at src\main.rs:8:22: 8:23
        StorageDead(_5);                 // scope 2 at src\main.rs:8:22: 8:23
        StorageLive(_8);                 // scope 3 at src\main.rs:10:5: 10:12
        goto -> bb2;                     // scope 3 at src\main.rs:10:5: 10:12
    }

    bb2: {
        _9 = const ();                   // scope 3 at src\main.rs:10:10: 10:12
        goto -> bb2;                     // scope 3 at src\main.rs:10:5: 10:12
    }
}

And this is probably as far as you can go without touching LLVM directly. Some optimisations in specific parts of the code can also be prevented through constructs such as black_box.

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