>>108000999
>>>zig
const std = @import("std");
// 1. ABI Control: explicitly setting calling convention
// options: .C, .Stdcall, .Naked, .Signal, etc.
fn kernel_entry() callconv(.Naked) void {
asm volatile (
\\ mov $0x1, %rax
\\ ret
);
}
pub fn main() void {
var x: i32 = std.crypto.random.int(i32);
// 2. Branch Hints: 'std.builtin.expect' tells the optimizer
// that 'cond' is extremely likely to equal 'true'.
// this emits the llvm.expect intrinsic.
if (std.builtin.expect(x > 5, true)) {
// fast path: compiler arranges this block to be strictly sequential
} else {
// slow path: likely pushed to a different instruction page (cold)
}
// 3. Readable/Writable Ranges (via Alignment types)
// this pointer carries its alignment proof in its type signature.
// the compiler knows it can use aligned vector load instructions.
var y: i32 = 100;
const ptr: *align(16) i32 = @alignCast(&y);
}
>>>rust
use std::num::NonZeroU32;
// 1. ABI Control: strictly defining the binary interface
#[no_mangle]
pub extern "C" fn my_c_callback(arg: i32) -> i32 {
arg + 1
}
// 2. Ranges / Layout:
// 'NonZeroU32' gives the compiler a "niche optimization" hint,
// allowing 'Option<NonZeroU32>' to be the same size as 'u32'.
struct LowLevelPack {
id: NonZeroU32,
// #[repr(C)] forces C-compatible memory layout, disabling field reordering
data: [u8; 16],
}
fn process_data(data: &LowLevelPack) {
if data.id.get() == 9999 {
handle_rare_error();
}
}
// 3. Branch Hints (Stable Way):
// marking a function as 'cold' tells the optimizer
// that calls to this function are unlikely.
#[cold]
fn handle_rare_error() {
// the compiler moves this code away from the hot path
}
