Zig 0.17.0-dev (Split by item)

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syscall0

powerpc.syscall0

pub fn syscall0(
    number: SYS,
) u32

File

lib/std/os/linux/powerpc.zig:7

Code

pub fn syscall0(
    number: SYS,
) u32 {
    // r0 is both an input register and a clobber. musl and glibc achieve this with
    // a "+" constraint, which isn't supported in Zig, so instead we separately list
    // r0 as both an input and an output. (Listing it as an input and a clobber would
    // cause the C backend to emit invalid code; see #25209.)
    var r0_out: u32 = undefined;
    return asm volatile (
        \\ sc
        \\ bns+ 1f
        \\ neg 3, 3
        \\ 1:
        : [ret] "={r3}" (-> u32),
          [r0_out] "={r0}" (r0_out),
        : [number] "{r0}" (@backingInt(number)),
        : .{ .memory = true, .cr0 = true, .r4 = true, .r5 = true, .r6 = true, .r7 = true, .r8 = true, .r9 = true, .r10 = true, .r11 = true, .r12 = true, .ctr = true, .xer = true });
}