https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90263
--- Comment #18 from Wilco <wilco at gcc dot gnu.org> ---
(In reply to Martin Liška from comment #14)
> Created attachment 46262 [details]
> Patch candidate
>
> Patch candidate that handles:
>
> $ cat ~/Programming/testcases/mempcpy.c
> int *mempcopy2 (int *p, int *q, long n)
> {
> return __builtin_mempcpy (p, q, n);
> }
>
> $ ./xgcc -B. -O2 -S ~/Programming/testcases/mempcpy.c -o/dev/stdout
> ...
> mempcopy2:
> .LFB0:
> .cfi_startproc
> pushq %rbx
> .cfi_def_cfa_offset 16
> .cfi_offset 3, -16
> movq %rdx, %rbx
> call memcpy
> addq %rbx, %rax
> popq %rbx
> .cfi_def_cfa_offset 8
> ret
> ...
>
> There's a single failing test: gcc.dg/20050503-1.c
On AArch64 it calls mempcpy but memcpy on x86, which is the wrong way around...
- if (retmode == RETURN_END && target != const0_rtx)
+ if (!TARGET_HAS_FAST_MEMPCPY_ROUTINE && retmode == RETURN_END && target !=
const0_rtx)
When I uncomment this, it uses memcpy. Also:
+ TARGET_HAS_FAST_MEMPCPY_ROUTINE
+ && retmode == RETURN_END_MINUS_ONE,
+ &is_move_done);
Should that be RETURN_END? And is_move_done isn't used, is that right?
