https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81736
--- Comment #4 from H.J. Lu <hjl.tools at gmail dot com> ---
Another weird code with -fno-omit-frame-pointer:
[hjl@gnu-6 pr59501]$ cat k.i
typedef int v8si __attribute__ ((vector_size (32)));
void
foo (v8si *idx, v8si *out_start, v8si *out_end,
v8si *regions)
{
v8si base = regions[3];
*out_start = base;
*out_end = base;
}
[hjl@gnu-6 pr59501]$ make k.s
/export/build/gnu/gcc/build-x86_64-linux/gcc/xgcc
-B/export/build/gnu/gcc/build-x86_64-linux/gcc/ -O -fno-omit-frame-pointer
-mavx -S k.i
[hjl@gnu-6 pr59501]$ cat k.s
.file "k.i"
.text
.globl foo
.type foo, @function
foo:
.LFB0:
.cfi_startproc
pushq %rbp
.cfi_def_cfa_offset 16
.cfi_offset 6, -16
movq %rsp, %rbp
.cfi_def_cfa_register 6
andq $-32, %rsp <<<<<<<<<<<< Why do we realign stack?
vmovdqa 96(%rcx), %ymm0
vmovdqa %ymm0, (%rsi)
vmovdqa %ymm0, (%rdx)
leave
.cfi_def_cfa 7, 8
ret
.cfi_endproc
.LFE0:
.size foo, .-foo
.ident "GCC: (GNU) 8.0.0 20170807 (experimental)"
.section .note.GNU-stack,"",@progbits
[hjl@gnu-6 pr59501]$
