https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89021
Bug ID: 89021
Summary: Implement mmintrin.h in SSE
Product: gcc
Version: 9.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: target
Assignee: unassigned at gcc dot gnu.org
Reporter: hjl.tools at gmail dot com
CC: crazylht at gmail dot com, ubizjak at gmail dot com,
xuepeng.guo at intel dot com
Target Milestone: ---
Target: x86-64
On x86-64, __m64 is returned and passed in XMM registers. We generate
[hjl@gnu-cfl-1 pr88828]$ cat i.c
#include <mmintrin.h>
__m64
foo (__m64 x, __m64 y)
{
return _m_packssdw (x, y);
}
[hjl@gnu-cfl-1 pr88828]$ gcc -S -O2 i.c -march=haswell
[hjl@gnu-cfl-1 pr88828]$ cat i.s
.file "i.c"
.text
.p2align 4,,15
.globl foo
.type foo, @function
foo:
.LFB129:
.cfi_startproc
movdq2q %xmm0, %mm0
movdq2q %xmm1, %mm1
packssdw %mm1, %mm0
movq2dq %mm0, %xmm0
ret
.cfi_endproc
.LFE129:
.size foo, .-foo
.ident "GCC: (GNU) 8.2.1 20190109 (Red Hat 8.2.1-7)"
.section .note.GNU-stack,"",@progbits
[hjl@gnu-cfl-1 pr88828]$
We can generate
packssdw %xmm1, %xmm0
ret
instead.
