https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110273
Bug ID: 110273
Summary: i686-w64-mingw32 with -march=znver4 generates AVX
instructions without stack alignment
Product: gcc
Version: 13.1.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: target
Assignee: unassigned at gcc dot gnu.org
Reporter: zfigura at codeweavers dot com
CC: amonakov at gcc dot gnu.org
Target Milestone: ---
Created attachment 55334
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=55334&action=edit
offending source file
Found with Wine.
I've attached a C file that's a minimal-ish reproducer.
I don't currently have a machine with gcc 13.1.0, so I did this using
godbolt.org's "MinGW gcc 13.1.0" target, with "-m32". Full compiler flags are
"-m32 -march=znver4 -O2".
The generated output begins
pushl %ebp
vpxor %xmm0, %xmm0, %xmm0
movl %esp, %ebp
subl $424, %esp
vmovdqa %xmm0, 16(%esp)
which is broken. Using -march=znver3 instead will generate the same vmovdqa
instruction, but align the stack first:
pushl %ebp
vpxor %xmm0, %xmm0, %xmm0
movl %esp, %ebp
andl $-16, %esp
subl $416, %esp
leal 36(%esp), %eax
movl $380, 8(%esp)
movl $0, 4(%esp)
vmovdqa %xmm0, 16(%esp)
