https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120201
H.J. Lu <hjl.tools at gmail dot com> changed:
What |Removed |Added
----------------------------------------------------------------------------
Component|target |sanitizer
CC| |dodji at gcc dot gnu.org,
| |dvyukov at gcc dot gnu.org,
| |jakub at gcc dot gnu.org,
| |kcc at gcc dot gnu.org
--- Comment #4 from H.J. Lu <hjl.tools at gmail dot com> ---
On master branch, the stack is properly aligned:
main:
.LASANPC2:
.LFB2:
.cfi_startproc
pushq %rbp
.cfi_def_cfa_offset 16
.cfi_offset 6, -16
movq %rsp, %rbp
.cfi_def_cfa_register 6
pushq %r15
pushq %r14
pushq %r13
pushq %r12
pushq %rbx
andq $-64, %rsp <<<<<<<< Stack realignment
subq $576, %rsp
.cfi_offset 15, -24
.cfi_offset 14, -32
.cfi_offset 13, -40
.cfi_offset 12, -48
.cfi_offset 3, -56
movl __asan_option_detect_stack_use_after_return(%rip), %eax
leaq 96(%rsp), %r12
...
movl $480, %edi
call __asan_stack_malloc_3 <<< sanitizer allocates aligned stack
gdb) next
33 jne .L115
(gdb)
899 movl $480, %edi
(gdb)
900 call __asan_stack_malloc_3
(gdb)
901 testq %rax, %rax
(gdb) next
902 cmovne %rax, %r12
(gdb)
903 jmp .L1
(gdb) p/x $r12
$8 = 0x7bfff5200000
(gdb)
testq %rax, %rax
cmovne %rax, %r12
jmp .L1
...
vmovdqa64 32(%r12), %zmm0
^^^ R12 + 32 isn't 64 byte aligned.
