------- Comment #4 from rguenth at gcc dot gnu dot org 2008-06-27 09:31 -------
The vectorizer creates an unaligned access. -O -ftree-vectorize reproduces it.
_GLOBAL__I_foo:
.LFB10:
xorps %xmm0, %xmm0
movaps %xmm0, foo+4(%rip)
movl $foo+20, %eax
movaps %xmm0, (%rax)
movaps %xmm0, 16(%rax)
ret
.globl foo
.bss
.align 32
.type foo, @object
.size foo, 52
base_address: &foo
offset from base address: 0
constant offset from base address: 4
step: 12
aligned to: 128
base_object: ((struct vector *) &foo)->x
symbol tag: SMT.10
the base object looks wrong (or doesn't it include the constant offset?)
In the end it looks like the vectorizer simply ignores the first field of
the struct.
--
rguenth at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |irar at il dot ibm dot com,
| |rguenth at gcc dot gnu dot
| |org, spop at gcc dot gnu dot
| |org
Status|UNCONFIRMED |NEW
Component|c++ |tree-optimization
Ever Confirmed|0 |1
Keywords| |wrong-code
Known to work|3.4.6 4.0.1 4.2.3 |3.4.6 4.0.1 4.1.2 4.2.4
Priority|P3 |P1
Last reconfirmed|0000-00-00 00:00:00 |2008-06-27 09:31:54
date| |
Summary|segfault in global |[4.3/4.4 Regression]
|constructor with -O3 |segfault in global
| |constructor with -O3
Target Milestone|--- |4.3.2
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36648
