------- Comment #3 from ramana at gcc dot gnu dot org 2010-08-03 14:14 -------
Created an attachment (id=21375)
--> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=21375&action=view)
testcase.
The difference is in the case with and without debug info. With the attached
pre-processed file and with and without -g you can see differences in code
generated between -g and no -g . The command line options I've used to generate
this code are in a cross-compiler.
-O2
and
-O2 -g
The difference in code generated in the case of debug info is with cprop
deciding to constant propagate a value of 0 into one of the instructions in the
case of with debug info and not without debug info.
We can see the difference in the case of tree-vect-data-refs.i with a cross
compiler to arm-linux-gnueabi with and without the command line options as
mentioned above.
Sorry about the largish testcase but I've not been able to reduce the testcase
further . The difference in code generation happens in
vect_analyze_data_ref_accesses - the one on the left is without debug and the
one on the right is the case with debug info for the same basic block.
.L947: .L947:
add ip, sp, #32 add ip, sp, #32
ldmia ip, {fp-ip} ldmia ip, {fp-ip}
ldr r4, [sp, #40] ldr r4, [sp, #40]
orrs ip, fp, ip orrs ip, fp, ip
> moveq r0, #0
ldreq lr, [sp, #80] ldreq lr, [sp, #80]
> streq r0, [sp, #36]
ldr r0, [r4, #4] ldr r0, [r4, #4]
streq lr, [sp, #32] streq lr, [sp, #32]
bl vinfo_for_stmt.isra.11 bl vinfo_for_stmt.isra.11
ldr r7, [sp, #32] ldr r7, [sp, #32]
str r7, [r0, #76] str r7, [r0, #76]
mov r0, #9 mov r0, #9
bl vect_print_dump_info bl vect_print_dump_info
cmp r0, #0 cmp r0, #0
bne .L1025 bne .L1025
--
ramana at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
Attachment #21370|0 |1
is obsolete| |
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45162
