On 27/11/15 14:09, Richard Biener wrote:
On Fri, Nov 27, 2015 at 10:44 AM, Kyrill Tkachov <kyrylo.tkac...@arm.com> wrote:
On 26/11/15 16:54, Kyrill Tkachov wrote:
On 26/11/15 16:49, Bernd Schmidt wrote:
On 11/26/2015 05:45 PM, Kyrill Tkachov wrote:
that doesn't help, punt. */
- modified_in_a = emit_a != NULL_RTX && modified_in_p (orig_b, emit_a);
if (tmp_b && then_bb)
{
These bits I thought would be part of a followup patch (which would also
guard against single_set problems), and as I mentioned I'd rather have a
checking assert.
Yes, you're right. I have the checking_assert statement in the followup
that I've been testing.
I'll move the deletion of these two statements there as well to minimise
the changes to this patch.
I'll move these bits to that patch, re-build cc1 and commit.
Here it is.
I'm committing this to trunk.
I think this causes
FAIL: gcc.c-torture/execute/20050124-1.c -O2 (internal compiler error)
FAIL: gcc.c-torture/execute/20050124-1.c -O2 (test for excess errors)
WARNING: gcc.c-torture/execute/20050124-1.c -O2 compilation failed to produce
executable
FAIL: gcc.c-torture/execute/20050124-1.c -O2 -flto -fno-use-linker-plugin -flt
o-partition=none (internal compiler error)
FAIL: gcc.c-torture/execute/20050124-1.c -O2 -flto -fno-use-linker-plugin -flt
o-partition=none (test for excess errors)
....
Sorry for that.
That is caused not by this patch but rather by the followup
https://gcc.gnu.org/ml/gcc-patches/2015-11/msg03327.html
The checking assert fails:
gcc_checking_assert (!emit_a || !modified_in_p (orig_b, emit_a));
emit_a is:
(parallel [
(set (reg:SI 93)
(plus:SI (reg/v:SI 88 [ i ])
(const_int 2 [0x2])))
(clobber (reg:CC 17 flags))
])
and and orig_b is:
(if_then_else:SI (eq (reg:CC 17 flags)
(const_int 0 [0]))
(reg/v:SI 87 [ <retval> ])
(reg/v:SI 88 [ i ]))
So I think our assumption that this case would never trigger by this point
doesn't hold
due to the CC reg clobber.
So the code before that patch was probably correct.
I think we should revert
https://gcc.gnu.org/ml/gcc-patches/2015-11/msg03327.html then.
Kyrill
/space/rguenther/src/svn/trunk2/gcc/testsuite/gcc.c-torture/execute/20050124-1.c:19:1:
internal compiler error: in noce_try_cmove_arith, at ifcvt.c:2180^M
0x11f919d noce_try_cmove_arith^M
/space/rguenther/src/svn/trunk2/gcc/ifcvt.c:2180^M
0x11fb93f noce_process_if_block^M
/space/rguenther/src/svn/trunk2/gcc/ifcvt.c:3525^M
0x11fdd0e noce_find_if_block^M
/space/rguenther/src/svn/trunk2/gcc/ifcvt.c:3974^M
0x11fdd0e find_if_header^M
/space/rguenther/src/svn/trunk2/gcc/ifcvt.c:4179^M
0x11fdd0e if_convert^M
/space/rguenther/src/svn/trunk2/gcc/ifcvt.c:5326^M
0x11ff32d execute^M
on x86_64 with -m64 and -m32.
Richard.
Thanks,
Kyrill
2015-11-26 Kyrylo Tkachov <kyrylo.tkac...@arm.com>
PR rtl-optimization/68506
* ifcvt.c (noce_try_cmove_arith): Try emitting the else basic block
first if emit_a exists or then_bb modifies 'b'. Reindent if-else
blocks.
2015-11-26 Kyrylo Tkachov <kyrylo.tkac...@arm.com>
PR rtl-optimization/68506
* gcc.c-torture/execute/pr68506.c: New test.
Thanks for your guidance,
Kyrill
So take these deletions out and leave them for the followup, and the
patch is ok everywhere. No need for a full retest given that practically the
same patch has been tested already, just make sure you can build cc1.
Bernd
