------- Comment #29 from dave at hiauly1 dot hia dot nrc dot ca 2010-07-18
21:15 -------
Subject: Re: [4.6 regression] Revision 162270 failed to bootstrap
> David, this seems to be caused by a different revision. The postreload pass
> we're discussing here makes no changes to RTL on that testcase. Please ensure
> you find the right revision that introduces a problem.
Possibly, that is true. The title of this PR was quite general. Anyway,
I will start a new PR if there are multiple unrelated issues. I will
determine the exact revision. Last successful bootstrap on this target
was 162195.
> -(insn 3 5 4 2 950605-1.c:3 (set (reg/v:DI 68 [ c+-7 ])
> - (zero_extend:DI (reg:SI 26 %r26 [ c+-3 ]))) 133 {*pa.md:4633} (nil))
> +(note 5 0 4 2 [bb 2] NOTE_INSN_BASIC_BLOCK)
It looks to me like the extend insn is wrong. With 4.4, we had
(insn 4 3 5 2
/test/gnu/gcc/gcc/gcc/testsuite/gcc.c-torture/execute/950605-1.c:3
(set (reg/v:DI 68 [ c+-7 ])
(zero_extend:DI (subreg:QI (reg:SI 69) 3))) -1 (nil))
> I can't find anything wrong with this, as it's a SImode comparison. Is the
> backend emitting the correct compare instruction?
The backend has only SImode and DImode comparisons.
Dave
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44970
