On 07/09/15 20:14, H.J. Lu wrote:
On Mon, Sep 7, 2015 at 9:29 AM, Kyrill Tkachov <kyrylo.tkac...@arm.com> wrote:
Hi all,
This patch fixes the PRs in the ChangeLog that have been reported against my
if-conversion patch.
The problem occurs when the 'then' block is complex but the else block is
empty.
In this case the calling code in noce_process_if_block takes the 'else' move
(x := b) from
the test block. However, we have not checked whether the test block is valid
for complex-block
if-conversion with bb_valid_for_noce_process_p. Also, that's a case I wasn't
particularly targeting
when writing the initial patch.
This patch bails out of noce_try_cmove_arith when one of the blocks is
complex and the other is empty.
I've checked that if-conversion still happens in the cases of interest from
the original patch.
I've added the testcase from PR 67465 since that one uses __builtin_abort
and triggers the problem nicely.
The others show the miscompilation using printf seems to go away if I
replace it with an abort.
I have confirmed manually that the miscompilation goes away on those
testcases.
PR rtl-optimization/67481 is a testsuite regression on sparc-solaris that
Rainer reported. I haven't tested
that this patch fixes that, but I suspect that the root cause is the same.
Rainer, could you please
check that this fixes the regression for you?
Bootstrapped and tested on aarch64 and x86_64.
Ok for trunk if sparc testing comes ok?
Thanks,
Kyrill
2015-09-07 Kyrylo Tkachov <kyrylo.tkac...@arm.com>
PR rtl-optimization/67456
PR rtl-optimization/67464
PR rtl-optimization/67465
PR rtl-optimization/67481
* ifcvt.c (noce_try_cmove_arith): Bail out if one of the blocks
is complex and the other is empty.
2015-09-07 Kyrylo Tkachov <kyrylo.tkac...@arm.com>
* gcc.dg/pr67465.c: New test.
Does it fix
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67462
No, PR 67462 is a testism. I've added a comment to the issue with my thoughts.
Kyrill
