[PR66726] Fixe regression caused by Factor conversion out of COND_EXPR

[Kugan <kugan dot vivekanandarajah at linaro dot org>]

Hi,

This is an updated version of
https://gcc.gnu.org/ml/gcc-patches/2015-07/msg02196.html.

Patch to fix PR66726 missed optimization, factor conversion out of
COND_EXPR caused a regression for targets with branch cost greater than
i.e., testcase gcc.dg/pr46309.c failed for these targets. I posted a
patch for this which had some issues. Please find an updated version of
this patch that now passes regression.

This patch makes optimize_range_tests understand the factored out
COND_EXPR. i.e., Updated the final_range_test_p to look for the new
pattern. Changed the maybe_optimize_range_tests (which does the inter
basic block range test optimization) accordingly.

Bootstrapped and regression tested on x86_64-none-linux-gnu with no new
regressions. And also regression tested on arm-none-linux-gnu and
aarch64-none-linux-gnu with no new regressions.
Is this Ok for trunk?

Thanks,
Kugan


gcc/ChangeLog:

2016-01-19  Kugan Vivekanandarajah  <kuganv@linaro.org>

	PR middle-end/66726
	* tree-ssa-reassoc.c (optimize_range_tests): Handle tcc_compare stmt
	whose result is used in PHI.
	(maybe_optimize_range_tests): Likewise.
	(final_range_test_p): Lokweise.

Attachment: p.txt
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