Optimize x < 0 ? ~y : y to (x >> 31) ^ y in match.pd
This copies the optimization that is done in phiopt for
"x < 0 ? ~y : y to (x >> 31) ^ y" into match.pd. The code
for phiopt is kept around until phiopt uses match.pd (which
I am working towards).
Note the original testcase is now optimized early on and I added a
new testcase to optimize during phiopt.
OK? Bootstrapped and tested on x86_64-linux-gnu with no regressions.
Thanks,
Andrew Pinski
Differences from v1:
V2: Add check for integeral type to make sure vector types are not done.
gcc:
* match.pd (x < 0 ? ~y : y): New patterns.
gcc/testsuite:
* gcc.dg/tree-ssa/pr96928.c: Update test for slightly different IR.
* gcc.dg/tree-ssa/pr96928-1.c: New testcase.