| commit | 8d6b13da61aabc7c55d858ee3fd7ae22798d6a61 | |
| author | Richard Sandiford <richard.sandiford@arm.com> | |
| Fri, 5 Apr 2019 07:31:12 +0000 (5 07:31 +0000) | ||
| committer | Richard Sandiford <rsandifo@gcc.gnu.org> | |
| Fri, 5 Apr 2019 07:31:12 +0000 (5 07:31 +0000) | ||
| tree | 86736c1fa49087e473dfafc0789158746bd70baa | treesnapshot (tar.gz zip) |
| parent | ce36ba09fe2c1b8523265e217f8cb478f50607c3 | commitdiff |
Make FMA code cope with redundant negates (PR89956)
This patch fixes a case in which, due to forced missed optimisations
in earlier passes, we have:
_1 = a * b
_2 = -_1
_3 = -_1
_4 = _2 + _3
and treated _4 as two FNMA candidates, once via _2 and once via _3.
2019-04-05 Richard Sandiford <richard.sandiford@arm.com>
gcc/
PR tree-optimization/89956
* tree-ssa-math-opts.c (convert_mult_to_fma): Protect against
multiple negates of the same value.
gcc/testsuite/
PR tree-optimization/89956
* gfortran.dg/pr89956.f90: New test.
From-SVN: r270162
This patch fixes a case in which, due to forced missed optimisations
in earlier passes, we have:
_1 = a * b
_2 = -_1
_3 = -_1
_4 = _2 + _3
and treated _4 as two FNMA candidates, once via _2 and once via _3.
2019-04-05 Richard Sandiford <richard.sandiford@arm.com>
gcc/
PR tree-optimization/89956
* tree-ssa-math-opts.c (convert_mult_to_fma): Protect against
multiple negates of the same value.
gcc/testsuite/
PR tree-optimization/89956
* gfortran.dg/pr89956.f90: New test.
From-SVN: r270162
| gcc/ChangeLog | diffblobblamehistory | |
| gcc/testsuite/ChangeLog | diffblobblamehistory | |
| gcc/testsuite/gfortran.dg/pr89956.f90 | [new file with mode: 0644] | blob |
| gcc/tree-ssa-math-opts.c | diffblobblamehistory |