Commit Graph

5 Commits

Author SHA1 Message Date
Sanjay Patel
821bba7fda avoid infinite looping when folding vector multiplies of constants (PR22698)
We were missing a check for the following fold in DAGCombiner:

// fold (fmul (fmul x, c1), c2) -> (fmul x, (fmul c1, c2))

If 'x' is also a constant, then we shouldn't do anything. Otherwise, we could end up swapping the operands back and forth forever.

This should fix:
http://llvm.org/bugs/show_bug.cgi?id=22698

Differential Revision: http://reviews.llvm.org/D7917



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230884 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-01 00:09:35 +00:00
Sanjay Patel
558cd3c6a2 Add triple and remove hashes to account for buildbot differences in comment strings.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217601 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-11 16:08:44 +00:00
Sanjay Patel
04bb0e721f Combine fmul vector FP constants when unsafe math is allowed.
This is an extension of the change made with r215820:
http://llvm.org/viewvc/llvm-project?view=revision&revision=215820

That patch allowed combining of splatted vector FP constants that are multiplied.

This patch allows combining non-uniform vector FP constants too by relaxing the
check on the type of vector. Also, canonicalize a vector fmul in the
same way that we already do for scalars - if only one operand of the fmul is a
constant, make it operand 1. Otherwise, we miss potential folds.

This fold is also done by -instcombine, but it's possible that extra
fmuls may have been generated during lowering.

Differential Revision: http://reviews.llvm.org/D5254



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217599 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-11 15:45:27 +00:00
NAKAMURA Takumi
0ac5626b56 llvm/test/CodeGen/X86/fmul-combines.ll: Appease Windows x64. <4 x float> is passed by stack.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215821 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-16 22:28:37 +00:00
Matt Arsenault
5f8a9ae17c Fix fmul combines with constant splat vectors
Fixes things like fmul x, 2 -> fadd x, x

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215820 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-16 10:14:19 +00:00