diff options
| author | Sanjay Patel <spatel@rotateright.com> | 2018-09-19 15:57:40 +0000 |
|---|---|---|
| committer | Sanjay Patel <spatel@rotateright.com> | 2018-09-19 15:57:40 +0000 |
| commit | 4fd2e2a4980d3a0512524b8352669ef4aa9258a9 (patch) | |
| tree | e8a4697b5a408a2abaaf3d996544de30bf18f4a0 /llvm/utils | |
| parent | bd810dbd276a8d8150862b0ede16ea200c89546d (diff) | |
| download | bcm5719-llvm-4fd2e2a4980d3a0512524b8352669ef4aa9258a9.tar.gz bcm5719-llvm-4fd2e2a4980d3a0512524b8352669ef4aa9258a9.zip | |
[DAGCombiner][x86] add transform/hook to decompose integer multiply into shift/add
This is an alternative to D37896. I don't see a way to decompose multiplies
generically without a target hook to tell us when it's profitable.
ARM and AArch64 may be able to remove some duplicate code that overlaps with
this transform.
As a first step, we're only getting the most clear wins on the vector examples
requested in PR34474:
https://bugs.llvm.org/show_bug.cgi?id=34474
As noted in the code comment, it's likely that the x86 constraints are tighter
than necessary, but it may not always be a win to replace a pmullw/pmulld.
Differential Revision: https://reviews.llvm.org/D52195
llvm-svn: 342554
Diffstat (limited to 'llvm/utils')
0 files changed, 0 insertions, 0 deletions
