Commit Graph

3 Commits

Author SHA1 Message Date
Eric Christopher cee313d288 Revert "Temporarily Revert "Add basic loop fusion pass.""
The reversion apparently deleted the test/Transforms directory.

Will be re-reverting again.

llvm-svn: 358552
2019-04-17 04:52:47 +00:00
Eric Christopher a863435128 Temporarily Revert "Add basic loop fusion pass."
As it's causing some bot failures (and per request from kbarton).

This reverts commit r358543/ab70da07286e618016e78247e4a24fcb84077fda.

llvm-svn: 358546
2019-04-17 02:12:23 +00:00
Daniel Neilson 901acfab0c [InstCombine] Fold compare of int constant against a splatted vector of ints
Summary:
Folding patterns like:
  %vec = shufflevector <4 x i8> %insvec, <4 x i8> undef, <4 x i32> zeroinitializer
  %cast = bitcast <4 x i8> %vec to i32
  %cond = icmp eq i32 %cast, 0
into:
  %ext = extractelement <4 x i8> %insvec, i32 0
  %cond = icmp eq i32 %ext, 0

Combined with existing rules, this allows us to fold patterns like:
  %insvec = insertelement <4 x i8> undef, i8 %val, i32 0
  %vec = shufflevector <4 x i8> %insvec, <4 x i8> undef, <4 x i32> zeroinitializer
  %cast = bitcast <4 x i8> %vec to i32
  %cond = icmp eq i32 %cast, 0
into:
  %cond = icmp eq i8 %val, 0

When we construct a splat vector via a shuffle, and bitcast the vector into an integer type for comparison against an integer constant. Then we can simplify the the comparison to compare the splatted value against the integer constant.

Reviewers: spatel, anna, mkazantsev

Reviewed By: spatel

Subscribers: efriedma, rengolin, llvm-commits

Differential Revision: https://reviews.llvm.org/D44997

llvm-svn: 329087
2018-04-03 17:26:20 +00:00