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| author | Craig Topper <craig.topper@intel.com> | 2017-06-22 16:23:30 +0000 |
|---|---|---|
| committer | Craig Topper <craig.topper@intel.com> | 2017-06-22 16:23:30 +0000 |
| commit | dffbbcb3fd42124842a8ae2cae18d40874d81f0b (patch) | |
| tree | c93a55597568ce81a9a497d1af6afd5f44068471 /llvm/test | |
| parent | a690e3cea23b17715fdbcecb24ae634ebc103fa5 (diff) | |
| download | bcm5719-llvm-dffbbcb3fd42124842a8ae2cae18d40874d81f0b.tar.gz bcm5719-llvm-dffbbcb3fd42124842a8ae2cae18d40874d81f0b.zip | |
[InstCombine] Teach foldSelectICmpAndOr to recognize (select (icmp slt (trunc (X)), 0), Y, (or Y, C2))
Summary:
InstCombine likes to turn (icmp eq (and X, C1), 0) into (icmp slt (trunc (X)), 0) sometimes. This breaks foldSelectICmpAndOr's ability to recognize (select (icmp eq (and X, C1), 0), Y, (or Y, C2))->(or (shl (and X, C1), C3), y).
This patch tries to recover this. I had to flip around some of the early out checks so that I could create a new And instruction during the compare processing without it possibly never getting used.
Reviewers: spatel, majnemer, davide
Reviewed By: spatel
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D34184
llvm-svn: 306029
Diffstat (limited to 'llvm/test')
| -rw-r--r-- | llvm/test/Transforms/InstCombine/select-with-bitwise-ops.ll | 19 |
1 files changed, 9 insertions, 10 deletions
diff --git a/llvm/test/Transforms/InstCombine/select-with-bitwise-ops.ll b/llvm/test/Transforms/InstCombine/select-with-bitwise-ops.ll index 7a1fc1be478..caec9412a7f 100644 --- a/llvm/test/Transforms/InstCombine/select-with-bitwise-ops.ll +++ b/llvm/test/Transforms/InstCombine/select-with-bitwise-ops.ll @@ -297,11 +297,10 @@ define i32 @test67(i16 %x) { define i32 @test68(i32 %x, i32 %y) { ; CHECK-LABEL: @test68( -; CHECK-NEXT: [[TMP1:%.*]] = trunc i32 [[X:%.*]] to i8 -; CHECK-NEXT: [[CMP:%.*]] = icmp sgt i8 [[TMP1]], -1 -; CHECK-NEXT: [[OR:%.*]] = or i32 [[Y:%.*]], 2 -; CHECK-NEXT: [[SELECT:%.*]] = select i1 [[CMP]], i32 [[Y]], i32 [[OR]] -; CHECK-NEXT: ret i32 [[SELECT]] +; CHECK-NEXT: [[TMP1:%.*]] = lshr i32 [[X:%.*]], 6 +; CHECK-NEXT: [[TMP2:%.*]] = and i32 [[TMP1]], 2 +; CHECK-NEXT: [[TMP3:%.*]] = or i32 [[TMP2]], [[Y:%.*]] +; CHECK-NEXT: ret i32 [[TMP3]] ; %and = and i32 %x, 128 %cmp = icmp eq i32 %and, 0 @@ -312,11 +311,11 @@ define i32 @test68(i32 %x, i32 %y) { define i32 @test69(i32 %x, i32 %y) { ; CHECK-LABEL: @test69( -; CHECK-NEXT: [[TMP1:%.*]] = trunc i32 [[X:%.*]] to i8 -; CHECK-NEXT: [[CMP:%.*]] = icmp slt i8 [[TMP1]], 0 -; CHECK-NEXT: [[OR:%.*]] = or i32 [[Y:%.*]], 2 -; CHECK-NEXT: [[SELECT:%.*]] = select i1 [[CMP]], i32 [[Y]], i32 [[OR]] -; CHECK-NEXT: ret i32 [[SELECT]] +; CHECK-NEXT: [[TMP1:%.*]] = lshr i32 [[X:%.*]], 6 +; CHECK-NEXT: [[TMP2:%.*]] = and i32 [[TMP1]], 2 +; CHECK-NEXT: [[TMP3:%.*]] = xor i32 [[TMP2]], 2 +; CHECK-NEXT: [[TMP4:%.*]] = or i32 [[TMP3]], [[Y:%.*]] +; CHECK-NEXT: ret i32 [[TMP4]] ; %and = and i32 %x, 128 %cmp = icmp ne i32 %and, 0 |
