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| author | Noah Goldstein <goldstein.w.n@gmail.com> | 2023-11-18 15:49:29 -0600 |
|---|---|---|
| committer | Noah Goldstein <goldstein.w.n@gmail.com> | 2023-11-19 12:15:03 -0600 |
| commit | f112e4693a9718ef55019ab4d68ede739b2dca3d (patch) | |
| tree | 8d5f5c8460241f4b881ec865f687201af90a2408 /llvm/test/Analysis | |
| parent | 3af514e5aea2a3e7774c667232ccd0d611cf911a (diff) | |
| download | llvm-f112e4693a9718ef55019ab4d68ede739b2dca3d.zip llvm-f112e4693a9718ef55019ab4d68ede739b2dca3d.tar.gz llvm-f112e4693a9718ef55019ab4d68ede739b2dca3d.tar.bz2 | |
[InstCombine] Don't transform `sub X, ~Y` -> `add X, -Y` unless `Y` is actually negatable
This combine was previously adding instruction in some cases (see the
tests).
Closes #72767
Diffstat (limited to 'llvm/test/Analysis')
| -rw-r--r-- | llvm/test/Analysis/ValueTracking/knownbits-and-or-xor-lowbit.ll | 5 |
1 files changed, 2 insertions, 3 deletions
diff --git a/llvm/test/Analysis/ValueTracking/knownbits-and-or-xor-lowbit.ll b/llvm/test/Analysis/ValueTracking/knownbits-and-or-xor-lowbit.ll index 7fbc780..f44948e 100644 --- a/llvm/test/Analysis/ValueTracking/knownbits-and-or-xor-lowbit.ll +++ b/llvm/test/Analysis/ValueTracking/knownbits-and-or-xor-lowbit.ll @@ -106,9 +106,8 @@ define <2 x i1> @sub_XY_and_bit0_is_zero_fail(<2 x i8> %x, <2 x i8> %C) nounwind define i1 @sub_XY_xor_bit0_is_one_fail(i8 %x, i8 %C) nounwind { ; CHECK-LABEL: @sub_XY_xor_bit0_is_one_fail( -; CHECK-NEXT: [[TMP1:%.*]] = xor i8 [[C:%.*]], -2 -; CHECK-NEXT: [[C1_NEG:%.*]] = add i8 [[TMP1]], 1 -; CHECK-NEXT: [[Y:%.*]] = add i8 [[C1_NEG]], [[X:%.*]] +; CHECK-NEXT: [[C1:%.*]] = xor i8 [[C:%.*]], 1 +; CHECK-NEXT: [[Y:%.*]] = sub i8 [[X:%.*]], [[C1]] ; CHECK-NEXT: [[W:%.*]] = xor i8 [[Y]], [[X]] ; CHECK-NEXT: [[R:%.*]] = icmp eq i8 [[W]], 10 ; CHECK-NEXT: ret i1 [[R]] |