Author: Nikita Popov Date: 2025-02-11T14:15:45-08:00 New Revision: a89e04e7f0caa28d607e38099b905063b47a88fb
URL: https://github.com/llvm/llvm-project/commit/a89e04e7f0caa28d607e38099b905063b47a88fb DIFF: https://github.com/llvm/llvm-project/commit/a89e04e7f0caa28d607e38099b905063b47a88fb.diff LOG: [ValueTracking] Add additional tests for computeKnownBits on GEPs (NFC) These demonstrate miscompiles in the existing code. (cherry picked from commit 3dc1ef1650c8389a6f195a474781cf2281208bed) Added: Modified: llvm/unittests/Analysis/ValueTrackingTest.cpp Removed: ################################################################################ diff --git a/llvm/unittests/Analysis/ValueTrackingTest.cpp b/llvm/unittests/Analysis/ValueTrackingTest.cpp index ee44aac45594d..39865fa195cf7 100644 --- a/llvm/unittests/Analysis/ValueTrackingTest.cpp +++ b/llvm/unittests/Analysis/ValueTrackingTest.cpp @@ -2679,6 +2679,41 @@ TEST_F(ComputeKnownBitsTest, ComputeKnownBitsAbsoluteSymbol) { EXPECT_EQ(0u, Known_0_256_Align8.countMinTrailingOnes()); } +TEST_F(ComputeKnownBitsTest, ComputeKnownBitsGEPExtendBeforeMul) { + // FIXME: The index should be extended before multiplying with the scale. + parseAssembly(R"( + target datalayout = "p:16:16:16" + + define void @test(i16 %arg) { + %and = and i16 %arg, u0x8000 + %base = inttoptr i16 %and to ptr + %A = getelementptr i32, ptr %base, i8 80 + ret void + } + )"); + KnownBits Known = computeKnownBits(A, M->getDataLayout()); + EXPECT_EQ(~64 & 0x7fff, Known.Zero); + EXPECT_EQ(64, Known.One); +} + +TEST_F(ComputeKnownBitsTest, ComputeKnownBitsGEPOnlyIndexBits) { + // FIXME: GEP should only affect the index width. + parseAssembly(R"( + target datalayout = "p:16:16:16:8" + + define void @test(i16 %arg) { + %and = and i16 %arg, u0x8000 + %or = or i16 %and, u0x00ff + %base = inttoptr i16 %or to ptr + %A = getelementptr i8, ptr %base, i8 1 + ret void + } + )"); + KnownBits Known = computeKnownBits(A, M->getDataLayout()); + EXPECT_EQ(0x7eff, Known.Zero); + EXPECT_EQ(0x100, Known.One); +} + TEST_F(ValueTrackingTest, HaveNoCommonBitsSet) { { // Check for an inverted mask: (X & ~M) op (Y & M). _______________________________________________ llvm-branch-commits mailing list llvm-branch-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-branch-commits
