diff --git a/llvm/test/Transforms/GVN/pr63019.ll b/llvm/test/Transforms/GVN/pr63019.ll new file mode 100644 index 0000000000000..cf3a4666a06e9 --- /dev/null +++ b/llvm/test/Transforms/GVN/pr63019.ll @@ -0,0 +1,42 @@ +; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 2 +; RUN: opt -S -passes=gvn < %s | FileCheck %s + +; FIXME: This is a miscompile. +define i8 @test(i1 %c, i64 %offset, ptr %ptr) { +; CHECK-LABEL: define i8 @test +; CHECK-SAME: (i1 [[C:%.*]], i64 [[OFFSET:%.*]], ptr [[PTR:%.*]]) { +; CHECK-NEXT: start: +; CHECK-NEXT: [[ALLOCA:%.*]] = alloca [8 x i8], align 8 +; CHECK-NEXT: store i64 1234605616436508552, ptr [[ALLOCA]], align 8 +; CHECK-NEXT: [[GEP_2:%.*]] = getelementptr i8, ptr [[ALLOCA]], i64 2 +; CHECK-NEXT: [[GEP_UNKNOWN:%.*]] = getelementptr i8, ptr [[ALLOCA]], i64 [[OFFSET]] +; CHECK-NEXT: br i1 [[C]], label [[JOIN:%.*]], label [[IF:%.*]] +; CHECK: if: +; CHECK-NEXT: br label [[JOIN]] +; CHECK: join: +; CHECK-NEXT: [[PHI:%.*]] = phi ptr [ [[GEP_UNKNOWN]], [[START:%.*]] ], [ [[GEP_2]], [[IF]] ] +; CHECK-NEXT: store i8 0, ptr [[ALLOCA]], align 8 +; CHECK-NEXT: [[LOAD1:%.*]] = load i64, ptr [[ALLOCA]], align 8 +; CHECK-NEXT: store i64 [[LOAD1]], ptr [[PTR]], align 8 +; CHECK-NEXT: [[TMP0:%.*]] = lshr i64 [[LOAD1]], 16 +; CHECK-NEXT: [[TMP1:%.*]] = trunc i64 [[TMP0]] to i8 +; CHECK-NEXT: ret i8 [[TMP1]] +; +start: + %alloca = alloca [8 x i8], align 8 + store i64 u0x1122334455667788, ptr %alloca, align 8 + %gep.2 = getelementptr i8, ptr %alloca, i64 2 + %gep.unknown = getelementptr i8, ptr %alloca, i64 %offset + br i1 %c, label %join, label %if + +if: + br label %join + +join: + %phi = phi ptr [ %gep.unknown, %start ], [ %gep.2, %if ] + store i8 0, ptr %alloca, align 8 + %load1 = load i64, ptr %alloca, align 8 + store i64 %load1, ptr %ptr, align 8 + %load2 = load i8, ptr %phi, align 1 + ret i8 %load2 +}