diff options
| -rw-r--r-- | llvm/lib/Analysis/ValueTracking.cpp | 4 | ||||
| -rw-r--r-- | llvm/test/Transforms/InstCombine/assume.ll | 18 |
2 files changed, 19 insertions, 3 deletions
diff --git a/llvm/lib/Analysis/ValueTracking.cpp b/llvm/lib/Analysis/ValueTracking.cpp index b4473f857e2..64250f6360e 100644 --- a/llvm/lib/Analysis/ValueTracking.cpp +++ b/llvm/lib/Analysis/ValueTracking.cpp @@ -617,9 +617,7 @@ static void computeKnownBitsFromAssume(const Value *V, KnownBits &Known, continue; Value *A, *B; - auto m_V = m_CombineOr(m_Specific(V), - m_CombineOr(m_PtrToInt(m_Specific(V)), - m_BitCast(m_Specific(V)))); + auto m_V = m_CombineOr(m_Specific(V), m_PtrToInt(m_Specific(V))); CmpInst::Predicate Pred; uint64_t C; diff --git a/llvm/test/Transforms/InstCombine/assume.ll b/llvm/test/Transforms/InstCombine/assume.ll index f861741db26..ec345b253fb 100644 --- a/llvm/test/Transforms/InstCombine/assume.ll +++ b/llvm/test/Transforms/InstCombine/assume.ll @@ -320,6 +320,24 @@ define void @debug_interference(i8 %x) { ret void } +; This would crash. +; Does it ever make sense to peek through a bitcast of the icmp operand? + +define i32 @PR40940(<4 x i8> %x) { +; CHECK-LABEL: @PR40940( +; CHECK-NEXT: [[SHUF:%.*]] = shufflevector <4 x i8> [[X:%.*]], <4 x i8> undef, <4 x i32> <i32 1, i32 1, i32 2, i32 3> +; CHECK-NEXT: [[T2:%.*]] = bitcast <4 x i8> [[SHUF]] to i32 +; CHECK-NEXT: [[T3:%.*]] = icmp ult i32 [[T2]], 65536 +; CHECK-NEXT: call void @llvm.assume(i1 [[T3]]) +; CHECK-NEXT: ret i32 [[T2]] +; + %shuf = shufflevector <4 x i8> %x, <4 x i8> undef, <4 x i32> <i32 1, i32 1, i32 2, i32 3> + %t2 = bitcast <4 x i8> %shuf to i32 + %t3 = icmp ult i32 %t2, 65536 + call void @llvm.assume(i1 %t3) + ret i32 %t2 +} + declare void @llvm.dbg.value(metadata, metadata, metadata) !llvm.dbg.cu = !{!0} |
