diff options
| -rw-r--r-- | llvm/lib/Analysis/ValueTracking.cpp | 4 | ||||
| -rw-r--r-- | llvm/test/Transforms/InstCombine/select-implied.ll | 36 |
2 files changed, 38 insertions, 2 deletions
diff --git a/llvm/lib/Analysis/ValueTracking.cpp b/llvm/lib/Analysis/ValueTracking.cpp index 514b8f29f84..5285fa5b98d 100644 --- a/llvm/lib/Analysis/ValueTracking.cpp +++ b/llvm/lib/Analysis/ValueTracking.cpp @@ -4405,8 +4405,8 @@ Optional<bool> llvm::isImpliedCondition(const Value *LHS, const Value *RHS, assert(OpTy->getScalarType()->isIntegerTy(1)); // LHS ==> RHS by definition - if (!LHSIsFalse && LHS == RHS) - return true; + if (LHS == RHS) + return !LHSIsFalse; if (OpTy->isVectorTy()) // TODO: extending the code below to handle vectors diff --git a/llvm/test/Transforms/InstCombine/select-implied.ll b/llvm/test/Transforms/InstCombine/select-implied.ll index 6b2ec7ffce7..2558745c18f 100644 --- a/llvm/test/Transforms/InstCombine/select-implied.ll +++ b/llvm/test/Transforms/InstCombine/select-implied.ll @@ -162,3 +162,39 @@ fpath: end: ret i32 0 } + +; LHS ==> RHS by definition (true -> true) +; CHECK-LABEL: @test6 +; CHECK: taken: +; CHECK-NOT: select +; CHECK: call void @foo(i32 10) +define void @test6(i32 %a, i32 %b) { + %cmp1 = icmp eq i32 %a, %b + br i1 %cmp1, label %taken, label %end + +taken: + %c = select i1 %cmp1, i32 10, i32 0 + call void @foo(i32 %c) + br label %end + +end: + ret void +} + +; LHS ==> RHS by definition (false -> false) +; CHECK-LABEL: @test7 +; CHECK: taken: +; CHECK-NOT: select +; CHECK: call void @foo(i32 11) +define void @test7(i32 %a, i32 %b) { + %cmp1 = icmp eq i32 %a, %b + br i1 %cmp1, label %end, label %taken + +taken: + %c = select i1 %cmp1, i32 0, i32 11 + call void @foo(i32 %c) + br label %end + +end: + ret void +} |
