diff options
| -rw-r--r-- | llvm/lib/Transforms/Utils/SimplifyCFG.cpp | 4 | ||||
| -rw-r--r-- | llvm/test/Transforms/SimplifyCFG/sink-common-code.ll | 25 |
2 files changed, 28 insertions, 1 deletions
diff --git a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp b/llvm/lib/Transforms/Utils/SimplifyCFG.cpp index 6fe00a71ea1..6252169b83a 100644 --- a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp +++ b/llvm/lib/Transforms/Utils/SimplifyCFG.cpp @@ -1403,7 +1403,9 @@ static bool canSinkInstructions( auto *PNUse = dyn_cast<PHINode>(*I0->user_begin()); if (!all_of(Insts, [&PNUse](const Instruction *I) -> bool { auto *U = cast<Instruction>(*I->user_begin()); - return U == PNUse || U->getParent() == I->getParent(); + return (PNUse && + PNUse->getIncomingValueForBlock(I->getParent()) == I) || + U->getParent() == I->getParent(); })) return false; } diff --git a/llvm/test/Transforms/SimplifyCFG/sink-common-code.ll b/llvm/test/Transforms/SimplifyCFG/sink-common-code.ll index 66dfeb8658d..57533fa1408 100644 --- a/llvm/test/Transforms/SimplifyCFG/sink-common-code.ll +++ b/llvm/test/Transforms/SimplifyCFG/sink-common-code.ll @@ -585,6 +585,31 @@ if.end: ; CHECK: store ; CHECK: store +; The phi is confusing - both add instructions are used by it, but +; not on their respective unconditional arcs. It should not be +; optimized. +define void @test_pr30292(i1 %cond, i1 %cond2, i32 %a, i32 %b) { +entry: + %add1 = add i32 %a, 1 + br label %succ + +one: + br i1 %cond, label %two, label %succ + +two: + call void @g() + %add2 = add i32 %a, 1 + br label %succ + +succ: + %p = phi i32 [ 0, %entry ], [ %add1, %one ], [ %add2, %two ] + br label %one +} +declare void @g() + +; CHECK-LABEL: test_pr30292 +; CHECK: phi i32 [ 0, %entry ], [ %add1, %succ ], [ %add2, %two ] + ; CHECK: !0 = !{!1, !1, i64 0} ; CHECK: !1 = !{!"float", !2} ; CHECK: !2 = !{!"an example type tree"} |
