diff options
| -rw-r--r-- | llvm/lib/Analysis/ValueTracking.cpp | 38 | ||||
| -rw-r--r-- | llvm/test/Transforms/LICM/hoist-deref-load.ll | 82 |
2 files changed, 10 insertions, 110 deletions
diff --git a/llvm/lib/Analysis/ValueTracking.cpp b/llvm/lib/Analysis/ValueTracking.cpp index 65c5d0e9f9c..edd46c5fe36 100644 --- a/llvm/lib/Analysis/ValueTracking.cpp +++ b/llvm/lib/Analysis/ValueTracking.cpp @@ -1861,36 +1861,18 @@ static bool isKnownNonNullFromDominatingCondition(const Value *V, continue; for (auto *CmpU : U->users()) { - SmallVector<const User *, 4> WorkList; - SmallPtrSet<const User *, 4> Visited; - Visited.insert(CmpU); - WorkList.push_back(CmpU); - - while (!WorkList.empty()) { - auto *Curr = WorkList.pop_back_val(); - - // If a user is an AND, add all its users to the work list. - if (auto *BO = dyn_cast<BinaryOperator>(Curr)) - if (BO->getOpcode() == Instruction::And) { - for (auto *BOU : BO->users()) - if (Visited.insert(BOU).second) - WorkList.push_back(BOU); - continue; - } - - if (const BranchInst *BI = dyn_cast<BranchInst>(Curr)) { - assert(BI->isConditional() && "uses a comparison!"); + if (const BranchInst *BI = dyn_cast<BranchInst>(CmpU)) { + assert(BI->isConditional() && "uses a comparison!"); - BasicBlock *NonNullSuccessor = - BI->getSuccessor(Pred == ICmpInst::ICMP_EQ ? 1 : 0); - BasicBlockEdge Edge(BI->getParent(), NonNullSuccessor); - if (Edge.isSingleEdge() && DT->dominates(Edge, CtxI->getParent())) - return true; - } else if (Pred == ICmpInst::ICMP_NE && - match(Curr, m_Intrinsic<Intrinsic::experimental_guard>()) && - DT->dominates(cast<Instruction>(Curr), CtxI)) { + BasicBlock *NonNullSuccessor = + BI->getSuccessor(Pred == ICmpInst::ICMP_EQ ? 1 : 0); + BasicBlockEdge Edge(BI->getParent(), NonNullSuccessor); + if (Edge.isSingleEdge() && DT->dominates(Edge, CtxI->getParent())) return true; - } + } else if (Pred == ICmpInst::ICMP_NE && + match(CmpU, m_Intrinsic<Intrinsic::experimental_guard>()) && + DT->dominates(cast<Instruction>(CmpU), CtxI)) { + return true; } } } diff --git a/llvm/test/Transforms/LICM/hoist-deref-load.ll b/llvm/test/Transforms/LICM/hoist-deref-load.ll index bdc5aeaa2e7..b48c9e5c7b1 100644 --- a/llvm/test/Transforms/LICM/hoist-deref-load.ll +++ b/llvm/test/Transforms/LICM/hoist-deref-load.ll @@ -556,87 +556,5 @@ for.end: ; preds = %for.inc, %entry, %e ret void } -; Check that branch by condition "null check AND something" allows to hoist the -; load. -define void @test14(i32* noalias %a, i32* %b, i32* dereferenceable_or_null(4) %c, i32 %n, i1 %dummy_cond) #0 { - -; CHECK-LABEL: @test14 -; CHECK: load i32, i32* %c, align 4 -; CHECK: for.body: - -entry: - %not_null = icmp ne i32* %c, null - %dummy_and = and i1 %not_null, %dummy_cond - br i1 %dummy_and, label %not.null, label %for.end - -not.null: - %cmp11 = icmp sgt i32 %n, 0 - br i1 %cmp11, label %for.body, label %for.end - -for.body: ; preds = %not.null, %for.inc - %indvars.iv = phi i64 [ %indvars.iv.next, %for.inc ], [ 0, %not.null ] - %arrayidx = getelementptr inbounds i32, i32* %a, i64 %indvars.iv - %0 = load i32, i32* %arrayidx, align 4 - %cmp1 = icmp sgt i32 %0, 0 - br i1 %cmp1, label %if.then, label %for.inc - -if.then: ; preds = %for.body - %1 = load i32, i32* %c, align 4 - %arrayidx3 = getelementptr inbounds i32, i32* %b, i64 %indvars.iv - %2 = load i32, i32* %arrayidx3, align 4 - %mul = mul nsw i32 %2, %1 - store i32 %mul, i32* %arrayidx, align 4 - br label %for.inc - -for.inc: ; preds = %for.body, %if.then - %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1 - %lftr.wideiv = trunc i64 %indvars.iv.next to i32 - %exitcond = icmp eq i32 %lftr.wideiv, %n - br i1 %exitcond, label %for.end, label %for.body - -for.end: ; preds = %for.inc, %entry, %not.null - ret void -} - -; Check that guard by condition "null check AND something" allows to hoist the -; load. -define void @test15(i32* noalias %a, i32* %b, i32* dereferenceable_or_null(4) %c, i32 %n, i1 %dummy_cond) #0 { - -; CHECK-LABEL: @test15 -; CHECK: load i32, i32* %c, align 4 -; CHECK: for.body: - -entry: - %not_null = icmp ne i32* %c, null - %dummy_and = and i1 %not_null, %dummy_cond - call void(i1, ...) @llvm.experimental.guard(i1 %dummy_and) [ "deopt"() ] - %cmp11 = icmp sgt i32 %n, 0 - br i1 %cmp11, label %for.body, label %for.end - -for.body: ; preds = %entry, %for.inc - %indvars.iv = phi i64 [ %indvars.iv.next, %for.inc ], [ 0, %entry ] - %arrayidx = getelementptr inbounds i32, i32* %a, i64 %indvars.iv - %0 = load i32, i32* %arrayidx, align 4 - %cmp1 = icmp sgt i32 %0, 0 - br i1 %cmp1, label %if.then, label %for.inc - -if.then: ; preds = %for.body - %1 = load i32, i32* %c, align 4 - %arrayidx3 = getelementptr inbounds i32, i32* %b, i64 %indvars.iv - %2 = load i32, i32* %arrayidx3, align 4 - %mul = mul nsw i32 %2, %1 - store i32 %mul, i32* %arrayidx, align 4 - br label %for.inc - -for.inc: ; preds = %for.body, %if.then - %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1 - %lftr.wideiv = trunc i64 %indvars.iv.next to i32 - %exitcond = icmp eq i32 %lftr.wideiv, %n - br i1 %exitcond, label %for.end, label %for.body - -for.end: ; preds = %for.inc, %entry - ret void -} - attributes #0 = { nounwind uwtable } !0 = !{i64 4} |
