[llvm] 0895b83 - [SimplifyCFG] FoldBranchToCommonDest(): don't deal with unconditional branches
Roman Lebedev via llvm-commits
llvm-commits at lists.llvm.org
Fri Jan 22 06:24:35 PST 2021
Author: Roman Lebedev
Date: 2021-01-22T17:22:49+03:00
New Revision: 0895b836d74ed333468ddece2102140494eb33b6
URL: https://github.com/llvm/llvm-project/commit/0895b836d74ed333468ddece2102140494eb33b6
DIFF: https://github.com/llvm/llvm-project/commit/0895b836d74ed333468ddece2102140494eb33b6.diff
LOG: [SimplifyCFG] FoldBranchToCommonDest(): don't deal with unconditional branches
The case where BB ends with an unconditional branch,
and has a single predecessor w/ conditional branch
to BB and a single successor of BB is exactly the pattern
SpeculativelyExecuteBB() transform deals with.
(and in this case they both allow speculating only a single instruction)
Well, or FoldTwoEntryPHINode(), if the final block
has only those two predecessors.
Here, in FoldBranchToCommonDest(), only a weird subset of that
transform is supported, and it's glued on the side in a weird way.
In particular, it took me a bit to understand that the Cond
isn't actually a branch condition in that case, but just the value
we allow to speculate (otherwise it reads as a miscompile to me).
Additionally, this only supports for the speculated instruction
to be an ICmp.
So let's just unclutter FoldBranchToCommonDest(), and leave
this transform up to SpeculativelyExecuteBB(). As far as i can tell,
this shouldn't really impact optimization potential, but if it does,
improving SpeculativelyExecuteBB() will be more beneficial anyways.
Notably, this only affects a single test,
but EarlyCSE should have run beforehand in the pipeline,
and then FoldTwoEntryPHINode() would have caught it.
This reverts commit rL158392 / commit d33f4efbfdef6ffccf212ab3e40a7673589085fd.
Added:
Modified:
llvm/lib/Transforms/Utils/SimplifyCFG.cpp
llvm/test/Transforms/SimplifyCFG/branch-fold.ll
Removed:
llvm/test/Transforms/SimplifyCFG/X86/fold-branch-debuginvariant.ll
################################################################################
diff --git a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp b/llvm/lib/Transforms/Utils/SimplifyCFG.cpp
index a243a2e37950..d0028c013fa3 100644
--- a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp
+++ b/llvm/lib/Transforms/Utils/SimplifyCFG.cpp
@@ -314,46 +314,6 @@ SafeToMergeTerminators(Instruction *SI1, Instruction *SI2,
return !Fail;
}
-/// Return true if it is safe and profitable to merge these two terminator
-/// instructions together, where SI1 is an unconditional branch. PhiNodes will
-/// store all PHI nodes in common successors.
-static bool
-isProfitableToFoldUnconditional(BranchInst *SI1, BranchInst *SI2,
- Instruction *Cond,
- SmallVectorImpl<PHINode *> &PhiNodes) {
- if (SI1 == SI2)
- return false; // Can't merge with self!
- assert(SI1->isUnconditional() && SI2->isConditional());
-
- // We fold the unconditional branch if we can easily update all PHI nodes in
- // common successors:
- // 1> We have a constant incoming value for the conditional branch;
- // 2> We have "Cond" as the incoming value for the unconditional branch;
- // 3> SI2->getCondition() and Cond have same operands.
- CmpInst *Ci2 = dyn_cast<CmpInst>(SI2->getCondition());
- if (!Ci2)
- return false;
- if (!(Cond->getOperand(0) == Ci2->getOperand(0) &&
- Cond->getOperand(1) == Ci2->getOperand(1)) &&
- !(Cond->getOperand(0) == Ci2->getOperand(1) &&
- Cond->getOperand(1) == Ci2->getOperand(0)))
- return false;
-
- BasicBlock *SI1BB = SI1->getParent();
- BasicBlock *SI2BB = SI2->getParent();
- SmallPtrSet<BasicBlock *, 16> SI1Succs(succ_begin(SI1BB), succ_end(SI1BB));
- for (BasicBlock *Succ : successors(SI2BB))
- if (SI1Succs.count(Succ))
- for (BasicBlock::iterator BBI = Succ->begin(); isa<PHINode>(BBI); ++BBI) {
- PHINode *PN = cast<PHINode>(BBI);
- if (PN->getIncomingValueForBlock(SI1BB) != Cond ||
- !isa<ConstantInt>(PN->getIncomingValueForBlock(SI2BB)))
- return false;
- PhiNodes.push_back(PN);
- }
- return true;
-}
-
/// Update PHI nodes in Succ to indicate that there will now be entries in it
/// from the 'NewPred' block. The values that will be flowing into the PHI nodes
/// will be the same as those coming in from ExistPred, an existing predecessor
@@ -2783,23 +2743,6 @@ bool SimplifyCFGOpt::SimplifyCondBranchToTwoReturns(BranchInst *BI,
return true;
}
-/// Return true if the given instruction is available
-/// in its predecessor block. If yes, the instruction will be removed.
-static bool tryCSEWithPredecessor(Instruction *Inst, BasicBlock *PB) {
- if (!isa<BinaryOperator>(Inst) && !isa<CmpInst>(Inst))
- return false;
- for (Instruction &I : *PB) {
- Instruction *PBI = &I;
- // Check whether Inst and PBI generate the same value.
- if (Inst->isIdenticalTo(PBI)) {
- Inst->replaceAllUsesWith(PBI);
- Inst->eraseFromParent();
- return true;
- }
- }
- return false;
-}
-
/// Return true if either PBI or BI has branch weight available, and store
/// the weights in {Pred|Succ}{True|False}Weight. If one of PBI and BI does
/// not have branch weight, use 1:1 as its weight.
@@ -2830,6 +2773,11 @@ bool llvm::FoldBranchToCommonDest(BranchInst *BI, DomTreeUpdater *DTU,
MemorySSAUpdater *MSSAU,
const TargetTransformInfo *TTI,
unsigned BonusInstThreshold) {
+ // If this block ends with an unconditional branch,
+ // let SpeculativelyExecuteBB() deal with it.
+ if (!BI->isConditional())
+ return false;
+
BasicBlock *BB = BI->getParent();
const unsigned PredCount = pred_size(BB);
@@ -2845,37 +2793,7 @@ bool llvm::FoldBranchToCommonDest(BranchInst *BI, DomTreeUpdater *DTU,
BB->getParent()->hasMinSize() ? TargetTransformInfo::TCK_CodeSize
: TargetTransformInfo::TCK_SizeAndLatency;
- Instruction *Cond = nullptr;
- if (BI->isConditional())
- Cond = dyn_cast<Instruction>(BI->getCondition());
- else {
- // For unconditional branch, check for a simple CFG pattern, where
- // BB has a single predecessor and BB's successor is also its predecessor's
- // successor. If such pattern exists, check for CSE between BB and its
- // predecessor.
- if (BasicBlock *PB = BB->getSinglePredecessor())
- if (BranchInst *PBI = dyn_cast<BranchInst>(PB->getTerminator()))
- if (PBI->isConditional() &&
- (BI->getSuccessor(0) == PBI->getSuccessor(0) ||
- BI->getSuccessor(0) == PBI->getSuccessor(1))) {
- for (auto I = BB->instructionsWithoutDebug().begin(),
- E = BB->instructionsWithoutDebug().end();
- I != E;) {
- Instruction *Curr = &*I++;
- if (isa<CmpInst>(Curr)) {
- Cond = Curr;
- break;
- }
- // Quit if we can't remove this instruction.
- if (!tryCSEWithPredecessor(Curr, PB))
- return Changed;
- Changed = true;
- }
- }
-
- if (!Cond)
- return Changed;
- }
+ Instruction *Cond = dyn_cast<Instruction>(BI->getCondition());
if (!Cond || (!isa<CmpInst>(Cond) && !isa<BinaryOperator>(Cond)) ||
Cond->getParent() != BB || !Cond->hasOneUse())
@@ -2934,7 +2852,7 @@ bool llvm::FoldBranchToCommonDest(BranchInst *BI, DomTreeUpdater *DTU,
// Finally, don't infinitely unroll conditional loops.
BasicBlock *TrueDest = BI->getSuccessor(0);
- BasicBlock *FalseDest = (BI->isConditional()) ? BI->getSuccessor(1) : nullptr;
+ BasicBlock *FalseDest = BI->getSuccessor(1);
if (TrueDest == BB || FalseDest == BB)
return Changed;
@@ -2945,39 +2863,30 @@ bool llvm::FoldBranchToCommonDest(BranchInst *BI, DomTreeUpdater *DTU,
// Check that we have two conditional branches. If there is a PHI node in
// the common successor, verify that the same value flows in from both
// blocks.
- SmallVector<PHINode *, 4> PHIs;
- if (!PBI || PBI->isUnconditional() ||
- (BI->isConditional() && !SafeToMergeTerminators(BI, PBI)) ||
- (!BI->isConditional() &&
- !isProfitableToFoldUnconditional(BI, PBI, Cond, PHIs)))
+ if (!PBI || PBI->isUnconditional() || !SafeToMergeTerminators(BI, PBI))
continue;
// Determine if the two branches share a common destination.
Instruction::BinaryOps Opc = Instruction::BinaryOpsEnd;
bool InvertPredCond = false;
- if (BI->isConditional()) {
- if (PBI->getSuccessor(0) == TrueDest) {
- Opc = Instruction::Or;
- } else if (PBI->getSuccessor(1) == FalseDest) {
- Opc = Instruction::And;
- } else if (PBI->getSuccessor(0) == FalseDest) {
- Opc = Instruction::And;
- InvertPredCond = true;
- } else if (PBI->getSuccessor(1) == TrueDest) {
- Opc = Instruction::Or;
- InvertPredCond = true;
- } else {
- continue;
- }
+ if (PBI->getSuccessor(0) == TrueDest) {
+ Opc = Instruction::Or;
+ } else if (PBI->getSuccessor(1) == FalseDest) {
+ Opc = Instruction::And;
+ } else if (PBI->getSuccessor(0) == FalseDest) {
+ Opc = Instruction::And;
+ InvertPredCond = true;
+ } else if (PBI->getSuccessor(1) == TrueDest) {
+ Opc = Instruction::Or;
+ InvertPredCond = true;
} else {
- if (PBI->getSuccessor(0) != TrueDest && PBI->getSuccessor(1) != TrueDest)
- continue;
+ continue;
}
// Check the cost of inserting the necessary logic before performing the
// transformation.
- if (TTI && Opc != Instruction::BinaryOpsEnd) {
+ if (TTI) {
Type *Ty = BI->getCondition()->getType();
unsigned Cost = TTI->getArithmeticInstrCost(Opc, Ty, CostKind);
if (InvertPredCond && (!PBI->getCondition()->hasOneUse() ||
@@ -2991,8 +2900,6 @@ bool llvm::FoldBranchToCommonDest(BranchInst *BI, DomTreeUpdater *DTU,
LLVM_DEBUG(dbgs() << "FOLDING BRANCH TO COMMON DEST:\n" << *PBI << *BB);
Changed = true;
- SmallVector<DominatorTree::UpdateType, 3> Updates;
-
IRBuilder<> Builder(PBI);
// The builder is used to create instructions to eliminate the branch in BB.
// If BB's terminator has !annotation metadata, add it to the new
@@ -3015,16 +2922,12 @@ bool llvm::FoldBranchToCommonDest(BranchInst *BI, DomTreeUpdater *DTU,
PBI->swapSuccessors();
}
- BasicBlock *UniqueSucc =
- BI->isConditional()
- ? (PBI->getSuccessor(0) == BB ? TrueDest : FalseDest)
- : TrueDest;
+ BasicBlock *UniqueSucc = PBI->getSuccessor(0) == BB ? TrueDest : FalseDest;
// Before cloning instructions, notify the successor basic block that it
// is about to have a new predecessor. This will update PHI nodes,
// which will allow us to update live-out uses of bonus instructions.
- if (BI->isConditional())
- AddPredecessorToBlock(UniqueSucc, PredBlock, BB, MSSAU);
+ AddPredecessorToBlock(UniqueSucc, PredBlock, BB, MSSAU);
// If we have bonus instructions, clone them into the predecessor block.
// Note that there may be multiple predecessor blocks, so we cannot move
@@ -3094,120 +2997,64 @@ bool llvm::FoldBranchToCommonDest(BranchInst *BI, DomTreeUpdater *DTU,
if (User->getParent() != UniqueSucc)
return false;
// Update the incoming value for the new predecessor.
- return PN->getIncomingBlock(U) ==
- (BI->isConditional() ? PredBlock : BB);
+ return PN->getIncomingBlock(U) == PredBlock;
});
}
// Now that the Cond was cloned into the predecessor basic block,
// or/and the two conditions together.
- if (BI->isConditional()) {
- Instruction *NewCond = cast<Instruction>(
- Builder.CreateBinOp(Opc, PBI->getCondition(), CondInPred, "or.cond"));
- PBI->setCondition(NewCond);
-
- uint64_t PredTrueWeight, PredFalseWeight, SuccTrueWeight, SuccFalseWeight;
- bool HasWeights =
- extractPredSuccWeights(PBI, BI, PredTrueWeight, PredFalseWeight,
- SuccTrueWeight, SuccFalseWeight);
- SmallVector<uint64_t, 8> NewWeights;
-
- if (PBI->getSuccessor(0) == BB) {
- if (HasWeights) {
- // PBI: br i1 %x, BB, FalseDest
- // BI: br i1 %y, UniqueSucc, FalseDest
- // TrueWeight is TrueWeight for PBI * TrueWeight for BI.
- NewWeights.push_back(PredTrueWeight * SuccTrueWeight);
- // FalseWeight is FalseWeight for PBI * TotalWeight for BI +
- // TrueWeight for PBI * FalseWeight for BI.
- // We assume that total weights of a BranchInst can fit into 32 bits.
- // Therefore, we will not have overflow using 64-bit arithmetic.
- NewWeights.push_back(PredFalseWeight *
- (SuccFalseWeight + SuccTrueWeight) +
- PredTrueWeight * SuccFalseWeight);
- }
- PBI->setSuccessor(0, UniqueSucc);
- }
- if (PBI->getSuccessor(1) == BB) {
- if (HasWeights) {
- // PBI: br i1 %x, TrueDest, BB
- // BI: br i1 %y, TrueDest, UniqueSucc
- // TrueWeight is TrueWeight for PBI * TotalWeight for BI +
- // FalseWeight for PBI * TrueWeight for BI.
- NewWeights.push_back(PredTrueWeight *
- (SuccFalseWeight + SuccTrueWeight) +
- PredFalseWeight * SuccTrueWeight);
- // FalseWeight is FalseWeight for PBI * FalseWeight for BI.
- NewWeights.push_back(PredFalseWeight * SuccFalseWeight);
- }
- PBI->setSuccessor(1, UniqueSucc);
- }
- if (NewWeights.size() == 2) {
- // Halve the weights if any of them cannot fit in an uint32_t
- FitWeights(NewWeights);
+ Instruction *NewCond = cast<Instruction>(
+ Builder.CreateBinOp(Opc, PBI->getCondition(), CondInPred, "or.cond"));
+ PBI->setCondition(NewCond);
- SmallVector<uint32_t, 8> MDWeights(NewWeights.begin(),
- NewWeights.end());
- setBranchWeights(PBI, MDWeights[0], MDWeights[1]);
- } else
- PBI->setMetadata(LLVMContext::MD_prof, nullptr);
+ uint64_t PredTrueWeight, PredFalseWeight, SuccTrueWeight, SuccFalseWeight;
+ bool HasWeights =
+ extractPredSuccWeights(PBI, BI, PredTrueWeight, PredFalseWeight,
+ SuccTrueWeight, SuccFalseWeight);
+ SmallVector<uint64_t, 8> NewWeights;
- Updates.push_back({DominatorTree::Insert, PredBlock, UniqueSucc});
- Updates.push_back({DominatorTree::Delete, PredBlock, BB});
- } else {
- // Update PHI nodes in the common successors.
- for (unsigned i = 0, e = PHIs.size(); i != e; ++i) {
- ConstantInt *PBI_C = cast<ConstantInt>(
- PHIs[i]->getIncomingValueForBlock(PBI->getParent()));
- assert(PBI_C->getType()->isIntegerTy(1));
- Instruction *MergedCond = nullptr;
- if (PBI->getSuccessor(0) == UniqueSucc) {
- Updates.push_back(
- {DominatorTree::Delete, PredBlock, PBI->getSuccessor(1)});
- // Create (PBI_Cond and PBI_C) or (!PBI_Cond and BI_Value)
- // PBI_C is true: PBI_Cond or (!PBI_Cond and BI_Value)
- // is false: !PBI_Cond and BI_Value
- Instruction *NotCond = cast<Instruction>(
- Builder.CreateNot(PBI->getCondition(), "not.cond"));
- MergedCond = cast<Instruction>(
- Builder.CreateBinOp(Instruction::And, NotCond, CondInPred,
- "and.cond"));
- if (PBI_C->isOne())
- MergedCond = cast<Instruction>(Builder.CreateBinOp(
- Instruction::Or, PBI->getCondition(), MergedCond, "or.cond"));
- } else {
- assert(PBI->getSuccessor(1) == UniqueSucc && "Unexpected branch");
- Updates.push_back(
- {DominatorTree::Delete, PredBlock, PBI->getSuccessor(0)});
- // Create (PBI_Cond and BI_Value) or (!PBI_Cond and PBI_C)
- // PBI_C is true: (PBI_Cond and BI_Value) or (!PBI_Cond)
- // is false: PBI_Cond and BI_Value
- MergedCond = cast<Instruction>(Builder.CreateBinOp(
- Instruction::And, PBI->getCondition(), CondInPred, "and.cond"));
- if (PBI_C->isOne()) {
- Instruction *NotCond = cast<Instruction>(
- Builder.CreateNot(PBI->getCondition(), "not.cond"));
- MergedCond = cast<Instruction>(Builder.CreateBinOp(
- Instruction::Or, NotCond, MergedCond, "or.cond"));
- }
- }
- // Update PHI Node.
- PHIs[i]->setIncomingValueForBlock(PBI->getParent(), MergedCond);
+ if (PBI->getSuccessor(0) == BB) {
+ if (HasWeights) {
+ // PBI: br i1 %x, BB, FalseDest
+ // BI: br i1 %y, UniqueSucc, FalseDest
+ // TrueWeight is TrueWeight for PBI * TrueWeight for BI.
+ NewWeights.push_back(PredTrueWeight * SuccTrueWeight);
+ // FalseWeight is FalseWeight for PBI * TotalWeight for BI +
+ // TrueWeight for PBI * FalseWeight for BI.
+ // We assume that total weights of a BranchInst can fit into 32 bits.
+ // Therefore, we will not have overflow using 64-bit arithmetic.
+ NewWeights.push_back(PredFalseWeight *
+ (SuccFalseWeight + SuccTrueWeight) +
+ PredTrueWeight * SuccFalseWeight);
}
-
- // PBI is changed to branch to UniqueSucc below. Remove itself from
- // potential phis from all other successors.
- if (MSSAU)
- MSSAU->changeCondBranchToUnconditionalTo(PBI, UniqueSucc);
-
- // Change PBI from Conditional to Unconditional.
- BranchInst *New_PBI = BranchInst::Create(UniqueSucc, PBI);
- EraseTerminatorAndDCECond(PBI, MSSAU);
- PBI = New_PBI;
+ PBI->setSuccessor(0, UniqueSucc);
+ }
+ if (PBI->getSuccessor(1) == BB) {
+ if (HasWeights) {
+ // PBI: br i1 %x, TrueDest, BB
+ // BI: br i1 %y, TrueDest, UniqueSucc
+ // TrueWeight is TrueWeight for PBI * TotalWeight for BI +
+ // FalseWeight for PBI * TrueWeight for BI.
+ NewWeights.push_back(PredTrueWeight *
+ (SuccFalseWeight + SuccTrueWeight) +
+ PredFalseWeight * SuccTrueWeight);
+ // FalseWeight is FalseWeight for PBI * FalseWeight for BI.
+ NewWeights.push_back(PredFalseWeight * SuccFalseWeight);
+ }
+ PBI->setSuccessor(1, UniqueSucc);
}
+ if (NewWeights.size() == 2) {
+ // Halve the weights if any of them cannot fit in an uint32_t
+ FitWeights(NewWeights);
+
+ SmallVector<uint32_t, 8> MDWeights(NewWeights.begin(), NewWeights.end());
+ setBranchWeights(PBI, MDWeights[0], MDWeights[1]);
+ } else
+ PBI->setMetadata(LLVMContext::MD_prof, nullptr);
if (DTU)
- DTU->applyUpdates(Updates);
+ DTU->applyUpdates({{DominatorTree::Insert, PredBlock, UniqueSucc},
+ {DominatorTree::Delete, PredBlock, BB}});
// If BI was a loop latch, it may have had associated loop metadata.
// We need to copy it to the new latch, that is, PBI.
diff --git a/llvm/test/Transforms/SimplifyCFG/X86/fold-branch-debuginvariant.ll b/llvm/test/Transforms/SimplifyCFG/X86/fold-branch-debuginvariant.ll
deleted file mode 100644
index 44accf871359..000000000000
--- a/llvm/test/Transforms/SimplifyCFG/X86/fold-branch-debuginvariant.ll
+++ /dev/null
@@ -1,48 +0,0 @@
-; RUN: opt < %s -simplifycfg -simplifycfg-require-and-preserve-domtree=1 -S | FileCheck %s
-; RUN: opt < %s -strip-debug -simplifycfg -simplifycfg-require-and-preserve-domtree=1 -S | FileCheck %s
-
-; Verify that the and.2 instruction is eliminated even in the presence of a
-; preceding debug intrinsic.
-
-; CHECK-LABEL: bb1:
-; CHECK: and i1 false, false
-; CHECK-NOT: and i1 false, false
-
-target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
-target triple = "x86_64-unknown-linux-gnu"
-
-; Function Attrs: norecurse nounwind
-define void @foo() local_unnamed_addr #0 !dbg !4 {
-bb1:
- %and.1 = and i1 false, false
- %cmp = icmp eq i16 0, 0
- br i1 %cmp, label %bb2, label %bb3
-
-bb2: ; preds = %bb1
- call void @llvm.dbg.value(metadata i16 0, metadata !8, metadata !DIExpression()), !dbg !9
- %and.2 = and i1 false, false
- br label %bb3
-
-bb3: ; preds = %bb2, %bb1
- ret void
-}
-
-; Function Attrs: nounwind readnone speculatable
-declare void @llvm.dbg.value(metadata, metadata, metadata) #1
-
-attributes #0 = { norecurse nounwind }
-attributes #1 = { nounwind readnone speculatable }
-
-!llvm.dbg.cu = !{!0}
-!llvm.module.flags = !{!3}
-
-!0 = distinct !DICompileUnit(language: DW_LANG_C, file: !1, producer: "Foo", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, retainedTypes: !2, globals: !2)
-!1 = !DIFile(filename: "foo.c", directory: "/")
-!2 = !{}
-!3 = !{i32 2, !"Debug Info Version", i32 3}
-!4 = distinct !DISubprogram(name: "foo", scope: !1, file: !1, line: 10, type: !5, isLocal: false, isDefinition: true, scopeLine: 10, isOptimized: false, unit: !0, retainedNodes: !2)
-!5 = !DISubroutineType(types: !6)
-!6 = !{null, !7}
-!7 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
-!8 = !DILocalVariable(name: "p_1", arg: 1, scope: !4, line: 4, type: !7)
-!9 = distinct !DILocation(line: 11, column: 3, scope: !4)
diff --git a/llvm/test/Transforms/SimplifyCFG/branch-fold.ll b/llvm/test/Transforms/SimplifyCFG/branch-fold.ll
index 5b9f20b97d4e..1caaf16dd591 100644
--- a/llvm/test/Transforms/SimplifyCFG/branch-fold.ll
+++ b/llvm/test/Transforms/SimplifyCFG/branch-fold.ll
@@ -39,12 +39,16 @@ define zeroext i1 @test2(i64 %i0, i64 %i1) nounwind uwtable readonly ssp {
; CHECK-NEXT: [[SHR_I_I:%.*]] = lshr i64 [[I1]], 48
; CHECK-NEXT: [[AND_I2_I:%.*]] = and i64 [[SHR_I_I]], 32767
; CHECK-NEXT: [[CMP9_I:%.*]] = icmp ult i64 [[AND_I5_I]], [[AND_I2_I]]
-; CHECK-NEXT: [[PHITMP:%.*]] = icmp uge i64 [[AND_I2_I]], [[AND_I5_I]]
-; CHECK-NEXT: [[NOT_COND:%.*]] = xor i1 [[CMP9_I]], true
-; CHECK-NEXT: [[AND_COND:%.*]] = and i1 [[NOT_COND]], [[PHITMP]]
+; CHECK-NEXT: br i1 [[CMP9_I]], label [[C]], label [[B:%.*]]
+; CHECK: b:
+; CHECK-NEXT: [[SHR_I13_I9:%.*]] = lshr i64 [[I1]], 48
+; CHECK-NEXT: [[AND_I14_I10:%.*]] = and i64 [[SHR_I13_I9]], 32767
+; CHECK-NEXT: [[SHR_I_I11:%.*]] = lshr i64 [[I0]], 48
+; CHECK-NEXT: [[AND_I11_I12:%.*]] = and i64 [[SHR_I_I11]], 32767
+; CHECK-NEXT: [[PHITMP:%.*]] = icmp uge i64 [[AND_I14_I10]], [[AND_I11_I12]]
; CHECK-NEXT: br label [[C]]
; CHECK: c:
-; CHECK-NEXT: [[O2:%.*]] = phi i1 [ [[AND_COND]], [[A]] ], [ false, [[ENTRY:%.*]] ]
+; CHECK-NEXT: [[O2:%.*]] = phi i1 [ false, [[A]] ], [ [[PHITMP]], [[B]] ], [ false, [[ENTRY:%.*]] ]
; CHECK-NEXT: ret i1 [[O2]]
;
entry:
More information about the llvm-commits
mailing list