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-rw-r--r--lib/Transforms/Utils/LoopSimplify.cpp69
1 files changed, 30 insertions, 39 deletions
diff --git a/lib/Transforms/Utils/LoopSimplify.cpp b/lib/Transforms/Utils/LoopSimplify.cpp
index b3c4801a4f15..246263026bb4 100644
--- a/lib/Transforms/Utils/LoopSimplify.cpp
+++ b/lib/Transforms/Utils/LoopSimplify.cpp
@@ -37,7 +37,7 @@
//
//===----------------------------------------------------------------------===//
-#define DEBUG_TYPE "loopsimplify"
+#define DEBUG_TYPE "loop-simplify"
#include "llvm/Transforms/Scalar.h"
#include "llvm/Constants.h"
#include "llvm/Instructions.h"
@@ -46,9 +46,10 @@
#include "llvm/LLVMContext.h"
#include "llvm/Type.h"
#include "llvm/Analysis/AliasAnalysis.h"
-#include "llvm/Analysis/ScalarEvolution.h"
#include "llvm/Analysis/Dominators.h"
+#include "llvm/Analysis/InstructionSimplify.h"
#include "llvm/Analysis/LoopPass.h"
+#include "llvm/Analysis/ScalarEvolution.h"
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
#include "llvm/Transforms/Utils/Local.h"
#include "llvm/Support/CFG.h"
@@ -65,7 +66,9 @@ STATISTIC(NumNested , "Number of nested loops split out");
namespace {
struct LoopSimplify : public LoopPass {
static char ID; // Pass identification, replacement for typeid
- LoopSimplify() : LoopPass(ID) {}
+ LoopSimplify() : LoopPass(ID) {
+ initializeLoopSimplifyPass(*PassRegistry::getPassRegistry());
+ }
// AA - If we have an alias analysis object to update, this is it, otherwise
// this is null.
@@ -87,8 +90,6 @@ namespace {
AU.addPreserved<AliasAnalysis>();
AU.addPreserved<ScalarEvolution>();
AU.addPreservedID(BreakCriticalEdgesID); // No critical edges added.
- AU.addPreserved<DominanceFrontier>();
- AU.addPreservedID(LCSSAID);
}
/// verifyAnalysis() - Verify LoopSimplifyForm's guarantees.
@@ -107,8 +108,12 @@ namespace {
}
char LoopSimplify::ID = 0;
-INITIALIZE_PASS(LoopSimplify, "loopsimplify",
- "Canonicalize natural loops", true, false);
+INITIALIZE_PASS_BEGIN(LoopSimplify, "loop-simplify",
+ "Canonicalize natural loops", true, false)
+INITIALIZE_PASS_DEPENDENCY(DominatorTree)
+INITIALIZE_PASS_DEPENDENCY(LoopInfo)
+INITIALIZE_PASS_END(LoopSimplify, "loop-simplify",
+ "Canonicalize natural loops", true, false)
// Publically exposed interface to pass...
char &llvm::LoopSimplifyID = LoopSimplify::ID;
@@ -157,9 +162,8 @@ ReprocessLoop:
for (SmallPtrSet<BasicBlock*, 4>::iterator I = BadPreds.begin(),
E = BadPreds.end(); I != E; ++I) {
- DEBUG(dbgs() << "LoopSimplify: Deleting edge from dead predecessor ";
- WriteAsOperand(dbgs(), *I, false);
- dbgs() << "\n");
+ DEBUG(dbgs() << "LoopSimplify: Deleting edge from dead predecessor "
+ << (*I)->getName() << "\n");
// Inform each successor of each dead pred.
for (succ_iterator SI = succ_begin(*I), SE = succ_end(*I); SI != SE; ++SI)
@@ -184,9 +188,8 @@ ReprocessLoop:
if (BI->isConditional()) {
if (UndefValue *Cond = dyn_cast<UndefValue>(BI->getCondition())) {
- DEBUG(dbgs() << "LoopSimplify: Resolving \"br i1 undef\" to exit in ";
- WriteAsOperand(dbgs(), *I, false);
- dbgs() << "\n");
+ DEBUG(dbgs() << "LoopSimplify: Resolving \"br i1 undef\" to exit in "
+ << (*I)->getName() << "\n");
BI->setCondition(ConstantInt::get(Cond->getType(),
!L->contains(BI->getSuccessor(0))));
@@ -262,8 +265,9 @@ ReprocessLoop:
PHINode *PN;
for (BasicBlock::iterator I = L->getHeader()->begin();
(PN = dyn_cast<PHINode>(I++)); )
- if (Value *V = PN->hasConstantValue(DT)) {
+ if (Value *V = SimplifyInstruction(PN, 0, DT)) {
if (AA) AA->deleteValue(PN);
+ if (SE) SE->forgetValue(PN);
PN->replaceAllUsesWith(V);
PN->eraseFromParent();
}
@@ -317,29 +321,22 @@ ReprocessLoop:
if (!FoldBranchToCommonDest(BI)) continue;
// Success. The block is now dead, so remove it from the loop,
- // update the dominator tree and dominance frontier, and delete it.
-
- DEBUG(dbgs() << "LoopSimplify: Eliminating exiting block ";
- WriteAsOperand(dbgs(), ExitingBlock, false);
- dbgs() << "\n");
+ // update the dominator tree and delete it.
+ DEBUG(dbgs() << "LoopSimplify: Eliminating exiting block "
+ << ExitingBlock->getName() << "\n");
assert(pred_begin(ExitingBlock) == pred_end(ExitingBlock));
Changed = true;
LI->removeBlock(ExitingBlock);
- DominanceFrontier *DF = getAnalysisIfAvailable<DominanceFrontier>();
DomTreeNode *Node = DT->getNode(ExitingBlock);
const std::vector<DomTreeNodeBase<BasicBlock> *> &Children =
Node->getChildren();
while (!Children.empty()) {
DomTreeNode *Child = Children.front();
DT->changeImmediateDominator(Child, Node->getIDom());
- if (DF) DF->changeImmediateDominator(Child->getBlock(),
- Node->getIDom()->getBlock(),
- DT);
}
DT->eraseNode(ExitingBlock);
- if (DF) DF->removeBlock(ExitingBlock);
BI->getSuccessor(0)->removePredecessor(ExitingBlock);
BI->getSuccessor(1)->removePredecessor(ExitingBlock);
@@ -378,9 +375,8 @@ BasicBlock *LoopSimplify::InsertPreheaderForLoop(Loop *L) {
SplitBlockPredecessors(Header, &OutsideBlocks[0], OutsideBlocks.size(),
".preheader", this);
- DEBUG(dbgs() << "LoopSimplify: Creating pre-header ";
- WriteAsOperand(dbgs(), NewBB, false);
- dbgs() << "\n");
+ DEBUG(dbgs() << "LoopSimplify: Creating pre-header " << NewBB->getName()
+ << "\n");
// Make sure that NewBB is put someplace intelligent, which doesn't mess up
// code layout too horribly.
@@ -409,10 +405,8 @@ BasicBlock *LoopSimplify::RewriteLoopExitBlock(Loop *L, BasicBlock *Exit) {
LoopBlocks.size(), ".loopexit",
this);
- DEBUG(dbgs() << "LoopSimplify: Creating dedicated exit block ";
- WriteAsOperand(dbgs(), NewBB, false);
- dbgs() << "\n");
-
+ DEBUG(dbgs() << "LoopSimplify: Creating dedicated exit block "
+ << NewBB->getName() << "\n");
return NewBB;
}
@@ -438,11 +432,11 @@ static void AddBlockAndPredsToSet(BasicBlock *InputBB, BasicBlock *StopBlock,
/// FindPHIToPartitionLoops - The first part of loop-nestification is to find a
/// PHI node that tells us how to partition the loops.
static PHINode *FindPHIToPartitionLoops(Loop *L, DominatorTree *DT,
- AliasAnalysis *AA) {
+ AliasAnalysis *AA, LoopInfo *LI) {
for (BasicBlock::iterator I = L->getHeader()->begin(); isa<PHINode>(I); ) {
PHINode *PN = cast<PHINode>(I);
++I;
- if (Value *V = PN->hasConstantValue(DT)) {
+ if (Value *V = SimplifyInstruction(PN, 0, DT)) {
// This is a degenerate PHI already, don't modify it!
PN->replaceAllUsesWith(V);
if (AA) AA->deleteValue(PN);
@@ -516,7 +510,7 @@ void LoopSimplify::PlaceSplitBlockCarefully(BasicBlock *NewBB,
/// created.
///
Loop *LoopSimplify::SeparateNestedLoop(Loop *L, LPPassManager &LPM) {
- PHINode *PN = FindPHIToPartitionLoops(L, DT, AA);
+ PHINode *PN = FindPHIToPartitionLoops(L, DT, AA, LI);
if (PN == 0) return 0; // No known way to partition.
// Pull out all predecessors that have varying values in the loop. This
@@ -643,9 +637,8 @@ LoopSimplify::InsertUniqueBackedgeBlock(Loop *L, BasicBlock *Preheader) {
Header->getName()+".backedge", F);
BranchInst *BETerminator = BranchInst::Create(Header, BEBlock);
- DEBUG(dbgs() << "LoopSimplify: Inserting unique backedge block ";
- WriteAsOperand(dbgs(), BEBlock, false);
- dbgs() << "\n");
+ DEBUG(dbgs() << "LoopSimplify: Inserting unique backedge block "
+ << BEBlock->getName() << "\n");
// Move the new backedge block to right after the last backedge block.
Function::iterator InsertPos = BackedgeBlocks.back(); ++InsertPos;
@@ -721,8 +714,6 @@ LoopSimplify::InsertUniqueBackedgeBlock(Loop *L, BasicBlock *Preheader) {
// Update dominator information
DT->splitBlock(BEBlock);
- if (DominanceFrontier *DF = getAnalysisIfAvailable<DominanceFrontier>())
- DF->splitBlock(BEBlock);
return BEBlock;
}
generated by cgit v1.2.3 (git 2.25.1) at 2025-11-04 04:14:41 +0000