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Diffstat (limited to 'contrib/llvm/lib/Transforms/Scalar/GVN.cpp')
-rw-r--r--contrib/llvm/lib/Transforms/Scalar/GVN.cpp79
1 files changed, 29 insertions, 50 deletions
diff --git a/contrib/llvm/lib/Transforms/Scalar/GVN.cpp b/contrib/llvm/lib/Transforms/Scalar/GVN.cpp
index f003e06..129af8d 100644
--- a/contrib/llvm/lib/Transforms/Scalar/GVN.cpp
+++ b/contrib/llvm/lib/Transforms/Scalar/GVN.cpp
@@ -17,11 +17,6 @@
#define DEBUG_TYPE "gvn"
#include "llvm/Transforms/Scalar.h"
-#include "llvm/GlobalVariable.h"
-#include "llvm/IRBuilder.h"
-#include "llvm/IntrinsicInst.h"
-#include "llvm/LLVMContext.h"
-#include "llvm/Metadata.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/DepthFirstIterator.h"
#include "llvm/ADT/Hashing.h"
@@ -37,11 +32,16 @@
#include "llvm/Analysis/PHITransAddr.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/Assembly/Writer.h"
+#include "llvm/IR/DataLayout.h"
+#include "llvm/IR/GlobalVariable.h"
+#include "llvm/IR/IRBuilder.h"
+#include "llvm/IR/IntrinsicInst.h"
+#include "llvm/IR/LLVMContext.h"
+#include "llvm/IR/Metadata.h"
#include "llvm/Support/Allocator.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/PatternMatch.h"
-#include "llvm/DataLayout.h"
#include "llvm/Target/TargetLibraryInfo.h"
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
#include "llvm/Transforms/Utils/SSAUpdater.h"
@@ -849,8 +849,8 @@ static int AnalyzeLoadFromClobberingWrite(Type *LoadTy, Value *LoadPtr,
return -1;
int64_t StoreOffset = 0, LoadOffset = 0;
- Value *StoreBase = GetPointerBaseWithConstantOffset(WritePtr, StoreOffset,TD);
- Value *LoadBase = GetPointerBaseWithConstantOffset(LoadPtr, LoadOffset, TD);
+ Value *StoreBase = GetPointerBaseWithConstantOffset(WritePtr,StoreOffset,&TD);
+ Value *LoadBase = GetPointerBaseWithConstantOffset(LoadPtr, LoadOffset, &TD);
if (StoreBase != LoadBase)
return -1;
@@ -945,7 +945,7 @@ static int AnalyzeLoadFromClobberingLoad(Type *LoadTy, Value *LoadPtr,
// then we should widen it!
int64_t LoadOffs = 0;
const Value *LoadBase =
- GetPointerBaseWithConstantOffset(LoadPtr, LoadOffs, TD);
+ GetPointerBaseWithConstantOffset(LoadPtr, LoadOffs, &TD);
unsigned LoadSize = TD.getTypeStoreSize(LoadTy);
unsigned Size = MemoryDependenceAnalysis::
@@ -1526,10 +1526,8 @@ bool GVN::processNonLocalLoad(LoadInst *LI) {
BasicBlock *LoadBB = LI->getParent();
BasicBlock *TmpBB = LoadBB;
- bool isSinglePred = false;
bool allSingleSucc = true;
while (TmpBB->getSinglePredecessor()) {
- isSinglePred = true;
TmpBB = TmpBB->getSinglePredecessor();
if (TmpBB == LoadBB) // Infinite (unreachable) loop.
return false;
@@ -1548,28 +1546,6 @@ bool GVN::processNonLocalLoad(LoadInst *LI) {
assert(TmpBB);
LoadBB = TmpBB;
- // FIXME: It is extremely unclear what this loop is doing, other than
- // artificially restricting loadpre.
- if (isSinglePred) {
- bool isHot = false;
- for (unsigned i = 0, e = ValuesPerBlock.size(); i != e; ++i) {
- const AvailableValueInBlock &AV = ValuesPerBlock[i];
- if (AV.isSimpleValue())
- // "Hot" Instruction is in some loop (because it dominates its dep.
- // instruction).
- if (Instruction *I = dyn_cast<Instruction>(AV.getSimpleValue()))
- if (DT->dominates(LI, I)) {
- isHot = true;
- break;
- }
- }
-
- // We are interested only in "hot" instructions. We don't want to do any
- // mis-optimizations here.
- if (!isHot)
- return false;
- }
-
// Check to see how many predecessors have the loaded value fully
// available.
DenseMap<BasicBlock*, Value*> PredLoads;
@@ -1738,7 +1714,7 @@ bool GVN::processNonLocalLoad(LoadInst *LI) {
return true;
}
-static void patchReplacementInstruction(Value *Repl, Instruction *I) {
+static void patchReplacementInstruction(Instruction *I, Value *Repl) {
// Patch the replacement so that it is not more restrictive than the value
// being replaced.
BinaryOperator *Op = dyn_cast<BinaryOperator>(I);
@@ -1780,8 +1756,8 @@ static void patchReplacementInstruction(Value *Repl, Instruction *I) {
}
}
-static void patchAndReplaceAllUsesWith(Value *Repl, Instruction *I) {
- patchReplacementInstruction(Repl, I);
+static void patchAndReplaceAllUsesWith(Instruction *I, Value *Repl) {
+ patchReplacementInstruction(I, Repl);
I->replaceAllUsesWith(Repl);
}
@@ -1943,7 +1919,7 @@ bool GVN::processLoad(LoadInst *L) {
}
// Remove it!
- patchAndReplaceAllUsesWith(AvailableVal, L);
+ patchAndReplaceAllUsesWith(L, AvailableVal);
if (DepLI->getType()->getScalarType()->isPointerTy())
MD->invalidateCachedPointerInfo(DepLI);
markInstructionForDeletion(L);
@@ -2284,7 +2260,7 @@ bool GVN::processInstruction(Instruction *I) {
}
// Remove it!
- patchAndReplaceAllUsesWith(repl, I);
+ patchAndReplaceAllUsesWith(I, repl);
if (MD && repl->getType()->getScalarType()->isPointerTy())
MD->invalidateCachedPointerInfo(repl);
markInstructionForDeletion(I);
@@ -2371,8 +2347,8 @@ bool GVN::processBlock(BasicBlock *BB) {
E = InstrsToErase.end(); I != E; ++I) {
DEBUG(dbgs() << "GVN removed: " << **I << '\n');
if (MD) MD->removeInstruction(*I);
- (*I)->eraseFromParent();
DEBUG(verifyRemoved(*I));
+ (*I)->eraseFromParent();
}
InstrsToErase.clear();
@@ -2389,7 +2365,7 @@ bool GVN::processBlock(BasicBlock *BB) {
/// control flow patterns and attempts to perform simple PRE at the join point.
bool GVN::performPRE(Function &F) {
bool Changed = false;
- DenseMap<BasicBlock*, Value*> predMap;
+ SmallVector<std::pair<Value*, BasicBlock*>, 8> predMap;
for (df_iterator<BasicBlock*> DI = df_begin(&F.getEntryBlock()),
DE = df_end(&F.getEntryBlock()); DI != DE; ++DI) {
BasicBlock *CurrentBlock = *DI;
@@ -2445,19 +2421,22 @@ bool GVN::performPRE(Function &F) {
if (P == CurrentBlock) {
NumWithout = 2;
break;
- } else if (!DT->dominates(&F.getEntryBlock(), P)) {
+ } else if (!DT->isReachableFromEntry(P)) {
NumWithout = 2;
break;
}
Value* predV = findLeader(P, ValNo);
if (predV == 0) {
+ predMap.push_back(std::make_pair(static_cast<Value *>(0), P));
PREPred = P;
++NumWithout;
} else if (predV == CurInst) {
+ /* CurInst dominates this predecessor. */
NumWithout = 2;
+ break;
} else {
- predMap[P] = predV;
+ predMap.push_back(std::make_pair(predV, P));
++NumWith;
}
}
@@ -2504,15 +2483,14 @@ bool GVN::performPRE(Function &F) {
// the PRE predecessor. This is typically because of loads which
// are not value numbered precisely.
if (!success) {
- delete PREInstr;
DEBUG(verifyRemoved(PREInstr));
+ delete PREInstr;
continue;
}
PREInstr->insertBefore(PREPred->getTerminator());
PREInstr->setName(CurInst->getName() + ".pre");
PREInstr->setDebugLoc(CurInst->getDebugLoc());
- predMap[PREPred] = PREInstr;
VN.add(PREInstr, ValNo);
++NumGVNPRE;
@@ -2520,13 +2498,14 @@ bool GVN::performPRE(Function &F) {
addToLeaderTable(ValNo, PREInstr, PREPred);
// Create a PHI to make the value available in this block.
- pred_iterator PB = pred_begin(CurrentBlock), PE = pred_end(CurrentBlock);
- PHINode* Phi = PHINode::Create(CurInst->getType(), std::distance(PB, PE),
+ PHINode* Phi = PHINode::Create(CurInst->getType(), predMap.size(),
CurInst->getName() + ".pre-phi",
CurrentBlock->begin());
- for (pred_iterator PI = PB; PI != PE; ++PI) {
- BasicBlock *P = *PI;
- Phi->addIncoming(predMap[P], P);
+ for (unsigned i = 0, e = predMap.size(); i != e; ++i) {
+ if (Value *V = predMap[i].first)
+ Phi->addIncoming(V, predMap[i].second);
+ else
+ Phi->addIncoming(PREInstr, PREPred);
}
VN.add(Phi, ValNo);
@@ -2551,8 +2530,8 @@ bool GVN::performPRE(Function &F) {
DEBUG(dbgs() << "GVN PRE removed: " << *CurInst << '\n');
if (MD) MD->removeInstruction(CurInst);
- CurInst->eraseFromParent();
DEBUG(verifyRemoved(CurInst));
+ CurInst->eraseFromParent();
Changed = true;
}
}
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