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-rw-r--r--contrib/llvm/lib/Transforms/Scalar/GVN.cpp109
1 files changed, 90 insertions, 19 deletions
diff --git a/contrib/llvm/lib/Transforms/Scalar/GVN.cpp b/contrib/llvm/lib/Transforms/Scalar/GVN.cpp
index 2515fd1..87b7317 100644
--- a/contrib/llvm/lib/Transforms/Scalar/GVN.cpp
+++ b/contrib/llvm/lib/Transforms/Scalar/GVN.cpp
@@ -91,6 +91,7 @@ namespace {
uint32_t nextValueNumber;
Expression create_expression(Instruction* I);
+ Expression create_extractvalue_expression(ExtractValueInst* EI);
uint32_t lookup_or_add_call(CallInst* C);
public:
ValueTable() : nextValueNumber(1) { }
@@ -141,7 +142,6 @@ template <> struct DenseMapInfo<Expression> {
// ValueTable Internal Functions
//===----------------------------------------------------------------------===//
-
Expression ValueTable::create_expression(Instruction *I) {
Expression e;
e.type = I->getType();
@@ -150,12 +150,8 @@ Expression ValueTable::create_expression(Instruction *I) {
OI != OE; ++OI)
e.varargs.push_back(lookup_or_add(*OI));
- if (CmpInst *C = dyn_cast<CmpInst>(I))
+ if (CmpInst *C = dyn_cast<CmpInst>(I)) {
e.opcode = (C->getOpcode() << 8) | C->getPredicate();
- else if (ExtractValueInst *E = dyn_cast<ExtractValueInst>(I)) {
- for (ExtractValueInst::idx_iterator II = E->idx_begin(), IE = E->idx_end();
- II != IE; ++II)
- e.varargs.push_back(*II);
} else if (InsertValueInst *E = dyn_cast<InsertValueInst>(I)) {
for (InsertValueInst::idx_iterator II = E->idx_begin(), IE = E->idx_end();
II != IE; ++II)
@@ -165,6 +161,58 @@ Expression ValueTable::create_expression(Instruction *I) {
return e;
}
+Expression ValueTable::create_extractvalue_expression(ExtractValueInst *EI) {
+ assert(EI != 0 && "Not an ExtractValueInst?");
+ Expression e;
+ e.type = EI->getType();
+ e.opcode = 0;
+
+ IntrinsicInst *I = dyn_cast<IntrinsicInst>(EI->getAggregateOperand());
+ if (I != 0 && EI->getNumIndices() == 1 && *EI->idx_begin() == 0 ) {
+ // EI might be an extract from one of our recognised intrinsics. If it
+ // is we'll synthesize a semantically equivalent expression instead on
+ // an extract value expression.
+ switch (I->getIntrinsicID()) {
+ case Intrinsic::sadd_with_overflow:
+ case Intrinsic::uadd_with_overflow:
+ e.opcode = Instruction::Add;
+ break;
+ case Intrinsic::ssub_with_overflow:
+ case Intrinsic::usub_with_overflow:
+ e.opcode = Instruction::Sub;
+ break;
+ case Intrinsic::smul_with_overflow:
+ case Intrinsic::umul_with_overflow:
+ e.opcode = Instruction::Mul;
+ break;
+ default:
+ break;
+ }
+
+ if (e.opcode != 0) {
+ // Intrinsic recognized. Grab its args to finish building the expression.
+ assert(I->getNumArgOperands() == 2 &&
+ "Expect two args for recognised intrinsics.");
+ e.varargs.push_back(lookup_or_add(I->getArgOperand(0)));
+ e.varargs.push_back(lookup_or_add(I->getArgOperand(1)));
+ return e;
+ }
+ }
+
+ // Not a recognised intrinsic. Fall back to producing an extract value
+ // expression.
+ e.opcode = EI->getOpcode();
+ for (Instruction::op_iterator OI = EI->op_begin(), OE = EI->op_end();
+ OI != OE; ++OI)
+ e.varargs.push_back(lookup_or_add(*OI));
+
+ for (ExtractValueInst::idx_iterator II = EI->idx_begin(), IE = EI->idx_end();
+ II != IE; ++II)
+ e.varargs.push_back(*II);
+
+ return e;
+}
+
//===----------------------------------------------------------------------===//
// ValueTable External Functions
//===----------------------------------------------------------------------===//
@@ -227,21 +275,19 @@ uint32_t ValueTable::lookup_or_add_call(CallInst* C) {
// Non-local case.
const MemoryDependenceAnalysis::NonLocalDepInfo &deps =
MD->getNonLocalCallDependency(CallSite(C));
- // FIXME: call/call dependencies for readonly calls should return def, not
- // clobber! Move the checking logic to MemDep!
+ // FIXME: Move the checking logic to MemDep!
CallInst* cdep = 0;
// Check to see if we have a single dominating call instruction that is
// identical to C.
for (unsigned i = 0, e = deps.size(); i != e; ++i) {
const NonLocalDepEntry *I = &deps[i];
- // Ignore non-local dependencies.
if (I->getResult().isNonLocal())
continue;
- // We don't handle non-depedencies. If we already have a call, reject
+ // We don't handle non-definitions. If we already have a call, reject
// instruction dependencies.
- if (I->getResult().isClobber() || cdep != 0) {
+ if (!I->getResult().isDef() || cdep != 0) {
cdep = 0;
break;
}
@@ -338,11 +384,13 @@ uint32_t ValueTable::lookup_or_add(Value *V) {
case Instruction::ExtractElement:
case Instruction::InsertElement:
case Instruction::ShuffleVector:
- case Instruction::ExtractValue:
case Instruction::InsertValue:
case Instruction::GetElementPtr:
exp = create_expression(I);
break;
+ case Instruction::ExtractValue:
+ exp = create_extractvalue_expression(cast<ExtractValueInst>(I));
+ break;
default:
valueNumbering[V] = nextValueNumber;
return nextValueNumber++;
@@ -1192,8 +1240,10 @@ static Value *ConstructSSAForLoadSet(LoadInst *LI,
// escaping uses to any values that are operands to these PHIs.
for (unsigned i = 0, e = NewPHIs.size(); i != e; ++i) {
PHINode *P = NewPHIs[i];
- for (unsigned ii = 0, ee = P->getNumIncomingValues(); ii != ee; ++ii)
- AA->addEscapingUse(P->getOperandUse(2*ii));
+ for (unsigned ii = 0, ee = P->getNumIncomingValues(); ii != ee; ++ii) {
+ unsigned jj = PHINode::getOperandNumForIncomingValue(ii);
+ AA->addEscapingUse(P->getOperandUse(jj));
+ }
}
}
@@ -1224,12 +1274,11 @@ bool GVN::processNonLocalLoad(LoadInst *LI) {
// If we had a phi translation failure, we'll have a single entry which is a
// clobber in the current block. Reject this early.
- if (Deps.size() == 1 && Deps[0].getResult().isClobber() &&
- Deps[0].getResult().getInst()->getParent() == LI->getParent()) {
+ if (Deps.size() == 1 && Deps[0].getResult().isUnknown()) {
DEBUG(
dbgs() << "GVN: non-local load ";
WriteAsOperand(dbgs(), LI);
- dbgs() << " is clobbered by " << *Deps[0].getResult().getInst() << '\n';
+ dbgs() << " has unknown dependencies\n";
);
return false;
}
@@ -1245,6 +1294,11 @@ bool GVN::processNonLocalLoad(LoadInst *LI) {
BasicBlock *DepBB = Deps[i].getBB();
MemDepResult DepInfo = Deps[i].getResult();
+ if (DepInfo.isUnknown()) {
+ UnavailableBlocks.push_back(DepBB);
+ continue;
+ }
+
if (DepInfo.isClobber()) {
// The address being loaded in this non-local block may not be the same as
// the pointer operand of the load if PHI translation occurs. Make sure
@@ -1305,6 +1359,8 @@ bool GVN::processNonLocalLoad(LoadInst *LI) {
continue;
}
+ assert(DepInfo.isDef() && "Expecting def here");
+
Instruction *DepInst = DepInfo.getInst();
// Loading the allocation -> undef.
@@ -1691,10 +1747,22 @@ bool GVN::processLoad(LoadInst *L) {
return false;
}
+ if (Dep.isUnknown()) {
+ DEBUG(
+ // fast print dep, using operator<< on instruction is too slow.
+ dbgs() << "GVN: load ";
+ WriteAsOperand(dbgs(), L);
+ dbgs() << " has unknown dependence\n";
+ );
+ return false;
+ }
+
// If it is defined in another block, try harder.
if (Dep.isNonLocal())
return processNonLocalLoad(L);
+ assert(Dep.isDef() && "Expecting def here");
+
Instruction *DepInst = Dep.getInst();
if (StoreInst *DepSI = dyn_cast<StoreInst>(DepInst)) {
Value *StoredVal = DepSI->getValueOperand();
@@ -2133,8 +2201,11 @@ bool GVN::performPRE(Function &F) {
// Because we have added a PHI-use of the pointer value, it has now
// "escaped" from alias analysis' perspective. We need to inform
// AA of this.
- for (unsigned ii = 0, ee = Phi->getNumIncomingValues(); ii != ee; ++ii)
- VN.getAliasAnalysis()->addEscapingUse(Phi->getOperandUse(2*ii));
+ for (unsigned ii = 0, ee = Phi->getNumIncomingValues(); ii != ee;
+ ++ii) {
+ unsigned jj = PHINode::getOperandNumForIncomingValue(ii);
+ VN.getAliasAnalysis()->addEscapingUse(Phi->getOperandUse(jj));
+ }
if (MD)
MD->invalidateCachedPointerInfo(Phi);
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