//
// The LLVM Compiler Infrastructure
//
-// This file was developed by the LLVM research group and is distributed under
-// the University of Illinois Open Source License. See LICENSE.TXT for details.
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This pass promotes "by reference" arguments to be "by value" arguments. In
// practice, this means looking for internal functions that have pointer
-// arguments. If we can prove, through the use of alias analysis, that an
-// argument is *only* loaded, then we can pass the value into the function
+// arguments. If it can prove, through the use of alias analysis, that an
+// argument is *only* loaded, then it can pass the value into the function
// instead of the address of the value. This can cause recursive simplification
// of code and lead to the elimination of allocas (especially in C++ template
// code like the STL).
//
// This pass also handles aggregate arguments that are passed into a function,
// scalarizing them if the elements of the aggregate are only loaded. Note that
-// we refuse to scalarize aggregates which would require passing in more than
-// three operands to the function, because we don't want to pass thousands of
-// operands for a large array or structure!
+// it refuses to scalarize aggregates which would require passing in more than
+// three operands to the function, because passing thousands of operands for a
+// large array or structure is unprofitable!
//
// Note that this transformation could also be done for arguments that are only
-// stored to (returning the value instead), but we do not currently handle that
-// case. This case would be best handled when and if we start supporting
-// multiple return values from functions.
+// stored to (returning the value instead), but does not currently. This case
+// would be best handled when and if LLVM begins supporting multiple return
+// values from functions.
//
//===----------------------------------------------------------------------===//
#include "llvm/Module.h"
#include "llvm/CallGraphSCCPass.h"
#include "llvm/Instructions.h"
+#include "llvm/ParameterAttributes.h"
#include "llvm/Analysis/AliasAnalysis.h"
#include "llvm/Analysis/CallGraph.h"
#include "llvm/Target/TargetData.h"
STATISTIC(NumArgumentsPromoted , "Number of pointer arguments promoted");
STATISTIC(NumAggregatesPromoted, "Number of aggregate arguments promoted");
+STATISTIC(NumByValArgsPromoted , "Number of byval arguments promoted");
STATISTIC(NumArgumentsDead , "Number of dead pointer args eliminated");
namespace {
private:
bool PromoteArguments(CallGraphNode *CGN);
- bool isSafeToPromoteArgument(Argument *Arg) const;
- Function *DoPromotion(Function *F, std::vector<Argument*> &ArgsToPromote);
+ bool isSafeToPromoteArgument(Argument *Arg, bool isByVal) const;
+ Function *DoPromotion(Function *F,
+ SmallPtrSet<Argument*, 8> &ArgsToPromote,
+ SmallPtrSet<Argument*, 8> &ByValArgsToTransform);
};
char ArgPromotion::ID = 0;
if (!F || !F->hasInternalLinkage()) return false;
// First check: see if there are any pointer arguments! If not, quick exit.
- std::vector<Argument*> PointerArgs;
- for (Function::arg_iterator I = F->arg_begin(), E = F->arg_end(); I != E; ++I)
+ SmallVector<std::pair<Argument*, unsigned>, 16> PointerArgs;
+ unsigned ArgNo = 0;
+ for (Function::arg_iterator I = F->arg_begin(), E = F->arg_end();
+ I != E; ++I, ++ArgNo)
if (isa<PointerType>(I->getType()))
- PointerArgs.push_back(I);
+ PointerArgs.push_back(std::pair<Argument*, unsigned>(I, ArgNo));
if (PointerArgs.empty()) return false;
// Second check: make sure that all callers are direct callers. We can't
// Ensure that this call site is CALLING the function, not passing it as
// an argument.
- for (CallSite::arg_iterator AI = CS.arg_begin(), E = CS.arg_end();
- AI != E; ++AI)
- if (*AI == F) return false; // Passing the function address in!
+ if (UI.getOperandNo() != 0)
+ return false;
}
- // Check to see which arguments are promotable. If an argument is not
- // promotable, remove it from the PointerArgs vector.
- for (unsigned i = 0; i != PointerArgs.size(); ++i)
- if (!isSafeToPromoteArgument(PointerArgs[i])) {
- std::swap(PointerArgs[i--], PointerArgs.back());
- PointerArgs.pop_back();
+ // Check to see which arguments are promotable. If an argument is promotable,
+ // add it to ArgsToPromote.
+ SmallPtrSet<Argument*, 8> ArgsToPromote;
+ SmallPtrSet<Argument*, 8> ByValArgsToTransform;
+ for (unsigned i = 0; i != PointerArgs.size(); ++i) {
+ bool isByVal = F->paramHasAttr(PointerArgs[i].second+1, ParamAttr::ByVal);
+
+ // If this is a byval argument, and if the aggregate type is small, just
+ // pass the elements, which is always safe.
+ Argument *PtrArg = PointerArgs[i].first;
+ if (isByVal) {
+ const Type *AgTy = cast<PointerType>(PtrArg->getType())->getElementType();
+ if (const StructType *STy = dyn_cast<StructType>(AgTy))
+ if (STy->getNumElements() <= 3) {
+ // If all the elements are first class types, we can promote it.
+ bool AllSimple = true;
+ for (unsigned i = 0, e = STy->getNumElements(); i != e; ++i)
+ if (!STy->getElementType(i)->isFirstClassType()) {
+ AllSimple = false;
+ break;
+ }
+
+ // Safe to transform, don't even bother trying to "promote" it.
+ // Passing the elements as a scalar will allow scalarrepl to hack on
+ // the new alloca we introduce.
+ if (AllSimple) {
+ ByValArgsToTransform.insert(PtrArg);
+ continue;
+ }
+ }
}
-
+
+ // Otherwise, see if we can promote the pointer to its value.
+ if (isSafeToPromoteArgument(PtrArg, isByVal))
+ ArgsToPromote.insert(PtrArg);
+ }
+
// No promotable pointer arguments.
- if (PointerArgs.empty()) return false;
+ if (ArgsToPromote.empty() && ByValArgsToTransform.empty()) return false;
- // Okay, promote all of the arguments are rewrite the callees!
- Function *NewF = DoPromotion(F, PointerArgs);
+ Function *NewF = DoPromotion(F, ArgsToPromote, ByValArgsToTransform);
- // Update the call graph to know that the old function is gone.
+ // Update the call graph to know that the function has been transformed.
getAnalysis<CallGraph>().changeFunction(F, NewF);
return true;
}
/// This method limits promotion of aggregates to only promote up to three
/// elements of the aggregate in order to avoid exploding the number of
/// arguments passed in.
-bool ArgPromotion::isSafeToPromoteArgument(Argument *Arg) const {
+bool ArgPromotion::isSafeToPromoteArgument(Argument *Arg, bool isByVal) const {
// We can only promote this argument if all of the uses are loads, or are GEP
// instructions (with constant indices) that are subsequently loaded.
- bool HasLoadInEntryBlock = false;
+
+ // We can also only promote the load if we can guarantee that it will happen.
+ // Promoting a load causes the load to be unconditionally executed in the
+ // caller, so we can't turn a conditional load into an unconditional load in
+ // general.
+ bool SafeToUnconditionallyLoad = false;
+ if (isByVal) // ByVal arguments are always safe to load from.
+ SafeToUnconditionallyLoad = true;
+
BasicBlock *EntryBlock = Arg->getParent()->begin();
- std::vector<LoadInst*> Loads;
- std::vector<std::vector<ConstantInt*> > GEPIndices;
+ SmallVector<LoadInst*, 16> Loads;
+ std::vector<SmallVector<ConstantInt*, 8> > GEPIndices;
for (Value::use_iterator UI = Arg->use_begin(), E = Arg->use_end();
UI != E; ++UI)
if (LoadInst *LI = dyn_cast<LoadInst>(*UI)) {
if (LI->isVolatile()) return false; // Don't hack volatile loads
Loads.push_back(LI);
- HasLoadInEntryBlock |= LI->getParent() == EntryBlock;
+
+ // If this load occurs in the entry block, then the pointer is
+ // unconditionally loaded.
+ SafeToUnconditionallyLoad |= LI->getParent() == EntryBlock;
} else if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(*UI)) {
if (GEP->use_empty()) {
// Dead GEP's cause trouble later. Just remove them if we run into
// them.
getAnalysis<AliasAnalysis>().deleteValue(GEP);
- GEP->getParent()->getInstList().erase(GEP);
- return isSafeToPromoteArgument(Arg);
+ GEP->eraseFromParent();
+ return isSafeToPromoteArgument(Arg, isByVal);
}
// Ensure that all of the indices are constants.
- std::vector<ConstantInt*> Operands;
+ SmallVector<ConstantInt*, 8> Operands;
for (unsigned i = 1, e = GEP->getNumOperands(); i != e; ++i)
if (ConstantInt *C = dyn_cast<ConstantInt>(GEP->getOperand(i)))
Operands.push_back(C);
if (LoadInst *LI = dyn_cast<LoadInst>(*UI)) {
if (LI->isVolatile()) return false; // Don't hack volatile loads
Loads.push_back(LI);
- HasLoadInEntryBlock |= LI->getParent() == EntryBlock;
+
+ // If this load occurs in the entry block, then the pointer is
+ // unconditionally loaded.
+ SafeToUnconditionallyLoad |= LI->getParent() == EntryBlock;
} else {
return false;
}
// of the pointer in the entry block of the function) or if we can prove that
// all pointers passed in are always to legal locations (for example, no null
// pointers are passed in, no pointers to free'd memory, etc).
- if (!HasLoadInEntryBlock && !AllCalleesPassInValidPointerForArgument(Arg))
+ if (!SafeToUnconditionallyLoad &&
+ !AllCalleesPassInValidPointerForArgument(Arg))
return false; // Cannot prove that this is safe!!
// Okay, now we know that the argument is only used by load instructions and
// Because there could be several/many load instructions, remember which
// blocks we know to be transparent to the load.
- std::set<BasicBlock*> TranspBlocks;
+ SmallPtrSet<BasicBlock*, 16> TranspBlocks;
AliasAnalysis &AA = getAnalysis<AliasAnalysis>();
TargetData &TD = getAnalysis<TargetData>();
const PointerType *LoadTy =
cast<PointerType>(Load->getOperand(0)->getType());
- unsigned LoadSize = (unsigned)TD.getTypeSize(LoadTy->getElementType());
+ unsigned LoadSize = (unsigned)TD.getTypeStoreSize(LoadTy->getElementType());
if (AA.canInstructionRangeModify(BB->front(), *Load, Arg, LoadSize))
return false; // Pointer is invalidated!
// To do this, we perform a depth first search on the inverse CFG from the
// loading block.
for (pred_iterator PI = pred_begin(BB), E = pred_end(BB); PI != E; ++PI)
- for (idf_ext_iterator<BasicBlock*> I = idf_ext_begin(*PI, TranspBlocks),
+ for (idf_ext_iterator<BasicBlock*, SmallPtrSet<BasicBlock*, 16> >
+ I = idf_ext_begin(*PI, TranspBlocks),
E = idf_ext_end(*PI, TranspBlocks); I != E; ++I)
if (AA.canBasicBlockModify(**I, Arg, LoadSize))
return false;
/// arguments, and returns the new function. At this point, we know that it's
/// safe to do so.
Function *ArgPromotion::DoPromotion(Function *F,
- std::vector<Argument*> &Args2Prom) {
- std::set<Argument*> ArgsToPromote(Args2Prom.begin(), Args2Prom.end());
+ SmallPtrSet<Argument*, 8> &ArgsToPromote,
+ SmallPtrSet<Argument*, 8> &ByValArgsToTransform) {
// Start by computing a new prototype for the function, which is the same as
// the old function, but has modified arguments.
// what the new GEP/Load instructions we are inserting look like.
std::map<std::vector<Value*>, LoadInst*> OriginalLoads;
- for (Function::arg_iterator I = F->arg_begin(), E = F->arg_end(); I != E; ++I)
- if (!ArgsToPromote.count(I)) {
+ // ParamAttrs - Keep track of the parameter attributes for the arguments
+ // that we are *not* promoting. For the ones that we do promote, the parameter
+ // attributes are lost
+ ParamAttrsVector ParamAttrsVec;
+ const ParamAttrsList *PAL = F->getParamAttrs();
+
+ // Add any return attributes.
+ if (unsigned attrs = PAL ? PAL->getParamAttrs(0) : 0)
+ ParamAttrsVec.push_back(ParamAttrsWithIndex::get(0, attrs));
+
+ unsigned ArgIndex = 1;
+ for (Function::arg_iterator I = F->arg_begin(), E = F->arg_end(); I != E;
+ ++I, ++ArgIndex) {
+ if (ByValArgsToTransform.count(I)) {
+ // Just add all the struct element types.
+ const Type *AgTy = cast<PointerType>(I->getType())->getElementType();
+ const StructType *STy = cast<StructType>(AgTy);
+ for (unsigned i = 0, e = STy->getNumElements(); i != e; ++i)
+ Params.push_back(STy->getElementType(i));
+ ++NumByValArgsPromoted;
+ } else if (!ArgsToPromote.count(I)) {
Params.push_back(I->getType());
+ if (unsigned attrs = PAL ? PAL->getParamAttrs(ArgIndex) : 0)
+ ParamAttrsVec.push_back(ParamAttrsWithIndex::get(Params.size(), attrs));
} else if (I->use_empty()) {
++NumArgumentsDead;
} else {
for (ScalarizeTable::iterator SI = ArgIndices.begin(),
E = ArgIndices.end(); SI != E; ++SI)
Params.push_back(GetElementPtrInst::getIndexedType(I->getType(),
- &(*SI)[0],
- SI->size()));
+ SI->begin(),
+ SI->end()));
if (ArgIndices.size() == 1 && ArgIndices.begin()->empty())
++NumArgumentsPromoted;
else
++NumAggregatesPromoted;
}
+ }
const Type *RetTy = FTy->getReturnType();
ExtraArgHack = true;
Params.push_back(Type::Int32Ty);
}
+
+ // Construct the new function type using the new arguments.
FunctionType *NFTy = FunctionType::get(RetTy, Params, FTy->isVarArg());
- // Create the new function body and insert it into the module...
+ // Create the new function body and insert it into the module...
Function *NF = new Function(NFTy, F->getLinkage(), F->getName());
NF->setCallingConv(F->getCallingConv());
+
+ // Recompute the parameter attributes list based on the new arguments for
+ // the function.
+ NF->setParamAttrs(ParamAttrsList::get(ParamAttrsVec));
+ ParamAttrsVec.clear(); PAL = 0;
+
+ if (F->hasCollector())
+ NF->setCollector(F->getCollector());
F->getParent()->getFunctionList().insert(F, NF);
// Get the alias analysis information that we need to update to reflect our
// Loop over all of the callers of the function, transforming the call sites
// to pass in the loaded pointers.
//
- std::vector<Value*> Args;
+ SmallVector<Value*, 16> Args;
while (!F->use_empty()) {
CallSite CS = CallSite::get(F->use_back());
Instruction *Call = CS.getInstruction();
+ PAL = CS.getParamAttrs();
+
+ // Add any return attributes.
+ if (unsigned attrs = PAL ? PAL->getParamAttrs(0) : 0)
+ ParamAttrsVec.push_back(ParamAttrsWithIndex::get(0, attrs));
// Loop over the operands, inserting GEP and loads in the caller as
// appropriate.
CallSite::arg_iterator AI = CS.arg_begin();
+ ArgIndex = 1;
for (Function::arg_iterator I = F->arg_begin(), E = F->arg_end();
- I != E; ++I, ++AI)
- if (!ArgsToPromote.count(I))
+ I != E; ++I, ++AI, ++ArgIndex)
+ if (!ArgsToPromote.count(I) && !ByValArgsToTransform.count(I)) {
Args.push_back(*AI); // Unmodified argument
- else if (!I->use_empty()) {
+
+ if (unsigned Attrs = PAL ? PAL->getParamAttrs(ArgIndex) : 0)
+ ParamAttrsVec.push_back(ParamAttrsWithIndex::get(Args.size(), Attrs));
+
+ } else if (ByValArgsToTransform.count(I)) {
+ // Emit a GEP and load for each element of the struct.
+ const Type *AgTy = cast<PointerType>(I->getType())->getElementType();
+ const StructType *STy = cast<StructType>(AgTy);
+ Value *Idxs[2] = { ConstantInt::get(Type::Int32Ty, 0), 0 };
+ for (unsigned i = 0, e = STy->getNumElements(); i != e; ++i) {
+ Idxs[1] = ConstantInt::get(Type::Int32Ty, i);
+ Value *Idx = new GetElementPtrInst(*AI, Idxs, Idxs+2,
+ (*AI)->getName()+"."+utostr(i),
+ Call);
+ // TODO: Tell AA about the new values?
+ Args.push_back(new LoadInst(Idx, Idx->getName()+".val", Call));
+ }
+ } else if (!I->use_empty()) {
// Non-dead argument: insert GEPs and loads as appropriate.
ScalarizeTable &ArgIndices = ScalarizedElements[I];
for (ScalarizeTable::iterator SI = ArgIndices.begin(),
Value *V = *AI;
LoadInst *OrigLoad = OriginalLoads[*SI];
if (!SI->empty()) {
- V = new GetElementPtrInst(V, &(*SI)[0], SI->size(),
+ V = new GetElementPtrInst(V, SI->begin(), SI->end(),
V->getName()+".idx", Call);
AA.copyValue(OrigLoad->getOperand(0), V);
}
Args.push_back(Constant::getNullValue(Type::Int32Ty));
// Push any varargs arguments on the list
- for (; AI != CS.arg_end(); ++AI)
+ for (; AI != CS.arg_end(); ++AI, ++ArgIndex) {
Args.push_back(*AI);
+ if (unsigned Attrs = PAL ? PAL->getParamAttrs(ArgIndex) : 0)
+ ParamAttrsVec.push_back(ParamAttrsWithIndex::get(Args.size(), Attrs));
+ }
Instruction *New;
if (InvokeInst *II = dyn_cast<InvokeInst>(Call)) {
New = new InvokeInst(NF, II->getNormalDest(), II->getUnwindDest(),
- &Args[0], Args.size(), "", Call);
+ Args.begin(), Args.end(), "", Call);
cast<InvokeInst>(New)->setCallingConv(CS.getCallingConv());
+ cast<InvokeInst>(New)->setParamAttrs(ParamAttrsList::get(ParamAttrsVec));
} else {
New = new CallInst(NF, Args.begin(), Args.end(), "", Call);
cast<CallInst>(New)->setCallingConv(CS.getCallingConv());
+ cast<CallInst>(New)->setParamAttrs(ParamAttrsList::get(ParamAttrsVec));
if (cast<CallInst>(Call)->isTailCall())
cast<CallInst>(New)->setTailCall();
}
Args.clear();
+ ParamAttrsVec.clear();
// Update the alias analysis implementation to know that we are replacing
// the old call with a new one.
// Finally, remove the old call from the program, reducing the use-count of
// F.
- Call->getParent()->getInstList().erase(Call);
+ Call->eraseFromParent();
}
// Since we have now created the new function, splice the body of the old
// the new arguments, also transfering over the names as well.
//
for (Function::arg_iterator I = F->arg_begin(), E = F->arg_end(),
- I2 = NF->arg_begin(); I != E; ++I)
- if (!ArgsToPromote.count(I)) {
+ I2 = NF->arg_begin(); I != E; ++I) {
+ if (!ArgsToPromote.count(I) && !ByValArgsToTransform.count(I)) {
// If this is an unmodified argument, move the name and users over to the
// new version.
I->replaceAllUsesWith(I2);
I2->takeName(I);
AA.replaceWithNewValue(I, I2);
++I2;
- } else if (I->use_empty()) {
+ continue;
+ }
+
+ if (ByValArgsToTransform.count(I)) {
+ // In the callee, we create an alloca, and store each of the new incoming
+ // arguments into the alloca.
+ Instruction *InsertPt = NF->begin()->begin();
+
+ // Just add all the struct element types.
+ const Type *AgTy = cast<PointerType>(I->getType())->getElementType();
+ Value *TheAlloca = new AllocaInst(AgTy, 0, "", InsertPt);
+ const StructType *STy = cast<StructType>(AgTy);
+ Value *Idxs[2] = { ConstantInt::get(Type::Int32Ty, 0), 0 };
+
+ for (unsigned i = 0, e = STy->getNumElements(); i != e; ++i) {
+ Idxs[1] = ConstantInt::get(Type::Int32Ty, i);
+ Value *Idx = new GetElementPtrInst(TheAlloca, Idxs, Idxs+2,
+ TheAlloca->getName()+"."+utostr(i),
+ InsertPt);
+ I2->setName(I->getName()+"."+utostr(i));
+ new StoreInst(I2++, Idx, InsertPt);
+ }
+
+ // Anything that used the arg should now use the alloca.
+ I->replaceAllUsesWith(TheAlloca);
+ TheAlloca->takeName(I);
+ AA.replaceWithNewValue(I, TheAlloca);
+ continue;
+ }
+
+ if (I->use_empty()) {
AA.deleteValue(I);
- } else {
- // Otherwise, if we promoted this argument, then all users are load
- // instructions, and all loads should be using the new argument that we
- // added.
- ScalarizeTable &ArgIndices = ScalarizedElements[I];
-
- while (!I->use_empty()) {
- if (LoadInst *LI = dyn_cast<LoadInst>(I->use_back())) {
- assert(ArgIndices.begin()->empty() &&
- "Load element should sort to front!");
- I2->setName(I->getName()+".val");
- LI->replaceAllUsesWith(I2);
- AA.replaceWithNewValue(LI, I2);
- LI->getParent()->getInstList().erase(LI);
- DOUT << "*** Promoted load of argument '" << I->getName()
- << "' in function '" << F->getName() << "'\n";
- } else {
- GetElementPtrInst *GEP = cast<GetElementPtrInst>(I->use_back());
- std::vector<Value*> Operands(GEP->op_begin()+1, GEP->op_end());
-
- Function::arg_iterator TheArg = I2;
- for (ScalarizeTable::iterator It = ArgIndices.begin();
- *It != Operands; ++It, ++TheArg) {
- assert(It != ArgIndices.end() && "GEP not handled??");
- }
+ continue;
+ }
+
+ // Otherwise, if we promoted this argument, then all users are load
+ // instructions, and all loads should be using the new argument that we
+ // added.
+ ScalarizeTable &ArgIndices = ScalarizedElements[I];
+
+ while (!I->use_empty()) {
+ if (LoadInst *LI = dyn_cast<LoadInst>(I->use_back())) {
+ assert(ArgIndices.begin()->empty() &&
+ "Load element should sort to front!");
+ I2->setName(I->getName()+".val");
+ LI->replaceAllUsesWith(I2);
+ AA.replaceWithNewValue(LI, I2);
+ LI->eraseFromParent();
+ DOUT << "*** Promoted load of argument '" << I->getName()
+ << "' in function '" << F->getName() << "'\n";
+ } else {
+ GetElementPtrInst *GEP = cast<GetElementPtrInst>(I->use_back());
+ std::vector<Value*> Operands(GEP->op_begin()+1, GEP->op_end());
+
+ Function::arg_iterator TheArg = I2;
+ for (ScalarizeTable::iterator It = ArgIndices.begin();
+ *It != Operands; ++It, ++TheArg) {
+ assert(It != ArgIndices.end() && "GEP not handled??");
+ }
- std::string NewName = I->getName();
- for (unsigned i = 0, e = Operands.size(); i != e; ++i)
- if (ConstantInt *CI = dyn_cast<ConstantInt>(Operands[i]))
- NewName += "." + CI->getValue().toString(10);
- else
- NewName += ".x";
- TheArg->setName(NewName+".val");
-
- DOUT << "*** Promoted agg argument '" << TheArg->getName()
- << "' of function '" << F->getName() << "'\n";
-
- // All of the uses must be load instructions. Replace them all with
- // the argument specified by ArgNo.
- while (!GEP->use_empty()) {
- LoadInst *L = cast<LoadInst>(GEP->use_back());
- L->replaceAllUsesWith(TheArg);
- AA.replaceWithNewValue(L, TheArg);
- L->getParent()->getInstList().erase(L);
- }
- AA.deleteValue(GEP);
- GEP->getParent()->getInstList().erase(GEP);
+ std::string NewName = I->getName();
+ for (unsigned i = 0, e = Operands.size(); i != e; ++i)
+ if (ConstantInt *CI = dyn_cast<ConstantInt>(Operands[i]))
+ NewName += "." + CI->getValue().toStringUnsigned(10);
+ else
+ NewName += ".x";
+ TheArg->setName(NewName+".val");
+
+ DOUT << "*** Promoted agg argument '" << TheArg->getName()
+ << "' of function '" << F->getName() << "'\n";
+
+ // All of the uses must be load instructions. Replace them all with
+ // the argument specified by ArgNo.
+ while (!GEP->use_empty()) {
+ LoadInst *L = cast<LoadInst>(GEP->use_back());
+ L->replaceAllUsesWith(TheArg);
+ AA.replaceWithNewValue(L, TheArg);
+ L->eraseFromParent();
}
+ AA.deleteValue(GEP);
+ GEP->eraseFromParent();
}
-
- // Increment I2 past all of the arguments added for this promoted pointer.
- for (unsigned i = 0, e = ArgIndices.size(); i != e; ++i)
- ++I2;
}
+ // Increment I2 past all of the arguments added for this promoted pointer.
+ for (unsigned i = 0, e = ArgIndices.size(); i != e; ++i)
+ ++I2;
+ }
+
// Notify the alias analysis implementation that we inserted a new argument.
if (ExtraArgHack)
AA.copyValue(Constant::getNullValue(Type::Int32Ty), NF->arg_begin());
AA.replaceWithNewValue(F, NF);
// Now that the old function is dead, delete it.
- F->getParent()->getFunctionList().erase(F);
+ F->eraseFromParent();
return NF;
}