-//===-- ArgumentPromotion.cpp - Promote 'by reference' arguments ----------===//
-//
+//===-- ArgumentPromotion.cpp - Promote by-reference arguments ------------===//
+//
// 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 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 that an
+// 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
// 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.
+// 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 something!
+// operands for a large array or structure!
//
// 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
//
//===----------------------------------------------------------------------===//
+#define DEBUG_TYPE "argpromotion"
#include "llvm/Transforms/IPO.h"
#include "llvm/Constants.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Module.h"
-#include "llvm/Pass.h"
+#include "llvm/CallGraphSCCPass.h"
#include "llvm/Instructions.h"
#include "llvm/Analysis/AliasAnalysis.h"
+#include "llvm/Analysis/CallGraph.h"
#include "llvm/Target/TargetData.h"
#include "llvm/Support/CallSite.h"
#include "llvm/Support/CFG.h"
-#include "Support/Debug.h"
-#include "Support/DepthFirstIterator.h"
-#include "Support/Statistic.h"
-#include "Support/StringExtras.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/ADT/DepthFirstIterator.h"
+#include "llvm/ADT/Statistic.h"
+#include "llvm/ADT/StringExtras.h"
+#include "llvm/Support/Compiler.h"
#include <set>
using namespace llvm;
-namespace {
- Statistic<> NumArgumentsPromoted("argpromotion",
- "Number of pointer arguments promoted");
- Statistic<> NumAggregatesPromoted("argpromotion",
- "Number of aggregate arguments promoted");
- Statistic<> NumArgumentsDead("argpromotion",
- "Number of dead pointer args eliminated");
+STATISTIC(NumArgumentsPromoted , "Number of pointer arguments promoted");
+STATISTIC(NumAggregatesPromoted, "Number of aggregate arguments promoted");
+STATISTIC(NumArgumentsDead , "Number of dead pointer args eliminated");
+namespace {
/// ArgPromotion - The 'by reference' to 'by value' argument promotion pass.
///
- class ArgPromotion : public Pass {
- // WorkList - The set of internal functions that we have yet to process. As
- // we eliminate arguments from a function, we push all callers into this set
- // so that the by reference argument can be bubbled out as far as possible.
- // This set contains only internal functions.
- std::set<Function*> WorkList;
- public:
+ struct VISIBILITY_HIDDEN ArgPromotion : public CallGraphSCCPass {
virtual void getAnalysisUsage(AnalysisUsage &AU) const {
AU.addRequired<AliasAnalysis>();
AU.addRequired<TargetData>();
+ CallGraphSCCPass::getAnalysisUsage(AU);
}
- virtual bool run(Module &M);
+ virtual bool runOnSCC(const std::vector<CallGraphNode *> &SCC);
+ static char ID; // Pass identification, replacement for typeid
+ ArgPromotion() : CallGraphSCCPass((intptr_t)&ID) {}
+
private:
- bool PromoteArguments(Function *F);
- bool isSafeToPromoteArgument(Argument *Arg) const;
- void DoPromotion(Function *F, std::vector<Argument*> &ArgsToPromote);
+ bool PromoteArguments(CallGraphNode *CGN);
+ bool isSafeToPromoteArgument(Argument *Arg) const;
+ Function *DoPromotion(Function *F, std::vector<Argument*> &ArgsToPromote);
};
- RegisterOpt<ArgPromotion> X("argpromotion",
- "Promote 'by reference' arguments to scalars");
+ char ArgPromotion::ID = 0;
+ RegisterPass<ArgPromotion> X("argpromotion",
+ "Promote 'by reference' arguments to scalars");
}
Pass *llvm::createArgumentPromotionPass() {
return new ArgPromotion();
}
-bool ArgPromotion::run(Module &M) {
- bool Changed = false;
- for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I)
- if (I->hasInternalLinkage()) {
- WorkList.insert(I);
+bool ArgPromotion::runOnSCC(const std::vector<CallGraphNode *> &SCC) {
+ bool Changed = false, LocalChange;
- // If there are any constant pointer refs pointing to this function,
- // eliminate them now if possible.
- ConstantPointerRef *CPR = 0;
- for (Value::use_iterator UI = I->use_begin(), E = I->use_end(); UI != E;
- ++UI)
- if ((CPR = dyn_cast<ConstantPointerRef>(*UI)))
- break; // Found one!
- if (CPR) {
- // See if we can transform all users to use the function directly.
- while (!CPR->use_empty()) {
- User *TheUser = CPR->use_back();
- if (!isa<Constant>(TheUser) && !isa<GlobalVariable>(TheUser)) {
- Changed = true;
- TheUser->replaceUsesOfWith(CPR, I);
- } else {
- // We won't be able to eliminate all users. :(
- WorkList.erase(I); // Minor efficiency win.
- break;
- }
- }
+ do { // Iterate until we stop promoting from this SCC.
+ LocalChange = false;
+ // Attempt to promote arguments from all functions in this SCC.
+ for (unsigned i = 0, e = SCC.size(); i != e; ++i)
+ LocalChange |= PromoteArguments(SCC[i]);
+ Changed |= LocalChange; // Remember that we changed something.
+ } while (LocalChange);
- // If we nuked all users of the CPR, kill the CPR now!
- if (CPR->use_empty()) {
- CPR->destroyConstant();
- Changed = true;
- }
- }
- }
-
- while (!WorkList.empty()) {
- Function *F = *WorkList.begin();
- WorkList.erase(WorkList.begin());
-
- if (PromoteArguments(F)) // Attempt to promote an argument.
- Changed = true; // Remember that we changed something.
- }
-
return Changed;
}
+/// PromoteArguments - This method checks the specified function to see if there
+/// are any promotable arguments and if it is safe to promote the function (for
+/// example, all callers are direct). If safe to promote some arguments, it
+/// calls the DoPromotion method.
+///
+bool ArgPromotion::PromoteArguments(CallGraphNode *CGN) {
+ Function *F = CGN->getFunction();
-bool ArgPromotion::PromoteArguments(Function *F) {
- assert(F->hasInternalLinkage() && "We can only process internal functions!");
+ // Make sure that it is local to this module.
+ 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::aiterator I = F->abegin(), E = F->aend(); I != E; ++I)
+ for (Function::arg_iterator I = F->arg_begin(), E = F->arg_end(); I != E; ++I)
if (isa<PointerType>(I->getType()))
PointerArgs.push_back(I);
if (PointerArgs.empty()) return false;
for (Value::use_iterator UI = F->use_begin(), E = F->use_end();
UI != E; ++UI) {
CallSite CS = CallSite::get(*UI);
- if (Instruction *I = CS.getInstruction()) {
- // 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!
- } else {
- return false; // Cannot promote an indirect call!
- }
+ if (!CS.getInstruction()) // "Taking the address" of the function
+ return false;
+
+ // 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!
}
// Check to see which arguments are promotable. If an argument is not
if (PointerArgs.empty()) return false;
// Okay, promote all of the arguments are rewrite the callees!
- DoPromotion(F, PointerArgs);
+ Function *NewF = DoPromotion(F, PointerArgs);
+
+ // Update the call graph to know that the old function is gone.
+ getAnalysis<CallGraph>().changeFunction(F, NewF);
+ return true;
+}
+
+/// IsAlwaysValidPointer - Return true if the specified pointer is always legal
+/// to load.
+static bool IsAlwaysValidPointer(Value *V) {
+ if (isa<AllocaInst>(V) || isa<GlobalVariable>(V)) return true;
+ if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(V))
+ return IsAlwaysValidPointer(GEP->getOperand(0));
+ if (ConstantExpr *CE = dyn_cast<ConstantExpr>(V))
+ if (CE->getOpcode() == Instruction::GetElementPtr)
+ return IsAlwaysValidPointer(CE->getOperand(0));
+
+ return false;
+}
+
+/// AllCalleesPassInValidPointerForArgument - Return true if we can prove that
+/// all callees pass in a valid pointer for the specified function argument.
+static bool AllCalleesPassInValidPointerForArgument(Argument *Arg) {
+ Function *Callee = Arg->getParent();
+
+ unsigned ArgNo = std::distance(Callee->arg_begin(),
+ Function::arg_iterator(Arg));
+
+ // Look at all call sites of the function. At this pointer we know we only
+ // have direct callees.
+ for (Value::use_iterator UI = Callee->use_begin(), E = Callee->use_end();
+ UI != E; ++UI) {
+ CallSite CS = CallSite::get(*UI);
+ assert(CS.getInstruction() && "Should only have direct calls!");
+
+ if (!IsAlwaysValidPointer(CS.getArgument(ArgNo)))
+ return false;
+ }
return true;
}
+
+/// isSafeToPromoteArgument - As you might guess from the name of this method,
+/// it checks to see if it is both safe and useful to promote the argument.
+/// 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 {
// 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;
+ BasicBlock *EntryBlock = Arg->getParent()->begin();
std::vector<LoadInst*> Loads;
- std::vector<std::vector<Constant*> > GEPIndices;
+ std::vector<std::vector<ConstantInt*> > 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;
} 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);
}
// Ensure that all of the indices are constants.
- std::vector<Constant*> Operands;
+ std::vector<ConstantInt*> Operands;
for (unsigned i = 1, e = GEP->getNumOperands(); i != e; ++i)
- if (Constant *C = dyn_cast<Constant>(GEP->getOperand(i)))
+ if (ConstantInt *C = dyn_cast<ConstantInt>(GEP->getOperand(i)))
Operands.push_back(C);
else
return false; // Not a constant operand GEP!
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;
} else {
return false;
}
- // See if there is already a GEP with these indices. If so, check to make
- // sure that we aren't promoting too many elements. If not, nothing to
- // do.
+ // See if there is already a GEP with these indices. If not, check to
+ // make sure that we aren't promoting too many elements. If so, nothing
+ // to do.
if (std::find(GEPIndices.begin(), GEPIndices.end(), Operands) ==
GEPIndices.end()) {
if (GEPIndices.size() == 3) {
+ DOUT << "argpromotion disable promoting argument '"
+ << Arg->getName() << "' because it would require adding more "
+ << "than 3 arguments to the function.\n";
// We limit aggregate promotion to only promoting up to three elements
// of the aggregate.
return false;
return false; // Not a load or a GEP.
}
- if (Loads.empty()) return true; // No users, dead argument.
+ if (Loads.empty()) return true; // No users, this is a dead argument.
+
+ // If we decide that we want to promote this argument, the value is going to
+ // be unconditionally loaded in all callees. This is only safe to do if the
+ // pointer was going to be unconditionally loaded anyway (i.e. there is a load
+ // 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))
+ return false; // Cannot prove that this is safe!!
- // Okay, now we know that the argument is only used by load instructions.
- // Check to see if the pointer is guaranteed to not be modified from entry of
+ // Okay, now we know that the argument is only used by load instructions and
+ // it is safe to unconditionally load the pointer. Use alias analysis to
+ // check to see if the pointer is guaranteed to not be modified from entry of
// the function to each of the load instructions.
- Function &F = *Arg->getParent();
// Because there could be several/many load instructions, remember which
// blocks we know to be transparent to the load.
const PointerType *LoadTy =
cast<PointerType>(Load->getOperand(0)->getType());
- unsigned LoadSize = TD.getTypeSize(LoadTy->getElementType());
+ unsigned LoadSize = (unsigned)TD.getTypeSize(LoadTy->getElementType());
if (AA.canInstructionRangeModify(BB->front(), *Load, Arg, LoadSize))
return false; // Pointer is invalidated!
return true;
}
+namespace {
+ /// GEPIdxComparator - Provide a strong ordering for GEP indices. All Value*
+ /// elements are instances of ConstantInt.
+ ///
+ struct GEPIdxComparator {
+ bool operator()(const std::vector<Value*> &LHS,
+ const std::vector<Value*> &RHS) const {
+ unsigned idx = 0;
+ for (; idx < LHS.size() && idx < RHS.size(); ++idx) {
+ if (LHS[idx] != RHS[idx]) {
+ return cast<ConstantInt>(LHS[idx])->getZExtValue() <
+ cast<ConstantInt>(RHS[idx])->getZExtValue();
+ }
+ }
+
+ // Return less than if we ran out of stuff in LHS and we didn't run out of
+ // stuff in RHS.
+ return idx == LHS.size() && idx != RHS.size();
+ }
+ };
+}
-void ArgPromotion::DoPromotion(Function *F, std::vector<Argument*> &Args2Prom) {
+
+/// DoPromotion - This method actually performs the promotion of the specified
+/// 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());
-
+
// Start by computing a new prototype for the function, which is the same as
// the old function, but has modified arguments.
const FunctionType *FTy = F->getFunctionType();
std::vector<const Type*> Params;
+ typedef std::set<std::vector<Value*>, GEPIdxComparator> ScalarizeTable;
+
// ScalarizedElements - If we are promoting a pointer that has elements
// accessed out of it, keep track of which elements are accessed so that we
// can add one argument for each.
// Arguments that are directly loaded will have a zero element value here, to
// handle cases where there are both a direct load and GEP accesses.
//
- std::map<Argument*, std::set<std::vector<Value*> > > ScalarizedElements;
+ std::map<Argument*, ScalarizeTable> ScalarizedElements;
+
+ // OriginalLoads - Keep track of a representative load instruction from the
+ // original function so that we can tell the alias analysis implementation
+ // what the new GEP/Load instructions we are inserting look like.
+ std::map<std::vector<Value*>, LoadInst*> OriginalLoads;
- for (Function::aiterator I = F->abegin(), E = F->aend(); I != E; ++I)
+ for (Function::arg_iterator I = F->arg_begin(), E = F->arg_end(); I != E; ++I)
if (!ArgsToPromote.count(I)) {
Params.push_back(I->getType());
- } else if (!I->use_empty()) {
+ } else if (I->use_empty()) {
+ ++NumArgumentsDead;
+ } else {
// Okay, this is being promoted. Check to see if there are any GEP uses
// of the argument.
- std::set<std::vector<Value*> > &ArgIndices = ScalarizedElements[I];
+ ScalarizeTable &ArgIndices = ScalarizedElements[I];
for (Value::use_iterator UI = I->use_begin(), E = I->use_end(); UI != E;
++UI) {
Instruction *User = cast<Instruction>(*UI);
assert(isa<LoadInst>(User) || isa<GetElementPtrInst>(User));
- ArgIndices.insert(std::vector<Value*>(User->op_begin()+1,
- User->op_end()));
+ std::vector<Value*> Indices(User->op_begin()+1, User->op_end());
+ ArgIndices.insert(Indices);
+ LoadInst *OrigLoad;
+ if (LoadInst *L = dyn_cast<LoadInst>(User))
+ OrigLoad = L;
+ else
+ OrigLoad = cast<LoadInst>(User->use_back());
+ OriginalLoads[Indices] = OrigLoad;
}
// Add a parameter to the function for each element passed in.
- for (std::set<std::vector<Value*> >::iterator SI = ArgIndices.begin(),
+ for (ScalarizeTable::iterator SI = ArgIndices.begin(),
E = ArgIndices.end(); SI != E; ++SI)
- Params.push_back(GetElementPtrInst::getIndexedType(I->getType(), *SI));
+ Params.push_back(GetElementPtrInst::getIndexedType(I->getType(),
+ &(*SI)[0],
+ SI->size()));
if (ArgIndices.size() == 1 && ArgIndices.begin()->empty())
++NumArgumentsPromoted;
else
++NumAggregatesPromoted;
- } else {
- ++NumArgumentsDead;
}
const Type *RetTy = FTy->getReturnType();
bool ExtraArgHack = false;
if (Params.empty() && FTy->isVarArg()) {
ExtraArgHack = true;
- Params.push_back(Type::IntTy);
+ Params.push_back(Type::Int32Ty);
}
FunctionType *NFTy = FunctionType::get(RetTy, Params, FTy->isVarArg());
-
+
// Create the new function body and insert it into the module...
Function *NF = new Function(NFTy, F->getLinkage(), F->getName());
+ NF->setCallingConv(F->getCallingConv());
F->getParent()->getFunctionList().insert(F, NF);
-
+
+ // Get the alias analysis information that we need to update to reflect our
+ // changes.
+ AliasAnalysis &AA = getAnalysis<AliasAnalysis>();
+
// Loop over all of the callers of the function, transforming the call sites
// to pass in the loaded pointers.
//
CallSite CS = CallSite::get(F->use_back());
Instruction *Call = CS.getInstruction();
- // Make sure the caller of this function is revisited.
- if (Call->getParent()->getParent()->hasInternalLinkage())
- WorkList.insert(Call->getParent()->getParent());
-
- // Loop over the operands, deleting dead ones...
+ // Loop over the operands, inserting GEP and loads in the caller as
+ // appropriate.
CallSite::arg_iterator AI = CS.arg_begin();
- for (Function::aiterator I = F->abegin(), E = F->aend(); I != E; ++I, ++AI)
+ for (Function::arg_iterator I = F->arg_begin(), E = F->arg_end();
+ I != E; ++I, ++AI)
if (!ArgsToPromote.count(I))
Args.push_back(*AI); // Unmodified argument
else if (!I->use_empty()) {
- // Non-dead argument.
- std::set<std::vector<Value*> > &ArgIndices = ScalarizedElements[I];
- for (std::set<std::vector<Value*> >::iterator SI = ArgIndices.begin(),
+ // Non-dead argument: insert GEPs and loads as appropriate.
+ ScalarizeTable &ArgIndices = ScalarizedElements[I];
+ for (ScalarizeTable::iterator SI = ArgIndices.begin(),
E = ArgIndices.end(); SI != E; ++SI) {
Value *V = *AI;
- if (!SI->empty())
- V = new GetElementPtrInst(V, *SI, V->getName()+".idx", Call);
-
+ LoadInst *OrigLoad = OriginalLoads[*SI];
+ if (!SI->empty()) {
+ V = new GetElementPtrInst(V, &(*SI)[0], SI->size(),
+ V->getName()+".idx", Call);
+ AA.copyValue(OrigLoad->getOperand(0), V);
+ }
Args.push_back(new LoadInst(V, V->getName()+".val", Call));
+ AA.copyValue(OrigLoad, Args.back());
}
}
if (ExtraArgHack)
- Args.push_back(Constant::getNullValue(Type::IntTy));
+ Args.push_back(Constant::getNullValue(Type::Int32Ty));
// Push any varargs arguments on the list
for (; AI != CS.arg_end(); ++AI)
Instruction *New;
if (InvokeInst *II = dyn_cast<InvokeInst>(Call)) {
New = new InvokeInst(NF, II->getNormalDest(), II->getUnwindDest(),
- Args, "", Call);
+ &Args[0], Args.size(), "", Call);
+ cast<InvokeInst>(New)->setCallingConv(CS.getCallingConv());
} else {
- New = new CallInst(NF, Args, "", Call);
+ New = new CallInst(NF, &Args[0], Args.size(), "", Call);
+ cast<CallInst>(New)->setCallingConv(CS.getCallingConv());
+ if (cast<CallInst>(Call)->isTailCall())
+ cast<CallInst>(New)->setTailCall();
}
Args.clear();
+ // Update the alias analysis implementation to know that we are replacing
+ // the old call with a new one.
+ AA.replaceWithNewValue(Call, New);
+
if (!Call->use_empty()) {
Call->replaceAllUsesWith(New);
- std::string Name = Call->getName();
- Call->setName("");
- New->setName(Name);
+ New->takeName(Call);
}
-
+
// Finally, remove the old call from the program, reducing the use-count of
// F.
Call->getParent()->getInstList().erase(Call);
// Loop over the argument list, transfering uses of the old arguments over to
// the new arguments, also transfering over the names as well.
//
- for (Function::aiterator I = F->abegin(), E = F->aend(), I2 = NF->abegin();
- I != E; ++I)
+ for (Function::arg_iterator I = F->arg_begin(), E = F->arg_end(),
+ I2 = NF->arg_begin(); I != E; ++I)
if (!ArgsToPromote.count(I)) {
// If this is an unmodified argument, move the name and users over to the
// new version.
I->replaceAllUsesWith(I2);
- I2->setName(I->getName());
+ I2->takeName(I);
+ AA.replaceWithNewValue(I, I2);
++I2;
- } else if (!I->use_empty()) {
+ } else 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.
- std::set<std::vector<Value*> > &ArgIndices = ScalarizedElements[I];
+ ScalarizeTable &ArgIndices = ScalarizedElements[I];
while (!I->use_empty()) {
if (LoadInst *LI = dyn_cast<LoadInst>(I->use_back())) {
"Load element should sort to front!");
I2->setName(I->getName()+".val");
LI->replaceAllUsesWith(I2);
+ AA.replaceWithNewValue(LI, I2);
LI->getParent()->getInstList().erase(LI);
- DEBUG(std::cerr << "*** Promoted argument '" << I->getName()
- << "' of function '" << F->getName() << "'\n");
+ 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());
- unsigned ArgNo = 0;
- Function::aiterator TheArg = I2;
- for (std::set<std::vector<Value*> >::iterator It = ArgIndices.begin();
+ 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 += "."+itostr((int64_t)CI->getRawValue());
+ NewName += "." + CI->getValue().toString(10);
else
NewName += ".x";
TheArg->setName(NewName+".val");
- DEBUG(std::cerr << "*** Promoted agg argument '" << TheArg->getName()
- << "' of function '" << F->getName() << "'\n");
+ 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);
}
}
- // If we inserted a new pointer type, it's possible that IT could be
- // promoted too. Also, increment I2 past all of the arguments for this
- // pointer.
- for (unsigned i = 0, e = ArgIndices.size(); i != e; ++i, ++I2)
- if (isa<PointerType>(I2->getType()))
- WorkList.insert(NF);
+ // 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());
+
+
+ // Tell the alias analysis that the old function is about to disappear.
+ AA.replaceWithNewValue(F, NF);
+
// Now that the old function is dead, delete it.
F->getParent()->getFunctionList().erase(F);
+ return NF;
}