#define DEBUG_TYPE "globalopt"
#include "llvm/Transforms/IPO.h"
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/SmallPtrSet.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/Statistic.h"
+#include "llvm/Analysis/ConstantFolding.h"
+#include "llvm/Analysis/MemoryBuiltins.h"
#include "llvm/CallingConv.h"
#include "llvm/Constants.h"
+#include "llvm/DataLayout.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Instructions.h"
#include "llvm/IntrinsicInst.h"
#include "llvm/Module.h"
#include "llvm/Operator.h"
#include "llvm/Pass.h"
-#include "llvm/Analysis/ConstantFolding.h"
-#include "llvm/Analysis/MemoryBuiltins.h"
-#include "llvm/DataLayout.h"
-#include "llvm/Target/TargetLibraryInfo.h"
#include "llvm/Support/CallSite.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/GetElementPtrTypeIterator.h"
#include "llvm/Support/MathExtras.h"
#include "llvm/Support/raw_ostream.h"
-#include "llvm/ADT/DenseMap.h"
-#include "llvm/ADT/SmallPtrSet.h"
-#include "llvm/ADT/SmallVector.h"
-#include "llvm/ADT/Statistic.h"
-#include "llvm/ADT/STLExtras.h"
+#include "llvm/Target/TargetLibraryInfo.h"
#include <algorithm>
using namespace llvm;
/// an instruction (e.g. a constant expr or GV initializer).
bool HasNonInstructionUser;
- /// HasPHIUser - Set to true if this global has a user that is a PHI node.
- bool HasPHIUser;
-
/// AtomicOrdering - Set to the strongest atomic ordering requirement.
AtomicOrdering Ordering;
GlobalStatus() : isCompared(false), isLoaded(false), StoredType(NotStored),
StoredOnceValue(0), AccessingFunction(0),
HasMultipleAccessingFunctions(false),
- HasNonInstructionUser(false), HasPHIUser(false),
- Ordering(NotAtomic) {}
+ HasNonInstructionUser(false), Ordering(NotAtomic) {}
};
}
const User *U = *UI;
if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(U)) {
GS.HasNonInstructionUser = true;
-
+
// If the result of the constantexpr isn't pointer type, then we won't
// know to expect it in various places. Just reject early.
if (!isa<PointerType>(CE->getType())) return true;
-
+
if (AnalyzeGlobal(CE, GS, PHIUsers)) return true;
} else if (const Instruction *I = dyn_cast<Instruction>(U)) {
if (!GS.HasMultipleAccessingFunctions) {
// Don't hack on volatile stores.
if (SI->isVolatile()) return true;
+
GS.Ordering = StrongerOrdering(GS.Ordering, SI->getOrdering());
// If this is a direct store to the global (i.e., the global is a scalar
if (const GlobalVariable *GV = dyn_cast<GlobalVariable>(
SI->getOperand(1))) {
Value *StoredVal = SI->getOperand(0);
+
+ if (Constant *C = dyn_cast<Constant>(StoredVal)) {
+ if (C->isThreadDependent()) {
+ // The stored value changes between threads; don't track it.
+ return true;
+ }
+ }
+
if (StoredVal == GV->getInitializer()) {
if (GS.StoredType < GlobalStatus::isInitializerStored)
GS.StoredType = GlobalStatus::isInitializerStored;
// have to be careful about infinite recursion.
if (PHIUsers.insert(PN)) // Not already visited.
if (AnalyzeGlobal(I, GS, PHIUsers)) return true;
- GS.HasPHIUser = true;
} else if (isa<CmpInst>(I)) {
GS.isCompared = true;
} else if (const MemTransferInst *MTI = dyn_cast<MemTransferInst>(I)) {
}
}
-static AttrListPtr StripNest(const AttrListPtr &Attrs) {
+static AttributeSet StripNest(LLVMContext &C, const AttributeSet &Attrs) {
for (unsigned i = 0, e = Attrs.getNumSlots(); i != e; ++i) {
if (!Attrs.getSlot(i).Attrs.hasAttribute(Attributes::Nest))
continue;
// There can be only one.
- return Attrs.removeAttr(Attrs.getSlot(i).Index, Attribute::Nest);
+ return Attrs.removeAttr(C, Attrs.getSlot(i).Index,
+ Attributes::get(C, Attributes::Nest));
}
return Attrs;
}
static void RemoveNestAttribute(Function *F) {
- F->setAttributes(StripNest(F->getAttributes()));
+ F->setAttributes(StripNest(F->getContext(), F->getAttributes()));
for (Value::use_iterator UI = F->use_begin(), E = F->use_end(); UI != E;++UI){
if (isa<BlockAddress>(*UI))
continue;
CallSite User(cast<Instruction>(*UI));
- User.setAttributes(StripNest(User.getAttributes()));
+ User.setAttributes(StripNest(F->getContext(), User.getAttributes()));
}
}
Changed = true;
}
- if (F->getAttributes().hasAttrSomewhere(Attribute::Nest) &&
+ if (F->getAttributes().hasAttrSomewhere(Attributes::Nest) &&
!F->hasAddressTaken()) {
// The function is not used by a trampoline intrinsic, so it is safe
// to remove the 'nest' attribute.
GlobalVariable *GlobalOpt::FindGlobalCtors(Module &M) {
GlobalVariable *GV = M.getGlobalVariable("llvm.global_ctors");
if (GV == 0) return 0;
-
+
// Verify that the initializer is simple enough for us to handle. We are
// only allowed to optimize the initializer if it is unique.
if (!GV->hasUniqueInitializer()) return 0;
}
-static inline bool
+static inline bool
isSimpleEnoughValueToCommit(Constant *C,
SmallPtrSet<Constant*, 8> &SimpleConstants,
const DataLayout *TD);
if (C->getNumOperands() == 0 || isa<BlockAddress>(C) ||
isa<GlobalValue>(C))
return true;
-
+
// Aggregate values are safe if all their elements are.
if (isa<ConstantArray>(C) || isa<ConstantStruct>(C) ||
isa<ConstantVector>(C)) {
}
return true;
}
-
+
// We don't know exactly what relocations are allowed in constant expressions,
// so we allow &global+constantoffset, which is safe and uniformly supported
// across targets.
TD->getTypeSizeInBits(CE->getOperand(0)->getType()))
return false;
return isSimpleEnoughValueToCommit(CE->getOperand(0), SimpleConstants, TD);
-
+
// GEP is fine if it is simple + constant offset.
case Instruction::GetElementPtr:
for (unsigned i = 1, e = CE->getNumOperands(); i != e; ++i)
if (!isa<ConstantInt>(CE->getOperand(i)))
return false;
return isSimpleEnoughValueToCommit(CE->getOperand(0), SimpleConstants, TD);
-
+
case Instruction::Add:
// We allow simple+cst.
if (!isa<ConstantInt>(CE->getOperand(1)))
return false;
}
-static inline bool
+static inline bool
isSimpleEnoughValueToCommit(Constant *C,
SmallPtrSet<Constant*, 8> &SimpleConstants,
const DataLayout *TD) {
return false;
return ConstantFoldLoadThroughGEPConstantExpr(GV->getInitializer(), CE);
-
+
// A constantexpr bitcast from a pointer to another pointer is a no-op,
// and we know how to evaluate it by moving the bitcast from the pointer
// operand to the value operand.
return cast<GlobalVariable>(CE->getOperand(0))->hasUniqueInitializer();
}
}
-
+
return false;
}
// Return the modified struct.
return ConstantStruct::get(STy, Elts);
}
-
+
ConstantInt *CI = cast<ConstantInt>(Addr->getOperand(OpNo));
SequentialType *InitTy = cast<SequentialType>(Init->getType());
if (!isSimpleEnoughPointerToCommit(Ptr))
// If this is too complex for us to commit, reject it.
return false;
-
+
Constant *Val = getVal(SI->getOperand(0));
// If this might be too difficult for the backend to handle (e.g. the addr
// of one global variable divided by another) then we can't commit it.
if (!isSimpleEnoughValueToCommit(Val, SimpleConstants, TD))
return false;
-
+
if (ConstantExpr *CE = dyn_cast<ConstantExpr>(Ptr))
if (CE->getOpcode() == Instruction::BitCast) {
// If we're evaluating a store through a bitcast, then we need
// to pull the bitcast off the pointer type and push it onto the
// stored value.
Ptr = CE->getOperand(0);
-
+
Type *NewTy = cast<PointerType>(Ptr->getType())->getElementType();
-
+
// In order to push the bitcast onto the stored value, a bitcast
// from NewTy to Val's type must be legal. If it's not, we can try
// introspecting NewTy to find a legal conversion.
return false;
}
}
-
+
// If we found compatible types, go ahead and push the bitcast
// onto the stored value.
Val = ConstantExpr::getBitCast(Val, NewTy);
}
-
+
MutatedMemory[Ptr] = Val;
} else if (BinaryOperator *BO = dyn_cast<BinaryOperator>(CurInst)) {
InstResult = ConstantExpr::get(BO->getOpcode(),
if (!CurInst->use_empty()) {
if (ConstantExpr *CE = dyn_cast<ConstantExpr>(InstResult))
InstResult = ConstantFoldConstantExpression(CE, TD, TLI);
-
+
setVal(CurInst, InstResult);
}
Constant *RetValDummy;
bool EvalSuccess = Eval.EvaluateFunction(F, RetValDummy,
SmallVector<Constant*, 0>());
-
+
if (EvalSuccess) {
// We succeeded at evaluation: commit the result.
DEBUG(dbgs() << "FULLY EVALUATED GLOBAL CTOR FUNCTION '"
return 0;
Function *Fn = M.getFunction(TLI->getName(LibFunc::cxa_atexit));
-
+
if (!Fn)
return 0;
FunctionType *FTy = Fn->getFunctionType();
-
- // Checking that the function has the right return type, the right number of
+
+ // Checking that the function has the right return type, the right number of
// parameters and that they all have pointer types should be enough.
if (!FTy->getReturnType()->isIntegerTy() ||
FTy->getNumParams() != 3 ||
// and remove them.
bool Changed = false;
- for (Function::use_iterator I = CXAAtExitFn->use_begin(),
+ for (Function::use_iterator I = CXAAtExitFn->use_begin(),
E = CXAAtExitFn->use_end(); I != E;) {
// We're only interested in calls. Theoretically, we could handle invoke
// instructions as well, but neither llvm-gcc nor clang generate invokes
if (!CI)
continue;
- Function *DtorFn =
+ Function *DtorFn =
dyn_cast<Function>(CI->getArgOperand(0)->stripPointerCasts());
if (!DtorFn)
continue;