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-rw-r--r--llvm/lib/Transforms/IPO/GlobalOpt.cpp142
1 files changed, 68 insertions, 74 deletions
diff --git a/llvm/lib/Transforms/IPO/GlobalOpt.cpp b/llvm/lib/Transforms/IPO/GlobalOpt.cpp
index 234d0ecc2e5..5dab9efab22 100644
--- a/llvm/lib/Transforms/IPO/GlobalOpt.cpp
+++ b/llvm/lib/Transforms/IPO/GlobalOpt.cpp
@@ -822,42 +822,32 @@ static void ConstantPropUsersOf(Value *V, LLVMContext &Context) {
/// malloc into a global, and any loads of GV as uses of the new global.
static GlobalVariable *OptimizeGlobalAddressOfMalloc(GlobalVariable *GV,
CallInst *CI,
- const Type *AllocTy,
+ BitCastInst *BCI,
Value* NElems,
LLVMContext &Context,
TargetData* TD) {
- DEBUG(errs() << "PROMOTING GLOBAL: " << *GV << " CALL = " << *CI << '\n');
+ DEBUG(errs() << "PROMOTING MALLOC GLOBAL: " << *GV
+ << " CALL = " << *CI << " BCI = " << *BCI << '\n');
const Type *IntPtrTy = TD->getIntPtrType(Context);
- // CI has either 0 or 1 bitcast uses (getMallocType() would otherwise have
- // returned NULL and we would not be here).
- BitCastInst *BCI = NULL;
- for (Value::use_iterator UI = CI->use_begin(), E = CI->use_end(); UI != E; )
- if ((BCI = dyn_cast<BitCastInst>(cast<Instruction>(*UI++))))
- break;
-
ConstantInt *NElements = cast<ConstantInt>(NElems);
if (NElements->getZExtValue() != 1) {
// If we have an array allocation, transform it to a single element
// allocation to make the code below simpler.
- Type *NewTy = ArrayType::get(AllocTy, NElements->getZExtValue());
- unsigned TypeSize = TD->getTypeAllocSize(NewTy);
- if (const StructType *ST = dyn_cast<StructType>(NewTy))
- TypeSize = TD->getStructLayout(ST)->getSizeInBytes();
- Instruction *NewCI = CallInst::CreateMalloc(CI, IntPtrTy, NewTy,
- ConstantInt::get(IntPtrTy, TypeSize));
+ Type *NewTy = ArrayType::get(getMallocAllocatedType(CI),
+ NElements->getZExtValue());
+ Value* NewM = CallInst::CreateMalloc(CI, IntPtrTy, NewTy);
+ Instruction* NewMI = cast<Instruction>(NewM);
Value* Indices[2];
Indices[0] = Indices[1] = Constant::getNullValue(IntPtrTy);
- Value *NewGEP = GetElementPtrInst::Create(NewCI, Indices, Indices + 2,
- NewCI->getName()+".el0", CI);
- Value *Cast = new BitCastInst(NewGEP, CI->getType(), "el0", CI);
- if (BCI) BCI->replaceAllUsesWith(NewGEP);
- CI->replaceAllUsesWith(Cast);
- if (BCI) BCI->eraseFromParent();
+ Value *NewGEP = GetElementPtrInst::Create(NewMI, Indices, Indices + 2,
+ NewMI->getName()+".el0", CI);
+ BCI->replaceAllUsesWith(NewGEP);
+ BCI->eraseFromParent();
CI->eraseFromParent();
- BCI = dyn_cast<BitCastInst>(NewCI);
- CI = BCI ? extractMallocCallFromBitCast(BCI) : cast<CallInst>(NewCI);
+ BCI = cast<BitCastInst>(NewMI);
+ CI = extractMallocCallFromBitCast(NewMI);
}
// Create the new global variable. The contents of the malloc'd memory is
@@ -871,9 +861,8 @@ static GlobalVariable *OptimizeGlobalAddressOfMalloc(GlobalVariable *GV,
GV,
GV->isThreadLocal());
- // Anything that used the malloc or its bitcast now uses the global directly.
- if (BCI) BCI->replaceAllUsesWith(NewGV);
- CI->replaceAllUsesWith(new BitCastInst(NewGV, CI->getType(), "newgv", CI));
+ // Anything that used the malloc now uses the global directly.
+ BCI->replaceAllUsesWith(NewGV);
Constant *RepValue = NewGV;
if (NewGV->getType() != GV->getType()->getElementType())
@@ -941,9 +930,9 @@ static GlobalVariable *OptimizeGlobalAddressOfMalloc(GlobalVariable *GV,
GV->getParent()->getGlobalList().insert(GV, InitBool);
- // Now the GV is dead, nuke it and the malloc (both CI and BCI).
+ // Now the GV is dead, nuke it and the malloc.
GV->eraseFromParent();
- if (BCI) BCI->eraseFromParent();
+ BCI->eraseFromParent();
CI->eraseFromParent();
// To further other optimizations, loop over all users of NewGV and try to
@@ -1284,10 +1273,13 @@ static void RewriteUsesOfLoadForHeapSRoA(LoadInst *Load,
/// PerformHeapAllocSRoA - CI is an allocation of an array of structures. Break
/// it up into multiple allocations of arrays of the fields.
-static GlobalVariable *PerformHeapAllocSRoA(GlobalVariable *GV, CallInst *CI,
- Value* NElems, LLVMContext &Context,
+static GlobalVariable *PerformHeapAllocSRoA(GlobalVariable *GV,
+ CallInst *CI, BitCastInst* BCI,
+ Value* NElems,
+ LLVMContext &Context,
TargetData *TD) {
- DEBUG(errs() << "SROA HEAP ALLOC: " << *GV << " MALLOC = " << *CI << '\n');
+ DEBUG(errs() << "SROA HEAP ALLOC: " << *GV << " MALLOC CALL = " << *CI
+ << " BITCAST = " << *BCI << '\n');
const Type* MAT = getMallocAllocatedType(CI);
const StructType *STy = cast<StructType>(MAT);
@@ -1295,8 +1287,8 @@ static GlobalVariable *PerformHeapAllocSRoA(GlobalVariable *GV, CallInst *CI,
// it into GV). If there are other uses, change them to be uses of
// the global to simplify later code. This also deletes the store
// into GV.
- ReplaceUsesOfMallocWithGlobal(CI, GV);
-
+ ReplaceUsesOfMallocWithGlobal(BCI, GV);
+
// Okay, at this point, there are no users of the malloc. Insert N
// new mallocs at the same place as CI, and N globals.
std::vector<Value*> FieldGlobals;
@@ -1314,16 +1306,11 @@ static GlobalVariable *PerformHeapAllocSRoA(GlobalVariable *GV, CallInst *CI,
GV->isThreadLocal());
FieldGlobals.push_back(NGV);
- unsigned TypeSize = TD->getTypeAllocSize(FieldTy);
- if (const StructType* ST = dyn_cast<StructType>(FieldTy))
- TypeSize = TD->getStructLayout(ST)->getSizeInBytes();
- const Type* IntPtrTy = TD->getIntPtrType(Context);
- Value *NMI = CallInst::CreateMalloc(CI, IntPtrTy, FieldTy,
- ConstantInt::get(IntPtrTy, TypeSize),
- NElems,
- CI->getName() + ".f" + Twine(FieldNo));
+ Value *NMI = CallInst::CreateMalloc(CI, TD->getIntPtrType(Context),
+ FieldTy, NElems,
+ BCI->getName() + ".f" + Twine(FieldNo));
FieldMallocs.push_back(NMI);
- new StoreInst(NMI, NGV, CI);
+ new StoreInst(NMI, NGV, BCI);
}
// The tricky aspect of this transformation is handling the case when malloc
@@ -1340,18 +1327,18 @@ static GlobalVariable *PerformHeapAllocSRoA(GlobalVariable *GV, CallInst *CI,
// }
Value *RunningOr = 0;
for (unsigned i = 0, e = FieldMallocs.size(); i != e; ++i) {
- Value *Cond = new ICmpInst(CI, ICmpInst::ICMP_EQ, FieldMallocs[i],
- Constant::getNullValue(FieldMallocs[i]->getType()),
- "isnull");
+ Value *Cond = new ICmpInst(BCI, ICmpInst::ICMP_EQ, FieldMallocs[i],
+ Constant::getNullValue(FieldMallocs[i]->getType()),
+ "isnull");
if (!RunningOr)
RunningOr = Cond; // First seteq
else
- RunningOr = BinaryOperator::CreateOr(RunningOr, Cond, "tmp", CI);
+ RunningOr = BinaryOperator::CreateOr(RunningOr, Cond, "tmp", BCI);
}
// Split the basic block at the old malloc.
- BasicBlock *OrigBB = CI->getParent();
- BasicBlock *ContBB = OrigBB->splitBasicBlock(CI, "malloc_cont");
+ BasicBlock *OrigBB = BCI->getParent();
+ BasicBlock *ContBB = OrigBB->splitBasicBlock(BCI, "malloc_cont");
// Create the block to check the first condition. Put all these blocks at the
// end of the function as they are unlikely to be executed.
@@ -1387,8 +1374,9 @@ static GlobalVariable *PerformHeapAllocSRoA(GlobalVariable *GV, CallInst *CI,
}
BranchInst::Create(ContBB, NullPtrBlock);
-
- // CI is no longer needed, remove it.
+
+ // CI and BCI are no longer needed, remove them.
+ BCI->eraseFromParent();
CI->eraseFromParent();
/// InsertedScalarizedLoads - As we process loads, if we can't immediately
@@ -1475,10 +1463,14 @@ static GlobalVariable *PerformHeapAllocSRoA(GlobalVariable *GV, CallInst *CI,
/// cast of malloc.
static bool TryToOptimizeStoreOfMallocToGlobal(GlobalVariable *GV,
CallInst *CI,
- const Type *AllocTy,
+ BitCastInst *BCI,
Module::global_iterator &GVI,
TargetData *TD,
LLVMContext &Context) {
+ // If we can't figure out the type being malloced, then we can't optimize.
+ const Type *AllocTy = getMallocAllocatedType(CI);
+ assert(AllocTy);
+
// If this is a malloc of an abstract type, don't touch it.
if (!AllocTy->isSized())
return false;
@@ -1499,7 +1491,7 @@ static bool TryToOptimizeStoreOfMallocToGlobal(GlobalVariable *GV,
// for.
{
SmallPtrSet<PHINode*, 8> PHIs;
- if (!ValueIsOnlyUsedLocallyOrStoredToOneGlobal(CI, GV, PHIs))
+ if (!ValueIsOnlyUsedLocallyOrStoredToOneGlobal(BCI, GV, PHIs))
return false;
}
@@ -1507,16 +1499,16 @@ static bool TryToOptimizeStoreOfMallocToGlobal(GlobalVariable *GV,
// transform the program to use global memory instead of malloc'd memory.
// This eliminates dynamic allocation, avoids an indirection accessing the
// data, and exposes the resultant global to further GlobalOpt.
+ Value *NElems = getMallocArraySize(CI, Context, TD);
// We cannot optimize the malloc if we cannot determine malloc array size.
- if (Value *NElems = getMallocArraySize(CI, Context, TD)) {
+ if (NElems) {
if (ConstantInt *NElements = dyn_cast<ConstantInt>(NElems))
// Restrict this transformation to only working on small allocations
// (2048 bytes currently), as we don't want to introduce a 16M global or
// something.
if (TD &&
NElements->getZExtValue() * TD->getTypeAllocSize(AllocTy) < 2048) {
- GVI = OptimizeGlobalAddressOfMalloc(GV, CI, AllocTy, NElems,
- Context, TD);
+ GVI = OptimizeGlobalAddressOfMalloc(GV, CI, BCI, NElems, Context, TD);
return true;
}
@@ -1534,29 +1526,26 @@ static bool TryToOptimizeStoreOfMallocToGlobal(GlobalVariable *GV,
// This the structure has an unreasonable number of fields, leave it
// alone.
if (AllocSTy->getNumElements() <= 16 && AllocSTy->getNumElements() != 0 &&
- AllGlobalLoadUsesSimpleEnoughForHeapSRA(GV, CI)) {
+ AllGlobalLoadUsesSimpleEnoughForHeapSRA(GV, BCI)) {
// If this is a fixed size array, transform the Malloc to be an alloc of
// structs. malloc [100 x struct],1 -> malloc struct, 100
if (const ArrayType *AT =
dyn_cast<ArrayType>(getMallocAllocatedType(CI))) {
- const Type *IntPtrTy = TD->getIntPtrType(Context);
- unsigned TypeSize = TD->getStructLayout(AllocSTy)->getSizeInBytes();
- Value *AllocSize = ConstantInt::get(IntPtrTy, TypeSize);
- Value *NumElements = ConstantInt::get(IntPtrTy, AT->getNumElements());
- Instruction *Malloc = CallInst::CreateMalloc(CI, IntPtrTy, AllocSTy,
- AllocSize, NumElements,
- CI->getName());
- Instruction *Cast = new BitCastInst(Malloc, CI->getType(), "tmp", CI);
- CI->replaceAllUsesWith(Cast);
+ Value* NumElements = ConstantInt::get(Type::getInt32Ty(Context),
+ AT->getNumElements());
+ Value* NewMI = CallInst::CreateMalloc(CI, TD->getIntPtrType(Context),
+ AllocSTy, NumElements,
+ BCI->getName());
+ Value *Cast = new BitCastInst(NewMI, getMallocType(CI), "tmp", CI);
+ BCI->replaceAllUsesWith(Cast);
+ BCI->eraseFromParent();
CI->eraseFromParent();
- CI = dyn_cast<BitCastInst>(Malloc) ?
- extractMallocCallFromBitCast(Malloc):
- cast<CallInst>(Malloc);
+ BCI = cast<BitCastInst>(NewMI);
+ CI = extractMallocCallFromBitCast(NewMI);
}
- GVI = PerformHeapAllocSRoA(GV, CI, getMallocArraySize(CI, Context, TD),
- Context, TD);
+ GVI = PerformHeapAllocSRoA(GV, CI, BCI, NElems, Context, TD);
return true;
}
}
@@ -1588,10 +1577,15 @@ static bool OptimizeOnceStoredGlobal(GlobalVariable *GV, Value *StoredOnceVal,
if (OptimizeAwayTrappingUsesOfLoads(GV, SOVC, Context))
return true;
} else if (CallInst *CI = extractMallocCall(StoredOnceVal)) {
- const Type* MallocType = getMallocAllocatedType(CI);
- if (MallocType && TryToOptimizeStoreOfMallocToGlobal(GV, CI, MallocType,
- GVI, TD, Context))
- return true;
+ if (getMallocAllocatedType(CI)) {
+ BitCastInst* BCI = NULL;
+ for (Value::use_iterator UI = CI->use_begin(), E = CI->use_end();
+ UI != E; )
+ BCI = dyn_cast<BitCastInst>(cast<Instruction>(*UI++));
+ if (BCI &&
+ TryToOptimizeStoreOfMallocToGlobal(GV, CI, BCI, GVI, TD, Context))
+ return true;
+ }
}
}
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