//===----------------------------------------------------------------------===//
#include "TransformInternals.h"
-#include "llvm/Method.h"
#include "llvm/Type.h"
-#include "llvm/ConstantVals.h"
#include "llvm/Analysis/Expressions.h"
+#include "llvm/Function.h"
#include "llvm/iOther.h"
+#include <algorithm>
// TargetData Hack: Eventually we will have annotations given to us by the
// backend so that we know stuff about type size and alignments. For now
"ReplaceInstWithInst: Instruction already inserted into basic block!");
// Insert the new instruction into the basic block...
- BI = BIL.insert(BI, I)+1;
+ BI = BIL.insert(BI, I)+1; // Increment BI to point to instruction to delete
// Replace all uses of the old instruction, and delete it.
ReplaceInstWithValue(BIL, BI, I);
- // Reexamine the instruction just inserted next time around the cleanup pass
- // loop.
+ // Move BI back to point to the newly inserted instruction
--BI;
}
+void ReplaceInstWithInst(Instruction *From, Instruction *To) {
+ BasicBlock *BB = From->getParent();
+ BasicBlock::InstListType &BIL = BB->getInstList();
+ BasicBlock::iterator BI = find(BIL.begin(), BIL.end(), From);
+ assert(BI != BIL.end() && "Inst not in it's parents BB!");
+ ReplaceInstWithInst(BIL, BI, To);
+}
+
+// InsertInstBeforeInst - Insert 'NewInst' into the basic block that 'Existing'
+// is already in, and put it right before 'Existing'. This instruction should
+// only be used when there is no iterator to Existing already around. The
+// returned iterator points to the new instruction.
+//
+BasicBlock::iterator InsertInstBeforeInst(Instruction *NewInst,
+ Instruction *Existing) {
+ BasicBlock *BB = Existing->getParent();
+ BasicBlock::InstListType &BIL = BB->getInstList();
+ BasicBlock::iterator BI = find(BIL.begin(), BIL.end(), Existing);
+ assert(BI != BIL.end() && "Inst not in it's parents BB!");
+ return BIL.insert(BI, NewInst);
+}
+
+
+
+static const Type *getStructOffsetStep(const StructType *STy, unsigned &Offset,
+ std::vector<Value*> &Indices) {
+ assert(Offset < TD.getTypeSize(STy) && "Offset not in composite!");
+ const StructLayout *SL = TD.getStructLayout(STy);
+
+ // This loop terminates always on a 0 <= i < MemberOffsets.size()
+ unsigned i;
+ for (i = 0; i < SL->MemberOffsets.size()-1; ++i)
+ if (Offset >= SL->MemberOffsets[i] && Offset < SL->MemberOffsets[i+1])
+ break;
+
+ assert(Offset >= SL->MemberOffsets[i] &&
+ (i == SL->MemberOffsets.size()-1 || Offset < SL->MemberOffsets[i+1]));
+
+ // Make sure to save the current index...
+ Indices.push_back(ConstantUInt::get(Type::UByteTy, i));
+ Offset = SL->MemberOffsets[i];
+ return STy->getContainedType(i);
+}
+
// getStructOffsetType - Return a vector of offsets that are to be used to index
// into the specified struct type to get as close as possible to index as we
// false if you want a leaf
//
const Type *getStructOffsetType(const Type *Ty, unsigned &Offset,
- vector<Value*> &Offsets,
+ std::vector<Value*> &Indices,
bool StopEarly = true) {
- if (!isa<CompositeType>(Ty) ||
- (Offset == 0 && StopEarly && !Offsets.empty())) {
- Offset = 0; // Return the offset that we were able to acheive
+ if (Offset == 0 && StopEarly && !Indices.empty())
return Ty; // Return the leaf type
- }
unsigned ThisOffset;
const Type *NextType;
if (const StructType *STy = dyn_cast<StructType>(Ty)) {
- assert(Offset < TD.getTypeSize(Ty) && "Offset not in composite!");
- const StructLayout *SL = TD.getStructLayout(STy);
-
- // This loop terminates always on a 0 <= i < MemberOffsets.size()
- unsigned i;
- for (i = 0; i < SL->MemberOffsets.size()-1; ++i)
- if (Offset >= SL->MemberOffsets[i] && Offset < SL->MemberOffsets[i+1])
- break;
-
- assert(Offset >= SL->MemberOffsets[i] &&
- (i == SL->MemberOffsets.size()-1 || Offset <SL->MemberOffsets[i+1]));
-
- // Make sure to save the current index...
- Offsets.push_back(ConstantUInt::get(Type::UByteTy, i));
- ThisOffset = SL->MemberOffsets[i];
- NextType = STy->getElementTypes()[i];
- } else {
- const ArrayType *ATy = cast<ArrayType>(Ty);
- assert(ATy->isUnsized() || Offset < TD.getTypeSize(Ty) &&
- "Offset not in composite!");
+ ThisOffset = Offset;
+ NextType = getStructOffsetStep(STy, ThisOffset, Indices);
+ } else if (const ArrayType *ATy = dyn_cast<ArrayType>(Ty)) {
+ assert(Offset < TD.getTypeSize(ATy) && "Offset not in composite!");
NextType = ATy->getElementType();
unsigned ChildSize = TD.getTypeSize(NextType);
- Offsets.push_back(ConstantUInt::get(Type::UIntTy, Offset/ChildSize));
+ Indices.push_back(ConstantUInt::get(Type::UIntTy, Offset/ChildSize));
ThisOffset = (Offset/ChildSize)*ChildSize;
+ } else {
+ Offset = 0; // Return the offset that we were able to acheive
+ return Ty; // Return the leaf type
}
unsigned SubOffs = Offset - ThisOffset;
- const Type *LeafTy = getStructOffsetType(NextType, SubOffs, Offsets);
+ const Type *LeafTy = getStructOffsetType(NextType, SubOffs,
+ Indices, StopEarly);
Offset = ThisOffset + SubOffs;
return LeafTy;
}
// instruction. The type returned is the root type that the GEP would point to
//
const Type *ConvertableToGEP(const Type *Ty, Value *OffsetVal,
- vector<Value*> &Indices,
+ std::vector<Value*> &Indices,
BasicBlock::iterator *BI = 0) {
- const CompositeType *CompTy = getPointedToComposite(Ty);
+ const CompositeType *CompTy = dyn_cast<CompositeType>(Ty);
if (CompTy == 0) return 0;
// See if the cast is of an integer expression that is either a constant,
//
analysis::ExprType Expr = analysis::ClassifyExpression(OffsetVal);
- // The expression must either be a constant, or a scaled index to be useful
- if (!Expr.Offset && !Expr.Scale)
- return 0;
-
- // Get the offset and scale now...
- unsigned Offset = 0, Scale = Expr.Var != 0;
-
- // Get the offset value if it exists...
- if (Expr.Offset) {
- int Val = getConstantValue(Expr.Offset);
- if (Val < 0) return false; // Don't mess with negative offsets
- Offset = (unsigned)Val;
- }
-
- // Get the scale value if it exists...
- if (Expr.Scale) {
- int Val = getConstantValue(Expr.Scale);
- if (Val < 0) return false; // Don't mess with negative scales
- Scale = (unsigned)Val;
- }
-
- // Check to make sure the offset is not negative or really large, outside the
- // scope of this structure...
+ // Get the offset and scale values if they exists...
+ // A scale of zero with Expr.Var != 0 means a scale of 1.
//
- if (!isa<ArrayType>(CompTy) || cast<ArrayType>(CompTy)->isSized())
- if (Offset >= TD.getTypeSize(CompTy))
- return 0;
+ int Offset = Expr.Offset ? getConstantValue(Expr.Offset) : 0;
+ int Scale = Expr.Scale ? getConstantValue(Expr.Scale) : 0;
+ if (Expr.Var && Scale == 0) Scale = 1; // Scale != 0 if Expr.Var != 0
+
// Loop over the Scale and Offset values, filling in the Indices vector for
// our final getelementptr instruction.
//
CompTy = cast<CompositeType>(NextTy);
if (const StructType *StructTy = dyn_cast<StructType>(CompTy)) {
- const StructLayout *SL = TD.getStructLayout(StructTy);
- unsigned ActualOffset = Offset;
- NextTy = getStructOffsetType(StructTy, ActualOffset, Indices);
+ // Step into the appropriate element of the structure...
+ unsigned ActualOffset = (Offset < 0) ? 0 : (unsigned)Offset;
+ NextTy = getStructOffsetStep(StructTy, ActualOffset, Indices);
Offset -= ActualOffset;
} else {
- const ArrayType *AT = cast<ArrayType>(CompTy);
- const Type *ElTy = AT->getElementType();
+ const Type *ElTy = cast<SequentialType>(CompTy)->getElementType();
+ if (!ElTy->isSized())
+ return 0; // Type is unreasonable... escape!
unsigned ElSize = TD.getTypeSize(ElTy);
+ int ElSizeS = (int)ElSize;
// See if the user is indexing into a different cell of this array...
- if (Scale && Scale >= ElSize) {
+ if (Scale && (Scale >= ElSizeS || -Scale >= ElSizeS)) {
// A scale n*ElSize might occur if we are not stepping through
// array by one. In this case, we will have to insert math to munge
// the index.
//
- unsigned ScaleAmt = Scale/ElSize;
- if (Scale-ScaleAmt*ElSize)
+ int ScaleAmt = Scale/ElSizeS;
+ if (Scale-ScaleAmt*ElSizeS)
return 0; // Didn't scale by a multiple of element size, bail out
- Scale = ElSize;
+ Scale = 0; // Scale is consumed
- unsigned Index = Offset/ElSize; // is zero unless Offset > ElSize
+ int Index = Offset/ElSize; // is zero unless Offset > ElSize
Offset -= Index*ElSize; // Consume part of the offset
if (BI) { // Generate code?
if (ScaleAmt && ScaleAmt != 1) {
// If we have to scale up our index, do so now
- Value *ScaleAmtVal = ConstantUInt::get(Type::UIntTy, ScaleAmt);
+ Value *ScaleAmtVal = ConstantUInt::get(Type::UIntTy,
+ (unsigned)ScaleAmt);
Instruction *Scaler = BinaryOperator::create(Instruction::Mul,
- Expr.Var,ScaleAmtVal);
+ Expr.Var, ScaleAmtVal);
if (Expr.Var->hasName())
Scaler->setName(Expr.Var->getName()+"-scale");
}
if (Index) { // Add an offset to the index
- Value *IndexAmt = ConstantUInt::get(Type::UIntTy, Index);
+ Value *IndexAmt = ConstantUInt::get(Type::UIntTy, (unsigned)Index);
Instruction *Offseter = BinaryOperator::create(Instruction::Add,
Expr.Var, IndexAmt);
if (Expr.Var->hasName())
}
Indices.push_back(Expr.Var);
- Scale = 0; // Consume scale factor!
- } else if (Offset >= ElSize) {
+ Expr.Var = 0;
+ } else if (Offset >= (int)ElSize || -Offset >= (int)ElSize) {
// Calculate the index that we are entering into the array cell with
unsigned Index = Offset/ElSize;
Indices.push_back(ConstantUInt::get(Type::UIntTy, Index));
- Offset -= Index*ElSize; // Consume part of the offset
+ Offset -= (int)(Index*ElSize); // Consume part of the offset
- } else {
+ } else if (isa<ArrayType>(CompTy) || Indices.empty()) {
// Must be indexing a small amount into the first cell of the array
// Just index into element zero of the array here.
//
Indices.push_back(ConstantUInt::get(Type::UIntTy, 0));
+ } else {
+ return 0; // Hrm. wierd, can't handle this case. Bail
}
NextTy = ElTy;
}