class TargetMachine;
class Instruction;
-//---------------------------------------------------------------------------
-// Function GetConstantValueAsUnsignedInt
-// Function GetConstantValueAsSignedInt
-//
-// Convenience functions to get the value of an integer constant, for an
-// appropriate integer or non-integer type that can be held in a signed
-// or unsigned integer respectively. The type of the argument must be
-// the following:
-// Signed or unsigned integer
-// Boolean
-// Pointer
-//
-// isValidConstant is set to true if a valid constant was found.
-//---------------------------------------------------------------------------
-
-uint64_t GetConstantValueAsUnsignedInt (const Value *V,
- bool &isValidConstant);
-
-int64_t GetConstantValueAsSignedInt (const Value *V,
- bool &isValidConstant);
-
-
-//---------------------------------------------------------------------------
-// Function: GetMemInstArgs
-//
-// Purpose:
-// Get the pointer value and the index vector for a memory operation
-// (GetElementPtr, Load, or Store). If all indices of the given memory
-// operation are constant, fold in constant indices in a chain of
-// preceding GetElementPtr instructions (if any), and return the
-// pointer value of the first instruction in the chain.
-// All folded instructions are marked so no code is generated for them.
-//
-// Return values:
-// Returns the pointer Value to use.
-// Returns the resulting IndexVector in idxVec.
-// Returns true/false in allConstantIndices if all indices are/aren't const.
-//---------------------------------------------------------------------------
-
-Value* GetMemInstArgs (InstructionNode* memInstrNode,
- std::vector<Value*>& idxVec,
- bool& allConstantIndices);
-
-
//---------------------------------------------------------------------------
// Function: ChooseRegOrImmed
//
#include "llvm/CodeGen/InstrSelectionSupport.h"
#include "llvm/CodeGen/InstrSelection.h"
-#include "llvm/CodeGen/MachineInstr.h"
#include "llvm/CodeGen/MachineInstrAnnot.h"
#include "llvm/CodeGen/MachineCodeForInstruction.h"
-#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/InstrForest.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/TargetRegInfo.h"
#include "llvm/Target/TargetInstrInfo.h"
#include "llvm/Constants.h"
-#include "llvm/Function.h"
+#include "llvm/BasicBlock.h"
#include "llvm/DerivedTypes.h"
-#include "llvm/iMemory.h"
using std::vector;
//*************************** Local Functions ******************************/
}
-//---------------------------------------------------------------------------
-// Function GetConstantValueAsUnsignedInt
-// Function GetConstantValueAsSignedInt
-//
-// Convenience functions to get the value of an integral constant, for an
-// appropriate integer or non-integer type that can be held in a signed
-// or unsigned integer respectively. The type of the argument must be
-// the following:
-// Signed or unsigned integer
-// Boolean
-// Pointer
-//
-// isValidConstant is set to true if a valid constant was found.
-//---------------------------------------------------------------------------
-
-uint64_t
-GetConstantValueAsUnsignedInt(const Value *V,
- bool &isValidConstant)
-{
- isValidConstant = true;
-
- if (isa<Constant>(V))
- if (const ConstantBool *CB = dyn_cast<ConstantBool>(V))
- return (int64_t)CB->getValue();
- else if (const ConstantSInt *CS = dyn_cast<ConstantSInt>(V))
- return (uint64_t)CS->getValue();
- else if (const ConstantUInt *CU = dyn_cast<ConstantUInt>(V))
- return CU->getValue();
-
- isValidConstant = false;
- return 0;
-}
-
-int64_t
-GetConstantValueAsSignedInt(const Value *V,
- bool &isValidConstant)
-{
- uint64_t C = GetConstantValueAsUnsignedInt(V, isValidConstant);
- if (isValidConstant) {
- if (V->getType()->isSigned() || C < INT64_MAX) // safe to cast to signed
- return (int64_t) C;
- else
- isValidConstant = false;
- }
- return 0;
-}
-
-
-//---------------------------------------------------------------------------
-// Function: FoldGetElemChain
-//
-// Purpose:
-// Fold a chain of GetElementPtr instructions containing only
-// constant offsets into an equivalent (Pointer, IndexVector) pair.
-// Returns the pointer Value, and stores the resulting IndexVector
-// in argument chainIdxVec. This is a helper function for
-// FoldConstantIndices that does the actual folding.
-//---------------------------------------------------------------------------
-
-
-// Check for a constant 0.
-inline bool
-IsZero(Value* idx)
-{
- return (idx == ConstantSInt::getNullValue(idx->getType()));
-}
-
-static Value*
-FoldGetElemChain(InstrTreeNode* ptrNode, vector<Value*>& chainIdxVec,
- bool lastInstHasLeadingNonZero)
-{
- InstructionNode* gepNode = dyn_cast<InstructionNode>(ptrNode);
- GetElementPtrInst* gepInst =
- dyn_cast_or_null<GetElementPtrInst>(gepNode ? gepNode->getInstruction() :0);
-
- // ptr value is not computed in this tree or ptr value does not come from GEP
- // instruction
- if (gepInst == NULL)
- return NULL;
-
- // Return NULL if we don't fold any instructions in.
- Value* ptrVal = NULL;
-
- // Now chase the chain of getElementInstr instructions, if any.
- // Check for any non-constant indices and stop there.
- // Also, stop if the first index of child is a non-zero array index
- // and the last index of the current node is a non-array index:
- // in that case, a non-array declared type is being accessed as an array
- // which is not type-safe, but could be legal.
- //
- InstructionNode* ptrChild = gepNode;
- while (ptrChild && (ptrChild->getOpLabel() == Instruction::GetElementPtr ||
- ptrChild->getOpLabel() == GetElemPtrIdx))
- {
- // Child is a GetElemPtr instruction
- gepInst = cast<GetElementPtrInst>(ptrChild->getValue());
- User::op_iterator OI, firstIdx = gepInst->idx_begin();
- User::op_iterator lastIdx = gepInst->idx_end();
- bool allConstantOffsets = true;
-
- // The first index of every GEP must be an array index.
- assert((*firstIdx)->getType() == Type::LongTy &&
- "INTERNAL ERROR: Structure index for a pointer type!");
-
- // If the last instruction had a leading non-zero index, check if the
- // current one references a sequential (i.e., indexable) type.
- // If not, the code is not type-safe and we would create an illegal GEP
- // by folding them, so don't fold any more instructions.
- //
- if (lastInstHasLeadingNonZero)
- if (! isa<SequentialType>(gepInst->getType()->getElementType()))
- break; // cannot fold in any preceding getElementPtr instrs.
-
- // Check that all offsets are constant for this instruction
- for (OI = firstIdx; allConstantOffsets && OI != lastIdx; ++OI)
- allConstantOffsets = isa<ConstantInt>(*OI);
-
- if (allConstantOffsets)
- { // Get pointer value out of ptrChild.
- ptrVal = gepInst->getPointerOperand();
-
- // Remember if it has leading zero index: it will be discarded later.
- lastInstHasLeadingNonZero = ! IsZero(*firstIdx);
-
- // Insert its index vector at the start, skipping any leading [0]
- chainIdxVec.insert(chainIdxVec.begin(),
- firstIdx + !lastInstHasLeadingNonZero, lastIdx);
-
- // Mark the folded node so no code is generated for it.
- ((InstructionNode*) ptrChild)->markFoldedIntoParent();
-
- // Get the previous GEP instruction and continue trying to fold
- ptrChild = dyn_cast<InstructionNode>(ptrChild->leftChild());
- }
- else // cannot fold this getElementPtr instr. or any preceding ones
- break;
- }
-
- // If the first getElementPtr instruction had a leading [0], add it back.
- // Note that this instruction is the *last* one successfully folded above.
- if (ptrVal && ! lastInstHasLeadingNonZero)
- chainIdxVec.insert(chainIdxVec.begin(), ConstantSInt::get(Type::LongTy,0));
-
- return ptrVal;
-}
-
-
-//---------------------------------------------------------------------------
-// Function: GetGEPInstArgs
-//
-// Purpose:
-// Helper function for GetMemInstArgs that handles the final getElementPtr
-// instruction used by (or same as) the memory operation.
-// Extracts the indices of the current instruction and tries to fold in
-// preceding ones if all indices of the current one are constant.
-//---------------------------------------------------------------------------
-
-Value*
-GetGEPInstArgs(InstructionNode* gepNode,
- vector<Value*>& idxVec,
- bool& allConstantIndices)
-{
- allConstantIndices = true;
- GetElementPtrInst* gepI = cast<GetElementPtrInst>(gepNode->getInstruction());
-
- // Default pointer is the one from the current instruction.
- Value* ptrVal = gepI->getPointerOperand();
- InstrTreeNode* ptrChild = gepNode->leftChild();
-
- // Extract the index vector of the GEP instructin.
- // If all indices are constant and first index is zero, try to fold
- // in preceding GEPs with all constant indices.
- for (User::op_iterator OI=gepI->idx_begin(), OE=gepI->idx_end();
- allConstantIndices && OI != OE; ++OI)
- if (! isa<Constant>(*OI))
- allConstantIndices = false; // note: this also terminates loop!
-
- // If we have only constant indices, fold chains of constant indices
- // in this and any preceding GetElemPtr instructions.
- bool foldedGEPs = false;
- bool leadingNonZeroIdx = gepI && ! IsZero(*gepI->idx_begin());
- if (allConstantIndices)
- if (Value* newPtr = FoldGetElemChain(ptrChild, idxVec, leadingNonZeroIdx))
- {
- ptrVal = newPtr;
- foldedGEPs = true;
- }
-
- // Append the index vector of the current instruction.
- // Skip the leading [0] index if preceding GEPs were folded into this.
- idxVec.insert(idxVec.end(),
- gepI->idx_begin() + (foldedGEPs && !leadingNonZeroIdx),
- gepI->idx_end());
-
- return ptrVal;
-}
-
-//---------------------------------------------------------------------------
-// Function: GetMemInstArgs
-//
-// Purpose:
-// Get the pointer value and the index vector for a memory operation
-// (GetElementPtr, Load, or Store). If all indices of the given memory
-// operation are constant, fold in constant indices in a chain of
-// preceding GetElementPtr instructions (if any), and return the
-// pointer value of the first instruction in the chain.
-// All folded instructions are marked so no code is generated for them.
-//
-// Return values:
-// Returns the pointer Value to use.
-// Returns the resulting IndexVector in idxVec.
-// Returns true/false in allConstantIndices if all indices are/aren't const.
-//---------------------------------------------------------------------------
-
-Value*
-GetMemInstArgs(InstructionNode* memInstrNode,
- vector<Value*>& idxVec,
- bool& allConstantIndices)
-{
- allConstantIndices = false;
- Instruction* memInst = memInstrNode->getInstruction();
- assert(idxVec.size() == 0 && "Need empty vector to return indices");
-
- // If there is a GetElemPtr instruction to fold in to this instr,
- // it must be in the left child for Load and GetElemPtr, and in the
- // right child for Store instructions.
- InstrTreeNode* ptrChild = (memInst->getOpcode() == Instruction::Store
- ? memInstrNode->rightChild()
- : memInstrNode->leftChild());
-
- // Default pointer is the one from the current instruction.
- Value* ptrVal = ptrChild->getValue();
-
- // Find the "last" GetElemPtr instruction: this one or the immediate child.
- // There will be none if this is a load or a store from a scalar pointer.
- InstructionNode* gepNode = NULL;
- if (isa<GetElementPtrInst>(memInst))
- gepNode = memInstrNode;
- else if (isa<InstructionNode>(ptrChild) && isa<GetElementPtrInst>(ptrVal))
- { // Child of load/store is a GEP and memInst is its only use.
- // Use its indices and mark it as folded.
- gepNode = cast<InstructionNode>(ptrChild);
- gepNode->markFoldedIntoParent();
- }
-
- // If there are no indices, return the current pointer.
- // Else extract the pointer from the GEP and fold the indices.
- return gepNode ? GetGEPInstArgs(gepNode, idxVec, allConstantIndices)
- : ptrVal;
-}
-
MachineOperand::MachineOperandType
ChooseRegOrImmed(int64_t intValue,
bool isSigned,
getImmedValue = 0;
if (canUseImmed &&
- target.getInstrInfo().constantFitsInImmedField(opCode, intValue))
+ target.getInstrInfo().constantFitsInImmedField(opCode, intValue))
{
opType = isSigned? MachineOperand::MO_SignExtendedImmed
: MachineOperand::MO_UnextendedImmed;
#include "llvm/CodeGen/InstrSelectionSupport.h"
#include "llvm/CodeGen/InstrSelection.h"
-#include "llvm/CodeGen/MachineInstr.h"
#include "llvm/CodeGen/MachineInstrAnnot.h"
#include "llvm/CodeGen/MachineCodeForInstruction.h"
-#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/InstrForest.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/TargetRegInfo.h"
#include "llvm/Target/TargetInstrInfo.h"
#include "llvm/Constants.h"
-#include "llvm/Function.h"
+#include "llvm/BasicBlock.h"
#include "llvm/DerivedTypes.h"
-#include "llvm/iMemory.h"
using std::vector;
//*************************** Local Functions ******************************/
}
-//---------------------------------------------------------------------------
-// Function GetConstantValueAsUnsignedInt
-// Function GetConstantValueAsSignedInt
-//
-// Convenience functions to get the value of an integral constant, for an
-// appropriate integer or non-integer type that can be held in a signed
-// or unsigned integer respectively. The type of the argument must be
-// the following:
-// Signed or unsigned integer
-// Boolean
-// Pointer
-//
-// isValidConstant is set to true if a valid constant was found.
-//---------------------------------------------------------------------------
-
-uint64_t
-GetConstantValueAsUnsignedInt(const Value *V,
- bool &isValidConstant)
-{
- isValidConstant = true;
-
- if (isa<Constant>(V))
- if (const ConstantBool *CB = dyn_cast<ConstantBool>(V))
- return (int64_t)CB->getValue();
- else if (const ConstantSInt *CS = dyn_cast<ConstantSInt>(V))
- return (uint64_t)CS->getValue();
- else if (const ConstantUInt *CU = dyn_cast<ConstantUInt>(V))
- return CU->getValue();
-
- isValidConstant = false;
- return 0;
-}
-
-int64_t
-GetConstantValueAsSignedInt(const Value *V,
- bool &isValidConstant)
-{
- uint64_t C = GetConstantValueAsUnsignedInt(V, isValidConstant);
- if (isValidConstant) {
- if (V->getType()->isSigned() || C < INT64_MAX) // safe to cast to signed
- return (int64_t) C;
- else
- isValidConstant = false;
- }
- return 0;
-}
-
-
-//---------------------------------------------------------------------------
-// Function: FoldGetElemChain
-//
-// Purpose:
-// Fold a chain of GetElementPtr instructions containing only
-// constant offsets into an equivalent (Pointer, IndexVector) pair.
-// Returns the pointer Value, and stores the resulting IndexVector
-// in argument chainIdxVec. This is a helper function for
-// FoldConstantIndices that does the actual folding.
-//---------------------------------------------------------------------------
-
-
-// Check for a constant 0.
-inline bool
-IsZero(Value* idx)
-{
- return (idx == ConstantSInt::getNullValue(idx->getType()));
-}
-
-static Value*
-FoldGetElemChain(InstrTreeNode* ptrNode, vector<Value*>& chainIdxVec,
- bool lastInstHasLeadingNonZero)
-{
- InstructionNode* gepNode = dyn_cast<InstructionNode>(ptrNode);
- GetElementPtrInst* gepInst =
- dyn_cast_or_null<GetElementPtrInst>(gepNode ? gepNode->getInstruction() :0);
-
- // ptr value is not computed in this tree or ptr value does not come from GEP
- // instruction
- if (gepInst == NULL)
- return NULL;
-
- // Return NULL if we don't fold any instructions in.
- Value* ptrVal = NULL;
-
- // Now chase the chain of getElementInstr instructions, if any.
- // Check for any non-constant indices and stop there.
- // Also, stop if the first index of child is a non-zero array index
- // and the last index of the current node is a non-array index:
- // in that case, a non-array declared type is being accessed as an array
- // which is not type-safe, but could be legal.
- //
- InstructionNode* ptrChild = gepNode;
- while (ptrChild && (ptrChild->getOpLabel() == Instruction::GetElementPtr ||
- ptrChild->getOpLabel() == GetElemPtrIdx))
- {
- // Child is a GetElemPtr instruction
- gepInst = cast<GetElementPtrInst>(ptrChild->getValue());
- User::op_iterator OI, firstIdx = gepInst->idx_begin();
- User::op_iterator lastIdx = gepInst->idx_end();
- bool allConstantOffsets = true;
-
- // The first index of every GEP must be an array index.
- assert((*firstIdx)->getType() == Type::LongTy &&
- "INTERNAL ERROR: Structure index for a pointer type!");
-
- // If the last instruction had a leading non-zero index, check if the
- // current one references a sequential (i.e., indexable) type.
- // If not, the code is not type-safe and we would create an illegal GEP
- // by folding them, so don't fold any more instructions.
- //
- if (lastInstHasLeadingNonZero)
- if (! isa<SequentialType>(gepInst->getType()->getElementType()))
- break; // cannot fold in any preceding getElementPtr instrs.
-
- // Check that all offsets are constant for this instruction
- for (OI = firstIdx; allConstantOffsets && OI != lastIdx; ++OI)
- allConstantOffsets = isa<ConstantInt>(*OI);
-
- if (allConstantOffsets)
- { // Get pointer value out of ptrChild.
- ptrVal = gepInst->getPointerOperand();
-
- // Remember if it has leading zero index: it will be discarded later.
- lastInstHasLeadingNonZero = ! IsZero(*firstIdx);
-
- // Insert its index vector at the start, skipping any leading [0]
- chainIdxVec.insert(chainIdxVec.begin(),
- firstIdx + !lastInstHasLeadingNonZero, lastIdx);
-
- // Mark the folded node so no code is generated for it.
- ((InstructionNode*) ptrChild)->markFoldedIntoParent();
-
- // Get the previous GEP instruction and continue trying to fold
- ptrChild = dyn_cast<InstructionNode>(ptrChild->leftChild());
- }
- else // cannot fold this getElementPtr instr. or any preceding ones
- break;
- }
-
- // If the first getElementPtr instruction had a leading [0], add it back.
- // Note that this instruction is the *last* one successfully folded above.
- if (ptrVal && ! lastInstHasLeadingNonZero)
- chainIdxVec.insert(chainIdxVec.begin(), ConstantSInt::get(Type::LongTy,0));
-
- return ptrVal;
-}
-
-
-//---------------------------------------------------------------------------
-// Function: GetGEPInstArgs
-//
-// Purpose:
-// Helper function for GetMemInstArgs that handles the final getElementPtr
-// instruction used by (or same as) the memory operation.
-// Extracts the indices of the current instruction and tries to fold in
-// preceding ones if all indices of the current one are constant.
-//---------------------------------------------------------------------------
-
-Value*
-GetGEPInstArgs(InstructionNode* gepNode,
- vector<Value*>& idxVec,
- bool& allConstantIndices)
-{
- allConstantIndices = true;
- GetElementPtrInst* gepI = cast<GetElementPtrInst>(gepNode->getInstruction());
-
- // Default pointer is the one from the current instruction.
- Value* ptrVal = gepI->getPointerOperand();
- InstrTreeNode* ptrChild = gepNode->leftChild();
-
- // Extract the index vector of the GEP instructin.
- // If all indices are constant and first index is zero, try to fold
- // in preceding GEPs with all constant indices.
- for (User::op_iterator OI=gepI->idx_begin(), OE=gepI->idx_end();
- allConstantIndices && OI != OE; ++OI)
- if (! isa<Constant>(*OI))
- allConstantIndices = false; // note: this also terminates loop!
-
- // If we have only constant indices, fold chains of constant indices
- // in this and any preceding GetElemPtr instructions.
- bool foldedGEPs = false;
- bool leadingNonZeroIdx = gepI && ! IsZero(*gepI->idx_begin());
- if (allConstantIndices)
- if (Value* newPtr = FoldGetElemChain(ptrChild, idxVec, leadingNonZeroIdx))
- {
- ptrVal = newPtr;
- foldedGEPs = true;
- }
-
- // Append the index vector of the current instruction.
- // Skip the leading [0] index if preceding GEPs were folded into this.
- idxVec.insert(idxVec.end(),
- gepI->idx_begin() + (foldedGEPs && !leadingNonZeroIdx),
- gepI->idx_end());
-
- return ptrVal;
-}
-
-//---------------------------------------------------------------------------
-// Function: GetMemInstArgs
-//
-// Purpose:
-// Get the pointer value and the index vector for a memory operation
-// (GetElementPtr, Load, or Store). If all indices of the given memory
-// operation are constant, fold in constant indices in a chain of
-// preceding GetElementPtr instructions (if any), and return the
-// pointer value of the first instruction in the chain.
-// All folded instructions are marked so no code is generated for them.
-//
-// Return values:
-// Returns the pointer Value to use.
-// Returns the resulting IndexVector in idxVec.
-// Returns true/false in allConstantIndices if all indices are/aren't const.
-//---------------------------------------------------------------------------
-
-Value*
-GetMemInstArgs(InstructionNode* memInstrNode,
- vector<Value*>& idxVec,
- bool& allConstantIndices)
-{
- allConstantIndices = false;
- Instruction* memInst = memInstrNode->getInstruction();
- assert(idxVec.size() == 0 && "Need empty vector to return indices");
-
- // If there is a GetElemPtr instruction to fold in to this instr,
- // it must be in the left child for Load and GetElemPtr, and in the
- // right child for Store instructions.
- InstrTreeNode* ptrChild = (memInst->getOpcode() == Instruction::Store
- ? memInstrNode->rightChild()
- : memInstrNode->leftChild());
-
- // Default pointer is the one from the current instruction.
- Value* ptrVal = ptrChild->getValue();
-
- // Find the "last" GetElemPtr instruction: this one or the immediate child.
- // There will be none if this is a load or a store from a scalar pointer.
- InstructionNode* gepNode = NULL;
- if (isa<GetElementPtrInst>(memInst))
- gepNode = memInstrNode;
- else if (isa<InstructionNode>(ptrChild) && isa<GetElementPtrInst>(ptrVal))
- { // Child of load/store is a GEP and memInst is its only use.
- // Use its indices and mark it as folded.
- gepNode = cast<InstructionNode>(ptrChild);
- gepNode->markFoldedIntoParent();
- }
-
- // If there are no indices, return the current pointer.
- // Else extract the pointer from the GEP and fold the indices.
- return gepNode ? GetGEPInstArgs(gepNode, idxVec, allConstantIndices)
- : ptrVal;
-}
-
MachineOperand::MachineOperandType
ChooseRegOrImmed(int64_t intValue,
bool isSigned,
getImmedValue = 0;
if (canUseImmed &&
- target.getInstrInfo().constantFitsInImmedField(opCode, intValue))
+ target.getInstrInfo().constantFitsInImmedField(opCode, intValue))
{
opType = isSigned? MachineOperand::MO_SignExtendedImmed
: MachineOperand::MO_UnextendedImmed;
static const uint32_t MAXSIMM = (1 << 12) - 1; // set bits in simm13 field of OR
+//---------------------------------------------------------------------------
+// Function GetConstantValueAsUnsignedInt
+// Function GetConstantValueAsSignedInt
+//
+// Convenience functions to get the value of an integral constant, for an
+// appropriate integer or non-integer type that can be held in a signed
+// or unsigned integer respectively. The type of the argument must be
+// the following:
+// Signed or unsigned integer
+// Boolean
+// Pointer
+//
+// isValidConstant is set to true if a valid constant was found.
+//---------------------------------------------------------------------------
+
+static uint64_t
+GetConstantValueAsUnsignedInt(const Value *V,
+ bool &isValidConstant)
+{
+ isValidConstant = true;
+
+ if (isa<Constant>(V))
+ if (const ConstantBool *CB = dyn_cast<ConstantBool>(V))
+ return (int64_t)CB->getValue();
+ else if (const ConstantSInt *CS = dyn_cast<ConstantSInt>(V))
+ return (uint64_t)CS->getValue();
+ else if (const ConstantUInt *CU = dyn_cast<ConstantUInt>(V))
+ return CU->getValue();
+
+ isValidConstant = false;
+ return 0;
+}
+
+int64_t
+GetConstantValueAsSignedInt(const Value *V, bool &isValidConstant)
+{
+ uint64_t C = GetConstantValueAsUnsignedInt(V, isValidConstant);
+ if (isValidConstant) {
+ if (V->getType()->isSigned() || C < INT64_MAX) // safe to cast to signed
+ return (int64_t) C;
+ else
+ isValidConstant = false;
+ }
+ return 0;
+}
+
+
//----------------------------------------------------------------------------
// Function: CreateSETUWConst
//
+//---------------------------------------------------------------------------
+// Function: GetMemInstArgs
+//
+// Purpose:
+// Get the pointer value and the index vector for a memory operation
+// (GetElementPtr, Load, or Store). If all indices of the given memory
+// operation are constant, fold in constant indices in a chain of
+// preceding GetElementPtr instructions (if any), and return the
+// pointer value of the first instruction in the chain.
+// All folded instructions are marked so no code is generated for them.
+//
+// Return values:
+// Returns the pointer Value to use.
+// Returns the resulting IndexVector in idxVec.
+// Returns true/false in allConstantIndices if all indices are/aren't const.
+//---------------------------------------------------------------------------
+
+
+//---------------------------------------------------------------------------
+// Function: FoldGetElemChain
+//
+// Purpose:
+// Fold a chain of GetElementPtr instructions containing only
+// constant offsets into an equivalent (Pointer, IndexVector) pair.
+// Returns the pointer Value, and stores the resulting IndexVector
+// in argument chainIdxVec. This is a helper function for
+// FoldConstantIndices that does the actual folding.
+//---------------------------------------------------------------------------
+
+
+// Check for a constant 0.
+inline bool
+IsZero(Value* idx)
+{
+ return (idx == ConstantSInt::getNullValue(idx->getType()));
+}
+
+static Value*
+FoldGetElemChain(InstrTreeNode* ptrNode, vector<Value*>& chainIdxVec,
+ bool lastInstHasLeadingNonZero)
+{
+ InstructionNode* gepNode = dyn_cast<InstructionNode>(ptrNode);
+ GetElementPtrInst* gepInst =
+ dyn_cast_or_null<GetElementPtrInst>(gepNode ? gepNode->getInstruction() :0);
+
+ // ptr value is not computed in this tree or ptr value does not come from GEP
+ // instruction
+ if (gepInst == NULL)
+ return NULL;
+
+ // Return NULL if we don't fold any instructions in.
+ Value* ptrVal = NULL;
+
+ // Now chase the chain of getElementInstr instructions, if any.
+ // Check for any non-constant indices and stop there.
+ // Also, stop if the first index of child is a non-zero array index
+ // and the last index of the current node is a non-array index:
+ // in that case, a non-array declared type is being accessed as an array
+ // which is not type-safe, but could be legal.
+ //
+ InstructionNode* ptrChild = gepNode;
+ while (ptrChild && (ptrChild->getOpLabel() == Instruction::GetElementPtr ||
+ ptrChild->getOpLabel() == GetElemPtrIdx))
+ {
+ // Child is a GetElemPtr instruction
+ gepInst = cast<GetElementPtrInst>(ptrChild->getValue());
+ User::op_iterator OI, firstIdx = gepInst->idx_begin();
+ User::op_iterator lastIdx = gepInst->idx_end();
+ bool allConstantOffsets = true;
+
+ // The first index of every GEP must be an array index.
+ assert((*firstIdx)->getType() == Type::LongTy &&
+ "INTERNAL ERROR: Structure index for a pointer type!");
+
+ // If the last instruction had a leading non-zero index, check if the
+ // current one references a sequential (i.e., indexable) type.
+ // If not, the code is not type-safe and we would create an illegal GEP
+ // by folding them, so don't fold any more instructions.
+ //
+ if (lastInstHasLeadingNonZero)
+ if (! isa<SequentialType>(gepInst->getType()->getElementType()))
+ break; // cannot fold in any preceding getElementPtr instrs.
+
+ // Check that all offsets are constant for this instruction
+ for (OI = firstIdx; allConstantOffsets && OI != lastIdx; ++OI)
+ allConstantOffsets = isa<ConstantInt>(*OI);
+
+ if (allConstantOffsets)
+ { // Get pointer value out of ptrChild.
+ ptrVal = gepInst->getPointerOperand();
+
+ // Remember if it has leading zero index: it will be discarded later.
+ lastInstHasLeadingNonZero = ! IsZero(*firstIdx);
+
+ // Insert its index vector at the start, skipping any leading [0]
+ chainIdxVec.insert(chainIdxVec.begin(),
+ firstIdx + !lastInstHasLeadingNonZero, lastIdx);
+
+ // Mark the folded node so no code is generated for it.
+ ((InstructionNode*) ptrChild)->markFoldedIntoParent();
+
+ // Get the previous GEP instruction and continue trying to fold
+ ptrChild = dyn_cast<InstructionNode>(ptrChild->leftChild());
+ }
+ else // cannot fold this getElementPtr instr. or any preceding ones
+ break;
+ }
+
+ // If the first getElementPtr instruction had a leading [0], add it back.
+ // Note that this instruction is the *last* one successfully folded above.
+ if (ptrVal && ! lastInstHasLeadingNonZero)
+ chainIdxVec.insert(chainIdxVec.begin(), ConstantSInt::get(Type::LongTy,0));
+
+ return ptrVal;
+}
+
+
+//---------------------------------------------------------------------------
+// Function: GetGEPInstArgs
+//
+// Purpose:
+// Helper function for GetMemInstArgs that handles the final getElementPtr
+// instruction used by (or same as) the memory operation.
+// Extracts the indices of the current instruction and tries to fold in
+// preceding ones if all indices of the current one are constant.
+//---------------------------------------------------------------------------
+
+static Value *
+GetGEPInstArgs(InstructionNode* gepNode,
+ vector<Value*>& idxVec,
+ bool& allConstantIndices)
+{
+ allConstantIndices = true;
+ GetElementPtrInst* gepI = cast<GetElementPtrInst>(gepNode->getInstruction());
+
+ // Default pointer is the one from the current instruction.
+ Value* ptrVal = gepI->getPointerOperand();
+ InstrTreeNode* ptrChild = gepNode->leftChild();
+
+ // Extract the index vector of the GEP instructin.
+ // If all indices are constant and first index is zero, try to fold
+ // in preceding GEPs with all constant indices.
+ for (User::op_iterator OI=gepI->idx_begin(), OE=gepI->idx_end();
+ allConstantIndices && OI != OE; ++OI)
+ if (! isa<Constant>(*OI))
+ allConstantIndices = false; // note: this also terminates loop!
+
+ // If we have only constant indices, fold chains of constant indices
+ // in this and any preceding GetElemPtr instructions.
+ bool foldedGEPs = false;
+ bool leadingNonZeroIdx = gepI && ! IsZero(*gepI->idx_begin());
+ if (allConstantIndices)
+ if (Value* newPtr = FoldGetElemChain(ptrChild, idxVec, leadingNonZeroIdx))
+ {
+ ptrVal = newPtr;
+ foldedGEPs = true;
+ }
+
+ // Append the index vector of the current instruction.
+ // Skip the leading [0] index if preceding GEPs were folded into this.
+ idxVec.insert(idxVec.end(),
+ gepI->idx_begin() + (foldedGEPs && !leadingNonZeroIdx),
+ gepI->idx_end());
+
+ return ptrVal;
+}
+
+//---------------------------------------------------------------------------
+// Function: GetMemInstArgs
+//
+// Purpose:
+// Get the pointer value and the index vector for a memory operation
+// (GetElementPtr, Load, or Store). If all indices of the given memory
+// operation are constant, fold in constant indices in a chain of
+// preceding GetElementPtr instructions (if any), and return the
+// pointer value of the first instruction in the chain.
+// All folded instructions are marked so no code is generated for them.
+//
+// Return values:
+// Returns the pointer Value to use.
+// Returns the resulting IndexVector in idxVec.
+// Returns true/false in allConstantIndices if all indices are/aren't const.
+//---------------------------------------------------------------------------
+
+static Value*
+GetMemInstArgs(InstructionNode* memInstrNode,
+ vector<Value*>& idxVec,
+ bool& allConstantIndices)
+{
+ allConstantIndices = false;
+ Instruction* memInst = memInstrNode->getInstruction();
+ assert(idxVec.size() == 0 && "Need empty vector to return indices");
+
+ // If there is a GetElemPtr instruction to fold in to this instr,
+ // it must be in the left child for Load and GetElemPtr, and in the
+ // right child for Store instructions.
+ InstrTreeNode* ptrChild = (memInst->getOpcode() == Instruction::Store
+ ? memInstrNode->rightChild()
+ : memInstrNode->leftChild());
+
+ // Default pointer is the one from the current instruction.
+ Value* ptrVal = ptrChild->getValue();
+
+ // Find the "last" GetElemPtr instruction: this one or the immediate child.
+ // There will be none if this is a load or a store from a scalar pointer.
+ InstructionNode* gepNode = NULL;
+ if (isa<GetElementPtrInst>(memInst))
+ gepNode = memInstrNode;
+ else if (isa<InstructionNode>(ptrChild) && isa<GetElementPtrInst>(ptrVal))
+ { // Child of load/store is a GEP and memInst is its only use.
+ // Use its indices and mark it as folded.
+ gepNode = cast<InstructionNode>(ptrChild);
+ gepNode->markFoldedIntoParent();
+ }
+
+ // If there are no indices, return the current pointer.
+ // Else extract the pointer from the GEP and fold the indices.
+ return gepNode ? GetGEPInstArgs(gepNode, idxVec, allConstantIndices)
+ : ptrVal;
+}
+
//************************ Internal Functions ******************************/
// offset. (An extra leading zero offset, if any, can be ignored.)
// Generate code sequence to compute address from index.
//
- bool firstIdxIsZero =
- (idxVec[0] == Constant::getNullValue(idxVec[0]->getType()));
+ bool firstIdxIsZero = IsZero(idxVec[0]);
assert(idxVec.size() == 1U + firstIdxIsZero
&& "Array refs must be lowered before Instruction Selection");
Pass* getEmitBytecodeToAsmPass(std::ostream &Out);
};
+int64_t GetConstantValueAsSignedInt(const Value *V, bool &isValidConstant);
+
#endif
projects / oota-llvm.git / commitdiff