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Move sparc specific code into the Sparc backend

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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@5317 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2003-01-15 21:36:50 +00:00
parent ac4dfd0643
commit 795ba6cabd
6 changed files with 275 additions and 558 deletions
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44
include/llvm/CodeGen/InstrSelectionSupport.h
View File

@ -14,50 +14,6 @@ class InstructionNode;
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
//

256
lib/CodeGen/InstrSelection/InstrSelectionSupport.cpp
View File

@ -7,18 +7,15 @@
#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 ******************************/
@ -51,257 +48,6 @@ InsertCodeToLoadConstant(Function *F,
}
//---------------------------------------------------------------------------
// 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,

256
lib/Target/SparcV9/InstrSelection/InstrSelectionSupport.cpp
View File

@ -7,18 +7,15 @@
#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 ******************************/
@ -51,257 +48,6 @@ InsertCodeToLoadConstant(Function *F,
}
//---------------------------------------------------------------------------
// 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,

47
lib/Target/SparcV9/SparcV9InstrInfo.cpp
View File

@ -20,6 +20,53 @@ static const uint32_t MAXLO = (1 << 10) - 1; // set bits set by %lo(*)
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
//

224
lib/Target/SparcV9/SparcV9InstrSelection.cpp
View File

@ -35,6 +35,227 @@ static inline void Add3OperandInstr(unsigned Opcode, InstructionNode* Node,
//---------------------------------------------------------------------------
// 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 ******************************/
@ -964,8 +1185,7 @@ SetOperandsForMemInstr(unsigned Opcode,
// 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");

2
lib/Target/SparcV9/SparcV9Internals.h
View File

@ -742,4 +742,6 @@ public:
Pass* getEmitBytecodeToAsmPass(std::ostream &Out);
};
int64_t GetConstantValueAsSignedInt(const Value *V, bool &isValidConstant);
#endif