Revert (52748 and friends):

Move GetConstantStringInfo to lib/Analysis. Remove
string output routine from Constant. Update all
callers. Change debug intrinsic api slightly to
accomodate move of routine, these now return values
instead of strings.

This unbreaks llvm-gcc bootstrap.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52884 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Anton Korobeynikov 2008-06-29 17:57:03 +00:00
parent 28a2b54580
commit 6d116bc7ce
11 changed files with 158 additions and 141 deletions

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@ -72,16 +72,7 @@ namespace llvm {
Instruction *InsertBefore = 0) {
const unsigned Idxs[1] = { Idx };
return FindInsertedValue(V, &Idxs[0], &Idxs[1], InsertBefore);
}
/// GetConstantStringInfo - This function computes the length of a
/// null-terminated C string pointed to by V. If successful, it returns true
/// and returns the string in Str. If unsuccessful, it returns false. If
/// StopAtNul is set to true (the default), the returned string is truncated
/// by a nul character in the global. If StopAtNul is false, the nul
/// character is included in the result string.
bool GetConstantStringInfo(Value *V, std::string &Str, uint64_t Offset = 0,
bool StopAtNul = true);
}
} // end namespace llvm
#endif

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@ -115,6 +115,13 @@ public:
"implemented for all constants that have operands!");
assert(0 && "Constants that do not have operands cannot be using 'From'!");
}
/// getStringValue - Turn an LLVM constant pointer that eventually points to a
/// global into a string value. Return an empty string if we can't do it.
/// Parameter Chop determines if the result is chopped at the first null
/// terminator.
///
std::string getStringValue(bool Chop = true, unsigned Offset = 0);
};
} // End llvm namespace

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@ -96,8 +96,8 @@ namespace llvm {
return unsigned(cast<ConstantInt>(getOperand(2))->getZExtValue());
}
Value* getFileName() const;
Value* getDirectory() const;
std::string getFileName() const;
std::string getDirectory() const;
// Methods for support type inquiry through isa, cast, and dyn_cast:
static inline bool classof(const DbgStopPointInst *) { return true; }

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@ -15,7 +15,6 @@
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/Constants.h"
#include "llvm/Instructions.h"
#include "llvm/GlobalVariable.h"
#include "llvm/IntrinsicInst.h"
#include "llvm/Target/TargetData.h"
#include "llvm/Support/GetElementPtrTypeIterator.h"
@ -931,102 +930,3 @@ Value *llvm::FindInsertedValue(Value *V, const unsigned *idx_begin,
// or load instruction)
return 0;
}
/// GetConstantStringInfo - This function computes the length of a
/// null-terminated C string pointed to by V. If successful, it returns true
/// and returns the string in Str. If unsuccessful, it returns false.
bool llvm::GetConstantStringInfo(Value *V, std::string &Str, uint64_t Offset,
bool StopAtNul) {
// If V is NULL then return false;
if (V == NULL) return false;
// Look through bitcast instructions.
if (BitCastInst *BCI = dyn_cast<BitCastInst>(V))
return GetConstantStringInfo(BCI->getOperand(0), Str, Offset, StopAtNul);
// If the value is not a GEP instruction nor a constant expression with a
// GEP instruction, then return false because ConstantArray can't occur
// any other way
User *GEP = 0;
if (GetElementPtrInst *GEPI = dyn_cast<GetElementPtrInst>(V)) {
GEP = GEPI;
} else if (ConstantExpr *CE = dyn_cast<ConstantExpr>(V)) {
if (CE->getOpcode() == Instruction::BitCast)
return GetConstantStringInfo(CE->getOperand(0), Str, Offset, StopAtNul);
if (CE->getOpcode() != Instruction::GetElementPtr)
return false;
GEP = CE;
}
if (GEP) {
// Make sure the GEP has exactly three arguments.
if (GEP->getNumOperands() != 3)
return false;
// Make sure the index-ee is a pointer to array of i8.
const PointerType *PT = cast<PointerType>(GEP->getOperand(0)->getType());
const ArrayType *AT = dyn_cast<ArrayType>(PT->getElementType());
if (AT == 0 || AT->getElementType() != Type::Int8Ty)
return false;
// Check to make sure that the first operand of the GEP is an integer and
// has value 0 so that we are sure we're indexing into the initializer.
ConstantInt *FirstIdx = dyn_cast<ConstantInt>(GEP->getOperand(1));
if (FirstIdx == 0 || !FirstIdx->isZero())
return false;
// If the second index isn't a ConstantInt, then this is a variable index
// into the array. If this occurs, we can't say anything meaningful about
// the string.
uint64_t StartIdx = 0;
if (ConstantInt *CI = dyn_cast<ConstantInt>(GEP->getOperand(2)))
StartIdx = CI->getZExtValue();
else
return false;
return GetConstantStringInfo(GEP->getOperand(0), Str, StartIdx+Offset,
StopAtNul);
}
// The GEP instruction, constant or instruction, must reference a global
// variable that is a constant and is initialized. The referenced constant
// initializer is the array that we'll use for optimization.
GlobalVariable* GV = dyn_cast<GlobalVariable>(V);
if (!GV || !GV->isConstant() || !GV->hasInitializer())
return false;
Constant *GlobalInit = GV->getInitializer();
// Handle the ConstantAggregateZero case
if (isa<ConstantAggregateZero>(GlobalInit)) {
// This is a degenerate case. The initializer is constant zero so the
// length of the string must be zero.
Str.clear();
return true;
}
// Must be a Constant Array
ConstantArray *Array = dyn_cast<ConstantArray>(GlobalInit);
if (Array == 0 || Array->getType()->getElementType() != Type::Int8Ty)
return false;
// Get the number of elements in the array
uint64_t NumElts = Array->getType()->getNumElements();
if (Offset > NumElts)
return false;
// Traverse the constant array from 'Offset' which is the place the GEP refers
// to in the array.
Str.reserve(NumElts-Offset);
for (unsigned i = Offset; i != NumElts; ++i) {
Constant *Elt = Array->getOperand(i);
ConstantInt *CI = dyn_cast<ConstantInt>(Elt);
if (!CI) // This array isn't suitable, non-int initializer.
return false;
if (StopAtNul && CI->isZero())
return true; // we found end of string, success!
Str += (char)CI->getZExtValue();
}
// The array isn't null terminated, but maybe this is a memcpy, not a strcpy.
return true;
}

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@ -10,7 +10,6 @@
#include "llvm/CodeGen/MachineModuleInfo.h"
#include "llvm/Constants.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineLocation.h"
@ -207,9 +206,7 @@ public:
}
virtual void Apply(std::string &Field) {
Constant *C = CI->getOperand(I++);
// Fills in the string if it succeeds
if (!GetConstantStringInfo(C, Field))
Field.clear();
Field = C->getStringValue();
}
virtual void Apply(DebugInfoDesc *&Field) {
Constant *C = CI->getOperand(I++);

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@ -12,7 +12,6 @@
//===----------------------------------------------------------------------===//
#include "llvm/CodeGen/SelectionDAG.h"
#include "llvm/Constants.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/GlobalAlias.h"
#include "llvm/GlobalVariable.h"
#include "llvm/Intrinsics.h"
@ -2578,7 +2577,8 @@ static SDOperand getMemBasePlusOffset(SDOperand Base, unsigned Offset,
/// isMemSrcFromString - Returns true if memcpy source is a string constant.
///
static bool isMemSrcFromString(SDOperand Src, std::string &Str) {
static bool isMemSrcFromString(SDOperand Src, std::string &Str,
uint64_t &SrcOff) {
unsigned SrcDelta = 0;
GlobalAddressSDNode *G = NULL;
if (Src.getOpcode() == ISD::GlobalAddress)
@ -2593,8 +2593,13 @@ static bool isMemSrcFromString(SDOperand Src, std::string &Str) {
return false;
GlobalVariable *GV = dyn_cast<GlobalVariable>(G->getGlobal());
if (GV && GetConstantStringInfo(GV, Str, SrcDelta, false))
return true;
if (GV && GV->isConstant()) {
Str = GV->getStringValue(false);
if (!Str.empty()) {
SrcOff += SrcDelta;
return true;
}
}
return false;
}
@ -2611,7 +2616,8 @@ bool MeetsMaxMemopRequirement(std::vector<MVT> &MemOps,
bool AllowUnalign = TLI.allowsUnalignedMemoryAccesses();
std::string Str;
bool isSrcStr = isMemSrcFromString(Src, Str);
uint64_t SrcOff = 0;
bool isSrcStr = isMemSrcFromString(Src, Str, SrcOff);
bool isSrcConst = isa<ConstantSDNode>(Src);
MVT VT= TLI.getOptimalMemOpType(Size, Align, isSrcConst, isSrcStr);
if (VT != MVT::iAny) {
@ -2706,11 +2712,11 @@ static SDOperand getMemcpyLoadsAndStores(SelectionDAG &DAG,
return SDOperand();
std::string Str;
bool CopyFromStr = isMemSrcFromString(Src, Str);
uint64_t SrcOff = 0, DstOff = 0;
bool CopyFromStr = isMemSrcFromString(Src, Str, SrcOff);
SmallVector<SDOperand, 8> OutChains;
unsigned NumMemOps = MemOps.size();
uint64_t SrcOff = 0, DstOff = 0;
for (unsigned i = 0; i < NumMemOps; i++) {
MVT VT = MemOps[i];
unsigned VTSize = VT.getSizeInBits() / 8;

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@ -14,7 +14,6 @@
#include "llvm/Debugger/ProgramInfo.h"
#include "llvm/Constants.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Intrinsics.h"
#include "llvm/IntrinsicInst.h"
@ -116,10 +115,8 @@ SourceFileInfo::SourceFileInfo(const GlobalVariable *Desc,
if (ConstantInt *CUI = dyn_cast<ConstantInt>(CS->getOperand(1)))
Version = CUI->getZExtValue();
if (!GetConstantStringInfo(CS->getOperand(3), BaseName))
BaseName = "";
if (!GetConstantStringInfo(CS->getOperand(4), Directory))
Directory = "";
BaseName = CS->getOperand(3)->getStringValue();
Directory = CS->getOperand(4)->getStringValue();
}
}
@ -159,8 +156,7 @@ SourceFunctionInfo::SourceFunctionInfo(ProgramInfo &PI,
SourceFile = &PI.getSourceFile(GV);
// Entry #2 is the function name.
if (!GetConstantStringInfo(CS->getOperand(2), Name))
Name = "";
Name = CS->getOperand(2)->getStringValue();
}
}

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@ -9973,8 +9973,8 @@ static Instruction *InstCombineLoadCast(InstCombiner &IC, LoadInst &LI,
if (ConstantExpr *CE = dyn_cast<ConstantExpr>(CI)) {
// Instead of loading constant c string, use corresponding integer value
// directly if string length is small enough.
std::string Str;
if (GetConstantStringInfo(CE->getOperand(0), Str) && !Str.empty()) {
const std::string &Str = CE->getOperand(0)->getStringValue();
if (!Str.empty()) {
unsigned len = Str.length();
const Type *Ty = cast<PointerType>(CE->getType())->getElementType();
unsigned numBits = Ty->getPrimitiveSizeInBits();

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@ -23,7 +23,6 @@
#include "llvm/Module.h"
#include "llvm/Pass.h"
#include "llvm/Support/IRBuilder.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/Target/TargetData.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/StringMap.h"
@ -230,6 +229,88 @@ void LibCallOptimization::EmitFWrite(Value *Ptr, Value *Size, Value *File,
// Helper Functions
//===----------------------------------------------------------------------===//
/// GetConstantStringInfo - This function computes the length of a
/// null-terminated C string pointed to by V. If successful, it returns true
/// and returns the string in Str. If unsuccessful, it returns false.
static bool GetConstantStringInfo(Value *V, std::string &Str) {
// Look bitcast instructions.
if (BitCastInst *BCI = dyn_cast<BitCastInst>(V))
return GetConstantStringInfo(BCI->getOperand(0), Str);
// If the value is not a GEP instruction nor a constant expression with a
// GEP instruction, then return false because ConstantArray can't occur
// any other way
User *GEP = 0;
if (GetElementPtrInst *GEPI = dyn_cast<GetElementPtrInst>(V)) {
GEP = GEPI;
} else if (ConstantExpr *CE = dyn_cast<ConstantExpr>(V)) {
if (CE->getOpcode() != Instruction::GetElementPtr)
return false;
GEP = CE;
} else {
return false;
}
// Make sure the GEP has exactly three arguments.
if (GEP->getNumOperands() != 3)
return false;
// Check to make sure that the first operand of the GEP is an integer and
// has value 0 so that we are sure we're indexing into the initializer.
if (ConstantInt *Idx = dyn_cast<ConstantInt>(GEP->getOperand(1))) {
if (!Idx->isZero())
return false;
} else
return false;
// If the second index isn't a ConstantInt, then this is a variable index
// into the array. If this occurs, we can't say anything meaningful about
// the string.
uint64_t StartIdx = 0;
if (ConstantInt *CI = dyn_cast<ConstantInt>(GEP->getOperand(2)))
StartIdx = CI->getZExtValue();
else
return false;
// The GEP instruction, constant or instruction, must reference a global
// variable that is a constant and is initialized. The referenced constant
// initializer is the array that we'll use for optimization.
GlobalVariable* GV = dyn_cast<GlobalVariable>(GEP->getOperand(0));
if (!GV || !GV->isConstant() || !GV->hasInitializer())
return false;
Constant *GlobalInit = GV->getInitializer();
// Handle the ConstantAggregateZero case
if (isa<ConstantAggregateZero>(GlobalInit)) {
// This is a degenerate case. The initializer is constant zero so the
// length of the string must be zero.
Str.clear();
return true;
}
// Must be a Constant Array
ConstantArray *Array = dyn_cast<ConstantArray>(GlobalInit);
if (Array == 0 || Array->getType()->getElementType() != Type::Int8Ty)
return false;
// Get the number of elements in the array
uint64_t NumElts = Array->getType()->getNumElements();
// Traverse the constant array from StartIdx (derived above) which is
// the place the GEP refers to in the array.
for (unsigned i = StartIdx; i < NumElts; ++i) {
Constant *Elt = Array->getOperand(i);
ConstantInt *CI = dyn_cast<ConstantInt>(Elt);
if (!CI) // This array isn't suitable, non-int initializer.
return false;
if (CI->isZero())
return true; // we found end of string, success!
Str += (char)CI->getZExtValue();
}
return false; // The array isn't null terminated.
}
/// GetStringLengthH - If we can compute the length of the string pointed to by
/// the specified pointer, return 'len+1'. If we can't, return 0.
static uint64_t GetStringLengthH(Value *V, SmallPtrSet<PHINode*, 32> &PHIs) {

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@ -2658,4 +2658,44 @@ void ConstantExpr::replaceUsesOfWithOnConstant(Value *From, Value *ToV,
// Delete the old constant!
destroyConstant();
}
}
/// getStringValue - Turn an LLVM constant pointer that eventually points to a
/// global into a string value. Return an empty string if we can't do it.
/// Parameter Chop determines if the result is chopped at the first null
/// terminator.
///
std::string Constant::getStringValue(bool Chop, unsigned Offset) {
if (GlobalVariable *GV = dyn_cast<GlobalVariable>(this)) {
if (GV->hasInitializer() && isa<ConstantArray>(GV->getInitializer())) {
ConstantArray *Init = cast<ConstantArray>(GV->getInitializer());
if (Init->isString()) {
std::string Result = Init->getAsString();
if (Offset < Result.size()) {
// If we are pointing INTO The string, erase the beginning...
Result.erase(Result.begin(), Result.begin()+Offset);
// Take off the null terminator, and any string fragments after it.
if (Chop) {
std::string::size_type NullPos = Result.find_first_of((char)0);
if (NullPos != std::string::npos)
Result.erase(Result.begin()+NullPos, Result.end());
}
return Result;
}
}
}
} else if (ConstantExpr *CE = dyn_cast<ConstantExpr>(this)) {
if (CE->getOpcode() == Instruction::GetElementPtr) {
// Turn a gep into the specified offset.
if (CE->getNumOperands() == 3 &&
cast<Constant>(CE->getOperand(1))->isNullValue() &&
isa<ConstantInt>(CE->getOperand(2))) {
Offset += cast<ConstantInt>(CE->getOperand(2))->getZExtValue();
return CE->getOperand(0)->getStringValue(Chop, Offset);
}
}
}
return "";
}

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@ -28,7 +28,6 @@
#include "llvm/IntrinsicInst.h"
#include "llvm/Constants.h"
#include "llvm/GlobalVariable.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/CodeGen/MachineDebugInfoDesc.h"
#include "llvm/CodeGen/MachineModuleInfo.h"
using namespace llvm;
@ -59,20 +58,20 @@ Value *DbgInfoIntrinsic::StripCast(Value *C) {
/// DbgStopPointInst - This represents the llvm.dbg.stoppoint instruction.
///
Value *DbgStopPointInst::getFileName() const {
std::string DbgStopPointInst::getFileName() const {
// Once the operand indices are verified, update this assert
assert(LLVMDebugVersion == (6 << 16) && "Verify operand indices");
GlobalVariable *GV = cast<GlobalVariable>(getContext());
if (!GV->hasInitializer()) return NULL;
if (!GV->hasInitializer()) return "";
ConstantStruct *CS = cast<ConstantStruct>(GV->getInitializer());
return CS->getOperand(4);
return CS->getOperand(3)->getStringValue();
}
Value *DbgStopPointInst::getDirectory() const {
std::string DbgStopPointInst::getDirectory() const {
// Once the operand indices are verified, update this assert
assert(LLVMDebugVersion == (6 << 16) && "Verify operand indices");
GlobalVariable *GV = cast<GlobalVariable>(getContext());
if (!GV->hasInitializer()) return NULL;
if (!GV->hasInitializer()) return "";
ConstantStruct *CS = cast<ConstantStruct>(GV->getInitializer());
return CS->getOperand(4);
return CS->getOperand(4)->getStringValue();
}