X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FTransforms%2FLevelRaise.cpp;h=f246116a2ee7822ee0ce363d5f56ecb05d98a88e;hb=c966a2acee176369be2f901e32c346c176b7f772;hp=dfe92ee234c39b7fde9b0641da5cdc45dfd4204c;hpb=d5b48ca422089a17fa6ba2945d3f8b46fff7d689;p=oota-llvm.git diff --git a/lib/Transforms/LevelRaise.cpp b/lib/Transforms/LevelRaise.cpp index dfe92ee234c..f246116a2ee 100644 --- a/lib/Transforms/LevelRaise.cpp +++ b/lib/Transforms/LevelRaise.cpp @@ -2,55 +2,55 @@ // // This file implements the 'raising' part of the LevelChange API. This is // useful because, in general, it makes the LLVM code terser and easier to -// analyze. Note that it is good to run DCE after doing this transformation. -// -// Eliminate silly things in the source that do not effect the level, but do -// clean up the code: -// * Casts of casts -// - getelementptr/load & getelementptr/store are folded into a direct -// load or store -// - Convert this code (for both alloca and malloc): -// %reg110 = shl uint %n, ubyte 2 ;; -// %reg108 = alloca ubyte, uint %reg110 ;; -// %cast76 = cast ubyte* %reg108 to uint* ;; -// To: %cast76 = alloca uint, uint %n -// Convert explicit addressing to use getelementptr instruction where possible -// - ... -// -// Convert explicit addressing on pointers to use getelementptr instruction. -// - If a pointer is used by arithmetic operation, insert an array casted -// version into the source program, only for the following pointer types: -// * Method argument pointers -// - Pointers returned by alloca or malloc -// - Pointers returned by function calls -// - If a pointer is indexed with a value scaled by a constant size equal -// to the element size of the array, the expression is replaced with a -// getelementptr instruction. +// analyze. // //===----------------------------------------------------------------------===// -#include "llvm/Transforms/LevelChange.h" +#include "llvm/Transforms/RaisePointerReferences.h" +#include "llvm/Transforms/Utils/Local.h" #include "TransformInternals.h" -#include "llvm/Method.h" -#include "llvm/Support/STLExtras.h" #include "llvm/iOther.h" #include "llvm/iMemory.h" -#include "llvm/ConstPoolVals.h" -#include "llvm/Optimizations/ConstantHandling.h" -#include "llvm/Optimizations/DCE.h" +#include "llvm/Pass.h" +#include "llvm/ConstantHandling.h" #include "llvm/Analysis/Expressions.h" +#include "llvm/Analysis/Verifier.h" +#include "llvm/Transforms/Utils/BasicBlockUtils.h" +#include "Support/STLExtras.h" +#include "Support/Statistic.h" +#include "Support/CommandLine.h" #include +using std::cerr; + +// StartInst - This enables the -raise-start-inst=foo option to cause the level +// raising pass to start at instruction "foo", which is immensely useful for +// debugging! +// +static cl::opt +StartInst("raise-start-inst", cl::Hidden, cl::value_desc("inst name"), + cl::desc("Start raise pass at the instruction with the specified name")); + +static Statistic<> +NumLoadStorePeepholes("raise", "Number of load/store peepholes"); + +static Statistic<> +NumGEPInstFormed("raise", "Number of other getelementptr's formed"); + +static Statistic<> +NumExprTreesConv("raise", "Number of expression trees converted"); -#include "llvm/Assembly/Writer.h" +static Statistic<> +NumCastOfCast("raise", "Number of cast-of-self removed"); + +static Statistic<> +NumDCEorCP("raise", "Number of insts DCEd or constprop'd"); + +static Statistic<> +NumVarargCallChanges("raise", "Number of vararg call peepholes"); -//#define DEBUG_PEEPHOLE_INSTS 1 -#ifdef DEBUG_PEEPHOLE_INSTS #define PRINT_PEEPHOLE(ID, NUM, I) \ - cerr << "Inst P/H " << ID << "[" << NUM << "] " << I; -#else -#define PRINT_PEEPHOLE(ID, NUM, I) -#endif + DEBUG(std::cerr << "Inst P/H " << ID << "[" << NUM << "] " << I) #define PRINT_PEEPHOLE1(ID, I1) do { PRINT_PEEPHOLE(ID, 0, I1); } while (0) #define PRINT_PEEPHOLE2(ID, I1, I2) \ @@ -68,212 +68,80 @@ // cast instruction would cause the underlying bits to change. // static inline bool isReinterpretingCast(const CastInst *CI) { - return !losslessCastableTypes(CI->getOperand(0)->getType(), CI->getType()); + return!CI->getOperand(0)->getType()->isLosslesslyConvertableTo(CI->getType()); } - - -// DoInsertArrayCast - If the argument value has a pointer type, and if the -// argument value is used as an array, insert a cast before the specified -// basic block iterator that casts the value to an array pointer. Return the -// new cast instruction (in the CastResult var), or null if no cast is inserted. +// Peephole optimize the following instructions: +// %t1 = cast ? to x * +// %t2 = add x * %SP, %t1 ;; Constant must be 2nd operand // -static bool DoInsertArrayCast(Method *CurMeth, Value *V, BasicBlock *BB, - BasicBlock::iterator &InsertBefore, - CastInst *&CastResult) { - const PointerType *ThePtrType = dyn_cast(V->getType()); - if (!ThePtrType) return false; - bool InsertCast = false; - - for (Value::use_iterator I = V->use_begin(), E = V->use_end(); I != E; ++I) { - Instruction *Inst = cast(*I); - switch (Inst->getOpcode()) { - default: break; // Not an interesting use... - case Instruction::Add: // It's being used as an array index! - //case Instruction::Sub: - InsertCast = true; - break; - case Instruction::Cast: // There is already a cast instruction! - if (const PointerType *PT = dyn_cast(Inst->getType())) - if (const ArrayType *AT = dyn_cast(PT->getValueType())) - if (AT->getElementType() == ThePtrType->getValueType()) { - // Cast already exists! Return the existing one! - CastResult = cast(Inst); - return false; // No changes made to program though... - } - break; - } - } - - if (!InsertCast) return false; // There is no reason to insert a cast! - - // Insert a cast! - const Type *ElTy = ThePtrType->getValueType(); - const PointerType *DestTy = PointerType::get(ArrayType::get(ElTy)); - - CastResult = new CastInst(V, DestTy); - BB->getInstList().insert(InsertBefore, CastResult); - //cerr << "Inserted cast: " << CastResult; - return true; // Made a change! -} - - -// DoInsertArrayCasts - Loop over all "incoming" values in the specified method, -// inserting a cast for pointer values that are used as arrays. For our -// purposes, an incoming value is considered to be either a value that is -// either a method parameter, a value created by alloca or malloc, or a value -// returned from a function call. All casts are kept attached to their original -// values through the PtrCasts map. +// Into: %t3 = getelementptr {<...>} * %SP, +// %t2 = cast * %t3 to {<...>}* // -static bool DoInsertArrayCasts(Method *M, map &PtrCasts) { - assert(!M->isExternal() && "Can't handle external methods!"); +static bool HandleCastToPointer(BasicBlock::iterator BI, + const PointerType *DestPTy) { + CastInst &CI = cast(*BI); + if (CI.use_empty()) return false; - // Insert casts for all arguments to the function... - bool Changed = false; - BasicBlock *CurBB = M->front(); - BasicBlock::iterator It = CurBB->begin(); - for (Method::ArgumentListType::iterator AI = M->getArgumentList().begin(), - AE = M->getArgumentList().end(); AI != AE; ++AI) { - CastInst *TheCast = 0; - if (DoInsertArrayCast(M, *AI, CurBB, It, TheCast)) { - It = CurBB->begin(); // We might have just invalidated the iterator! - Changed = true; // Yes we made a change - ++It; // Insert next cast AFTER this one... + // Scan all of the uses, looking for any uses that are not add + // instructions. If we have non-adds, do not make this transformation. + // + for (Value::use_iterator I = CI.use_begin(), E = CI.use_end(); + I != E; ++I) { + if (BinaryOperator *BO = dyn_cast(*I)) { + if (BO->getOpcode() != Instruction::Add || + // Avoid add sbyte* %X, %X cases... + BO->getOperand(0) == BO->getOperand(1)) + return false; + } else { + return false; } - - if (TheCast) // Is there a cast associated with this value? - PtrCasts[*AI] = TheCast; // Yes, add it to the map... } - // TODO: insert casts for alloca, malloc, and function call results. Also, - // look for pointers that already have casts, to add to the map. - - return Changed; -} + std::vector Indices; + Value *Src = CI.getOperand(0); + const Type *Result = ConvertableToGEP(DestPTy, Src, Indices, &BI); + if (Result == 0) return false; // Not convertable... + PRINT_PEEPHOLE2("cast-add-to-gep:in", Src, CI); - - -// DoElminatePointerArithmetic - Loop over each incoming pointer variable, -// replacing indexing arithmetic with getelementptr calls. -// -static bool DoEliminatePointerArithmetic(const pair &Val) { - Value *V = Val.first; // The original pointer - CastInst *CV = Val.second; // The array casted version of the pointer... - - for (Value::use_iterator I = V->use_begin(), E = V->use_end(); I != E; ++I) { - Instruction *Inst = cast(*I); - if (Inst->getOpcode() != Instruction::Add) - continue; // We only care about add instructions - - BinaryOperator *Add = cast(Inst); - - // Make sure the array is the first operand of the add expression... - if (Add->getOperand(0) != V) - Add->swapOperands(); - - // Get the amount added to the pointer value... - Value *AddAmount = Add->getOperand(1); - + // If we have a getelementptr capability... transform all of the + // add instruction uses into getelementptr's. + while (!CI.use_empty()) { + BinaryOperator *I = cast(*CI.use_begin()); + assert(I->getOpcode() == Instruction::Add && I->getNumOperands() == 2 && + "Use is not a valid add instruction!"); - } - return false; -} - - -// Peephole Malloc instructions: we take a look at the use chain of the -// malloc instruction, and try to find out if the following conditions hold: -// 1. The malloc is of the form: 'malloc [sbyte], uint ' -// 2. The only users of the malloc are cast & add instructions -// 3. Of the cast instructions, there is only one destination pointer type -// [RTy] where the size of the pointed to object is equal to the number -// of bytes allocated. -// -// If these conditions hold, we convert the malloc to allocate an [RTy] -// element. This should be extended in the future to handle arrays. TODO -// -static bool PeepholeMallocInst(BasicBlock *BB, BasicBlock::iterator &BI) { - MallocInst *MI = cast(*BI); - if (!MI->isArrayAllocation()) return false; // No array allocation? - - ConstPoolUInt *Amt = dyn_cast(MI->getArraySize()); - if (Amt == 0 || MI->getAllocatedType() != ArrayType::get(Type::SByteTy)) - return false; + // Get the value added to the cast result pointer... + Value *OtherPtr = I->getOperand((I->getOperand(0) == &CI) ? 1 : 0); + + Instruction *GEP = new GetElementPtrInst(OtherPtr, Indices, I->getName()); + PRINT_PEEPHOLE1("cast-add-to-gep:i", I); + + if (GEP->getType() == I->getType()) { + // Replace the old add instruction with the shiny new GEP inst + ReplaceInstWithInst(I, GEP); + } else { + // If the type produced by the gep instruction differs from the original + // add instruction type, insert a cast now. + // - // Get the number of bytes allocated... - unsigned Size = Amt->getValue(); - const Type *ResultTy = 0; + // Insert the GEP instruction before the old add instruction... + I->getParent()->getInstList().insert(I, GEP); - // Loop over all of the uses of the malloc instruction, inspecting casts. - for (Value::use_iterator I = MI->use_begin(), E = MI->use_end(); - I != E; ++I) { - if (CastInst *CI = dyn_cast(*I)) { - //cerr << "\t" << CI; - - // We only work on casts to pointer types for sure, be conservative - if (!isa(CI->getType())) { - cerr << "Found cast of malloc value to non pointer type:\n" << CI; - return false; - } + PRINT_PEEPHOLE1("cast-add-to-gep:o", GEP); + GEP = new CastInst(GEP, I->getType()); - const Type *DestTy = cast(CI->getType())->getValueType(); - if (isa(DestTy)) { - cerr << "Avoided malloc conversion because of type: " << DestTy - << " TODO.\n"; - return false; - } - if (TD.getTypeSize(DestTy) == Size && DestTy != ResultTy) { - // Does the size of the allocated type match the number of bytes - // allocated? - // - if (ResultTy == 0) { - ResultTy = DestTy; // Keep note of this for future uses... - } else { - // It's overdefined! We don't know which type to convert to! - return false; - } - } + // Replace the old add instruction with the shiny new GEP inst + ReplaceInstWithInst(I, GEP); } - } - - // If we get this far, we have either found, or not, a type that is cast to - // that is of the same size as the malloc instruction. - if (!ResultTy) return false; - // Now we check to see if we can convert the return value of malloc to the - // specified pointer type. All this is moot if we can't. - // - ValueTypeCache ConvertedTypes; - if (RetValConvertableToType(MI, PointerType::get(ResultTy), ConvertedTypes)) { - // Yup, it's convertable, do the transformation now! - PRINT_PEEPHOLE1("mall-refine:in ", MI); - - // Create a new malloc instruction, and insert it into the method... - MallocInst *NewMI = new MallocInst(PointerType::get(ResultTy)); - NewMI->setName(MI->getName()); - MI->setName(""); - BI = BB->getInstList().insert(BI, NewMI)+1; - - // Create a new cast instruction to cast it to the old type... - CastInst *NewCI = new CastInst(NewMI, MI->getType()); - BB->getInstList().insert(BI, NewCI); - - // Move all users of the old malloc instruction over to use the new cast... - MI->replaceAllUsesWith(NewCI); - - ValueMapCache ValueMap; - ConvertUsersType(NewCI, NewMI, ValueMap); // This will delete MI! - - BI = BB->begin(); // Rescan basic block. BI might be invalidated. - PRINT_PEEPHOLE1("mall-refine:out", NewMI); - return true; + PRINT_PEEPHOLE1("cast-add-to-gep:o", GEP); } - return false; + return true; } - - // Peephole optimize the following instructions: // %t1 = cast ulong to {<...>} * // %t2 = add {<...>} * %SP, %t1 ;; Constant must be 2nd operand @@ -288,174 +156,42 @@ static bool PeepholeMallocInst(BasicBlock *BB, BasicBlock::iterator &BI) { // static bool PeepholeOptimizeAddCast(BasicBlock *BB, BasicBlock::iterator &BI, Value *AddOp1, CastInst *AddOp2) { - Value *OffsetVal = AddOp2->getOperand(0); - Value *SrcPtr; // Of type pointer to struct... - const StructType *StructTy; + const CompositeType *CompTy; + Value *OffsetVal = AddOp2->getOperand(0); + Value *SrcPtr; // Of type pointer to struct... - if ((StructTy = getPointedToStruct(AddOp1->getType()))) { + if ((CompTy = getPointedToComposite(AddOp1->getType()))) { SrcPtr = AddOp1; // Handle the first case... } else if (CastInst *AddOp1c = dyn_cast(AddOp1)) { SrcPtr = AddOp1c->getOperand(0); // Handle the second case... - StructTy = getPointedToStruct(SrcPtr->getType()); + CompTy = getPointedToComposite(SrcPtr->getType()); } // Only proceed if we have detected all of our conditions successfully... - if (!StructTy || !SrcPtr || !OffsetVal->getType()->isIntegral()) - return false; - - // See if the cast is of an integer expression that is either a constant, - // or a value scaled by some amount with a possible offset. - // - analysis::ExprType Expr = analysis::ClassifyExpression(OffsetVal); - unsigned Offset = 0, Scale = 1; - - // The expression must either be a constant, or a scaled index to be useful - if (!Expr.Offset && !Expr.Scale) + if (!CompTy || !SrcPtr || !OffsetVal->getType()->isInteger()) return false; - // Get the offset value if it exists... - if (Expr.Offset) { - if (ConstPoolSInt *CPSI = dyn_cast(Expr.Offset)) - Offset = (unsigned)CPSI->getValue(); - else { - ConstPoolUInt *CPUI = cast(Expr.Offset); - Offset = (unsigned)CPUI->getValue(); - } - assert(Offset != 0 && "Expression analysis failure!"); - } + std::vector Indices; + if (!ConvertableToGEP(SrcPtr->getType(), OffsetVal, Indices, &BI)) + return false; // Not convertable... perhaps next time - // Get the scale value if it exists... - if (Expr.Scale) { - if (ConstPoolSInt *CPSI = dyn_cast(Expr.Scale)) - Scale = (unsigned)CPSI->getValue(); - else { - ConstPoolUInt *CPUI = cast(Expr.Scale); - Scale = (unsigned)CPUI->getValue(); - } - assert(Scale != 1 && "Expression analysis failure!"); - } - - // Check to make sure the offset is not negative or really large, outside the - // scope of this structure... - // - if (Offset >= TD.getTypeSize(StructTy)) - return false; - - const StructLayout *SL = TD.getStructLayout(StructTy); - vector Offsets; - unsigned ActualOffset = Offset; - const Type *ElTy = getStructOffsetType(StructTy, ActualOffset, Offsets); - - if (getPointedToStruct(AddOp1->getType())) { // case 1 + if (getPointedToComposite(AddOp1->getType())) { // case 1 PRINT_PEEPHOLE2("add-to-gep1:in", AddOp2, *BI); } else { PRINT_PEEPHOLE3("add-to-gep2:in", AddOp1, AddOp2, *BI); } - GetElementPtrInst *GEP = new GetElementPtrInst(SrcPtr, Offsets); - //AddOp2->getName()); - BI = BB->getInstList().insert(BI, GEP)+1; - - Instruction *AddrSrc = GEP; - - if (const ArrayType *AT = dyn_cast(ElTy)) { - assert((Scale == 1 || Offset == ActualOffset) && - "Cannot handle scaled expression and unused offset in the same " - "instruction until after GEP array works!"); - - // Check to see if we have bottomed out INSIDE of an array reference.. - // - if (Offset != ActualOffset) { - // Insert a cast of the "rest" of the offset to the appropriate - // pointer type. - CastInst *OffInst = - new CastInst(ConstPoolUInt::get(Type::ULongTy, - Offset-ActualOffset), - GEP->getType()); - BI = BB->getInstList().insert(BI, OffInst)+1; - - // Now insert an ADD to actually adjust the pointer... - Instruction *AddInst = - BinaryOperator::create(Instruction::Add, GEP, OffInst); - BI = BB->getInstList().insert(BI, AddInst)+1; + GetElementPtrInst *GEP = new GetElementPtrInst(SrcPtr, Indices, + AddOp2->getName(), BI); - PRINT_PEEPHOLE2("add-to-gep:out1", OffInst, AddInst); - - AddrSrc = AddInst; - } else if (Scale != 1) { - // If the scale factor occurs, then this means that there is an index into - // this element of the array. Check to make sure the scale factor is the - // same as the size of the datatype that we are dealing with. - // - assert(Scale == TD.getTypeSize(AT->getElementType()) && - "Scaling by something other than the array element size!!"); - - // TODO: In the future, we will not want to cast the index and scale to - // pointer types first. We will want to create a GEP directly here. - - // Now we must actually perform the scaling operation to get an - // appropriate value to add in... but the scale has to be done in the - // appropriate destination pointer type, so cast the index value now. - // - // Cast the base index pointer - CastInst *IdxValue = new CastInst(Expr.Var, GEP->getType()); - BI = BB->getInstList().insert(BI, IdxValue)+1; - - // Case the scale amount as well... - CastInst *ScaleAmt = - new CastInst(ConstPoolUInt::get(Type::ULongTy, Scale), GEP->getType()); - BI = BB->getInstList().insert(BI, ScaleAmt)+1; - - // Insert the multiply now. Make sure to make the constant the second arg - Instruction *ScaledVal = - BinaryOperator::create(Instruction::Mul, IdxValue, ScaleAmt); - BI = BB->getInstList().insert(BI, ScaledVal)+1; - - // Now insert an ADD to actually adjust the pointer... - Instruction *AddInst = - BinaryOperator::create(Instruction::Add, GEP, ScaledVal); - BI = BB->getInstList().insert(BI, AddInst)+1; - - PRINT_PEEPHOLE4("add-to-gep:out1", IdxValue, ScaleAmt, ScaledVal, - AddInst); - AddrSrc = AddInst; - } - - // Insert a cast of the pointer to array of X to be a pointer to the - // element of the array. - // - // Insert a cast of the "rest" of the offset to the appropriate - // pointer type. - CastInst *ACI = new CastInst(AddrSrc, AT->getElementType()); - BI = BB->getInstList().insert(BI, ACI)+1; - AddrSrc = ACI; - - } else { - assert(Offset == ActualOffset && "GEP to middle of non array!"); - assert(Scale == 1 && "Scale factor for expr that is not an array idx!"); - } - - Instruction *NCI = new CastInst(AddrSrc, AddOp1->getType()); + Instruction *NCI = new CastInst(GEP, AddOp1->getType()); ReplaceInstWithInst(BB->getInstList(), BI, NCI); PRINT_PEEPHOLE2("add-to-gep:out", GEP, NCI); return true; } -// Peephole optimize the following instructions: -// %t1 = cast int (uint) * %reg111 to uint (...) * -// %t2 = call uint (...) * %cast111( uint %key ) -// -// Into: %t3 = call int (uint) * %reg111( uint %key ) -// %t2 = cast int %t3 to uint -// -static bool PeepholeCallInst(BasicBlock *BB, BasicBlock::iterator &BI) { - CallInst *CI = cast(*BI); - return false; -} - - static bool PeepholeOptimize(BasicBlock *BB, BasicBlock::iterator &BI) { - Instruction *I = *BI; + Instruction *I = BI; if (CastInst *CI = dyn_cast(I)) { Value *Src = CI->getOperand(0); @@ -471,74 +207,87 @@ static bool PeepholeOptimize(BasicBlock *BB, BasicBlock::iterator &BI) { PRINT_PEEPHOLE1("cast-of-self-ty", CI); CI->replaceAllUsesWith(Src); if (!Src->hasName() && CI->hasName()) { - string Name = CI->getName(); + std::string Name = CI->getName(); CI->setName(""); Src->setName(Name, BB->getParent()->getSymbolTable()); } + + // DCE the instruction now, to avoid having the iterative version of DCE + // have to worry about it. + // + BI = BB->getInstList().erase(BI); + + ++NumCastOfCast; return true; } - // Peephole optimize the following instructions: - // %tmp = cast %V to - // %V = cast %tmp to ; Where ty & ty2 are same size - // - // Into: cast %V to - // - if (SrcI) - if (CastInst *CSrc = dyn_cast(SrcI)) - if (isReinterpretingCast(CI) + isReinterpretingCast(CSrc) < 2) { - // We can only do c-c elimination if, at most, one cast does a - // reinterpretation of the input data. - // - // If legal, make this cast refer the the original casts argument! - // - PRINT_PEEPHOLE2("cast-cast:in ", CI, CSrc); - CI->setOperand(0, CSrc->getOperand(0)); - PRINT_PEEPHOLE1("cast-cast:out", CI); - return true; - } - // Check to see if it's a cast of an instruction that does not depend on the // specific type of the operands to do it's job. if (!isReinterpretingCast(CI)) { ValueTypeCache ConvertedTypes; - if (RetValConvertableToType(CI, Src->getType(), ConvertedTypes)) { - PRINT_PEEPHOLE2("CAST-DEST-EXPR-CONV:in ", CI, Src); - -#ifdef DEBUG_PEEPHOLE_INSTS - cerr << "\nCONVERTING EXPR TYPE:\n"; -#endif - ValueMapCache ValueMap; - ConvertUsersType(CI, Src, ValueMap); // This will delete CI! - BI = BB->begin(); // Rescan basic block. BI might be invalidated. - PRINT_PEEPHOLE1("CAST-DEST-EXPR-CONV:out", Src); -#ifdef DEBUG_PEEPHOLE_INSTS - cerr << "DONE CONVERTING EXPR TYPE: \n\n";// << BB->getParent(); -#endif - return true; - } else { - ConvertedTypes.clear(); - if (ExpressionConvertableToType(Src, DestTy, ConvertedTypes)) { - PRINT_PEEPHOLE2("CAST-SRC-EXPR-CONV:in ", CI, Src); + // Check to see if we can convert the source of the cast to match the + // destination type of the cast... + // + ConvertedTypes[CI] = CI->getType(); // Make sure the cast doesn't change + if (ExpressionConvertableToType(Src, DestTy, ConvertedTypes)) { + PRINT_PEEPHOLE3("CAST-SRC-EXPR-CONV:in ", Src, CI, BB->getParent()); -#ifdef DEBUG_PEEPHOLE_INSTS - cerr << "\nCONVERTING SRC EXPR TYPE:\n"; -#endif + DEBUG(cerr << "\nCONVERTING SRC EXPR TYPE:\n"); + { // ValueMap must be destroyed before function verified! ValueMapCache ValueMap; Value *E = ConvertExpressionToType(Src, DestTy, ValueMap); - if (ConstPoolVal *CPV = dyn_cast(E)) - CI->replaceAllUsesWith(CPV); - BI = BB->begin(); // Rescan basic block. BI might be invalidated. + if (Constant *CPV = dyn_cast(E)) + CI->replaceAllUsesWith(CPV); + PRINT_PEEPHOLE1("CAST-SRC-EXPR-CONV:out", E); -#ifdef DEBUG_PEEPHOLE_INSTS - cerr << "DONE CONVERTING SRC EXPR TYPE: \n\n";// << BB->getParent(); -#endif - return true; + DEBUG(cerr << "DONE CONVERTING SRC EXPR TYPE: \n" << BB->getParent()); } + + DEBUG(assert(verifyFunction(*BB->getParent()) == false && + "Function broken!")); + BI = BB->begin(); // Rescan basic block. BI might be invalidated. + ++NumExprTreesConv; + return true; + } + + // Check to see if we can convert the users of the cast value to match the + // source type of the cast... + // + ConvertedTypes.clear(); + // Make sure the source doesn't change type + ConvertedTypes[Src] = Src->getType(); + if (ValueConvertableToType(CI, Src->getType(), ConvertedTypes)) { + PRINT_PEEPHOLE3("CAST-DEST-EXPR-CONV:in ", Src, CI, BB->getParent()); + + DEBUG(cerr << "\nCONVERTING EXPR TYPE:\n"); + { // ValueMap must be destroyed before function verified! + ValueMapCache ValueMap; + ConvertValueToNewType(CI, Src, ValueMap); // This will delete CI! + } + + PRINT_PEEPHOLE1("CAST-DEST-EXPR-CONV:out", Src); + DEBUG(cerr << "DONE CONVERTING EXPR TYPE: \n\n" << BB->getParent()); + + DEBUG(assert(verifyFunction(*BB->getParent()) == false && + "Function broken!")); + BI = BB->begin(); // Rescan basic block. BI might be invalidated. + ++NumExprTreesConv; + return true; + } + } + + // Otherwise find out it this cast is a cast to a pointer type, which is + // then added to some other pointer, then loaded or stored through. If + // so, convert the add into a getelementptr instruction... + // + if (const PointerType *DestPTy = dyn_cast(DestTy)) { + if (HandleCastToPointer(BI, DestPTy)) { + BI = BB->begin(); // Rescan basic block. BI might be invalidated. + ++NumGEPInstFormed; + return true; } - } // Check to see if we are casting from a structure pointer to a pointer to @@ -551,8 +300,7 @@ static bool PeepholeOptimize(BasicBlock *BB, BasicBlock::iterator &BI) { // Into: %t2 = getelementptr {<...>} * %StructPtr, <0, 0, 0, ...> // %t1 = cast * %t1 to * // -#if 1 - if (const StructType *STy = getPointedToStruct(Src->getType())) + if (const CompositeType *CTy = getPointedToComposite(Src->getType())) if (const PointerType *DestPTy = dyn_cast(DestTy)) { // Loop over uses of the cast, checking for add instructions. If an add @@ -572,26 +320,36 @@ static bool PeepholeOptimize(BasicBlock *BB, BasicBlock::iterator &BI) { // type. // if (!HasAddUse) { - const Type *DestPointedTy = DestPTy->getValueType(); + const Type *DestPointedTy = DestPTy->getElementType(); unsigned Depth = 1; - const StructType *CurSTy = STy; + const CompositeType *CurCTy = CTy; const Type *ElTy = 0; - while (CurSTy) { - - // Check for a zero element struct type... if we have one, bail. - if (CurSTy->getElementTypes().size() == 0) break; + + // Build the index vector, full of all zeros + std::vector Indices; + Indices.push_back(ConstantSInt::get(Type::LongTy, 0)); + while (CurCTy && !isa(CurCTy)) { + if (const StructType *CurSTy = dyn_cast(CurCTy)) { + // Check for a zero element struct type... if we have one, bail. + if (CurSTy->getElementTypes().size() == 0) break; - // Grab the first element of the struct type, which must lie at - // offset zero in the struct. - // - ElTy = CurSTy->getElementTypes()[0]; + // Grab the first element of the struct type, which must lie at + // offset zero in the struct. + // + ElTy = CurSTy->getElementTypes()[0]; + } else { + ElTy = cast(CurCTy)->getElementType(); + } + + // Insert a zero to index through this type... + Indices.push_back(Constant::getNullValue(CurCTy->getIndexType())); // Did we find what we're looking for? - if (losslessCastableTypes(ElTy, DestPointedTy)) break; + if (ElTy->isLosslesslyConvertableTo(DestPointedTy)) break; // Nope, go a level deeper. ++Depth; - CurSTy = dyn_cast(ElTy); + CurCTy = dyn_cast(ElTy); ElTy = 0; } @@ -599,15 +357,11 @@ static bool PeepholeOptimize(BasicBlock *BB, BasicBlock::iterator &BI) { if (ElTy) { PRINT_PEEPHOLE1("cast-for-first:in", CI); - // Build the index vector, full of all zeros - vector Indices(Depth, - ConstPoolUInt::get(Type::UByteTy,0)); + std::string Name = CI->getName(); CI->setName(""); // Insert the new T cast instruction... stealing old T's name GetElementPtrInst *GEP = new GetElementPtrInst(Src, Indices, - CI->getName()); - CI->setName(""); - BI = BB->getInstList().insert(BI, GEP)+1; + Name, BI); // Make the old cast instruction reference the new GEP instead of // the old src value. @@ -615,44 +369,15 @@ static bool PeepholeOptimize(BasicBlock *BB, BasicBlock::iterator &BI) { CI->setOperand(0, GEP); PRINT_PEEPHOLE2("cast-for-first:out", GEP, CI); + ++NumGEPInstFormed; return true; } } } -#endif - -#if 1 - } else if (MallocInst *MI = dyn_cast(I)) { - if (PeepholeMallocInst(BB, BI)) return true; - - } else if (CallInst *CI = dyn_cast(I)) { - if (PeepholeCallInst(BB, BI)) return true; } else if (StoreInst *SI = dyn_cast(I)) { Value *Val = SI->getOperand(0); - Value *Pointer = SI->getPtrOperand(); - - // Peephole optimize the following instructions: - // %t1 = getelementptr {<...>} * %StructPtr, - // store %v, * %t1 - // - // Into: store %v, {<...>} * %StructPtr, - // - if (GetElementPtrInst *GEP = dyn_cast(Pointer)) { - // Append any indices that the store instruction has onto the end of the - // ones that the GEP is carrying... - // - vector Indices(GEP->getIndices()); - Indices.insert(Indices.end(), SI->getIndices().begin(), - SI->getIndices().end()); - - PRINT_PEEPHOLE2("gep-store:in", GEP, SI); - ReplaceInstWithInst(BB->getInstList(), BI, - SI = new StoreInst(Val, GEP->getPtrOperand(), - Indices)); - PRINT_PEEPHOLE1("gep-store:out", SI); - return true; - } + Value *Pointer = SI->getPointerOperand(); // Peephole optimize the following instructions: // %t = cast * %P to * ;; If T1 is losslessly convertable to T2 @@ -662,99 +387,111 @@ static bool PeepholeOptimize(BasicBlock *BB, BasicBlock::iterator &BI) { // %t = cast %V to // store %t2, * %P // + // Note: This is not taken care of by expr conversion because there might + // not be a cast available for the store to convert the incoming value of. + // This code is basically here to make sure that pointers don't have casts + // if possible. + // if (CastInst *CI = dyn_cast(Pointer)) if (Value *CastSrc = CI->getOperand(0)) // CSPT = CastSrcPointerType - if (PointerType *CSPT = dyn_cast(CastSrc->getType())) - if (losslessCastableTypes(Val->getType(), // convertable types! - CSPT->getValueType()) && - !SI->hasIndices()) { // No subscripts yet! + if (const PointerType *CSPT = dyn_cast(CastSrc->getType())) + // convertable types? + if (Val->getType()->isLosslesslyConvertableTo(CSPT->getElementType())) { PRINT_PEEPHOLE3("st-src-cast:in ", Pointer, Val, SI); // Insert the new T cast instruction... stealing old T's name - CastInst *NCI = new CastInst(Val, CSPT->getValueType(), - CI->getName()); - CI->setName(""); - BI = BB->getInstList().insert(BI, NCI)+1; + std::string Name(CI->getName()); CI->setName(""); + CastInst *NCI = new CastInst(Val, CSPT->getElementType(), + Name, BI); // Replace the old store with a new one! ReplaceInstWithInst(BB->getInstList(), BI, SI = new StoreInst(NCI, CastSrc)); PRINT_PEEPHOLE3("st-src-cast:out", NCI, CastSrc, SI); + ++NumLoadStorePeepholes; return true; } - } else if (LoadInst *LI = dyn_cast(I)) { - Value *Pointer = LI->getPtrOperand(); + Value *Pointer = LI->getOperand(0); + const Type *PtrElType = + cast(Pointer->getType())->getElementType(); // Peephole optimize the following instructions: - // %t1 = getelementptr {<...>} * %StructPtr, - // %V = load * %t1 + // %Val = cast * to * ;; If T1 is losslessly convertable to T2 + // %t = load * %P // - // Into: load {<...>} * %StructPtr, - // - if (GetElementPtrInst *GEP = dyn_cast(Pointer)) { - // Append any indices that the load instruction has onto the end of the - // ones that the GEP is carrying... - // - vector Indices(GEP->getIndices()); - Indices.insert(Indices.end(), LI->getIndices().begin(), - LI->getIndices().end()); - - PRINT_PEEPHOLE2("gep-load:in", GEP, LI); - ReplaceInstWithInst(BB->getInstList(), BI, - LI = new LoadInst(GEP->getPtrOperand(), - Indices)); - PRINT_PEEPHOLE1("gep-load:out", LI); - return true; - } - - - // Peephole optimize the following instructions: - // %t1 = cast * %t0 to * - // %V = load * %t1 - // - // Into: %t1 = load * %t0 - // %V = cast %t1 to + // Into: + // %t = load * %P + // %Val = cast to // - // The idea behind this transformation is that if the expression type - // conversion engine could not convert the cast into some other nice form, - // that there is something fundementally wrong with the current shape of - // the program. Move the cast through the load and try again. This will - // leave the original cast instruction, to presumably become dead. + // Note: This is not taken care of by expr conversion because there might + // not be a cast available for the store to convert the incoming value of. + // This code is basically here to make sure that pointers don't have casts + // if possible. // - if (CastInst *CI = dyn_cast(Pointer)) { - Value *SrcVal = CI->getOperand(0); - const PointerType *SrcTy = dyn_cast(SrcVal->getType()); - const Type *ElTy = SrcTy ? SrcTy->getValueType() : 0; - - // Make sure that nothing will be lost in the new cast... - if (SrcTy && losslessCastableTypes(ElTy, LI->getType())) { - PRINT_PEEPHOLE2("CL-LoadCast:in ", CI, LI); - - string CName = CI->getName(); CI->setName(""); - LoadInst *NLI = new LoadInst(SrcVal, LI->getName()); - LI->setName(""); // Take over the old load's name + if (CastInst *CI = dyn_cast(Pointer)) + if (Value *CastSrc = CI->getOperand(0)) // CSPT = CastSrcPointerType + if (const PointerType *CSPT = dyn_cast(CastSrc->getType())) + // convertable types? + if (PtrElType->isLosslesslyConvertableTo(CSPT->getElementType())) { + PRINT_PEEPHOLE2("load-src-cast:in ", Pointer, LI); - // Insert the load before the old load - BI = BB->getInstList().insert(BI, NLI)+1; + // Create the new load instruction... loading the pre-casted value + LoadInst *NewLI = new LoadInst(CastSrc, LI->getName(), BI); + + // Insert the new T cast instruction... stealing old T's name + CastInst *NCI = new CastInst(NewLI, LI->getType(), CI->getName()); - // Replace the old load with a new cast... - ReplaceInstWithInst(BB->getInstList(), BI, - CI = new CastInst(NLI, LI->getType(), CName)); - PRINT_PEEPHOLE2("CL-LoadCast:out", NLI, CI); + // Replace the old store with a new one! + ReplaceInstWithInst(BB->getInstList(), BI, NCI); + PRINT_PEEPHOLE3("load-src-cast:out", NCI, CastSrc, NewLI); + ++NumLoadStorePeepholes; + return true; + } - return true; - } - } } else if (I->getOpcode() == Instruction::Add && isa(I->getOperand(1))) { if (PeepholeOptimizeAddCast(BB, BI, I->getOperand(0), - cast(I->getOperand(1)))) + cast(I->getOperand(1)))) { + ++NumGEPInstFormed; return true; + } + } else if (CallInst *CI = dyn_cast(I)) { + // If we have a call with all varargs arguments, convert the call to use the + // actual argument types present... + // + const PointerType *PTy = cast(CI->getCalledValue()->getType()); + const FunctionType *FTy = cast(PTy->getElementType()); + + // Is the call to a vararg variable with no real parameters? + if (FTy->isVarArg() && FTy->getNumParams() == 0) { + // If so, insert a new cast instruction, casting it to a function type + // that matches the current arguments... + // + std::vector Params; // Parameter types... + for (unsigned i = 1, e = CI->getNumOperands(); i != e; ++i) + Params.push_back(CI->getOperand(i)->getType()); + + FunctionType *NewFT = FunctionType::get(FTy->getReturnType(), + Params, false); + PointerType *NewPFunTy = PointerType::get(NewFT); + + // Create a new cast, inserting it right before the function call... + CastInst *NewCast = new CastInst(CI->getCalledValue(), NewPFunTy, + CI->getCalledValue()->getName(), CI); + + // Create a new call instruction... + CallInst *NewCall = new CallInst(NewCast, + std::vector(CI->op_begin()+1, CI->op_end())); + ++BI; + ReplaceInstWithInst(CI, NewCall); + + ++NumVarargCallChanges; + return true; + } -#endif } return false; @@ -763,59 +500,83 @@ static bool PeepholeOptimize(BasicBlock *BB, BasicBlock::iterator &BI) { -static bool DoRaisePass(Method *M) { +static bool DoRaisePass(Function &F) { bool Changed = false; - for (Method::iterator MI = M->begin(), ME = M->end(); MI != ME; ++MI) { - BasicBlock *BB = *MI; - BasicBlock::InstListType &BIL = BB->getInstList(); - + for (Function::iterator BB = F.begin(), BBE = F.end(); BB != BBE; ++BB) for (BasicBlock::iterator BI = BB->begin(); BI != BB->end();) { - if (opt::DeadCodeElimination::dceInstruction(BIL, BI)) { + DEBUG(cerr << "Processing: " << *BI); + if (dceInstruction(BI) || doConstantPropogation(BI)) { Changed = true; -#ifdef DEBUG_PEEPHOLE_INSTS - cerr << "DeadCode Elinated!\n"; -#endif - } else if (PeepholeOptimize(BB, BI)) + ++NumDCEorCP; + DEBUG(cerr << "***\t\t^^-- Dead code eliminated!\n"); + } else if (PeepholeOptimize(BB, BI)) { Changed = true; - else + } else { ++BI; + } } - } + return Changed; } -// RaisePointerReferences::doit - Raise a method representation to a higher +// RaisePointerReferences::doit - Raise a function representation to a higher // level. // -bool RaisePointerReferences::doit(Method *M) { - if (M->isExternal()) return false; - bool Changed = false; +static bool doRPR(Function &F) { + DEBUG(cerr << "\n\n\nStarting to work on Function '" << F.getName() << "'\n"); -#ifdef DEBUG_PEEPHOLE_INSTS - cerr << "\n\n\nStarting to work on Method '" << M->getName() << "'\n"; -#endif + // Insert casts for all incoming pointer pointer values that are treated as + // arrays... + // + bool Changed = false, LocalChange; + - while (DoRaisePass(M)) Changed = true; + // If the StartInst option was specified, then Peephole optimize that + // instruction first if it occurs in this function. + // + if (!StartInst.empty()) { + for (Function::iterator BB = F.begin(), BBE = F.end(); BB != BBE; ++BB) + for (BasicBlock::iterator BI = BB->begin(); BI != BB->end(); ++BI) + if (BI->getName() == StartInst) { + bool SavedDebug = DebugFlag; // Save the DEBUG() controlling flag. + DebugFlag = true; // Turn on DEBUG's + Changed |= PeepholeOptimize(BB, BI); + DebugFlag = SavedDebug; // Restore DebugFlag to previous state + } + } -#if 0 - // PtrCasts - Keep a mapping between the pointer values (the key of the - // map), and the cast to array pointer (the value) in this map. This is - // used when converting pointer math into array addressing. - // - map PtrCasts; + do { + DEBUG(cerr << "Looping: \n" << F); - // Insert casts for all incoming pointer values. Keep track of those casts - // and the identified incoming values in the PtrCasts map. - // - Changed |= DoInsertArrayCasts(M, PtrCasts); + // Iterate over the function, refining it, until it converges on a stable + // state + LocalChange = false; + while (DoRaisePass(F)) LocalChange = true; + Changed |= LocalChange; - // Loop over each incoming pointer variable, replacing indexing arithmetic - // with getelementptr calls. - // - Changed |= reduce_apply_bool(PtrCasts.begin(), PtrCasts.end(), - ptr_fun(DoEliminatePointerArithmetic)); -#endif + } while (LocalChange); return Changed; } + +namespace { + struct RaisePointerReferences : public FunctionPass { + + // FIXME: constructor should save and use target data here!! + RaisePointerReferences(const TargetData &TD) {} + + virtual bool runOnFunction(Function &F) { return doRPR(F); } + + virtual void getAnalysisUsage(AnalysisUsage &AU) const { + AU.preservesCFG(); + } + }; +} + +Pass *createRaisePointerReferencesPass(const TargetData &TD) { + return new RaisePointerReferences(TD); +} + +static RegisterOpt +X("raise", "Raise Pointer References", createRaisePointerReferencesPass);