| //===-- ConstantFolding.h - Analyze constant folding possibilities --------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This family of functions determines the possibility of performing constant |
| // folding. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef LLVM_ANALYSIS_CONSTANTFOLDING_H |
| #define LLVM_ANALYSIS_CONSTANTFOLDING_H |
| |
| namespace llvm { |
| class Constant; |
| class ConstantExpr; |
| class Instruction; |
| class TargetData; |
| class Function; |
| class Type; |
| class LLVMContext; |
| |
| /// ConstantFoldInstruction - Attempt to constant fold the specified |
| /// instruction. If successful, the constant result is returned, if not, null |
| /// is returned. Note that this function can only fail when attempting to fold |
| /// instructions like loads and stores, which have no constant expression form. |
| /// |
| Constant *ConstantFoldInstruction(Instruction *I, LLVMContext &Context, |
| const TargetData *TD = 0); |
| |
| /// ConstantFoldConstantExpression - Attempt to fold the constant expression |
| /// using the specified TargetData. If successful, the constant result is |
| /// result is returned, if not, null is returned. |
| Constant *ConstantFoldConstantExpression(ConstantExpr *CE, LLVMContext &Context, |
| const TargetData *TD = 0); |
| |
| /// ConstantFoldInstOperands - Attempt to constant fold an instruction with the |
| /// specified operands. If successful, the constant result is returned, if not, |
| /// null is returned. Note that this function can fail when attempting to |
| /// fold instructions like loads and stores, which have no constant expression |
| /// form. |
| /// |
| Constant *ConstantFoldInstOperands(unsigned Opcode, const Type *DestTy, |
| Constant*const * Ops, unsigned NumOps, |
| LLVMContext &Context, |
| const TargetData *TD = 0); |
| |
| /// ConstantFoldCompareInstOperands - Attempt to constant fold a compare |
| /// instruction (icmp/fcmp) with the specified operands. If it fails, it |
| /// returns a constant expression of the specified operands. |
| /// |
| Constant *ConstantFoldCompareInstOperands(unsigned Predicate, |
| Constant*const * Ops, unsigned NumOps, |
| LLVMContext &Context, |
| const TargetData *TD = 0); |
| |
| |
| /// ConstantFoldLoadThroughGEPConstantExpr - Given a constant and a |
| /// getelementptr constantexpr, return the constant value being addressed by the |
| /// constant expression, or null if something is funny and we can't decide. |
| Constant *ConstantFoldLoadThroughGEPConstantExpr(Constant *C, ConstantExpr *CE, |
| LLVMContext &Context); |
| |
| /// canConstantFoldCallTo - Return true if its even possible to fold a call to |
| /// the specified function. |
| bool canConstantFoldCallTo(const Function *F); |
| |
| /// ConstantFoldCall - Attempt to constant fold a call to the specified function |
| /// with the specified arguments, returning null if unsuccessful. |
| Constant * |
| ConstantFoldCall(Function *F, Constant* const* Operands, unsigned NumOperands); |
| } |
| |
| #endif |