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Diffstat (limited to 'include/llvm/Analysis/ConstantFolding.h')
-rw-r--r-- | include/llvm/Analysis/ConstantFolding.h | 73 |
1 files changed, 73 insertions, 0 deletions
diff --git a/include/llvm/Analysis/ConstantFolding.h b/include/llvm/Analysis/ConstantFolding.h new file mode 100644 index 0000000..bf360f7 --- /dev/null +++ b/include/llvm/Analysis/ConstantFolding.h @@ -0,0 +1,73 @@ +//===-- 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; + +/// 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, 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, + const TargetData *TD); + +/// 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, + 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, + 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); + +/// 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 |