/usr/include/llvm-6.0/llvm/Analysis/ConstantFolding.h is in llvm-6.0-dev 1:6.0-1ubuntu2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 | //===-- ConstantFolding.h - Fold instructions into constants ----*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file declares routines for folding instructions into constants when all
// operands are constants, for example "sub i32 1, 0" -> "1".
//
// Also, to supplement the basic VMCore ConstantExpr simplifications,
// this file declares some additional folding routines that can make use of
// DataLayout information. These functions cannot go in VMCore due to library
// dependency issues.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_ANALYSIS_CONSTANTFOLDING_H
#define LLVM_ANALYSIS_CONSTANTFOLDING_H
namespace llvm {
class APInt;
template <typename T> class ArrayRef;
class CallSite;
class Constant;
class ConstantExpr;
class ConstantVector;
class DataLayout;
class Function;
class GlobalValue;
class Instruction;
class ImmutableCallSite;
class TargetLibraryInfo;
class Type;
/// If this constant is a constant offset from a global, return the global and
/// the constant. Because of constantexprs, this function is recursive.
bool IsConstantOffsetFromGlobal(Constant *C, GlobalValue *&GV, APInt &Offset,
const DataLayout &DL);
/// ConstantFoldInstruction - Try to constant fold the specified instruction.
/// If successful, the constant result is returned, if not, null is returned.
/// Note that this fails if not all of the operands are constant. Otherwise,
/// 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 DataLayout &DL,
const TargetLibraryInfo *TLI = nullptr);
/// ConstantFoldConstant - Attempt to fold the constant using the
/// specified DataLayout.
/// If successful, the constant result is returned, if not, null is returned.
Constant *ConstantFoldConstant(const Constant *C, const DataLayout &DL,
const TargetLibraryInfo *TLI = nullptr);
/// 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(Instruction *I, ArrayRef<Constant *> Ops,
const DataLayout &DL,
const TargetLibraryInfo *TLI = nullptr);
/// 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 *LHS,
Constant *RHS, const DataLayout &DL,
const TargetLibraryInfo *TLI = nullptr);
/// \brief Attempt to constant fold a binary operation with the specified
/// operands. If it fails, it returns a constant expression of the specified
/// operands.
Constant *ConstantFoldBinaryOpOperands(unsigned Opcode, Constant *LHS,
Constant *RHS, const DataLayout &DL);
/// \brief Attempt to constant fold a select instruction with the specified
/// operands. The constant result is returned if successful; if not, null is
/// returned.
Constant *ConstantFoldSelectInstruction(Constant *Cond, Constant *V1,
Constant *V2);
/// \brief Attempt to constant fold a cast with the specified operand. If it
/// fails, it returns a constant expression of the specified operand.
Constant *ConstantFoldCastOperand(unsigned Opcode, Constant *C, Type *DestTy,
const DataLayout &DL);
/// ConstantFoldInsertValueInstruction - Attempt to constant fold an insertvalue
/// instruction with the specified operands and indices. The constant result is
/// returned if successful; if not, null is returned.
Constant *ConstantFoldInsertValueInstruction(Constant *Agg, Constant *Val,
ArrayRef<unsigned> Idxs);
/// \brief Attempt to constant fold an extractvalue instruction with the
/// specified operands and indices. The constant result is returned if
/// successful; if not, null is returned.
Constant *ConstantFoldExtractValueInstruction(Constant *Agg,
ArrayRef<unsigned> Idxs);
/// \brief Attempt to constant fold an insertelement instruction with the
/// specified operands and indices. The constant result is returned if
/// successful; if not, null is returned.
Constant *ConstantFoldInsertElementInstruction(Constant *Val,
Constant *Elt,
Constant *Idx);
/// \brief Attempt to constant fold an extractelement instruction with the
/// specified operands and indices. The constant result is returned if
/// successful; if not, null is returned.
Constant *ConstantFoldExtractElementInstruction(Constant *Val, Constant *Idx);
/// \brief Attempt to constant fold a shufflevector instruction with the
/// specified operands and indices. The constant result is returned if
/// successful; if not, null is returned.
Constant *ConstantFoldShuffleVectorInstruction(Constant *V1, Constant *V2,
Constant *Mask);
/// ConstantFoldLoadFromConstPtr - Return the value that a load from C would
/// produce if it is constant and determinable. If this is not determinable,
/// return null.
Constant *ConstantFoldLoadFromConstPtr(Constant *C, Type *Ty, const DataLayout &DL);
/// 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);
/// ConstantFoldLoadThroughGEPIndices - Given a constant and getelementptr
/// indices (with an *implied* zero pointer index that is not in the list),
/// return the constant value being addressed by a virtual load, or null if
/// something is funny and we can't decide.
Constant *ConstantFoldLoadThroughGEPIndices(Constant *C,
ArrayRef<Constant *> Indices);
/// canConstantFoldCallTo - Return true if its even possible to fold a call to
/// the specified function.
bool canConstantFoldCallTo(ImmutableCallSite CS, const Function *F);
/// ConstantFoldCall - Attempt to constant fold a call to the specified function
/// with the specified arguments, returning null if unsuccessful.
Constant *ConstantFoldCall(ImmutableCallSite CS, Function *F,
ArrayRef<Constant *> Operands,
const TargetLibraryInfo *TLI = nullptr);
/// \brief Check whether the given call has no side-effects.
/// Specifically checks for math routimes which sometimes set errno.
bool isMathLibCallNoop(CallSite CS, const TargetLibraryInfo *TLI);
}
#endif
|