1//===-- InstructionSimplify.h - Fold instructions into simpler forms ------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file declares routines for folding instructions into simpler forms 11// that do not require creating new instructions. This does constant folding 12// ("add i32 1, 1" -> "2") but can also handle non-constant operands, either 13// returning a constant ("and i32 %x, 0" -> "0") or an already existing value 14// ("and i32 %x, %x" -> "%x"). If the simplification is also an instruction 15// then it dominates the original instruction. 16// 17//===----------------------------------------------------------------------===// 18 19#ifndef LLVM_ANALYSIS_INSTRUCTIONSIMPLIFY_H 20#define LLVM_ANALYSIS_INSTRUCTIONSIMPLIFY_H 21 22namespace llvm { 23 template<typename T> 24 class ArrayRef; 25 class DominatorTree; 26 class Instruction; 27 class TargetData; 28 class TargetLibraryInfo; 29 class Type; 30 class Value; 31 32 /// SimplifyAddInst - Given operands for an Add, see if we can 33 /// fold the result. If not, this returns null. 34 Value *SimplifyAddInst(Value *LHS, Value *RHS, bool isNSW, bool isNUW, 35 const TargetData *TD = 0, 36 const TargetLibraryInfo *TLI = 0, 37 const DominatorTree *DT = 0); 38 39 /// SimplifySubInst - Given operands for a Sub, see if we can 40 /// fold the result. If not, this returns null. 41 Value *SimplifySubInst(Value *LHS, Value *RHS, bool isNSW, bool isNUW, 42 const TargetData *TD = 0, 43 const TargetLibraryInfo *TLI = 0, 44 const DominatorTree *DT = 0); 45 46 /// SimplifyMulInst - Given operands for a Mul, see if we can 47 /// fold the result. If not, this returns null. 48 Value *SimplifyMulInst(Value *LHS, Value *RHS, const TargetData *TD = 0, 49 const TargetLibraryInfo *TLI = 0, 50 const DominatorTree *DT = 0); 51 52 /// SimplifySDivInst - Given operands for an SDiv, see if we can 53 /// fold the result. If not, this returns null. 54 Value *SimplifySDivInst(Value *LHS, Value *RHS, const TargetData *TD = 0, 55 const TargetLibraryInfo *TLI = 0, 56 const DominatorTree *DT = 0); 57 58 /// SimplifyUDivInst - Given operands for a UDiv, see if we can 59 /// fold the result. If not, this returns null. 60 Value *SimplifyUDivInst(Value *LHS, Value *RHS, const TargetData *TD = 0, 61 const TargetLibraryInfo *TLI = 0, 62 const DominatorTree *DT = 0); 63 64 /// SimplifyFDivInst - Given operands for an FDiv, see if we can 65 /// fold the result. If not, this returns null. 66 Value *SimplifyFDivInst(Value *LHS, Value *RHS, const TargetData *TD = 0, 67 const TargetLibraryInfo *TLI = 0, 68 const DominatorTree *DT = 0); 69 70 /// SimplifySRemInst - Given operands for an SRem, see if we can 71 /// fold the result. If not, this returns null. 72 Value *SimplifySRemInst(Value *LHS, Value *RHS, const TargetData *TD = 0, 73 const TargetLibraryInfo *TLI = 0, 74 const DominatorTree *DT = 0); 75 76 /// SimplifyURemInst - Given operands for a URem, see if we can 77 /// fold the result. If not, this returns null. 78 Value *SimplifyURemInst(Value *LHS, Value *RHS, const TargetData *TD = 0, 79 const TargetLibraryInfo *TLI = 0, 80 const DominatorTree *DT = 0); 81 82 /// SimplifyFRemInst - Given operands for an FRem, see if we can 83 /// fold the result. If not, this returns null. 84 Value *SimplifyFRemInst(Value *LHS, Value *RHS, const TargetData *TD = 0, 85 const TargetLibraryInfo *TLI = 0, 86 const DominatorTree *DT = 0); 87 88 /// SimplifyShlInst - Given operands for a Shl, see if we can 89 /// fold the result. If not, this returns null. 90 Value *SimplifyShlInst(Value *Op0, Value *Op1, bool isNSW, bool isNUW, 91 const TargetData *TD = 0, 92 const TargetLibraryInfo *TLI = 0, 93 const DominatorTree *DT = 0); 94 95 /// SimplifyLShrInst - Given operands for a LShr, see if we can 96 /// fold the result. If not, this returns null. 97 Value *SimplifyLShrInst(Value *Op0, Value *Op1, bool isExact, 98 const TargetData *TD = 0, 99 const TargetLibraryInfo *TLI = 0, 100 const DominatorTree *DT = 0); 101 102 /// SimplifyAShrInst - Given operands for a AShr, see if we can 103 /// fold the result. If not, this returns null. 104 Value *SimplifyAShrInst(Value *Op0, Value *Op1, bool isExact, 105 const TargetData *TD = 0, 106 const TargetLibraryInfo *TLI = 0, 107 const DominatorTree *DT = 0); 108 109 /// SimplifyAndInst - Given operands for an And, see if we can 110 /// fold the result. If not, this returns null. 111 Value *SimplifyAndInst(Value *LHS, Value *RHS, const TargetData *TD = 0, 112 const TargetLibraryInfo *TLI = 0, 113 const DominatorTree *DT = 0); 114 115 /// SimplifyOrInst - Given operands for an Or, see if we can 116 /// fold the result. If not, this returns null. 117 Value *SimplifyOrInst(Value *LHS, Value *RHS, const TargetData *TD = 0, 118 const TargetLibraryInfo *TLI = 0, 119 const DominatorTree *DT = 0); 120 121 /// SimplifyXorInst - Given operands for a Xor, see if we can 122 /// fold the result. If not, this returns null. 123 Value *SimplifyXorInst(Value *LHS, Value *RHS, const TargetData *TD = 0, 124 const TargetLibraryInfo *TLI = 0, 125 const DominatorTree *DT = 0); 126 127 /// SimplifyICmpInst - Given operands for an ICmpInst, see if we can 128 /// fold the result. If not, this returns null. 129 Value *SimplifyICmpInst(unsigned Predicate, Value *LHS, Value *RHS, 130 const TargetData *TD = 0, 131 const TargetLibraryInfo *TLI = 0, 132 const DominatorTree *DT = 0); 133 134 /// SimplifyFCmpInst - Given operands for an FCmpInst, see if we can 135 /// fold the result. If not, this returns null. 136 Value *SimplifyFCmpInst(unsigned Predicate, Value *LHS, Value *RHS, 137 const TargetData *TD = 0, 138 const TargetLibraryInfo *TLI = 0, 139 const DominatorTree *DT = 0); 140 141 /// SimplifySelectInst - Given operands for a SelectInst, see if we can fold 142 /// the result. If not, this returns null. 143 Value *SimplifySelectInst(Value *Cond, Value *TrueVal, Value *FalseVal, 144 const TargetData *TD = 0, 145 const TargetLibraryInfo *TLI = 0, 146 const DominatorTree *DT = 0); 147 148 /// SimplifyGEPInst - Given operands for an GetElementPtrInst, see if we can 149 /// fold the result. If not, this returns null. 150 Value *SimplifyGEPInst(ArrayRef<Value *> Ops, const TargetData *TD = 0, 151 const TargetLibraryInfo *TLI = 0, 152 const DominatorTree *DT = 0); 153 154 /// SimplifyInsertValueInst - Given operands for an InsertValueInst, see if we 155 /// can fold the result. If not, this returns null. 156 Value *SimplifyInsertValueInst(Value *Agg, Value *Val, 157 ArrayRef<unsigned> Idxs, 158 const TargetData *TD = 0, 159 const TargetLibraryInfo *TLI = 0, 160 const DominatorTree *DT = 0); 161 162 /// SimplifyTruncInst - Given operands for an TruncInst, see if we can fold 163 /// the result. If not, this returns null. 164 Value *SimplifyTruncInst(Value *Op, Type *Ty, const TargetData *TD = 0, 165 const TargetLibraryInfo *TLI = 0, 166 const DominatorTree *DT = 0); 167 168 //=== Helper functions for higher up the class hierarchy. 169 170 171 /// SimplifyCmpInst - Given operands for a CmpInst, see if we can 172 /// fold the result. If not, this returns null. 173 Value *SimplifyCmpInst(unsigned Predicate, Value *LHS, Value *RHS, 174 const TargetData *TD = 0, 175 const TargetLibraryInfo *TLI = 0, 176 const DominatorTree *DT = 0); 177 178 /// SimplifyBinOp - Given operands for a BinaryOperator, see if we can 179 /// fold the result. If not, this returns null. 180 Value *SimplifyBinOp(unsigned Opcode, Value *LHS, Value *RHS, 181 const TargetData *TD = 0, 182 const TargetLibraryInfo *TLI = 0, 183 const DominatorTree *DT = 0); 184 185 /// SimplifyInstruction - See if we can compute a simplified version of this 186 /// instruction. If not, this returns null. 187 Value *SimplifyInstruction(Instruction *I, const TargetData *TD = 0, 188 const TargetLibraryInfo *TLI = 0, 189 const DominatorTree *DT = 0); 190 191 192 /// \brief Replace all uses of 'I' with 'SimpleV' and simplify the uses 193 /// recursively. 194 /// 195 /// This first performs a normal RAUW of I with SimpleV. It then recursively 196 /// attempts to simplify those users updated by the operation. The 'I' 197 /// instruction must not be equal to the simplified value 'SimpleV'. 198 /// 199 /// The function returns true if any simplifications were performed. 200 bool replaceAndRecursivelySimplify(Instruction *I, Value *SimpleV, 201 const TargetData *TD = 0, 202 const TargetLibraryInfo *TLI = 0, 203 const DominatorTree *DT = 0); 204 205 /// \brief Recursively attempt to simplify an instruction. 206 /// 207 /// This routine uses SimplifyInstruction to simplify 'I', and if successful 208 /// replaces uses of 'I' with the simplified value. It then recurses on each 209 /// of the users impacted. It returns true if any simplifications were 210 /// performed. 211 bool recursivelySimplifyInstruction(Instruction *I, 212 const TargetData *TD = 0, 213 const TargetLibraryInfo *TLI = 0, 214 const DominatorTree *DT = 0); 215} // end namespace llvm 216 217#endif 218 219