InstructionSimplify.h revision 09ee250e728ccdb7afc6354d777f8319c5a0465c
19720d5f59b9c1f5d1b9ecbc9173dbcb71bd557beSteve Block//===-- InstructionSimplify.h - Fold instructions into simpler forms ------===// 29720d5f59b9c1f5d1b9ecbc9173dbcb71bd557beSteve Block// 39720d5f59b9c1f5d1b9ecbc9173dbcb71bd557beSteve Block// The LLVM Compiler Infrastructure 49720d5f59b9c1f5d1b9ecbc9173dbcb71bd557beSteve Block// 59720d5f59b9c1f5d1b9ecbc9173dbcb71bd557beSteve Block// This file is distributed under the University of Illinois Open Source 69720d5f59b9c1f5d1b9ecbc9173dbcb71bd557beSteve Block// License. See LICENSE.TXT for details. 79720d5f59b9c1f5d1b9ecbc9173dbcb71bd557beSteve Block// 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 DataLayout; 28 class FastMathFlags; 29 class TargetLibraryInfo; 30 class Type; 31 class Value; 32 33 /// SimplifyAddInst - Given operands for an Add, see if we can 34 /// fold the result. If not, this returns null. 35 Value *SimplifyAddInst(Value *LHS, Value *RHS, bool isNSW, bool isNUW, 36 const DataLayout *TD = 0, 37 const TargetLibraryInfo *TLI = 0, 38 const DominatorTree *DT = 0); 39 40 /// SimplifySubInst - Given operands for a Sub, see if we can 41 /// fold the result. If not, this returns null. 42 Value *SimplifySubInst(Value *LHS, Value *RHS, bool isNSW, bool isNUW, 43 const DataLayout *TD = 0, 44 const TargetLibraryInfo *TLI = 0, 45 const DominatorTree *DT = 0); 46 47 /// Given operands for an FAdd, see if we can fold the result. If not, this 48 /// returns null. 49 Value *SimplifyFAddInst(Value *LHS, Value *RHS, FastMathFlags FMF, 50 const DataLayout *TD = 0, 51 const TargetLibraryInfo *TLI = 0, 52 const DominatorTree *DT = 0); 53 54 /// Given operands for an FSub, see if we can fold the result. If not, this 55 /// returns null. 56 Value *SimplifyFSubInst(Value *LHS, Value *RHS, FastMathFlags FMF, 57 const DataLayout *TD = 0, 58 const TargetLibraryInfo *TLI = 0, 59 const DominatorTree *DT = 0); 60 61 /// Given operands for an FMul, see if we can fold the result. If not, this 62 /// returns null. 63 Value *SimplifyFMulInst(Value *LHS, Value *RHS, 64 FastMathFlags FMF, 65 const DataLayout *TD = 0, 66 const TargetLibraryInfo *TLI = 0, 67 const DominatorTree *DT = 0); 68 69 /// SimplifyMulInst - Given operands for a Mul, see if we can 70 /// fold the result. If not, this returns null. 71 Value *SimplifyMulInst(Value *LHS, Value *RHS, const DataLayout *TD = 0, 72 const TargetLibraryInfo *TLI = 0, 73 const DominatorTree *DT = 0); 74 75 /// SimplifySDivInst - Given operands for an SDiv, see if we can 76 /// fold the result. If not, this returns null. 77 Value *SimplifySDivInst(Value *LHS, Value *RHS, const DataLayout *TD = 0, 78 const TargetLibraryInfo *TLI = 0, 79 const DominatorTree *DT = 0); 80 81 /// SimplifyUDivInst - Given operands for a UDiv, see if we can 82 /// fold the result. If not, this returns null. 83 Value *SimplifyUDivInst(Value *LHS, Value *RHS, const DataLayout *TD = 0, 84 const TargetLibraryInfo *TLI = 0, 85 const DominatorTree *DT = 0); 86 87 /// SimplifyFDivInst - Given operands for an FDiv, see if we can 88 /// fold the result. If not, this returns null. 89 Value *SimplifyFDivInst(Value *LHS, Value *RHS, const DataLayout *TD = 0, 90 const TargetLibraryInfo *TLI = 0, 91 const DominatorTree *DT = 0); 92 93 /// SimplifySRemInst - Given operands for an SRem, see if we can 94 /// fold the result. If not, this returns null. 95 Value *SimplifySRemInst(Value *LHS, Value *RHS, const DataLayout *TD = 0, 96 const TargetLibraryInfo *TLI = 0, 97 const DominatorTree *DT = 0); 98 99 /// SimplifyURemInst - Given operands for a URem, see if we can 100 /// fold the result. If not, this returns null. 101 Value *SimplifyURemInst(Value *LHS, Value *RHS, const DataLayout *TD = 0, 102 const TargetLibraryInfo *TLI = 0, 103 const DominatorTree *DT = 0); 104 105 /// SimplifyFRemInst - Given operands for an FRem, see if we can 106 /// fold the result. If not, this returns null. 107 Value *SimplifyFRemInst(Value *LHS, Value *RHS, const DataLayout *TD = 0, 108 const TargetLibraryInfo *TLI = 0, 109 const DominatorTree *DT = 0); 110 111 /// SimplifyShlInst - Given operands for a Shl, see if we can 112 /// fold the result. If not, this returns null. 113 Value *SimplifyShlInst(Value *Op0, Value *Op1, bool isNSW, bool isNUW, 114 const DataLayout *TD = 0, 115 const TargetLibraryInfo *TLI = 0, 116 const DominatorTree *DT = 0); 117 118 /// SimplifyLShrInst - Given operands for a LShr, see if we can 119 /// fold the result. If not, this returns null. 120 Value *SimplifyLShrInst(Value *Op0, Value *Op1, bool isExact, 121 const DataLayout *TD = 0, 122 const TargetLibraryInfo *TLI = 0, 123 const DominatorTree *DT = 0); 124 125 /// SimplifyAShrInst - Given operands for a AShr, see if we can 126 /// fold the result. If not, this returns null. 127 Value *SimplifyAShrInst(Value *Op0, Value *Op1, bool isExact, 128 const DataLayout *TD = 0, 129 const TargetLibraryInfo *TLI = 0, 130 const DominatorTree *DT = 0); 131 132 /// SimplifyAndInst - Given operands for an And, see if we can 133 /// fold the result. If not, this returns null. 134 Value *SimplifyAndInst(Value *LHS, Value *RHS, const DataLayout *TD = 0, 135 const TargetLibraryInfo *TLI = 0, 136 const DominatorTree *DT = 0); 137 138 /// SimplifyOrInst - Given operands for an Or, see if we can 139 /// fold the result. If not, this returns null. 140 Value *SimplifyOrInst(Value *LHS, Value *RHS, const DataLayout *TD = 0, 141 const TargetLibraryInfo *TLI = 0, 142 const DominatorTree *DT = 0); 143 144 /// SimplifyXorInst - Given operands for a Xor, see if we can 145 /// fold the result. If not, this returns null. 146 Value *SimplifyXorInst(Value *LHS, Value *RHS, const DataLayout *TD = 0, 147 const TargetLibraryInfo *TLI = 0, 148 const DominatorTree *DT = 0); 149 150 /// SimplifyICmpInst - Given operands for an ICmpInst, see if we can 151 /// fold the result. If not, this returns null. 152 Value *SimplifyICmpInst(unsigned Predicate, Value *LHS, Value *RHS, 153 const DataLayout *TD = 0, 154 const TargetLibraryInfo *TLI = 0, 155 const DominatorTree *DT = 0); 156 157 /// SimplifyFCmpInst - Given operands for an FCmpInst, see if we can 158 /// fold the result. If not, this returns null. 159 Value *SimplifyFCmpInst(unsigned Predicate, Value *LHS, Value *RHS, 160 const DataLayout *TD = 0, 161 const TargetLibraryInfo *TLI = 0, 162 const DominatorTree *DT = 0); 163 164 /// SimplifySelectInst - Given operands for a SelectInst, see if we can fold 165 /// the result. If not, this returns null. 166 Value *SimplifySelectInst(Value *Cond, Value *TrueVal, Value *FalseVal, 167 const DataLayout *TD = 0, 168 const TargetLibraryInfo *TLI = 0, 169 const DominatorTree *DT = 0); 170 171 /// SimplifyGEPInst - Given operands for an GetElementPtrInst, see if we can 172 /// fold the result. If not, this returns null. 173 Value *SimplifyGEPInst(ArrayRef<Value *> Ops, const DataLayout *TD = 0, 174 const TargetLibraryInfo *TLI = 0, 175 const DominatorTree *DT = 0); 176 177 /// SimplifyInsertValueInst - Given operands for an InsertValueInst, see if we 178 /// can fold the result. If not, this returns null. 179 Value *SimplifyInsertValueInst(Value *Agg, Value *Val, 180 ArrayRef<unsigned> Idxs, 181 const DataLayout *TD = 0, 182 const TargetLibraryInfo *TLI = 0, 183 const DominatorTree *DT = 0); 184 185 /// SimplifyTruncInst - Given operands for an TruncInst, see if we can fold 186 /// the result. If not, this returns null. 187 Value *SimplifyTruncInst(Value *Op, Type *Ty, const DataLayout *TD = 0, 188 const TargetLibraryInfo *TLI = 0, 189 const DominatorTree *DT = 0); 190 191 //=== Helper functions for higher up the class hierarchy. 192 193 194 /// SimplifyCmpInst - Given operands for a CmpInst, see if we can 195 /// fold the result. If not, this returns null. 196 Value *SimplifyCmpInst(unsigned Predicate, Value *LHS, Value *RHS, 197 const DataLayout *TD = 0, 198 const TargetLibraryInfo *TLI = 0, 199 const DominatorTree *DT = 0); 200 201 /// SimplifyBinOp - Given operands for a BinaryOperator, see if we can 202 /// fold the result. If not, this returns null. 203 Value *SimplifyBinOp(unsigned Opcode, Value *LHS, Value *RHS, 204 const DataLayout *TD = 0, 205 const TargetLibraryInfo *TLI = 0, 206 const DominatorTree *DT = 0); 207 208 /// SimplifyInstruction - See if we can compute a simplified version of this 209 /// instruction. If not, this returns null. 210 Value *SimplifyInstruction(Instruction *I, const DataLayout *TD = 0, 211 const TargetLibraryInfo *TLI = 0, 212 const DominatorTree *DT = 0); 213 214 215 /// \brief Replace all uses of 'I' with 'SimpleV' and simplify the uses 216 /// recursively. 217 /// 218 /// This first performs a normal RAUW of I with SimpleV. It then recursively 219 /// attempts to simplify those users updated by the operation. The 'I' 220 /// instruction must not be equal to the simplified value 'SimpleV'. 221 /// 222 /// The function returns true if any simplifications were performed. 223 bool replaceAndRecursivelySimplify(Instruction *I, Value *SimpleV, 224 const DataLayout *TD = 0, 225 const TargetLibraryInfo *TLI = 0, 226 const DominatorTree *DT = 0); 227 228 /// \brief Recursively attempt to simplify an instruction. 229 /// 230 /// This routine uses SimplifyInstruction to simplify 'I', and if successful 231 /// replaces uses of 'I' with the simplified value. It then recurses on each 232 /// of the users impacted. It returns true if any simplifications were 233 /// performed. 234 bool recursivelySimplifyInstruction(Instruction *I, 235 const DataLayout *TD = 0, 236 const TargetLibraryInfo *TLI = 0, 237 const DominatorTree *DT = 0); 238} // end namespace llvm 239 240#endif 241 242