1 //===-- InstructionSimplify.h - Fold instructions into simpler forms ------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
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.
17 //===----------------------------------------------------------------------===//
19 #ifndef LLVM_ANALYSIS_INSTRUCTIONSIMPLIFY_H
20 #define LLVM_ANALYSIS_INSTRUCTIONSIMPLIFY_H
29 class TargetLibraryInfo;
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);
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);
47 /// Given operands for an FAdd, see if we can fold the result. If not, this
49 Value *SimplifyFAddInst(Value *LHS, Value *RHS, FastMathFlags FMF,
50 const DataLayout *TD = 0,
51 const TargetLibraryInfo *TLI = 0,
52 const DominatorTree *DT = 0);
54 /// Given operands for an FSub, see if we can fold the result. If not, this
56 Value *SimplifyFSubInst(Value *LHS, Value *RHS, FastMathFlags FMF,
57 const DataLayout *TD = 0,
58 const TargetLibraryInfo *TLI = 0,
59 const DominatorTree *DT = 0);
61 /// Given operands for an FMul, see if we can fold the result. If not, this
63 Value *SimplifyFMulInst(Value *LHS, Value *RHS,
65 const DataLayout *TD = 0,
66 const TargetLibraryInfo *TLI = 0,
67 const DominatorTree *DT = 0);
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);
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);
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);
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);
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);
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);
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);
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);
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);
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);
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);
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);
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);
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);
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);
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);
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);
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);
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);
191 //=== Helper functions for higher up the class hierarchy.
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);
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);
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);
215 /// \brief Replace all uses of 'I' with 'SimpleV' and simplify the uses
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'.
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);
228 /// \brief Recursively attempt to simplify an instruction.
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
234 bool recursivelySimplifyInstruction(Instruction *I,
235 const DataLayout *TD = 0,
236 const TargetLibraryInfo *TLI = 0,
237 const DominatorTree *DT = 0);
238 } // end namespace llvm