1 //===-- Float2Int.h - Demote floating point ops to work on integers -------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file provides the Float2Int pass, which aims to demote floating
10 // point operations to work on integers, where that is losslessly possible.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #ifndef LLVM_TRANSFORMS_SCALAR_FLOAT2INT_H
15 #define LLVM_TRANSFORMS_SCALAR_FLOAT2INT_H
16 
17 #include "llvm/ADT/EquivalenceClasses.h"
18 #include "llvm/ADT/MapVector.h"
19 #include "llvm/ADT/SetVector.h"
20 #include "llvm/IR/ConstantRange.h"
21 #include "llvm/IR/PassManager.h"
22 
23 namespace llvm {
24 class DominatorTree;
25 class Function;
26 class Instruction;
27 class LLVMContext;
28 class Type;
29 class Value;
30 
31 class Float2IntPass : public PassInfoMixin<Float2IntPass> {
32 public:
33   PreservedAnalyses run(Function &F, FunctionAnalysisManager &AM);
34 
35   // Glue for old PM.
36   bool runImpl(Function &F, const DominatorTree &DT);
37 
38 private:
39   void findRoots(Function &F, const DominatorTree &DT);
40   void seen(Instruction *I, ConstantRange R);
41   ConstantRange badRange();
42   ConstantRange unknownRange();
43   ConstantRange validateRange(ConstantRange R);
44   std::optional<ConstantRange> calcRange(Instruction *I);
45   void walkBackwards();
46   void walkForwards();
47   bool validateAndTransform();
48   Value *convert(Instruction *I, Type *ToTy);
49   void cleanup();
50 
51   MapVector<Instruction *, ConstantRange> SeenInsts;
52   SmallSetVector<Instruction *, 8> Roots;
53   EquivalenceClasses<Instruction *> ECs;
54   MapVector<Instruction *, Value *> ConvertedInsts;
55   LLVMContext *Ctx;
56 };
57 }
58 #endif // LLVM_TRANSFORMS_SCALAR_FLOAT2INT_H
59