1 //===- InstCombineWorklist.h - Worklist for the InstCombine pass ----------===//
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 #ifndef INSTCOMBINE_WORKLIST_H
11 #define INSTCOMBINE_WORKLIST_H
13 #define DEBUG_TYPE "instcombine"
14 #include "llvm/Instruction.h"
15 #include "llvm/Support/Debug.h"
16 #include "llvm/Support/Compiler.h"
17 #include "llvm/ADT/SmallVector.h"
18 #include "llvm/ADT/DenseMap.h"
19 #include "llvm/Support/raw_ostream.h"
23 /// InstCombineWorklist - This is the worklist management logic for
25 class LLVM_LIBRARY_VISIBILITY InstCombineWorklist {
26 SmallVector<Instruction*, 256> Worklist;
27 DenseMap<Instruction*, unsigned> WorklistMap;
29 void operator=(const InstCombineWorklist&RHS); // DO NOT IMPLEMENT
30 InstCombineWorklist(const InstCombineWorklist&); // DO NOT IMPLEMENT
32 InstCombineWorklist() {}
34 bool isEmpty() const { return Worklist.empty(); }
36 /// Add - Add the specified instruction to the worklist if it isn't already
38 void Add(Instruction *I) {
39 if (WorklistMap.insert(std::make_pair(I, Worklist.size())).second) {
40 DEBUG(errs() << "IC: ADD: " << *I << '\n');
41 Worklist.push_back(I);
45 void AddValue(Value *V) {
46 if (Instruction *I = dyn_cast<Instruction>(V))
50 /// AddInitialGroup - Add the specified batch of stuff in reverse order.
51 /// which should only be done when the worklist is empty and when the group
52 /// has no duplicates.
53 void AddInitialGroup(Instruction *const *List, unsigned NumEntries) {
54 assert(Worklist.empty() && "Worklist must be empty to add initial group");
55 Worklist.reserve(NumEntries+16);
56 DEBUG(errs() << "IC: ADDING: " << NumEntries << " instrs to worklist\n");
57 for (; NumEntries; --NumEntries) {
58 Instruction *I = List[NumEntries-1];
59 WorklistMap.insert(std::make_pair(I, Worklist.size()));
60 Worklist.push_back(I);
64 // Remove - remove I from the worklist if it exists.
65 void Remove(Instruction *I) {
66 DenseMap<Instruction*, unsigned>::iterator It = WorklistMap.find(I);
67 if (It == WorklistMap.end()) return; // Not in worklist.
69 // Don't bother moving everything down, just null out the slot.
70 Worklist[It->second] = 0;
72 WorklistMap.erase(It);
75 Instruction *RemoveOne() {
76 Instruction *I = Worklist.back();
82 /// AddUsersToWorkList - When an instruction is simplified, add all users of
83 /// the instruction to the work lists because they might get more simplified
86 void AddUsersToWorkList(Instruction &I) {
87 for (Value::use_iterator UI = I.use_begin(), UE = I.use_end();
89 Add(cast<Instruction>(*UI));
93 /// Zap - check that the worklist is empty and nuke the backing store for
94 /// the map if it is large.
96 assert(WorklistMap.empty() && "Worklist empty, but map not?");
98 // Do an explicit clear, this shrinks the map if needed.
103 } // end namespace llvm.