| //===- GISelWorkList.h - Worklist for GISel passes ----*- C++ -*-===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef LLVM_GISEL_WORKLIST_H |
| #define LLVM_GISEL_WORKLIST_H |
| |
| #include "llvm/ADT/DenseMap.h" |
| #include "llvm/ADT/SmallVector.h" |
| #include "llvm/Support/Debug.h" |
| |
| namespace llvm { |
| |
| class MachineInstr; |
| |
| // Worklist which mostly works similar to InstCombineWorkList, but on MachineInstrs. |
| // The main difference with something like a SetVector is that erasing an element doesn't |
| // move all elements over one place - instead just nulls out the element of the vector. |
| // FIXME: Does it make sense to factor out common code with the instcombinerWorkList? |
| template<unsigned N> |
| class GISelWorkList { |
| SmallVector<MachineInstr*, N> Worklist; |
| DenseMap<MachineInstr*, unsigned> WorklistMap; |
| |
| public: |
| GISelWorkList() = default; |
| |
| bool empty() const { return WorklistMap.empty(); } |
| |
| unsigned size() const { return WorklistMap.size(); } |
| |
| /// Add - Add the specified instruction to the worklist if it isn't already |
| /// in it. |
| void insert(MachineInstr *I) { |
| if (WorklistMap.try_emplace(I, Worklist.size()).second) { |
| Worklist.push_back(I); |
| } |
| } |
| |
| /// Remove - remove I from the worklist if it exists. |
| void remove(MachineInstr *I) { |
| auto It = WorklistMap.find(I); |
| if (It == WorklistMap.end()) return; // Not in worklist. |
| |
| // Don't bother moving everything down, just null out the slot. |
| Worklist[It->second] = nullptr; |
| |
| WorklistMap.erase(It); |
| } |
| |
| MachineInstr *pop_back_val() { |
| MachineInstr *I; |
| do { |
| I = Worklist.pop_back_val(); |
| } while(!I); |
| assert(I && "Pop back on empty worklist"); |
| WorklistMap.erase(I); |
| return I; |
| } |
| }; |
| |
| } // end namespace llvm. |
| |
| #endif |