From: Dan Gohman Date: Sat, 21 Jun 2008 18:35:25 +0000 (+0000) Subject: Add a priority queue class, which is a wrapper around std::priority_queue X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=3627e34486db088661bc7fb6c0dde6a18a543217;p=oota-llvm.git Add a priority queue class, which is a wrapper around std::priority_queue and provides fairly efficient removal of arbitrary elements. Switch ScheduleDAGRRList from std::set to this new priority queue. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52582 91177308-0d34-0410-b5e6-96231b3b80d8 --- diff --git a/include/llvm/ADT/PriorityQueue.h b/include/llvm/ADT/PriorityQueue.h new file mode 100644 index 00000000000..1cff0f2a0ce --- /dev/null +++ b/include/llvm/ADT/PriorityQueue.h @@ -0,0 +1,77 @@ +//===- llvm/ADT/PriorityQueue.h - Priority queues ---------------*- C++ -*-===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This file defines the PriorityQueue class. +// +//===----------------------------------------------------------------------===// + +#ifndef LLVM_ADT_PRIORITY_QUEUE_H +#define LLVM_ADT_PRIORITY_QUEUE_H + +#include + +namespace llvm { + +/// PriorityQueue - This class behaves like std::priority_queue and +/// provides a few additional convenience functions. +/// +template, + class Compare = std::less > +class PriorityQueue : public std::priority_queue { +public: + explicit PriorityQueue(const Compare &compare = Compare(), + const Sequence &sequence = Sequence()) + : std::priority_queue(compare, sequence) + {} + + template + PriorityQueue(Iterator begin, Iterator end, + const Compare &compare = Compare(), + const Sequence &sequence = Sequence()) + : std::priority_queue(begin, end, compare, sequence) + {} + + /// erase_one - Erase one element from the queue, regardless of its + /// position. This operation performs a linear search to find an element + /// equal to t, but then uses all logarithmic-time algorithms to do + /// the erase operation. + /// + void erase_one(const T &t) { + // Linear-search to find the element. + typename Sequence::size_type i = + std::find(this->c.begin(), this->c.end(), t) - this->c.begin(); + + // Logarithmic-time heap bubble-up. + while (i != 0) { + typename Sequence::size_type parent = (i - 1) / 2; + std::swap(this->c[i], this->c[parent]); + i = parent; + } + + // The element we want to remove is now at the root, so we can use + // priority_queue's plain pop to remove it. + this->pop(); + } + + /// reheapify - If an element in the queue has changed in a way that + /// affects its standing in the comparison function, the queue's + /// internal state becomes invalid. Calling reheapify() resets the + /// queue's state, making it valid again. This operation has time + /// complexity proportional to the number of elements in the queue, + /// so don't plan to use it a lot. + /// + void reheapify() { + std::make_heap(this->c.begin(), this->c.end(), this->comp); + } +}; + +} // End llvm namespace + +#endif diff --git a/include/llvm/CodeGen/ScheduleDAG.h b/include/llvm/CodeGen/ScheduleDAG.h index 18aa97a9694..e032df89018 100644 --- a/include/llvm/CodeGen/ScheduleDAG.h +++ b/include/llvm/CodeGen/ScheduleDAG.h @@ -17,7 +17,6 @@ #include "llvm/CodeGen/MachineBasicBlock.h" #include "llvm/CodeGen/SelectionDAG.h" -#include "llvm/ADT/BitVector.h" #include "llvm/ADT/DenseMap.h" #include "llvm/ADT/GraphTraits.h" #include "llvm/ADT/SmallSet.h" diff --git a/lib/CodeGen/SelectionDAG/ScheduleDAG.cpp b/lib/CodeGen/SelectionDAG/ScheduleDAG.cpp index d61a0982c32..f144b986604 100644 --- a/lib/CodeGen/SelectionDAG/ScheduleDAG.cpp +++ b/lib/CodeGen/SelectionDAG/ScheduleDAG.cpp @@ -14,7 +14,6 @@ //===----------------------------------------------------------------------===// #define DEBUG_TYPE "pre-RA-sched" -#include "llvm/Constants.h" #include "llvm/Type.h" #include "llvm/CodeGen/ScheduleDAG.h" #include "llvm/CodeGen/MachineConstantPool.h" diff --git a/lib/CodeGen/SelectionDAG/ScheduleDAGRRList.cpp b/lib/CodeGen/SelectionDAG/ScheduleDAGRRList.cpp index f07bcd5fb10..99a5537f13a 100644 --- a/lib/CodeGen/SelectionDAG/ScheduleDAGRRList.cpp +++ b/lib/CodeGen/SelectionDAG/ScheduleDAGRRList.cpp @@ -24,12 +24,13 @@ #include "llvm/Target/TargetInstrInfo.h" #include "llvm/Support/Debug.h" #include "llvm/Support/Compiler.h" +#include "llvm/ADT/BitVector.h" +#include "llvm/ADT/PriorityQueue.h" #include "llvm/ADT/SmallPtrSet.h" #include "llvm/ADT/SmallSet.h" #include "llvm/ADT/Statistic.h" #include "llvm/ADT/STLExtras.h" #include -#include #include "llvm/Support/CommandLine.h" using namespace llvm; @@ -1276,7 +1277,7 @@ namespace { template class VISIBILITY_HIDDEN RegReductionPriorityQueue : public SchedulingPriorityQueue { - std::set Queue; + PriorityQueue, SF> Queue; unsigned currentQueueId; public: @@ -1303,7 +1304,7 @@ namespace { void push(SUnit *U) { assert(!U->NodeQueueId && "Node in the queue already"); U->NodeQueueId = ++currentQueueId; - Queue.insert(U); + Queue.push(U); } void push_all(const std::vector &Nodes) { @@ -1313,19 +1314,16 @@ namespace { SUnit *pop() { if (empty()) return NULL; - typename std::set::iterator i = prior(Queue.end()); - SUnit *V = *i; - Queue.erase(i); + SUnit *V = Queue.top(); + Queue.pop(); V->NodeQueueId = 0; return V; } void remove(SUnit *SU) { assert(!Queue.empty() && "Queue is empty!"); - size_t RemovedNum = Queue.erase(SU); - RemovedNum = RemovedNum; // Silence compiler warning. - assert(RemovedNum > 0 && "Not in queue!"); - assert(RemovedNum == 1 && "Multiple times in the queue!"); + assert(SU->NodeQueueId != 0 && "Not in queue!"); + Queue.erase_one(SU); SU->NodeQueueId = 0; } };