2003-11-20 03:32:25 +00:00
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//===-- RegAllocLinearScan.cpp - Linear Scan register allocator -----------===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file was developed by the LLVM research group and is distributed under
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// the University of Illinois Open Source License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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//
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// This file implements a linear scan register allocator.
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//
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//===----------------------------------------------------------------------===//
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2004-02-24 08:58:30 +00:00
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2003-11-20 03:32:25 +00:00
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#define DEBUG_TYPE "regalloc"
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#include "llvm/Function.h"
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#include "llvm/CodeGen/LiveVariables.h"
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#include "llvm/CodeGen/MachineFunctionPass.h"
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#include "llvm/CodeGen/MachineInstr.h"
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#include "llvm/CodeGen/Passes.h"
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#include "llvm/CodeGen/SSARegMap.h"
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#include "llvm/Target/MRegisterInfo.h"
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#include "llvm/Target/TargetMachine.h"
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#include "Support/Debug.h"
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2004-07-04 07:59:06 +00:00
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#include "Support/Statistic.h"
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2004-05-30 07:46:27 +00:00
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#include "Support/STLExtras.h"
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2004-07-23 17:56:30 +00:00
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#include "LiveIntervalAnalysis.h"
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2004-02-23 00:53:31 +00:00
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#include "PhysRegTracker.h"
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2004-02-23 23:08:11 +00:00
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#include "VirtRegMap.h"
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2004-02-15 10:24:21 +00:00
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#include <algorithm>
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2004-05-08 03:50:03 +00:00
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#include <cmath>
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2004-05-30 07:24:39 +00:00
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#include <set>
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2004-07-22 08:14:44 +00:00
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#include <queue>
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2004-02-24 08:58:30 +00:00
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2003-11-20 03:32:25 +00:00
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using namespace llvm;
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namespace {
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2004-07-04 07:59:06 +00:00
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2004-08-04 09:46:26 +00:00
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Statistic<double> efficiency
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("regalloc", "Ratio of intervals processed over total intervals");
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static unsigned numIterations = 0;
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static unsigned numIntervals = 0;
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class RA : public MachineFunctionPass {
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private:
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MachineFunction* mf_;
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const TargetMachine* tm_;
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const MRegisterInfo* mri_;
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LiveIntervals* li_;
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typedef std::vector<LiveInterval*> IntervalPtrs;
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IntervalPtrs handled_, fixed_, active_, inactive_;
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typedef std::priority_queue<LiveInterval*,
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IntervalPtrs,
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greater_ptr<LiveInterval> > IntervalHeap;
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IntervalHeap unhandled_;
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std::auto_ptr<PhysRegTracker> prt_;
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std::auto_ptr<VirtRegMap> vrm_;
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std::auto_ptr<Spiller> spiller_;
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typedef std::vector<float> SpillWeights;
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SpillWeights spillWeights_;
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public:
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virtual const char* getPassName() const {
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return "Linear Scan Register Allocator";
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}
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2003-11-20 03:32:25 +00:00
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2004-08-04 09:46:26 +00:00
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virtual void getAnalysisUsage(AnalysisUsage &AU) const {
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AU.addRequired<LiveVariables>();
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AU.addRequired<LiveIntervals>();
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MachineFunctionPass::getAnalysisUsage(AU);
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}
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/// runOnMachineFunction - register allocate the whole function
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bool runOnMachineFunction(MachineFunction&);
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void releaseMemory();
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private:
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/// linearScan - the linear scan algorithm
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void linearScan();
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/// initIntervalSets - initializa the four interval sets:
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/// unhandled, fixed, active and inactive
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void initIntervalSets();
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/// processActiveIntervals - expire old intervals and move
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/// non-overlapping ones to the incative list
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void processActiveIntervals(LiveInterval* cur);
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2003-11-20 03:32:25 +00:00
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2004-08-04 09:46:26 +00:00
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/// processInactiveIntervals - expire old intervals and move
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/// overlapping ones to the active list
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void processInactiveIntervals(LiveInterval* cur);
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/// updateSpillWeights - updates the spill weights of the
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/// specifed physical register and its weight
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void updateSpillWeights(unsigned reg, SpillWeights::value_type weight);
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/// assignRegOrStackSlotAtInterval - assign a register if one
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/// is available, or spill.
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void assignRegOrStackSlotAtInterval(LiveInterval* cur);
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///
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/// register handling helpers
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///
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/// getFreePhysReg - return a free physical register for this
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/// virtual register interval if we have one, otherwise return
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/// 0
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unsigned getFreePhysReg(LiveInterval* cur);
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/// assignVirt2StackSlot - assigns this virtual register to a
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/// stack slot. returns the stack slot
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int assignVirt2StackSlot(unsigned virtReg);
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template <typename ItTy>
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void printIntervals(const char* const str, ItTy i, ItTy e) const {
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if (str) std::cerr << str << " intervals:\n";
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for (; i != e; ++i) {
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std::cerr << "\t" << **i << " -> ";
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unsigned reg = (*i)->reg;
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if (MRegisterInfo::isVirtualRegister(reg)) {
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reg = vrm_->getPhys(reg);
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2003-11-20 03:32:25 +00:00
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}
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2004-08-04 09:46:26 +00:00
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std::cerr << mri_->getName(reg) << '\n';
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}
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}
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};
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2003-11-20 03:32:25 +00:00
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}
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2004-02-01 20:13:26 +00:00
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void RA::releaseMemory()
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{
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2004-08-04 09:46:26 +00:00
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while (!unhandled_.empty()) unhandled_.pop();
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fixed_.clear();
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active_.clear();
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inactive_.clear();
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handled_.clear();
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2004-02-01 20:13:26 +00:00
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}
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2003-11-20 03:32:25 +00:00
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bool RA::runOnMachineFunction(MachineFunction &fn) {
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2004-08-04 09:46:26 +00:00
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mf_ = &fn;
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tm_ = &fn.getTarget();
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mri_ = tm_->getRegisterInfo();
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li_ = &getAnalysis<LiveIntervals>();
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if (!prt_.get()) prt_.reset(new PhysRegTracker(*mri_));
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vrm_.reset(new VirtRegMap(*mf_));
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if (!spiller_.get()) spiller_.reset(createSpiller());
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2003-12-21 05:43:40 +00:00
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2004-08-04 09:46:26 +00:00
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initIntervalSets();
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2003-11-20 03:32:25 +00:00
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2004-08-04 09:46:26 +00:00
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linearScan();
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2004-02-24 08:58:30 +00:00
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2004-08-04 09:46:26 +00:00
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spiller_->runOnMachineFunction(*mf_, *vrm_);
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2004-02-24 08:58:30 +00:00
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2004-08-04 09:46:26 +00:00
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return true;
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2004-02-24 08:58:30 +00:00
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}
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void RA::linearScan()
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{
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2004-08-04 09:46:26 +00:00
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// linear scan algorithm
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DEBUG(std::cerr << "********** LINEAR SCAN **********\n");
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DEBUG(std::cerr << "********** Function: "
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<< mf_->getFunction()->getName() << '\n');
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// DEBUG(printIntervals("unhandled", unhandled_.begin(), unhandled_.end()));
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DEBUG(printIntervals("fixed", fixed_.begin(), fixed_.end()));
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DEBUG(printIntervals("active", active_.begin(), active_.end()));
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DEBUG(printIntervals("inactive", inactive_.begin(), inactive_.end()));
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while (!unhandled_.empty()) {
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// pick the interval with the earliest start point
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LiveInterval* cur = unhandled_.top();
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unhandled_.pop();
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++numIterations;
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DEBUG(std::cerr << "\n*** CURRENT ***: " << *cur << '\n');
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processActiveIntervals(cur);
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processInactiveIntervals(cur);
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// if this register is fixed we are done
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if (MRegisterInfo::isPhysicalRegister(cur->reg)) {
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prt_->addRegUse(cur->reg);
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active_.push_back(cur);
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handled_.push_back(cur);
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2004-02-20 06:15:40 +00:00
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}
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2004-08-04 09:46:26 +00:00
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// otherwise we are allocating a virtual register. try to find
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// a free physical register or spill an interval in order to
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// assign it one (we could spill the current though).
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else {
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assignRegOrStackSlotAtInterval(cur);
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2004-07-22 08:14:44 +00:00
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}
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2004-08-04 09:46:26 +00:00
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DEBUG(printIntervals("active", active_.begin(), active_.end()));
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DEBUG(printIntervals("inactive", inactive_.begin(), inactive_.end()));
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}
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numIntervals += li_->getNumIntervals();
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efficiency = double(numIterations) / double(numIntervals);
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// expire any remaining active intervals
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for (IntervalPtrs::reverse_iterator
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i = active_.rbegin(); i != active_.rend(); ) {
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unsigned reg = (*i)->reg;
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DEBUG(std::cerr << "\tinterval " << **i << " expired\n");
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if (MRegisterInfo::isVirtualRegister(reg))
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reg = vrm_->getPhys(reg);
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prt_->delRegUse(reg);
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i = IntervalPtrs::reverse_iterator(active_.erase(i.base()-1));
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}
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// expire any remaining inactive intervals
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for (IntervalPtrs::reverse_iterator
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i = inactive_.rbegin(); i != inactive_.rend(); ) {
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DEBUG(std::cerr << "\tinterval " << **i << " expired\n");
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i = IntervalPtrs::reverse_iterator(inactive_.erase(i.base()-1));
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}
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DEBUG(std::cerr << *vrm_);
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2003-11-20 03:32:25 +00:00
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}
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2004-07-24 03:32:06 +00:00
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void RA::initIntervalSets()
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2004-01-07 09:20:58 +00:00
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{
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2004-08-04 09:46:26 +00:00
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assert(unhandled_.empty() && fixed_.empty() &&
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active_.empty() && inactive_.empty() &&
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"interval sets should be empty on initialization");
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for (LiveIntervals::iterator i = li_->begin(), e = li_->end(); i != e; ++i){
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unhandled_.push(&i->second);
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if (MRegisterInfo::isPhysicalRegister(i->second.reg))
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fixed_.push_back(&i->second);
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}
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2004-01-07 09:20:58 +00:00
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}
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void RA::processActiveIntervals(IntervalPtrs::value_type cur)
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2003-11-20 03:32:25 +00:00
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{
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2004-08-04 09:46:26 +00:00
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DEBUG(std::cerr << "\tprocessing active intervals:\n");
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for (IntervalPtrs::reverse_iterator
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i = active_.rbegin(); i != active_.rend();) {
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unsigned reg = (*i)->reg;
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// remove expired intervals
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if ((*i)->expiredAt(cur->start())) {
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DEBUG(std::cerr << "\t\tinterval " << **i << " expired\n");
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if (MRegisterInfo::isVirtualRegister(reg))
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reg = vrm_->getPhys(reg);
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prt_->delRegUse(reg);
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// remove from active
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i = IntervalPtrs::reverse_iterator(active_.erase(i.base()-1));
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2003-11-20 03:32:25 +00:00
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}
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2004-08-04 09:46:26 +00:00
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// move inactive intervals to inactive list
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else if (!(*i)->liveAt(cur->start())) {
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DEBUG(std::cerr << "\t\tinterval " << **i << " inactive\n");
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if (MRegisterInfo::isVirtualRegister(reg))
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reg = vrm_->getPhys(reg);
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prt_->delRegUse(reg);
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// add to inactive
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inactive_.push_back(*i);
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// remove from active
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i = IntervalPtrs::reverse_iterator(active_.erase(i.base()-1));
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}
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else {
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++i;
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}
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}
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2003-11-20 03:32:25 +00:00
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}
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2004-01-07 09:20:58 +00:00
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void RA::processInactiveIntervals(IntervalPtrs::value_type cur)
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2003-11-20 03:32:25 +00:00
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{
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2004-08-04 09:46:26 +00:00
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DEBUG(std::cerr << "\tprocessing inactive intervals:\n");
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for (IntervalPtrs::reverse_iterator
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i = inactive_.rbegin(); i != inactive_.rend();) {
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unsigned reg = (*i)->reg;
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// remove expired intervals
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if ((*i)->expiredAt(cur->start())) {
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DEBUG(std::cerr << "\t\tinterval " << **i << " expired\n");
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// remove from inactive
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i = IntervalPtrs::reverse_iterator(inactive_.erase(i.base()-1));
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}
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// move re-activated intervals in active list
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else if ((*i)->liveAt(cur->start())) {
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DEBUG(std::cerr << "\t\tinterval " << **i << " active\n");
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if (MRegisterInfo::isVirtualRegister(reg))
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reg = vrm_->getPhys(reg);
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prt_->addRegUse(reg);
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// add to active
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active_.push_back(*i);
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// remove from inactive
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i = IntervalPtrs::reverse_iterator(inactive_.erase(i.base()-1));
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}
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else {
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++i;
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2003-12-21 05:43:40 +00:00
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}
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2004-08-04 09:46:26 +00:00
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}
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2003-12-21 05:43:40 +00:00
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}
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2004-02-06 18:08:18 +00:00
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void RA::updateSpillWeights(unsigned reg, SpillWeights::value_type weight)
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{
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2004-08-04 09:46:26 +00:00
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spillWeights_[reg] += weight;
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for (const unsigned* as = mri_->getAliasSet(reg); *as; ++as)
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spillWeights_[*as] += weight;
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2003-11-20 03:32:25 +00:00
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}
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2004-07-22 08:14:44 +00:00
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void RA::assignRegOrStackSlotAtInterval(LiveInterval* cur)
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2003-11-20 03:32:25 +00:00
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{
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2004-08-04 09:46:26 +00:00
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DEBUG(std::cerr << "\tallocating current interval: ");
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PhysRegTracker backupPrt = *prt_;
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spillWeights_.assign(mri_->getNumRegs(), 0.0);
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// for each interval in active update spill weights
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for (IntervalPtrs::const_iterator i = active_.begin(), e = active_.end();
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i != e; ++i) {
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unsigned reg = (*i)->reg;
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if (MRegisterInfo::isVirtualRegister(reg))
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reg = vrm_->getPhys(reg);
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updateSpillWeights(reg, (*i)->weight);
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}
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// for every interval in inactive we overlap with, mark the
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// register as not free and update spill weights
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for (IntervalPtrs::const_iterator i = inactive_.begin(),
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e = inactive_.end(); i != e; ++i) {
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if (cur->overlaps(**i)) {
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unsigned reg = (*i)->reg;
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if (MRegisterInfo::isVirtualRegister(reg))
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reg = vrm_->getPhys(reg);
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prt_->addRegUse(reg);
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updateSpillWeights(reg, (*i)->weight);
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2003-11-20 03:32:25 +00:00
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|
|
}
|
2004-08-04 09:46:26 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
// for every interval in fixed we overlap with,
|
|
|
|
// mark the register as not free and update spill weights
|
|
|
|
for (IntervalPtrs::const_iterator i = fixed_.begin(),
|
|
|
|
e = fixed_.end(); i != e; ++i) {
|
|
|
|
if (cur->overlaps(**i)) {
|
|
|
|
unsigned reg = (*i)->reg;
|
|
|
|
prt_->addRegUse(reg);
|
|
|
|
updateSpillWeights(reg, (*i)->weight);
|
2004-02-06 18:08:18 +00:00
|
|
|
}
|
2004-08-04 09:46:26 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
unsigned physReg = getFreePhysReg(cur);
|
|
|
|
// restore the physical register tracker
|
|
|
|
*prt_ = backupPrt;
|
|
|
|
// if we find a free register, we are done: assign this virtual to
|
|
|
|
// the free physical register and add this interval to the active
|
|
|
|
// list.
|
|
|
|
if (physReg) {
|
|
|
|
DEBUG(std::cerr << mri_->getName(physReg) << '\n');
|
|
|
|
vrm_->assignVirt2Phys(cur->reg, physReg);
|
|
|
|
prt_->addRegUse(physReg);
|
|
|
|
active_.push_back(cur);
|
|
|
|
handled_.push_back(cur);
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
DEBUG(std::cerr << "no free registers\n");
|
|
|
|
|
|
|
|
DEBUG(std::cerr << "\tassigning stack slot at interval "<< *cur << ":\n");
|
|
|
|
|
|
|
|
float minWeight = HUGE_VAL;
|
|
|
|
unsigned minReg = 0;
|
|
|
|
const TargetRegisterClass* rc = mf_->getSSARegMap()->getRegClass(cur->reg);
|
|
|
|
for (TargetRegisterClass::iterator i = rc->allocation_order_begin(*mf_);
|
|
|
|
i != rc->allocation_order_end(*mf_); ++i) {
|
|
|
|
unsigned reg = *i;
|
|
|
|
if (minWeight > spillWeights_[reg]) {
|
|
|
|
minWeight = spillWeights_[reg];
|
|
|
|
minReg = reg;
|
2003-11-20 03:32:25 +00:00
|
|
|
}
|
2004-08-04 09:46:26 +00:00
|
|
|
}
|
|
|
|
DEBUG(std::cerr << "\t\tregister with min weight: "
|
|
|
|
<< mri_->getName(minReg) << " (" << minWeight << ")\n");
|
|
|
|
|
|
|
|
// if the current has the minimum weight, we need to spill it and
|
|
|
|
// add any added intervals back to unhandled, and restart
|
|
|
|
// linearscan.
|
|
|
|
if (cur->weight <= minWeight) {
|
|
|
|
DEBUG(std::cerr << "\t\t\tspilling(c): " << *cur << '\n';);
|
|
|
|
int slot = vrm_->assignVirt2StackSlot(cur->reg);
|
|
|
|
std::vector<LiveInterval*> added =
|
|
|
|
li_->addIntervalsForSpills(*cur, *vrm_, slot);
|
|
|
|
if (added.empty())
|
|
|
|
return; // Early exit if all spills were folded.
|
|
|
|
|
|
|
|
// Merge added with unhandled. Note that we know that
|
|
|
|
// addIntervalsForSpills returns intervals sorted by their starting
|
|
|
|
// point.
|
|
|
|
for (unsigned i = 0, e = added.size(); i != e; ++i)
|
|
|
|
unhandled_.push(added[i]);
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
|
|
|
|
// push the current interval back to unhandled since we are going
|
|
|
|
// to re-run at least this iteration. Since we didn't modify it it
|
|
|
|
// should go back right in the front of the list
|
|
|
|
unhandled_.push(cur);
|
|
|
|
|
|
|
|
// otherwise we spill all intervals aliasing the register with
|
|
|
|
// minimum weight, rollback to the interval with the earliest
|
|
|
|
// start point and let the linear scan algorithm run again
|
|
|
|
std::vector<LiveInterval*> added;
|
|
|
|
assert(MRegisterInfo::isPhysicalRegister(minReg) &&
|
|
|
|
"did not choose a register to spill?");
|
|
|
|
std::vector<bool> toSpill(mri_->getNumRegs(), false);
|
|
|
|
// we are going to spill minReg and all its aliases
|
|
|
|
toSpill[minReg] = true;
|
|
|
|
for (const unsigned* as = mri_->getAliasSet(minReg); *as; ++as)
|
|
|
|
toSpill[*as] = true;
|
|
|
|
|
|
|
|
// the earliest start of a spilled interval indicates up to where
|
|
|
|
// in handled we need to roll back
|
|
|
|
unsigned earliestStart = cur->start();
|
|
|
|
|
|
|
|
// set of spilled vregs (used later to rollback properly)
|
|
|
|
std::set<unsigned> spilled;
|
|
|
|
|
|
|
|
// spill live intervals of virtual regs mapped to the physical
|
|
|
|
// register we want to clear (and its aliases). we only spill
|
|
|
|
// those that overlap with the current interval as the rest do not
|
|
|
|
// affect its allocation. we also keep track of the earliest start
|
|
|
|
// of all spilled live intervals since this will mark our rollback
|
|
|
|
// point
|
|
|
|
for (IntervalPtrs::iterator
|
|
|
|
i = active_.begin(); i != active_.end(); ++i) {
|
|
|
|
unsigned reg = (*i)->reg;
|
|
|
|
if (MRegisterInfo::isVirtualRegister(reg) &&
|
|
|
|
toSpill[vrm_->getPhys(reg)] &&
|
|
|
|
cur->overlaps(**i)) {
|
|
|
|
DEBUG(std::cerr << "\t\t\tspilling(a): " << **i << '\n');
|
|
|
|
earliestStart = std::min(earliestStart, (*i)->start());
|
|
|
|
int slot = vrm_->assignVirt2StackSlot((*i)->reg);
|
|
|
|
std::vector<LiveInterval*> newIs =
|
|
|
|
li_->addIntervalsForSpills(**i, *vrm_, slot);
|
|
|
|
std::copy(newIs.begin(), newIs.end(), std::back_inserter(added));
|
|
|
|
spilled.insert(reg);
|
2003-12-23 18:00:33 +00:00
|
|
|
}
|
2004-08-04 09:46:26 +00:00
|
|
|
}
|
|
|
|
for (IntervalPtrs::iterator
|
|
|
|
i = inactive_.begin(); i != inactive_.end(); ++i) {
|
|
|
|
unsigned reg = (*i)->reg;
|
|
|
|
if (MRegisterInfo::isVirtualRegister(reg) &&
|
|
|
|
toSpill[vrm_->getPhys(reg)] &&
|
|
|
|
cur->overlaps(**i)) {
|
|
|
|
DEBUG(std::cerr << "\t\t\tspilling(i): " << **i << '\n');
|
|
|
|
earliestStart = std::min(earliestStart, (*i)->start());
|
|
|
|
int slot = vrm_->assignVirt2StackSlot((*i)->reg);
|
|
|
|
std::vector<LiveInterval*> newIs =
|
|
|
|
li_->addIntervalsForSpills(**i, *vrm_, slot);
|
|
|
|
std::copy(newIs.begin(), newIs.end(), std::back_inserter(added));
|
|
|
|
spilled.insert(reg);
|
2003-11-20 03:32:25 +00:00
|
|
|
}
|
2004-08-04 09:46:26 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
DEBUG(std::cerr << "\t\trolling back to: " << earliestStart << '\n');
|
|
|
|
// scan handled in reverse order up to the earliaset start of a
|
|
|
|
// spilled live interval and undo each one, restoring the state of
|
|
|
|
// unhandled
|
|
|
|
while (!handled_.empty()) {
|
|
|
|
LiveInterval* i = handled_.back();
|
|
|
|
// if this interval starts before t we are done
|
|
|
|
if (i->start() < earliestStart)
|
|
|
|
break;
|
|
|
|
DEBUG(std::cerr << "\t\t\tundo changes for: " << *i << '\n');
|
|
|
|
handled_.pop_back();
|
|
|
|
// when undoing a live interval allocation we must know if it
|
|
|
|
// is active or inactive to properly update the PhysRegTracker
|
|
|
|
// and the VirtRegMap
|
|
|
|
IntervalPtrs::iterator it;
|
|
|
|
if ((it = find(active_.begin(), active_.end(), i)) != active_.end()) {
|
|
|
|
active_.erase(it);
|
|
|
|
if (MRegisterInfo::isPhysicalRegister(i->reg)) {
|
|
|
|
prt_->delRegUse(i->reg);
|
|
|
|
unhandled_.push(i);
|
|
|
|
}
|
|
|
|
else {
|
|
|
|
if (!spilled.count(i->reg))
|
|
|
|
unhandled_.push(i);
|
|
|
|
prt_->delRegUse(vrm_->getPhys(i->reg));
|
|
|
|
vrm_->clearVirt(i->reg);
|
|
|
|
}
|
2003-12-21 05:43:40 +00:00
|
|
|
}
|
2004-08-04 09:46:26 +00:00
|
|
|
else if ((it = find(inactive_.begin(), inactive_.end(), i)) != inactive_.end()) {
|
|
|
|
inactive_.erase(it);
|
|
|
|
if (MRegisterInfo::isPhysicalRegister(i->reg))
|
|
|
|
unhandled_.push(i);
|
|
|
|
else {
|
|
|
|
if (!spilled.count(i->reg))
|
|
|
|
unhandled_.push(i);
|
|
|
|
vrm_->clearVirt(i->reg);
|
|
|
|
}
|
2004-02-06 18:08:18 +00:00
|
|
|
}
|
2004-08-04 09:46:26 +00:00
|
|
|
else {
|
|
|
|
if (MRegisterInfo::isVirtualRegister(i->reg))
|
|
|
|
vrm_->clearVirt(i->reg);
|
|
|
|
unhandled_.push(i);
|
2004-02-15 10:24:21 +00:00
|
|
|
}
|
2004-08-04 09:46:26 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
// scan the rest and undo each interval that expired after t and
|
|
|
|
// insert it in active (the next iteration of the algorithm will
|
|
|
|
// put it in inactive if required)
|
|
|
|
IntervalPtrs::iterator i = handled_.begin(), e = handled_.end();
|
|
|
|
for (; i != e; ++i) {
|
|
|
|
if (!(*i)->expiredAt(earliestStart) && (*i)->expiredAt(cur->start())) {
|
|
|
|
DEBUG(std::cerr << "\t\t\tundo changes for: " << **i << '\n');
|
|
|
|
active_.push_back(*i);
|
|
|
|
if (MRegisterInfo::isPhysicalRegister((*i)->reg))
|
|
|
|
prt_->addRegUse((*i)->reg);
|
|
|
|
else
|
|
|
|
prt_->addRegUse(vrm_->getPhys((*i)->reg));
|
2004-02-06 18:08:18 +00:00
|
|
|
}
|
2004-08-04 09:46:26 +00:00
|
|
|
}
|
2004-05-30 07:24:39 +00:00
|
|
|
|
2004-08-04 09:46:26 +00:00
|
|
|
std::sort(added.begin(), added.end(), less_ptr<LiveInterval>());
|
|
|
|
// merge added with unhandled
|
|
|
|
for (unsigned i = 0, e = added.size(); i != e; ++i)
|
|
|
|
unhandled_.push(added[i]);
|
2004-02-15 10:24:21 +00:00
|
|
|
}
|
2003-12-21 05:43:40 +00:00
|
|
|
|
2004-07-22 08:14:44 +00:00
|
|
|
unsigned RA::getFreePhysReg(LiveInterval* cur)
|
2003-11-20 03:32:25 +00:00
|
|
|
{
|
2004-08-04 09:46:26 +00:00
|
|
|
const TargetRegisterClass* rc = mf_->getSSARegMap()->getRegClass(cur->reg);
|
|
|
|
|
|
|
|
for (TargetRegisterClass::iterator i = rc->allocation_order_begin(*mf_);
|
|
|
|
i != rc->allocation_order_end(*mf_); ++i) {
|
|
|
|
unsigned reg = *i;
|
|
|
|
if (prt_->isRegAvail(reg))
|
|
|
|
return reg;
|
|
|
|
}
|
|
|
|
return 0;
|
2003-11-20 03:32:25 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
FunctionPass* llvm::createLinearScanRegisterAllocator() {
|
2004-08-04 09:46:26 +00:00
|
|
|
return new RA();
|
2003-11-20 03:32:25 +00:00
|
|
|
}
|