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-rw-r--r--contrib/llvm/lib/CodeGen/RegAllocLinearScan.cpp109
1 files changed, 57 insertions, 52 deletions
diff --git a/contrib/llvm/lib/CodeGen/RegAllocLinearScan.cpp b/contrib/llvm/lib/CodeGen/RegAllocLinearScan.cpp
index 5c62354..b959878 100644
--- a/contrib/llvm/lib/CodeGen/RegAllocLinearScan.cpp
+++ b/contrib/llvm/lib/CodeGen/RegAllocLinearScan.cpp
@@ -12,13 +12,14 @@
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "regalloc"
+#include "LiveDebugVariables.h"
#include "VirtRegMap.h"
#include "VirtRegRewriter.h"
#include "Spiller.h"
+#include "llvm/Analysis/AliasAnalysis.h"
#include "llvm/Function.h"
#include "llvm/CodeGen/CalcSpillWeights.h"
#include "llvm/CodeGen/LiveIntervalAnalysis.h"
-#include "llvm/CodeGen/LiveStackAnalysis.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/MachineInstr.h"
#include "llvm/CodeGen/MachineLoopInfo.h"
@@ -91,6 +92,19 @@ namespace {
struct RALinScan : public MachineFunctionPass {
static char ID;
RALinScan() : MachineFunctionPass(ID) {
+ initializeLiveDebugVariablesPass(*PassRegistry::getPassRegistry());
+ initializeLiveIntervalsPass(*PassRegistry::getPassRegistry());
+ initializeStrongPHIEliminationPass(*PassRegistry::getPassRegistry());
+ initializeRegisterCoalescerAnalysisGroup(
+ *PassRegistry::getPassRegistry());
+ initializeCalculateSpillWeightsPass(*PassRegistry::getPassRegistry());
+ initializePreAllocSplittingPass(*PassRegistry::getPassRegistry());
+ initializeLiveStacksPass(*PassRegistry::getPassRegistry());
+ initializeMachineDominatorTreePass(*PassRegistry::getPassRegistry());
+ initializeMachineLoopInfoPass(*PassRegistry::getPassRegistry());
+ initializeVirtRegMapPass(*PassRegistry::getPassRegistry());
+ initializeMachineDominatorTreePass(*PassRegistry::getPassRegistry());
+
// Initialize the queue to record recently-used registers.
if (NumRecentlyUsedRegs > 0)
RecentRegs.resize(NumRecentlyUsedRegs, 0);
@@ -127,7 +141,6 @@ namespace {
BitVector allocatableRegs_;
BitVector reservedRegs_;
LiveIntervals* li_;
- LiveStacks* ls_;
MachineLoopInfo *loopInfo;
/// handled_ - Intervals are added to the handled_ set in the order of their
@@ -183,6 +196,8 @@ namespace {
virtual void getAnalysisUsage(AnalysisUsage &AU) const {
AU.setPreservesCFG();
+ AU.addRequired<AliasAnalysis>();
+ AU.addPreserved<AliasAnalysis>();
AU.addRequired<LiveIntervals>();
AU.addPreserved<SlotIndexes>();
if (StrongPHIElim)
@@ -193,12 +208,15 @@ namespace {
AU.addRequired<CalculateSpillWeights>();
if (PreSplitIntervals)
AU.addRequiredID(PreAllocSplittingID);
- AU.addRequired<LiveStacks>();
- AU.addPreserved<LiveStacks>();
+ AU.addRequiredID(LiveStacksID);
+ AU.addPreservedID(LiveStacksID);
AU.addRequired<MachineLoopInfo>();
AU.addPreserved<MachineLoopInfo>();
AU.addRequired<VirtRegMap>();
AU.addPreserved<VirtRegMap>();
+ AU.addRequired<LiveDebugVariables>();
+ AU.addPreserved<LiveDebugVariables>();
+ AU.addRequiredID(MachineDominatorsID);
AU.addPreservedID(MachineDominatorsID);
MachineFunctionPass::getAnalysisUsage(AU);
}
@@ -370,8 +388,19 @@ namespace {
char RALinScan::ID = 0;
}
-INITIALIZE_PASS(RALinScan, "linearscan-regalloc",
- "Linear Scan Register Allocator", false, false);
+INITIALIZE_PASS_BEGIN(RALinScan, "linearscan-regalloc",
+ "Linear Scan Register Allocator", false, false)
+INITIALIZE_PASS_DEPENDENCY(LiveIntervals)
+INITIALIZE_PASS_DEPENDENCY(StrongPHIElimination)
+INITIALIZE_PASS_DEPENDENCY(CalculateSpillWeights)
+INITIALIZE_PASS_DEPENDENCY(PreAllocSplitting)
+INITIALIZE_PASS_DEPENDENCY(LiveStacks)
+INITIALIZE_PASS_DEPENDENCY(MachineLoopInfo)
+INITIALIZE_PASS_DEPENDENCY(VirtRegMap)
+INITIALIZE_AG_DEPENDENCY(RegisterCoalescer)
+INITIALIZE_AG_DEPENDENCY(AliasAnalysis)
+INITIALIZE_PASS_END(RALinScan, "linearscan-regalloc",
+ "Linear Scan Register Allocator", false, false)
void RALinScan::ComputeRelatedRegClasses() {
// First pass, add all reg classes to the union, and determine at least one
@@ -402,8 +431,12 @@ void RALinScan::ComputeRelatedRegClasses() {
for (DenseMap<unsigned, const TargetRegisterClass*>::iterator
I = OneClassForEachPhysReg.begin(), E = OneClassForEachPhysReg.end();
I != E; ++I)
- for (const unsigned *AS = tri_->getAliasSet(I->first); *AS; ++AS)
- RelatedRegClasses.unionSets(I->second, OneClassForEachPhysReg[*AS]);
+ for (const unsigned *AS = tri_->getAliasSet(I->first); *AS; ++AS) {
+ const TargetRegisterClass *AliasClass =
+ OneClassForEachPhysReg.lookup(*AS);
+ if (AliasClass)
+ RelatedRegClasses.unionSets(I->second, AliasClass);
+ }
}
/// attemptTrivialCoalescing - If a simple interval is defined by a copy, try
@@ -431,8 +464,7 @@ unsigned RALinScan::attemptTrivialCoalescing(LiveInterval &cur, unsigned Reg) {
unsigned CandReg;
{
MachineInstr *CopyMI;
- if (vni->def != SlotIndex() && vni->isDefAccurate() &&
- (CopyMI = li_->getInstructionFromIndex(vni->def)) && CopyMI->isCopy())
+ if ((CopyMI = li_->getInstructionFromIndex(vni->def)) && CopyMI->isCopy())
// Defined by a copy, try to extend SrcReg forward
CandReg = CopyMI->getOperand(1).getReg();
else if (TrivCoalesceEnds &&
@@ -442,6 +474,10 @@ unsigned RALinScan::attemptTrivialCoalescing(LiveInterval &cur, unsigned Reg) {
CandReg = CopyMI->getOperand(0).getReg();
else
return Reg;
+
+ // If the target of the copy is a sub-register then don't coalesce.
+ if(CopyMI->getOperand(0).getSubReg())
+ return Reg;
}
if (TargetRegisterInfo::isVirtualRegister(CandReg)) {
@@ -478,7 +514,6 @@ bool RALinScan::runOnMachineFunction(MachineFunction &fn) {
allocatableRegs_ = tri_->getAllocatableSet(fn);
reservedRegs_ = tri_->getReservedRegs(fn);
li_ = &getAnalysis<LiveIntervals>();
- ls_ = &getAnalysis<LiveStacks>();
loopInfo = &getAnalysis<MachineLoopInfo>();
// We don't run the coalescer here because we have no reason to
@@ -505,6 +540,9 @@ bool RALinScan::runOnMachineFunction(MachineFunction &fn) {
// Rewrite spill code and update the PhysRegsUsed set.
rewriter_->runOnMachineFunction(*mf_, *vrm_, li_);
+ // Write out new DBG_VALUE instructions.
+ getAnalysis<LiveDebugVariables>().emitDebugValues(vrm_);
+
assert(unhandled_.empty() && "Unhandled live intervals remain!");
finalizeRegUses();
@@ -638,8 +676,6 @@ void RALinScan::linearScan() {
// Look for physical registers that end up not being allocated even though
// register allocator had to spill other registers in its register class.
- if (ls_->getNumIntervals() == 0)
- return;
if (!vrm_->FindUnusedRegisters(li_))
return;
}
@@ -784,30 +820,6 @@ static void RevertVectorIteratorsTo(RALinScan::IntervalPtrs &V,
}
}
-/// addStackInterval - Create a LiveInterval for stack if the specified live
-/// interval has been spilled.
-static void addStackInterval(LiveInterval *cur, LiveStacks *ls_,
- LiveIntervals *li_,
- MachineRegisterInfo* mri_, VirtRegMap &vrm_) {
- int SS = vrm_.getStackSlot(cur->reg);
- if (SS == VirtRegMap::NO_STACK_SLOT)
- return;
-
- const TargetRegisterClass *RC = mri_->getRegClass(cur->reg);
- LiveInterval &SI = ls_->getOrCreateInterval(SS, RC);
-
- VNInfo *VNI;
- if (SI.hasAtLeastOneValue())
- VNI = SI.getValNumInfo(0);
- else
- VNI = SI.getNextValue(SlotIndex(), 0, false,
- ls_->getVNInfoAllocator());
-
- LiveInterval &RI = li_->getInterval(cur->reg);
- // FIXME: This may be overly conservative.
- SI.MergeRangesInAsValue(RI, VNI);
-}
-
/// getConflictWeight - Return the number of conflicts between cur
/// live interval and defs and uses of Reg weighted by loop depthes.
static
@@ -925,13 +937,9 @@ LiveInterval *RALinScan::hasNextReloadInterval(LiveInterval *cur) {
}
void RALinScan::DowngradeRegister(LiveInterval *li, unsigned Reg) {
- bool isNew = DowngradedRegs.insert(Reg);
- isNew = isNew; // Silence compiler warning.
- assert(isNew && "Multiple reloads holding the same register?");
- DowngradeMap.insert(std::make_pair(li->reg, Reg));
- for (const unsigned *AS = tri_->getAliasSet(Reg); *AS; ++AS) {
- isNew = DowngradedRegs.insert(*AS);
- isNew = isNew; // Silence compiler warning.
+ for (const unsigned *AS = tri_->getOverlaps(Reg); *AS; ++AS) {
+ bool isNew = DowngradedRegs.insert(*AS);
+ (void)isNew; // Silence compiler warning.
assert(isNew && "Multiple reloads holding the same register?");
DowngradeMap.insert(std::make_pair(li->reg, *AS));
}
@@ -957,10 +965,11 @@ namespace {
/// assignRegOrStackSlotAtInterval - assign a register if one is available, or
/// spill.
void RALinScan::assignRegOrStackSlotAtInterval(LiveInterval* cur) {
- DEBUG(dbgs() << "\tallocating current interval: ");
+ const TargetRegisterClass *RC = mri_->getRegClass(cur->reg);
+ DEBUG(dbgs() << "\tallocating current interval from "
+ << RC->getName() << ": ");
// This is an implicitly defined live interval, just assign any register.
- const TargetRegisterClass *RC = mri_->getRegClass(cur->reg);
if (cur->empty()) {
unsigned physReg = vrm_->getRegAllocPref(cur->reg);
if (!physReg)
@@ -984,8 +993,7 @@ void RALinScan::assignRegOrStackSlotAtInterval(LiveInterval* cur) {
// one, e.g. X86::mov32to32_. These move instructions are not coalescable.
if (!vrm_->getRegAllocPref(cur->reg) && cur->hasAtLeastOneValue()) {
VNInfo *vni = cur->begin()->valno;
- if ((vni->def != SlotIndex()) && !vni->isUnused() &&
- vni->isDefAccurate()) {
+ if (!vni->isUnused()) {
MachineInstr *CopyMI = li_->getInstructionFromIndex(vni->def);
if (CopyMI && CopyMI->isCopy()) {
unsigned DstSubReg = CopyMI->getOperand(0).getSubReg();
@@ -1225,7 +1233,6 @@ void RALinScan::assignRegOrStackSlotAtInterval(LiveInterval* cur) {
spiller_->spill(cur, added, spillIs);
std::sort(added.begin(), added.end(), LISorter());
- addStackInterval(cur, ls_, li_, mri_, *vrm_);
if (added.empty())
return; // Early exit if all spills were folded.
@@ -1300,7 +1307,6 @@ void RALinScan::assignRegOrStackSlotAtInterval(LiveInterval* cur) {
if (sli->beginIndex() < earliestStart)
earliestStart = sli->beginIndex();
spiller_->spill(sli, added, spillIs);
- addStackInterval(sli, ls_, li_, mri_, *vrm_);
spilled.insert(sli->reg);
}
@@ -1419,8 +1425,7 @@ unsigned RALinScan::getFreePhysReg(LiveInterval* cur,
std::pair<unsigned, unsigned> Hint = mri_->getRegAllocationHint(cur->reg);
// Resolve second part of the hint (if possible) given the current allocation.
unsigned physReg = Hint.second;
- if (physReg &&
- TargetRegisterInfo::isVirtualRegister(physReg) && vrm_->hasPhys(physReg))
+ if (TargetRegisterInfo::isVirtualRegister(physReg) && vrm_->hasPhys(physReg))
physReg = vrm_->getPhys(physReg);
TargetRegisterClass::iterator I, E;
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