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-rw-r--r--lib/CodeGen/LiveIntervalAnalysis.cpp90
1 files changed, 53 insertions, 37 deletions
diff --git a/lib/CodeGen/LiveIntervalAnalysis.cpp b/lib/CodeGen/LiveIntervalAnalysis.cpp
index e1c3217a775e..15595609e904 100644
--- a/lib/CodeGen/LiveIntervalAnalysis.cpp
+++ b/lib/CodeGen/LiveIntervalAnalysis.cpp
@@ -15,13 +15,13 @@
//
//===----------------------------------------------------------------------===//
-#define DEBUG_TYPE "regalloc"
#include "llvm/CodeGen/LiveIntervalAnalysis.h"
#include "LiveRangeCalc.h"
#include "llvm/ADT/DenseSet.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/Analysis/AliasAnalysis.h"
#include "llvm/CodeGen/LiveVariables.h"
+#include "llvm/CodeGen/MachineBlockFrequencyInfo.h"
#include "llvm/CodeGen/MachineDominators.h"
#include "llvm/CodeGen/MachineInstr.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
@@ -41,6 +41,8 @@
#include <limits>
using namespace llvm;
+#define DEBUG_TYPE "regalloc"
+
char LiveIntervals::ID = 0;
char &llvm::LiveIntervalsID = LiveIntervals::ID;
INITIALIZE_PASS_BEGIN(LiveIntervals, "liveintervals",
@@ -78,7 +80,7 @@ void LiveIntervals::getAnalysisUsage(AnalysisUsage &AU) const {
}
LiveIntervals::LiveIntervals() : MachineFunctionPass(ID),
- DomTree(0), LRCalc(0) {
+ DomTree(nullptr), LRCalc(nullptr) {
initializeLiveIntervalsPass(*PassRegistry::getPassRegistry());
}
@@ -184,6 +186,7 @@ void LiveIntervals::computeVirtRegInterval(LiveInterval &LI) {
LRCalc->reset(MF, getSlotIndexes(), DomTree, &getVNInfoAllocator());
LRCalc->createDeadDefs(LI);
LRCalc->extendToUses(LI);
+ computeDeadValues(&LI, LI, nullptr, nullptr);
}
void LiveIntervals::computeVirtRegs() {
@@ -325,8 +328,10 @@ bool LiveIntervals::shrinkToUses(LiveInterval *li,
SmallPtrSet<MachineBasicBlock*, 16> LiveOut;
// Visit all instructions reading li->reg.
- for (MachineRegisterInfo::reg_iterator I = MRI->reg_begin(li->reg);
- MachineInstr *UseMI = I.skipInstruction();) {
+ for (MachineRegisterInfo::reg_instr_iterator
+ I = MRI->reg_instr_begin(li->reg), E = MRI->reg_instr_end();
+ I != E; ) {
+ MachineInstr *UseMI = &*(I++);
if (UseMI->isDebugValue() || !UseMI->readsVirtualRegister(li->reg))
continue;
SlotIndex Idx = getInstructionIndex(UseMI).getRegSlot();
@@ -408,21 +413,34 @@ bool LiveIntervals::shrinkToUses(LiveInterval *li,
// Handle dead values.
bool CanSeparate = false;
+ computeDeadValues(li, NewLR, &CanSeparate, dead);
+
+ // Move the trimmed segments back.
+ li->segments.swap(NewLR.segments);
+ DEBUG(dbgs() << "Shrunk: " << *li << '\n');
+ return CanSeparate;
+}
+
+void LiveIntervals::computeDeadValues(LiveInterval *li,
+ LiveRange &LR,
+ bool *CanSeparate,
+ SmallVectorImpl<MachineInstr*> *dead) {
for (LiveInterval::vni_iterator I = li->vni_begin(), E = li->vni_end();
I != E; ++I) {
VNInfo *VNI = *I;
if (VNI->isUnused())
continue;
- LiveRange::iterator LRI = NewLR.FindSegmentContaining(VNI->def);
- assert(LRI != NewLR.end() && "Missing segment for PHI");
+ LiveRange::iterator LRI = LR.FindSegmentContaining(VNI->def);
+ assert(LRI != LR.end() && "Missing segment for PHI");
if (LRI->end != VNI->def.getDeadSlot())
continue;
if (VNI->isPHIDef()) {
// This is a dead PHI. Remove it.
VNI->markUnused();
- NewLR.removeSegment(LRI->start, LRI->end);
+ LR.removeSegment(LRI->start, LRI->end);
DEBUG(dbgs() << "Dead PHI at " << VNI->def << " may separate interval\n");
- CanSeparate = true;
+ if (CanSeparate)
+ *CanSeparate = true;
} else {
// This is a dead def. Make sure the instruction knows.
MachineInstr *MI = getInstructionFromIndex(VNI->def);
@@ -434,11 +452,6 @@ bool LiveIntervals::shrinkToUses(LiveInterval *li,
}
}
}
-
- // Move the trimmed segments back.
- li->segments.swap(NewLR.segments);
- DEBUG(dbgs() << "Shrunk: " << *li << '\n');
- return CanSeparate;
}
void LiveIntervals::extendToIndices(LiveRange &LR,
@@ -458,7 +471,7 @@ void LiveIntervals::pruneValue(LiveInterval *LI, SlotIndex Kill,
MachineBasicBlock *KillMBB = Indexes->getMBBFromIndex(Kill);
SlotIndex MBBStart, MBBEnd;
- tie(MBBStart, MBBEnd) = Indexes->getMBBRange(KillMBB);
+ std::tie(MBBStart, MBBEnd) = Indexes->getMBBRange(KillMBB);
// If VNI isn't live out from KillMBB, the value is trivially pruned.
if (LRQ.endPoint() < MBBEnd) {
@@ -485,7 +498,7 @@ void LiveIntervals::pruneValue(LiveInterval *LI, SlotIndex Kill,
MachineBasicBlock *MBB = *I;
// Check if VNI is live in to MBB.
- tie(MBBStart, MBBEnd) = Indexes->getMBBRange(MBB);
+ std::tie(MBBStart, MBBEnd) = Indexes->getMBBRange(MBB);
LiveQueryResult LRQ = LI->Query(MBBStart);
if (LRQ.valueIn() != VNI) {
// This block isn't part of the VNI segment. Prune the search.
@@ -569,9 +582,9 @@ void LiveIntervals::addKillFlags(const VirtRegMap *VRM) {
break;
}
if (CancelKill)
- MI->clearRegisterKills(Reg, NULL);
+ MI->clearRegisterKills(Reg, nullptr);
else
- MI->addRegisterKilled(Reg, NULL);
+ MI->addRegisterKilled(Reg, nullptr);
}
}
}
@@ -587,17 +600,17 @@ LiveIntervals::intervalIsInOneMBB(const LiveInterval &LI) const {
SlotIndex Start = LI.beginIndex();
if (Start.isBlock())
- return NULL;
+ return nullptr;
SlotIndex Stop = LI.endIndex();
if (Stop.isBlock())
- return NULL;
+ return nullptr;
// getMBBFromIndex doesn't need to search the MBB table when both indexes
// belong to proper instructions.
MachineBasicBlock *MBB1 = Indexes->getMBBFromIndex(Start);
MachineBasicBlock *MBB2 = Indexes->getMBBFromIndex(Stop);
- return MBB1 == MBB2 ? MBB1 : NULL;
+ return MBB1 == MBB2 ? MBB1 : nullptr;
}
bool
@@ -620,9 +633,12 @@ LiveIntervals::hasPHIKill(const LiveInterval &LI, const VNInfo *VNI) const {
}
float
-LiveIntervals::getSpillWeight(bool isDef, bool isUse, BlockFrequency freq) {
- const float Scale = 1.0f / BlockFrequency::getEntryFrequency();
- return (isDef + isUse) * (freq.getFrequency() * Scale);
+LiveIntervals::getSpillWeight(bool isDef, bool isUse,
+ const MachineBlockFrequencyInfo *MBFI,
+ const MachineInstr *MI) {
+ BlockFrequency Freq = MBFI->getBlockFreq(MI->getParent());
+ const float Scale = 1.0f / MBFI->getEntryFreq();
+ return (isDef + isUse) * (Freq.getFrequency() * Scale);
}
LiveRange::Segment
@@ -870,8 +886,8 @@ private:
// values. The new range should be placed immediately before NewI, move any
// intermediate ranges up.
assert(NewI != I && "Inconsistent iterators");
- std::copy(llvm::next(I), NewI, I);
- *llvm::prior(NewI)
+ std::copy(std::next(I), NewI, I);
+ *std::prev(NewI)
= LiveRange::Segment(DefVNI->def, NewIdx.getDeadSlot(), DefVNI);
}
@@ -916,7 +932,7 @@ private:
if (I == E || !SlotIndex::isSameInstr(I->start, OldIdx)) {
// No def, search for the new kill.
// This can never be an early clobber kill since there is no def.
- llvm::prior(I)->end = findLastUseBefore(Reg).getRegSlot();
+ std::prev(I)->end = findLastUseBefore(Reg).getRegSlot();
return;
}
}
@@ -952,7 +968,7 @@ private:
// DefVNI is a dead def. It may have been moved across other values in LR,
// so move I up to NewI. Slide [NewI;I) down one position.
- std::copy_backward(NewI, I, llvm::next(I));
+ std::copy_backward(NewI, I, std::next(I));
*NewI = LiveRange::Segment(DefVNI->def, NewIdx.getDeadSlot(), DefVNI);
}
@@ -964,11 +980,11 @@ private:
"No RegMask at OldIdx.");
*RI = NewIdx.getRegSlot();
assert((RI == LIS.RegMaskSlots.begin() ||
- SlotIndex::isEarlierInstr(*llvm::prior(RI), *RI)) &&
- "Cannot move regmask instruction above another call");
- assert((llvm::next(RI) == LIS.RegMaskSlots.end() ||
- SlotIndex::isEarlierInstr(*RI, *llvm::next(RI))) &&
- "Cannot move regmask instruction below another call");
+ SlotIndex::isEarlierInstr(*std::prev(RI), *RI)) &&
+ "Cannot move regmask instruction above another call");
+ assert((std::next(RI) == LIS.RegMaskSlots.end() ||
+ SlotIndex::isEarlierInstr(*RI, *std::next(RI))) &&
+ "Cannot move regmask instruction below another call");
}
// Return the last use of reg between NewIdx and OldIdx.
@@ -976,10 +992,10 @@ private:
if (TargetRegisterInfo::isVirtualRegister(Reg)) {
SlotIndex LastUse = NewIdx;
- for (MachineRegisterInfo::use_nodbg_iterator
- UI = MRI.use_nodbg_begin(Reg),
- UE = MRI.use_nodbg_end();
- UI != UE; UI.skipInstruction()) {
+ for (MachineRegisterInfo::use_instr_nodbg_iterator
+ UI = MRI.use_instr_nodbg_begin(Reg),
+ UE = MRI.use_instr_nodbg_end();
+ UI != UE; ++UI) {
const MachineInstr* MI = &*UI;
SlotIndex InstSlot = LIS.getSlotIndexes()->getInstructionIndex(MI);
if (InstSlot > LastUse && InstSlot < OldIdx)
@@ -1121,7 +1137,7 @@ LiveIntervals::repairIntervalsInRange(MachineBasicBlock *MBB,
if (LII->end.isDead()) {
SlotIndex prevStart;
if (LII != LI.begin())
- prevStart = llvm::prior(LII)->start;
+ prevStart = std::prev(LII)->start;
// FIXME: This could be more efficient if there was a
// removeSegment method that returned an iterator.
generated by cgit v1.2.3 (git 2.25.1) at 2025-10-31 16:31:30 +0000