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-rw-r--r--lib/CodeGen/InlineSpiller.cpp85
1 files changed, 54 insertions, 31 deletions
diff --git a/lib/CodeGen/InlineSpiller.cpp b/lib/CodeGen/InlineSpiller.cpp
index bb0e642313..0f7ba8e01e 100644
--- a/lib/CodeGen/InlineSpiller.cpp
+++ b/lib/CodeGen/InlineSpiller.cpp
@@ -21,8 +21,9 @@
#include "llvm/CodeGen/LiveIntervalAnalysis.h"
#include "llvm/CodeGen/LiveRangeEdit.h"
#include "llvm/CodeGen/LiveStackAnalysis.h"
-#include "llvm/CodeGen/MachineDominators.h"
#include "llvm/CodeGen/MachineBlockFrequencyInfo.h"
+#include "llvm/CodeGen/MachineBranchProbabilityInfo.h"
+#include "llvm/CodeGen/MachineDominators.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
@@ -153,7 +154,7 @@ public:
TRI(*mf.getTarget().getRegisterInfo()),
MBFI(pass.getAnalysis<MachineBlockFrequencyInfo>()) {}
- void spill(LiveRangeEdit &);
+ void spill(LiveRangeEdit &) override;
private:
bool isSnippet(const LiveInterval &SnipLI);
@@ -238,9 +239,10 @@ bool InlineSpiller::isSnippet(const LiveInterval &SnipLI) {
MachineInstr *UseMI = 0;
// Check that all uses satisfy our criteria.
- for (MachineRegisterInfo::reg_nodbg_iterator
- RI = MRI.reg_nodbg_begin(SnipLI.reg);
- MachineInstr *MI = RI.skipInstruction();) {
+ for (MachineRegisterInfo::reg_instr_nodbg_iterator
+ RI = MRI.reg_instr_nodbg_begin(SnipLI.reg),
+ E = MRI.reg_instr_nodbg_end(); RI != E; ) {
+ MachineInstr *MI = &*(RI++);
// Allow copies to/from Reg.
if (isFullCopyOf(MI, Reg))
@@ -277,8 +279,9 @@ void InlineSpiller::collectRegsToSpill() {
if (Original == Reg)
return;
- for (MachineRegisterInfo::reg_iterator RI = MRI.reg_begin(Reg);
- MachineInstr *MI = RI.skipInstruction();) {
+ for (MachineRegisterInfo::reg_instr_iterator
+ RI = MRI.reg_instr_begin(Reg), E = MRI.reg_instr_end(); RI != E; ) {
+ MachineInstr *MI = &*(RI++);
unsigned SnipReg = isFullCopyOf(MI, Reg);
if (!isSibling(SnipReg))
continue;
@@ -438,7 +441,20 @@ void InlineSpiller::propagateSiblingValue(SibValueMap::iterator SVIIter,
// Also hoist spills to blocks with smaller loop depth, but make sure
// that the new value dominates. Non-phi dependents are always
// dominated, phis need checking.
+
+ const BranchProbability MarginProb(4, 5); // 80%
+ // Hoist a spill to outer loop if there are multiple dependents (it
+ // can be beneficial if more than one dependents are hoisted) or
+ // if DepSV (the hoisting source) is hotter than SV (the hoisting
+ // destination) (we add a 80% margin to bias a little towards
+ // loop depth).
+ bool HoistCondition =
+ (MBFI.getBlockFreq(DepSV.SpillMBB) >=
+ (MBFI.getBlockFreq(SV.SpillMBB) * MarginProb)) ||
+ Deps->size() > 1;
+
if ((Loops.getLoopDepth(DepSV.SpillMBB) > SpillDepth) &&
+ HoistCondition &&
(!DepSVI->first->isPHIDef() ||
MDT.dominates(SV.SpillMBB, DepSV.SpillMBB))) {
Changed = true;
@@ -476,7 +492,7 @@ MachineInstr *InlineSpiller::traceSiblingValue(unsigned UseReg, VNInfo *UseVNI,
// Check if a cached value already exists.
SibValueMap::iterator SVI;
bool Inserted;
- tie(SVI, Inserted) =
+ std::tie(SVI, Inserted) =
SibValues.insert(std::make_pair(UseVNI, SibValueInfo(UseReg, UseVNI)));
if (!Inserted) {
DEBUG(dbgs() << "Cached value " << PrintReg(UseReg) << ':'
@@ -495,7 +511,7 @@ MachineInstr *InlineSpiller::traceSiblingValue(unsigned UseReg, VNInfo *UseVNI,
do {
unsigned Reg;
VNInfo *VNI;
- tie(Reg, VNI) = WorkList.pop_back_val();
+ std::tie(Reg, VNI) = WorkList.pop_back_val();
DEBUG(dbgs() << " " << PrintReg(Reg) << ':' << VNI->id << '@' << VNI->def
<< ":\t");
@@ -554,7 +570,7 @@ MachineInstr *InlineSpiller::traceSiblingValue(unsigned UseReg, VNInfo *UseVNI,
for (unsigned i = 0, e = NonPHIs.size(); i != e; ++i) {
VNInfo *NonPHI = NonPHIs[i];
// Known value? Try an insertion.
- tie(SVI, Inserted) =
+ std::tie(SVI, Inserted) =
SibValues.insert(std::make_pair(NonPHI, SibValueInfo(Reg, NonPHI)));
// Add all the PHIs as dependents of NonPHI.
for (unsigned pi = 0, pe = PHIs.size(); pi != pe; ++pi)
@@ -587,8 +603,8 @@ MachineInstr *InlineSpiller::traceSiblingValue(unsigned UseReg, VNInfo *UseVNI,
<< SrcVNI->id << '@' << SrcVNI->def
<< " kill=" << unsigned(SVI->second.KillsSource) << '\n');
// Known sibling source value? Try an insertion.
- tie(SVI, Inserted) = SibValues.insert(std::make_pair(SrcVNI,
- SibValueInfo(SrcReg, SrcVNI)));
+ std::tie(SVI, Inserted) = SibValues.insert(
+ std::make_pair(SrcVNI, SibValueInfo(SrcReg, SrcVNI)));
// This is the first time we see Src, add it to the worklist.
if (Inserted)
WorkList.push_back(std::make_pair(SrcReg, SrcVNI));
@@ -745,7 +761,7 @@ void InlineSpiller::eliminateRedundantSpills(LiveInterval &SLI, VNInfo *VNI) {
do {
LiveInterval *LI;
- tie(LI, VNI) = WorkList.pop_back_val();
+ std::tie(LI, VNI) = WorkList.pop_back_val();
unsigned Reg = LI->reg;
DEBUG(dbgs() << "Checking redundant spills for "
<< VNI->id << '@' << VNI->def << " in " << *LI << '\n');
@@ -759,8 +775,10 @@ void InlineSpiller::eliminateRedundantSpills(LiveInterval &SLI, VNInfo *VNI) {
DEBUG(dbgs() << "Merged to stack int: " << *StackInt << '\n');
// Find all spills and copies of VNI.
- for (MachineRegisterInfo::use_nodbg_iterator UI = MRI.use_nodbg_begin(Reg);
- MachineInstr *MI = UI.skipInstruction();) {
+ for (MachineRegisterInfo::use_instr_nodbg_iterator
+ UI = MRI.use_instr_nodbg_begin(Reg), E = MRI.use_instr_nodbg_end();
+ UI != E; ) {
+ MachineInstr *MI = &*(UI++);
if (!MI->isCopy() && !MI->mayStore())
continue;
SlotIndex Idx = LIS.getInstructionIndex(MI);
@@ -804,7 +822,7 @@ void InlineSpiller::markValueUsed(LiveInterval *LI, VNInfo *VNI) {
SmallVector<std::pair<LiveInterval*, VNInfo*>, 8> WorkList;
WorkList.push_back(std::make_pair(LI, VNI));
do {
- tie(LI, VNI) = WorkList.pop_back_val();
+ std::tie(LI, VNI) = WorkList.pop_back_val();
if (!UsedValues.insert(VNI))
continue;
@@ -920,10 +938,12 @@ void InlineSpiller::reMaterializeAll() {
for (unsigned i = 0, e = RegsToSpill.size(); i != e; ++i) {
unsigned Reg = RegsToSpill[i];
LiveInterval &LI = LIS.getInterval(Reg);
- for (MachineRegisterInfo::use_nodbg_iterator
- RI = MRI.use_nodbg_begin(Reg);
- MachineInstr *MI = RI.skipBundle();)
+ for (MachineRegisterInfo::use_bundle_nodbg_iterator
+ RI = MRI.use_bundle_nodbg_begin(Reg), E = MRI.use_bundle_nodbg_end();
+ RI != E; ) {
+ MachineInstr *MI = &*(RI++);
anyRemat |= reMaterializeFor(LI, MI);
+ }
}
if (!anyRemat)
return;
@@ -1014,7 +1034,7 @@ static void dumpMachineInstrRangeWithSlotIndex(MachineBasicBlock::iterator B,
char NextLine = '\n';
char SlotIndent = '\t';
- if (llvm::next(B) == E) {
+ if (std::next(B) == E) {
NextLine = ' ';
SlotIndent = ' ';
}
@@ -1098,12 +1118,11 @@ foldMemoryOperand(ArrayRef<std::pair<MachineInstr*, unsigned> > Ops,
MRI.isReserved(Reg)) {
continue;
}
+ // Skip non-Defs, including undef uses and internal reads.
+ if (MO->isUse())
+ continue;
MIBundleOperands::PhysRegInfo RI =
MIBundleOperands(FoldMI).analyzePhysReg(Reg, &TRI);
- if (MO->readsReg()) {
- assert(RI.Reads && "Cannot fold physreg reader");
- continue;
- }
if (RI.Defines)
continue;
// FoldMI does not define this physreg. Remove the LI segment.
@@ -1172,12 +1191,12 @@ void InlineSpiller::insertSpill(unsigned NewVReg, bool isKill,
MachineBasicBlock &MBB = *MI->getParent();
MachineInstrSpan MIS(MI);
- TII.storeRegToStackSlot(MBB, llvm::next(MI), NewVReg, isKill, StackSlot,
+ TII.storeRegToStackSlot(MBB, std::next(MI), NewVReg, isKill, StackSlot,
MRI.getRegClass(NewVReg), &TRI);
- LIS.InsertMachineInstrRangeInMaps(llvm::next(MI), MIS.end());
+ LIS.InsertMachineInstrRangeInMaps(std::next(MI), MIS.end());
- DEBUG(dumpMachineInstrRangeWithSlotIndex(llvm::next(MI), MIS.end(), LIS,
+ DEBUG(dumpMachineInstrRangeWithSlotIndex(std::next(MI), MIS.end(), LIS,
"spill"));
++NumSpills;
}
@@ -1188,8 +1207,10 @@ void InlineSpiller::spillAroundUses(unsigned Reg) {
LiveInterval &OldLI = LIS.getInterval(Reg);
// Iterate over instructions using Reg.
- for (MachineRegisterInfo::reg_iterator RegI = MRI.reg_begin(Reg);
- MachineInstr *MI = RegI.skipBundle();) {
+ for (MachineRegisterInfo::reg_bundle_iterator
+ RegI = MRI.reg_bundle_begin(Reg), E = MRI.reg_bundle_end();
+ RegI != E; ) {
+ MachineInstr *MI = &*(RegI++);
// Debug values are not allowed to affect codegen.
if (MI->isDebugValue()) {
@@ -1314,8 +1335,10 @@ void InlineSpiller::spillAll() {
// Finally delete the SnippetCopies.
for (unsigned i = 0, e = RegsToSpill.size(); i != e; ++i) {
- for (MachineRegisterInfo::reg_iterator RI = MRI.reg_begin(RegsToSpill[i]);
- MachineInstr *MI = RI.skipInstruction();) {
+ for (MachineRegisterInfo::reg_instr_iterator
+ RI = MRI.reg_instr_begin(RegsToSpill[i]), E = MRI.reg_instr_end();
+ RI != E; ) {
+ MachineInstr *MI = &*(RI++);
assert(SnippetCopies.count(MI) && "Remaining use wasn't a snippet copy");
// FIXME: Do this with a LiveRangeEdit callback.
LIS.RemoveMachineInstrFromMaps(MI);
generated by cgit v1.2.3 (git 2.25.1) at 2025-07-13 12:31:52 +0000