//
//===----------------------------------------------------------------------===//
-#define DEBUG_TYPE "regalloc"
#include "Spiller.h"
#include "llvm/ADT/SetVector.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/CodeGen/LiveRangeEdit.h"
#include "llvm/CodeGen/LiveStackAnalysis.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"
using namespace llvm;
+#define DEBUG_TYPE "regalloc"
+
STATISTIC(NumSpilledRanges, "Number of spilled live ranges");
STATISTIC(NumSnippets, "Number of spilled snippets");
STATISTIC(NumSpills, "Number of spills inserted");
SibValueInfo(unsigned Reg, VNInfo *VNI)
: AllDefsAreReloads(true), DefByOrigPHI(false), KillsSource(false),
- SpillReg(Reg), SpillVNI(VNI), SpillMBB(0), DefMI(0) {}
+ SpillReg(Reg), SpillVNI(VNI), SpillMBB(nullptr), DefMI(nullptr) {}
// Returns true when a def has been found.
bool hasDef() const { return DefByOrigPHI || DefMI; }
bool isSibling(unsigned Reg);
MachineInstr *traceSiblingValue(unsigned, VNInfo*, VNInfo*);
- void propagateSiblingValue(SibValueMap::iterator, VNInfo *VNI = 0);
+ void propagateSiblingValue(SibValueMap::iterator, VNInfo *VNI = nullptr);
void analyzeSiblingValues();
bool hoistSpill(LiveInterval &SpillLI, MachineInstr *CopyMI);
bool coalesceStackAccess(MachineInstr *MI, unsigned Reg);
bool foldMemoryOperand(ArrayRef<std::pair<MachineInstr*, unsigned> >,
- MachineInstr *LoadMI = 0);
+ MachineInstr *LoadMI = nullptr);
void insertReload(unsigned VReg, SlotIndex, MachineBasicBlock::iterator MI);
void insertSpill(unsigned VReg, bool isKill, MachineBasicBlock::iterator MI);
if (SnipLI.getNumValNums() > 2 || !LIS.intervalIsInOneMBB(SnipLI))
return false;
- MachineInstr *UseMI = 0;
+ MachineInstr *UseMI = nullptr;
// 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))
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;
do {
SVI = WorkList.pop_back_val();
TinyPtrVector<VNInfo*> *Deps = VNI ? &FirstDeps : &SVI->second.Deps;
- VNI = 0;
+ VNI = nullptr;
SibValueInfo &SV = SVI->second;
if (!SV.SpillMBB)
// 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;
VNInfo *VNI = *VI;
if (VNI->isUnused())
continue;
- MachineInstr *DefMI = 0;
+ MachineInstr *DefMI = nullptr;
if (!VNI->isPHIDef()) {
DefMI = LIS.getInstructionFromIndex(VNI->def);
assert(DefMI && "No defining instruction");
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);
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;
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()) {
// 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);
// Share a stack slot among all descendants of Original.
Original = VRM.getOriginal(edit.getReg());
StackSlot = VRM.getStackSlot(Original);
- StackInt = 0;
+ StackInt = nullptr;
DEBUG(dbgs() << "Inline spilling "
<< MRI.getRegClass(edit.getReg())->getName()
projects / oota-llvm.git / blobdiff