#include "llvm/CodeGen/MachineBasicBlock.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineInstr.h"
-#include "llvm/Target/TargetInstrInfo.h"
-#include "llvm/Target/TargetMachine.h"
-#include "llvm/Target/TargetRegisterInfo.h"
+#include "llvm/CodeGen/RegisterClassInfo.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/raw_ostream.h"
+#include "llvm/Target/TargetInstrInfo.h"
+#include "llvm/Target/TargetMachine.h"
+#include "llvm/Target/TargetRegisterInfo.h"
using namespace llvm;
// If DebugDiv > 0 then only break antidep with (ID % DebugDiv) == DebugMod
AggressiveAntiDepState::AggressiveAntiDepState(const unsigned TargetRegs,
MachineBasicBlock *BB) :
- NumTargetRegs(TargetRegs), GroupNodes(TargetRegs, 0) {
-
+ NumTargetRegs(TargetRegs), GroupNodes(TargetRegs, 0),
+ GroupNodeIndices(TargetRegs, 0),
+ KillIndices(TargetRegs, 0),
+ DefIndices(TargetRegs, 0)
+{
const unsigned BBSize = BB->size();
for (unsigned i = 0; i < NumTargetRegs; ++i) {
// Initialize all registers to be in their own group. Initially we
}
}
-unsigned AggressiveAntiDepState::GetGroup(unsigned Reg)
-{
+unsigned AggressiveAntiDepState::GetGroup(unsigned Reg) {
unsigned Node = GroupNodeIndices[Reg];
while (GroupNodes[Node] != Node)
Node = GroupNodes[Node];
AggressiveAntiDepBreaker::
AggressiveAntiDepBreaker(MachineFunction& MFi,
- TargetSubtarget::RegClassVector& CriticalPathRCs) :
+ const RegisterClassInfo &RCI,
+ TargetSubtargetInfo::RegClassVector& CriticalPathRCs) :
AntiDepBreaker(), MF(MFi),
MRI(MF.getRegInfo()),
+ TII(MF.getTarget().getInstrInfo()),
TRI(MF.getTarget().getRegisterInfo()),
- AllocatableSet(TRI->getAllocatableSet(MF)),
+ RegClassInfo(RCI),
State(NULL) {
/* Collect a bitset of all registers that are only broken if they
are on the critical path. */
assert(State == NULL);
State = new AggressiveAntiDepState(TRI->getNumRegs(), BB);
- bool IsReturnBlock = (!BB->empty() && BB->back().getDesc().isReturn());
- unsigned *KillIndices = State->GetKillIndices();
- unsigned *DefIndices = State->GetDefIndices();
+ bool IsReturnBlock = (!BB->empty() && BB->back().isReturn());
+ std::vector<unsigned> &KillIndices = State->GetKillIndices();
+ std::vector<unsigned> &DefIndices = State->GetDefIndices();
- // Determine the live-out physregs for this block.
- if (IsReturnBlock) {
- // In a return block, examine the function live-out regs.
- for (MachineRegisterInfo::liveout_iterator I = MRI.liveout_begin(),
- E = MRI.liveout_end(); I != E; ++I) {
- unsigned Reg = *I;
- State->UnionGroups(Reg, 0);
- KillIndices[Reg] = BB->size();
- DefIndices[Reg] = ~0u;
- // Repeat, for all aliases.
- for (const unsigned *Alias = TRI->getAliasSet(Reg); *Alias; ++Alias) {
- unsigned AliasReg = *Alias;
- State->UnionGroups(AliasReg, 0);
- KillIndices[AliasReg] = BB->size();
- DefIndices[AliasReg] = ~0u;
- }
- }
- } else {
- // In a non-return block, examine the live-in regs of all successors.
- for (MachineBasicBlock::succ_iterator SI = BB->succ_begin(),
+ // Examine the live-in regs of all successors.
+ for (MachineBasicBlock::succ_iterator SI = BB->succ_begin(),
SE = BB->succ_end(); SI != SE; ++SI)
- for (MachineBasicBlock::livein_iterator I = (*SI)->livein_begin(),
+ for (MachineBasicBlock::livein_iterator I = (*SI)->livein_begin(),
E = (*SI)->livein_end(); I != E; ++I) {
- unsigned Reg = *I;
+ for (MCRegAliasIterator AI(*I, TRI, true); AI.isValid(); ++AI) {
+ unsigned Reg = *AI;
State->UnionGroups(Reg, 0);
KillIndices[Reg] = BB->size();
DefIndices[Reg] = ~0u;
- // Repeat, for all aliases.
- for (const unsigned *Alias = TRI->getAliasSet(Reg); *Alias; ++Alias) {
- unsigned AliasReg = *Alias;
- State->UnionGroups(AliasReg, 0);
- KillIndices[AliasReg] = BB->size();
- DefIndices[AliasReg] = ~0u;
- }
}
- }
+ }
// Mark live-out callee-saved registers. In a return block this is
// all callee-saved registers. In non-return this is any
// callee-saved register that is not saved in the prolog.
const MachineFrameInfo *MFI = MF.getFrameInfo();
BitVector Pristine = MFI->getPristineRegs(BB);
- for (const unsigned *I = TRI->getCalleeSavedRegs(); *I; ++I) {
+ for (const uint16_t *I = TRI->getCalleeSavedRegs(&MF); *I; ++I) {
unsigned Reg = *I;
if (!IsReturnBlock && !Pristine.test(Reg)) continue;
- State->UnionGroups(Reg, 0);
- KillIndices[Reg] = BB->size();
- DefIndices[Reg] = ~0u;
- // Repeat, for all aliases.
- for (const unsigned *Alias = TRI->getAliasSet(Reg); *Alias; ++Alias) {
- unsigned AliasReg = *Alias;
+ for (MCRegAliasIterator AI(Reg, TRI, true); AI.isValid(); ++AI) {
+ unsigned AliasReg = *AI;
State->UnionGroups(AliasReg, 0);
KillIndices[AliasReg] = BB->size();
DefIndices[AliasReg] = ~0u;
DEBUG(MI->dump());
DEBUG(dbgs() << "\tRegs:");
- unsigned *DefIndices = State->GetDefIndices();
+ std::vector<unsigned> &DefIndices = State->GetDefIndices();
for (unsigned Reg = 0; Reg != TRI->getNumRegs(); ++Reg) {
// If Reg is current live, then mark that it can't be renamed as
// we don't know the extent of its live-range anymore (now that it
if ((MO.isDef() && MI->isRegTiedToUseOperand(i)) ||
IsImplicitDefUse(MI, MO)) {
const unsigned Reg = MO.getReg();
- PassthruRegs.insert(Reg);
- for (const unsigned *Subreg = TRI->getSubRegisters(Reg);
- *Subreg; ++Subreg) {
- PassthruRegs.insert(*Subreg);
- }
+ for (MCSubRegIterator SubRegs(Reg, TRI, /*IncludeSelf=*/true);
+ SubRegs.isValid(); ++SubRegs)
+ PassthruRegs.insert(*SubRegs);
}
}
}
const char *tag,
const char *header,
const char *footer) {
- unsigned *KillIndices = State->GetKillIndices();
- unsigned *DefIndices = State->GetDefIndices();
+ std::vector<unsigned> &KillIndices = State->GetKillIndices();
+ std::vector<unsigned> &DefIndices = State->GetDefIndices();
std::multimap<unsigned, AggressiveAntiDepState::RegisterReference>&
RegRefs = State->GetRegRefs();
DEBUG(dbgs() << "->g" << State->GetGroup(Reg) << tag);
}
// Repeat for subregisters.
- for (const unsigned *Subreg = TRI->getSubRegisters(Reg);
- *Subreg; ++Subreg) {
- unsigned SubregReg = *Subreg;
+ for (MCSubRegIterator SubRegs(Reg, TRI); SubRegs.isValid(); ++SubRegs) {
+ unsigned SubregReg = *SubRegs;
if (!State->IsLive(SubregReg)) {
KillIndices[SubregReg] = KillIdx;
DefIndices[SubregReg] = ~0u;
void AggressiveAntiDepBreaker::PrescanInstruction(MachineInstr *MI,
unsigned Count,
std::set<unsigned>& PassthruRegs) {
- unsigned *DefIndices = State->GetDefIndices();
+ std::vector<unsigned> &DefIndices = State->GetDefIndices();
std::multimap<unsigned, AggressiveAntiDepState::RegisterReference>&
RegRefs = State->GetRegRefs();
// Handle dead defs by simulating a last-use of the register just
- // after the def. A dead def can occur because the def is truely
+ // after the def. A dead def can occur because the def is truly
// dead, or because only a subregister is live at the def. If we
// don't do this the dead def will be incorrectly merged into the
// previous def.
// If MI's defs have a special allocation requirement, don't allow
// any def registers to be changed. Also assume all registers
// defined in a call must not be changed (ABI).
- if (MI->getDesc().isCall() || MI->getDesc().hasExtraDefRegAllocReq()) {
+ if (MI->isCall() || MI->hasExtraDefRegAllocReq() ||
+ TII->isPredicated(MI)) {
DEBUG(if (State->GetGroup(Reg) != 0) dbgs() << "->g0(alloc-req)");
State->UnionGroups(Reg, 0);
}
// Any aliased that are live at this point are completely or
// partially defined here, so group those aliases with Reg.
- for (const unsigned *Alias = TRI->getAliasSet(Reg); *Alias; ++Alias) {
- unsigned AliasReg = *Alias;
+ for (MCRegAliasIterator AI(Reg, TRI, false); AI.isValid(); ++AI) {
+ unsigned AliasReg = *AI;
if (State->IsLive(AliasReg)) {
State->UnionGroups(Reg, AliasReg);
DEBUG(dbgs() << "->g" << State->GetGroup(Reg) << "(via " <<
// Note register reference...
const TargetRegisterClass *RC = NULL;
if (i < MI->getDesc().getNumOperands())
- RC = MI->getDesc().OpInfo[i].getRegClass(TRI);
+ RC = TII->getRegClass(MI->getDesc(), i, TRI, MF);
AggressiveAntiDepState::RegisterReference RR = { &MO, RC };
RegRefs.insert(std::make_pair(Reg, RR));
}
continue;
// Update def for Reg and aliases.
- DefIndices[Reg] = Count;
- for (const unsigned *Alias = TRI->getAliasSet(Reg);
- *Alias; ++Alias) {
- unsigned AliasReg = *Alias;
- DefIndices[AliasReg] = Count;
- }
+ for (MCRegAliasIterator AI(Reg, TRI, true); AI.isValid(); ++AI)
+ DefIndices[*AI] = Count;
}
}
std::multimap<unsigned, AggressiveAntiDepState::RegisterReference>&
RegRefs = State->GetRegRefs();
+ // If MI's uses have special allocation requirement, don't allow
+ // any use registers to be changed. Also assume all registers
+ // used in a call must not be changed (ABI).
+ // FIXME: The issue with predicated instruction is more complex. We are being
+ // conservatively here because the kill markers cannot be trusted after
+ // if-conversion:
+ // %R6<def> = LDR %SP, %reg0, 92, pred:14, pred:%reg0; mem:LD4[FixedStack14]
+ // ...
+ // STR %R0, %R6<kill>, %reg0, 0, pred:0, pred:%CPSR; mem:ST4[%395]
+ // %R6<def> = LDR %SP, %reg0, 100, pred:0, pred:%CPSR; mem:LD4[FixedStack12]
+ // STR %R0, %R6<kill>, %reg0, 0, pred:14, pred:%reg0; mem:ST4[%396](align=8)
+ //
+ // The first R6 kill is not really a kill since it's killed by a predicated
+ // instruction which may not be executed. The second R6 def may or may not
+ // re-define R6 so it's not safe to change it since the last R6 use cannot be
+ // changed.
+ bool Special = MI->isCall() ||
+ MI->hasExtraSrcRegAllocReq() ||
+ TII->isPredicated(MI);
+
// Scan the register uses for this instruction and update
// live-ranges, groups and RegRefs.
for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
// for the register.
HandleLastUse(Reg, Count, "(last-use)");
- // If MI's uses have special allocation requirement, don't allow
- // any use registers to be changed. Also assume all registers
- // used in a call must not be changed (ABI).
- if (MI->getDesc().isCall() || MI->getDesc().hasExtraSrcRegAllocReq()) {
+ if (Special) {
DEBUG(if (State->GetGroup(Reg) != 0) dbgs() << "->g0(alloc-req)");
State->UnionGroups(Reg, 0);
}
// Note register reference...
const TargetRegisterClass *RC = NULL;
if (i < MI->getDesc().getNumOperands())
- RC = MI->getDesc().OpInfo[i].getRegClass(TRI);
+ RC = TII->getRegClass(MI->getDesc(), i, TRI, MF);
AggressiveAntiDepState::RegisterReference RR = { &MO, RC };
RegRefs.insert(std::make_pair(Reg, RR));
}
unsigned AntiDepGroupIndex,
RenameOrderType& RenameOrder,
std::map<unsigned, unsigned> &RenameMap) {
- unsigned *KillIndices = State->GetKillIndices();
- unsigned *DefIndices = State->GetDefIndices();
+ std::vector<unsigned> &KillIndices = State->GetKillIndices();
+ std::vector<unsigned> &DefIndices = State->GetDefIndices();
std::multimap<unsigned, AggressiveAntiDepState::RegisterReference>&
RegRefs = State->GetRegRefs();
// order. If that register is available, and the corresponding
// registers are available for the other group subregisters, then we
// can use those registers to rename.
+
+ // FIXME: Using getMinimalPhysRegClass is very conservative. We should
+ // check every use of the register and find the largest register class
+ // that can be used in all of them.
const TargetRegisterClass *SuperRC =
- TRI->getPhysicalRegisterRegClass(SuperReg, MVT::Other);
+ TRI->getMinimalPhysRegClass(SuperReg, MVT::Other);
- const TargetRegisterClass::iterator RB = SuperRC->allocation_order_begin(MF);
- const TargetRegisterClass::iterator RE = SuperRC->allocation_order_end(MF);
- if (RB == RE) {
+ ArrayRef<MCPhysReg> Order = RegClassInfo.getOrder(SuperRC);
+ if (Order.empty()) {
DEBUG(dbgs() << "\tEmpty Super Regclass!!\n");
return false;
}
DEBUG(dbgs() << "\tFind Registers:");
if (RenameOrder.count(SuperRC) == 0)
- RenameOrder.insert(RenameOrderType::value_type(SuperRC, RE));
+ RenameOrder.insert(RenameOrderType::value_type(SuperRC, Order.size()));
- const TargetRegisterClass::iterator OrigR = RenameOrder[SuperRC];
- const TargetRegisterClass::iterator EndR = ((OrigR == RE) ? RB : OrigR);
- TargetRegisterClass::iterator R = OrigR;
+ unsigned OrigR = RenameOrder[SuperRC];
+ unsigned EndR = ((OrigR == Order.size()) ? 0 : OrigR);
+ unsigned R = OrigR;
do {
- if (R == RB) R = RE;
+ if (R == 0) R = Order.size();
--R;
- const unsigned NewSuperReg = *R;
+ const unsigned NewSuperReg = Order[R];
+ // Don't consider non-allocatable registers
+ if (!MRI.isAllocatable(NewSuperReg)) continue;
// Don't replace a register with itself.
if (NewSuperReg == SuperReg) continue;
goto next_super_reg;
} else {
bool found = false;
- for (const unsigned *Alias = TRI->getAliasSet(NewReg);
- *Alias; ++Alias) {
- unsigned AliasReg = *Alias;
+ for (MCRegAliasIterator AI(NewReg, TRI, false); AI.isValid(); ++AI) {
+ unsigned AliasReg = *AI;
if (State->IsLive(AliasReg) ||
(KillIndices[Reg] > DefIndices[AliasReg])) {
DEBUG(dbgs() << "(alias " << TRI->getName(AliasReg) << " live)");
const std::vector<SUnit>& SUnits,
MachineBasicBlock::iterator Begin,
MachineBasicBlock::iterator End,
- unsigned InsertPosIndex) {
- unsigned *KillIndices = State->GetKillIndices();
- unsigned *DefIndices = State->GetDefIndices();
+ unsigned InsertPosIndex,
+ DbgValueVector &DbgValues) {
+
+ std::vector<unsigned> &KillIndices = State->GetKillIndices();
+ std::vector<unsigned> &DefIndices = State->GetDefIndices();
std::multimap<unsigned, AggressiveAntiDepState::RegisterReference>&
RegRefs = State->GetRegRefs();
I != E; --Count) {
MachineInstr *MI = --I;
+ if (MI->isDebugValue())
+ continue;
+
DEBUG(dbgs() << "Anti: ");
DEBUG(MI->dump());
if (MI == CriticalPathMI) {
CriticalPathSU = CriticalPathStep(CriticalPathSU);
CriticalPathMI = (CriticalPathSU) ? CriticalPathSU->getInstr() : 0;
- } else {
+ } else if (CriticalPathSet.any()) {
ExcludeRegs = &CriticalPathSet;
}
DEBUG(dbgs() << "\tAntidep reg: " << TRI->getName(AntiDepReg));
assert(AntiDepReg != 0 && "Anti-dependence on reg0?");
- if (!AllocatableSet.test(AntiDepReg)) {
+ if (!MRI.isAllocatable(AntiDepReg)) {
// Don't break anti-dependencies on non-allocatable registers.
DEBUG(dbgs() << " (non-allocatable)\n");
continue;
// information related to the anti-dependency register, make
// sure to update that as well.
const SUnit *SU = MISUnitMap[Q->second.Operand->getParent()];
- for (unsigned i = 0, e = SU->DbgInstrList.size() ; i < e ; ++i) {
- MachineInstr *DI = SU->DbgInstrList[i];
- assert (DI->getNumOperands()==3 && DI->getOperand(0).isReg() &&
- DI->getOperand(0).getReg()
- && "Non register dbg_value attached to SUnit!");
- if (DI->getOperand(0).getReg() == AntiDepReg)
- DI->getOperand(0).setReg(NewReg);
- }
+ if (!SU) continue;
+ for (DbgValueVector::iterator DVI = DbgValues.begin(),
+ DVE = DbgValues.end(); DVI != DVE; ++DVI)
+ if (DVI->second == Q->second.Operand->getParent())
+ UpdateDbgValue(DVI->first, AntiDepReg, NewReg);
}
// We just went back in time and modified history; the
projects / oota-llvm.git / blobdiff