Make BreakAntiDependencies' SUnits argument const, and make the Begin

and End arguments by-value rather than by-reference.

llvm-svn: 101830
This commit is contained in:
Dan Gohman 2010-04-19 23:11:58 +00:00
parent 2d0dca9099
commit 60e18d1d07
5 changed files with 42 additions and 41 deletions

View File

@ -281,9 +281,9 @@ void AggressiveAntiDepBreaker::GetPassthruRegs(MachineInstr *MI,
/// AntiDepEdges - Return in Edges the anti- and output- dependencies
/// in SU that we want to consider for breaking.
static void AntiDepEdges(SUnit *SU, std::vector<SDep*>& Edges) {
static void AntiDepEdges(const SUnit *SU, std::vector<const SDep*>& Edges) {
SmallSet<unsigned, 4> RegSet;
for (SUnit::pred_iterator P = SU->Preds.begin(), PE = SU->Preds.end();
for (SUnit::const_pred_iterator P = SU->Preds.begin(), PE = SU->Preds.end();
P != PE; ++P) {
if ((P->getKind() == SDep::Anti) || (P->getKind() == SDep::Output)) {
unsigned Reg = P->getReg();
@ -297,14 +297,14 @@ static void AntiDepEdges(SUnit *SU, std::vector<SDep*>& Edges) {
/// CriticalPathStep - Return the next SUnit after SU on the bottom-up
/// critical path.
static SUnit *CriticalPathStep(SUnit *SU) {
SDep *Next = 0;
static const SUnit *CriticalPathStep(const SUnit *SU) {
const SDep *Next = 0;
unsigned NextDepth = 0;
// Find the predecessor edge with the greatest depth.
if (SU != 0) {
for (SUnit::pred_iterator P = SU->Preds.begin(), PE = SU->Preds.end();
for (SUnit::const_pred_iterator P = SU->Preds.begin(), PE = SU->Preds.end();
P != PE; ++P) {
SUnit *PredSU = P->getSUnit();
const SUnit *PredSU = P->getSUnit();
unsigned PredLatency = P->getLatency();
unsigned PredTotalLatency = PredSU->getDepth() + PredLatency;
// In the case of a latency tie, prefer an anti-dependency edge over
@ -703,9 +703,9 @@ bool AggressiveAntiDepBreaker::FindSuitableFreeRegisters(
/// ScheduleDAG and break them by renaming registers.
///
unsigned AggressiveAntiDepBreaker::BreakAntiDependencies(
std::vector<SUnit>& SUnits,
MachineBasicBlock::iterator& Begin,
MachineBasicBlock::iterator& End,
const std::vector<SUnit>& SUnits,
MachineBasicBlock::iterator Begin,
MachineBasicBlock::iterator End,
unsigned InsertPosIndex) {
unsigned *KillIndices = State->GetKillIndices();
unsigned *DefIndices = State->GetDefIndices();
@ -720,20 +720,21 @@ unsigned AggressiveAntiDepBreaker::BreakAntiDependencies(
RenameOrderType RenameOrder;
// ...need a map from MI to SUnit.
std::map<MachineInstr *, SUnit *> MISUnitMap;
std::map<MachineInstr *, const SUnit *> MISUnitMap;
for (unsigned i = 0, e = SUnits.size(); i != e; ++i) {
SUnit *SU = &SUnits[i];
MISUnitMap.insert(std::pair<MachineInstr *, SUnit *>(SU->getInstr(), SU));
const SUnit *SU = &SUnits[i];
MISUnitMap.insert(std::pair<MachineInstr *, const SUnit *>(SU->getInstr(),
SU));
}
// Track progress along the critical path through the SUnit graph as
// we walk the instructions. This is needed for regclasses that only
// break critical-path anti-dependencies.
SUnit *CriticalPathSU = 0;
const SUnit *CriticalPathSU = 0;
MachineInstr *CriticalPathMI = 0;
if (CriticalPathSet.any()) {
for (unsigned i = 0, e = SUnits.size(); i != e; ++i) {
SUnit *SU = &SUnits[i];
const SUnit *SU = &SUnits[i];
if (!CriticalPathSU ||
((SU->getDepth() + SU->Latency) >
(CriticalPathSU->getDepth() + CriticalPathSU->Latency))) {
@ -774,8 +775,8 @@ unsigned AggressiveAntiDepBreaker::BreakAntiDependencies(
// The dependence edges that represent anti- and output-
// dependencies that are candidates for breaking.
std::vector<SDep*> Edges;
SUnit *PathSU = MISUnitMap[MI];
std::vector<const SDep *> Edges;
const SUnit *PathSU = MISUnitMap[MI];
AntiDepEdges(PathSU, Edges);
// If MI is not on the critical path, then we don't rename
@ -793,7 +794,7 @@ unsigned AggressiveAntiDepBreaker::BreakAntiDependencies(
if (!MI->isKill()) {
// Attempt to break each anti-dependency...
for (unsigned i = 0, e = Edges.size(); i != e; ++i) {
SDep *Edge = Edges[i];
const SDep *Edge = Edges[i];
SUnit *NextSU = Edge->getSUnit();
if ((Edge->getKind() != SDep::Anti) &&
@ -837,7 +838,7 @@ unsigned AggressiveAntiDepBreaker::BreakAntiDependencies(
// Also, if there are dependencies on other SUnits with the
// same register as the anti-dependency, don't attempt to
// break it.
for (SUnit::pred_iterator P = PathSU->Preds.begin(),
for (SUnit::const_pred_iterator P = PathSU->Preds.begin(),
PE = PathSU->Preds.end(); P != PE; ++P) {
if (P->getSUnit() == NextSU ?
(P->getKind() != SDep::Anti || P->getReg() != AntiDepReg) :
@ -846,7 +847,7 @@ unsigned AggressiveAntiDepBreaker::BreakAntiDependencies(
break;
}
}
for (SUnit::pred_iterator P = PathSU->Preds.begin(),
for (SUnit::const_pred_iterator P = PathSU->Preds.begin(),
PE = PathSU->Preds.end(); P != PE; ++P) {
if ((P->getSUnit() == NextSU) && (P->getKind() != SDep::Anti) &&
(P->getKind() != SDep::Output)) {

View File

@ -142,9 +142,9 @@ namespace llvm {
/// path
/// of the ScheduleDAG and break them by renaming registers.
///
unsigned BreakAntiDependencies(std::vector<SUnit>& SUnits,
MachineBasicBlock::iterator& Begin,
MachineBasicBlock::iterator& End,
unsigned BreakAntiDependencies(const std::vector<SUnit>& SUnits,
MachineBasicBlock::iterator Begin,
MachineBasicBlock::iterator End,
unsigned InsertPosIndex);
/// Observe - Update liveness information to account for the current

View File

@ -39,9 +39,9 @@ public:
/// basic-block region and break them by renaming registers. Return
/// the number of anti-dependencies broken.
///
virtual unsigned BreakAntiDependencies(std::vector<SUnit>& SUnits,
MachineBasicBlock::iterator& Begin,
MachineBasicBlock::iterator& End,
virtual unsigned BreakAntiDependencies(const std::vector<SUnit>& SUnits,
MachineBasicBlock::iterator Begin,
MachineBasicBlock::iterator End,
unsigned InsertPosIndex) =0;
/// Observe - Update liveness information to account for the current

View File

@ -143,13 +143,13 @@ void CriticalAntiDepBreaker::Observe(MachineInstr *MI, unsigned Count,
/// CriticalPathStep - Return the next SUnit after SU on the bottom-up
/// critical path.
static SDep *CriticalPathStep(SUnit *SU) {
SDep *Next = 0;
static const SDep *CriticalPathStep(const SUnit *SU) {
const SDep *Next = 0;
unsigned NextDepth = 0;
// Find the predecessor edge with the greatest depth.
for (SUnit::pred_iterator P = SU->Preds.begin(), PE = SU->Preds.end();
for (SUnit::const_pred_iterator P = SU->Preds.begin(), PE = SU->Preds.end();
P != PE; ++P) {
SUnit *PredSU = P->getSUnit();
const SUnit *PredSU = P->getSUnit();
unsigned PredLatency = P->getLatency();
unsigned PredTotalLatency = PredSU->getDepth() + PredLatency;
// In the case of a latency tie, prefer an anti-dependency edge over
@ -326,18 +326,18 @@ CriticalAntiDepBreaker::findSuitableFreeRegister(MachineInstr *MI,
}
unsigned CriticalAntiDepBreaker::
BreakAntiDependencies(std::vector<SUnit>& SUnits,
MachineBasicBlock::iterator& Begin,
MachineBasicBlock::iterator& End,
BreakAntiDependencies(const std::vector<SUnit>& SUnits,
MachineBasicBlock::iterator Begin,
MachineBasicBlock::iterator End,
unsigned InsertPosIndex) {
// The code below assumes that there is at least one instruction,
// so just duck out immediately if the block is empty.
if (SUnits.empty()) return 0;
// Find the node at the bottom of the critical path.
SUnit *Max = 0;
const SUnit *Max = 0;
for (unsigned i = 0, e = SUnits.size(); i != e; ++i) {
SUnit *SU = &SUnits[i];
const SUnit *SU = &SUnits[i];
if (!Max || SU->getDepth() + SU->Latency > Max->getDepth() + Max->Latency)
Max = SU;
}
@ -357,7 +357,7 @@ BreakAntiDependencies(std::vector<SUnit>& SUnits,
// Track progress along the critical path through the SUnit graph as we walk
// the instructions.
SUnit *CriticalPathSU = Max;
const SUnit *CriticalPathSU = Max;
MachineInstr *CriticalPathMI = CriticalPathSU->getInstr();
// Consider this pattern:
@ -429,8 +429,8 @@ BreakAntiDependencies(std::vector<SUnit>& SUnits,
// the anti-dependencies in an instruction in order to be effective.
unsigned AntiDepReg = 0;
if (MI == CriticalPathMI) {
if (SDep *Edge = CriticalPathStep(CriticalPathSU)) {
SUnit *NextSU = Edge->getSUnit();
if (const SDep *Edge = CriticalPathStep(CriticalPathSU)) {
const SUnit *NextSU = Edge->getSUnit();
// Only consider anti-dependence edges.
if (Edge->getKind() == SDep::Anti) {
@ -452,7 +452,7 @@ BreakAntiDependencies(std::vector<SUnit>& SUnits,
// Also, if there are dependencies on other SUnits with the
// same register as the anti-dependency, don't attempt to
// break it.
for (SUnit::pred_iterator P = CriticalPathSU->Preds.begin(),
for (SUnit::const_pred_iterator P = CriticalPathSU->Preds.begin(),
PE = CriticalPathSU->Preds.end(); P != PE; ++P)
if (P->getSUnit() == NextSU ?
(P->getKind() != SDep::Anti || P->getReg() != AntiDepReg) :

View File

@ -72,9 +72,9 @@ namespace llvm {
/// path
/// of the ScheduleDAG and break them by renaming registers.
///
unsigned BreakAntiDependencies(std::vector<SUnit>& SUnits,
MachineBasicBlock::iterator& Begin,
MachineBasicBlock::iterator& End,
unsigned BreakAntiDependencies(const std::vector<SUnit>& SUnits,
MachineBasicBlock::iterator Begin,
MachineBasicBlock::iterator End,
unsigned InsertPosIndex);
/// Observe - Update liveness information to account for the current