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llvm-project/llvm/lib/Analysis/ProfileInfo.cpp

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//===- ProfileInfo.cpp - Profile Info Interface ---------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the abstract ProfileInfo interface, and the default
// "no profile" implementation.
//
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "profile-info"
#include "llvm/Analysis/Passes.h"
#include "llvm/Analysis/ProfileInfo.h"
#include "llvm/CodeGen/MachineBasicBlock.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/Pass.h"
#include "llvm/Support/CFG.h"
#include "llvm/ADT/SmallSet.h"
#include <set>
#include <queue>
#include <limits>
using namespace llvm;
namespace llvm {
template<> char ProfileInfoT<Function,BasicBlock>::ID = 0;
}
// Register the ProfileInfo interface, providing a nice name to refer to.
INITIALIZE_ANALYSIS_GROUP(ProfileInfo, "Profile Information", NoProfileInfo)
namespace llvm {
template <>
ProfileInfoT<MachineFunction, MachineBasicBlock>::ProfileInfoT() {}
template <>
ProfileInfoT<MachineFunction, MachineBasicBlock>::~ProfileInfoT() {}
template <>
ProfileInfoT<Function, BasicBlock>::ProfileInfoT() {
MachineProfile = 0;
}
template <>
ProfileInfoT<Function, BasicBlock>::~ProfileInfoT() {
if (MachineProfile) delete MachineProfile;
}
template<>
char ProfileInfoT<MachineFunction, MachineBasicBlock>::ID = 0;
template<>
const double ProfileInfoT<Function,BasicBlock>::MissingValue = -1;
template<> const
double ProfileInfoT<MachineFunction, MachineBasicBlock>::MissingValue = -1;
template<> double
ProfileInfoT<Function,BasicBlock>::getExecutionCount(const BasicBlock *BB) {
std::map<const Function*, BlockCounts>::iterator J =
BlockInformation.find(BB->getParent());
if (J != BlockInformation.end()) {
BlockCounts::iterator I = J->second.find(BB);
if (I != J->second.end())
return I->second;
}
double Count = MissingValue;
const_pred_iterator PI = pred_begin(BB), PE = pred_end(BB);
// Are there zero predecessors of this block?
if (PI == PE) {
Edge e = getEdge(0, BB);
Count = getEdgeWeight(e);
} else {
// Otherwise, if there are predecessors, the execution count of this block is
// the sum of the edge frequencies from the incoming edges.
std::set<const BasicBlock*> ProcessedPreds;
Count = 0;
for (; PI != PE; ++PI) {
const BasicBlock *P = *PI;
if (ProcessedPreds.insert(P).second) {
double w = getEdgeWeight(getEdge(P, BB));
if (w == MissingValue) {
Count = MissingValue;
break;
}
Count += w;
}
}
}
// If the predecessors did not suffice to get block weight, try successors.
if (Count == MissingValue) {
succ_const_iterator SI = succ_begin(BB), SE = succ_end(BB);
// Are there zero successors of this block?
if (SI == SE) {
Edge e = getEdge(BB,0);
Count = getEdgeWeight(e);
} else {
std::set<const BasicBlock*> ProcessedSuccs;
Count = 0;
for (; SI != SE; ++SI)
if (ProcessedSuccs.insert(*SI).second) {
double w = getEdgeWeight(getEdge(BB, *SI));
if (w == MissingValue) {
Count = MissingValue;
break;
}
Count += w;
}
}
}
if (Count != MissingValue) BlockInformation[BB->getParent()][BB] = Count;
return Count;
}
template<>
double ProfileInfoT<MachineFunction, MachineBasicBlock>::
getExecutionCount(const MachineBasicBlock *MBB) {
std::map<const MachineFunction*, BlockCounts>::iterator J =
BlockInformation.find(MBB->getParent());
if (J != BlockInformation.end()) {
BlockCounts::iterator I = J->second.find(MBB);
if (I != J->second.end())
return I->second;
}
return MissingValue;
}
template<>
double ProfileInfoT<Function,BasicBlock>::getExecutionCount(const Function *F) {
std::map<const Function*, double>::iterator J =
FunctionInformation.find(F);
if (J != FunctionInformation.end())
return J->second;
// isDeclaration() is checked here and not at start of function to allow
// functions without a body still to have a execution count.
if (F->isDeclaration()) return MissingValue;
double Count = getExecutionCount(&F->getEntryBlock());
if (Count != MissingValue) FunctionInformation[F] = Count;
return Count;
}
template<>
double ProfileInfoT<MachineFunction, MachineBasicBlock>::
getExecutionCount(const MachineFunction *MF) {
std::map<const MachineFunction*, double>::iterator J =
FunctionInformation.find(MF);
if (J != FunctionInformation.end())
return J->second;
double Count = getExecutionCount(&MF->front());
if (Count != MissingValue) FunctionInformation[MF] = Count;
return Count;
}
template<>
void ProfileInfoT<Function,BasicBlock>::
setExecutionCount(const BasicBlock *BB, double w) {
DEBUG(dbgs() << "Creating Block " << BB->getName()
<< " (weight: " << format("%.20g",w) << ")\n");
BlockInformation[BB->getParent()][BB] = w;
}
template<>
void ProfileInfoT<MachineFunction, MachineBasicBlock>::
setExecutionCount(const MachineBasicBlock *MBB, double w) {
DEBUG(dbgs() << "Creating Block " << MBB->getBasicBlock()->getName()
<< " (weight: " << format("%.20g",w) << ")\n");
BlockInformation[MBB->getParent()][MBB] = w;
}
template<>
void ProfileInfoT<Function,BasicBlock>::addEdgeWeight(Edge e, double w) {
double oldw = getEdgeWeight(e);
assert (oldw != MissingValue && "Adding weight to Edge with no previous weight");
DEBUG(dbgs() << "Adding to Edge " << e
<< " (new weight: " << format("%.20g",oldw + w) << ")\n");
EdgeInformation[getFunction(e)][e] = oldw + w;
}
template<>
void ProfileInfoT<Function,BasicBlock>::
addExecutionCount(const BasicBlock *BB, double w) {
double oldw = getExecutionCount(BB);
assert (oldw != MissingValue && "Adding weight to Block with no previous weight");
DEBUG(dbgs() << "Adding to Block " << BB->getName()
<< " (new weight: " << format("%.20g",oldw + w) << ")\n");
BlockInformation[BB->getParent()][BB] = oldw + w;
}
template<>
void ProfileInfoT<Function,BasicBlock>::removeBlock(const BasicBlock *BB) {
std::map<const Function*, BlockCounts>::iterator J =
BlockInformation.find(BB->getParent());
if (J == BlockInformation.end()) return;
DEBUG(dbgs() << "Deleting " << BB->getName() << "\n");
J->second.erase(BB);
}
template<>
void ProfileInfoT<Function,BasicBlock>::removeEdge(Edge e) {
std::map<const Function*, EdgeWeights>::iterator J =
EdgeInformation.find(getFunction(e));
if (J == EdgeInformation.end()) return;
DEBUG(dbgs() << "Deleting" << e << "\n");
J->second.erase(e);
}
template<>
void ProfileInfoT<Function,BasicBlock>::
replaceEdge(const Edge &oldedge, const Edge &newedge) {
double w;
if ((w = getEdgeWeight(newedge)) == MissingValue) {
w = getEdgeWeight(oldedge);
DEBUG(dbgs() << "Replacing " << oldedge << " with " << newedge << "\n");
} else {
w += getEdgeWeight(oldedge);
DEBUG(dbgs() << "Adding " << oldedge << " to " << newedge << "\n");
}
setEdgeWeight(newedge,w);
removeEdge(oldedge);
}
template<>
const BasicBlock *ProfileInfoT<Function,BasicBlock>::
GetPath(const BasicBlock *Src, const BasicBlock *Dest,
Path &P, unsigned Mode) {
const BasicBlock *BB = 0;
bool hasFoundPath = false;
std::queue<const BasicBlock *> BFS;
BFS.push(Src);
while(BFS.size() && !hasFoundPath) {
BB = BFS.front();
BFS.pop();
succ_const_iterator Succ = succ_begin(BB), End = succ_end(BB);
if (Succ == End) {
P[0] = BB;
if (Mode & GetPathToExit) {
hasFoundPath = true;
BB = 0;
}
}
for(;Succ != End; ++Succ) {
if (P.find(*Succ) != P.end()) continue;
Edge e = getEdge(BB,*Succ);
if ((Mode & GetPathWithNewEdges) && (getEdgeWeight(e) != MissingValue)) continue;
P[*Succ] = BB;
BFS.push(*Succ);
if ((Mode & GetPathToDest) && *Succ == Dest) {
hasFoundPath = true;
BB = *Succ;
break;
}
if ((Mode & GetPathToValue) && (getExecutionCount(*Succ) != MissingValue)) {
hasFoundPath = true;
BB = *Succ;
break;
}
}
}
return BB;
}
template<>
void ProfileInfoT<Function,BasicBlock>::
divertFlow(const Edge &oldedge, const Edge &newedge) {
DEBUG(dbgs() << "Diverting " << oldedge << " via " << newedge );
// First check if the old edge was taken, if not, just delete it...
if (getEdgeWeight(oldedge) == 0) {
removeEdge(oldedge);
return;
}
Path P;
P[newedge.first] = 0;
P[newedge.second] = newedge.first;
const BasicBlock *BB = GetPath(newedge.second,oldedge.second,P,GetPathToExit | GetPathToDest);
double w = getEdgeWeight (oldedge);
DEBUG(dbgs() << ", Weight: " << format("%.20g",w) << "\n");
do {
const BasicBlock *Parent = P.find(BB)->second;
Edge e = getEdge(Parent,BB);
double oldw = getEdgeWeight(e);
double oldc = getExecutionCount(e.first);
setEdgeWeight(e, w+oldw);
if (Parent != oldedge.first) {
setExecutionCount(e.first, w+oldc);
}
BB = Parent;
} while (BB != newedge.first);
removeEdge(oldedge);
}
/// Replaces all occurrences of RmBB in the ProfilingInfo with DestBB.
/// This checks all edges of the function the blocks reside in and replaces the
/// occurrences of RmBB with DestBB.
template<>
void ProfileInfoT<Function,BasicBlock>::
replaceAllUses(const BasicBlock *RmBB, const BasicBlock *DestBB) {
DEBUG(dbgs() << "Replacing " << RmBB->getName()
<< " with " << DestBB->getName() << "\n");
const Function *F = DestBB->getParent();
std::map<const Function*, EdgeWeights>::iterator J =
EdgeInformation.find(F);
if (J == EdgeInformation.end()) return;
Edge e, newedge;
bool erasededge = false;
EdgeWeights::iterator I = J->second.begin(), E = J->second.end();
while(I != E) {
e = (I++)->first;
bool foundedge = false; bool eraseedge = false;
if (e.first == RmBB) {
if (e.second == DestBB) {
eraseedge = true;
} else {
newedge = getEdge(DestBB, e.second);
foundedge = true;
}
}
if (e.second == RmBB) {
if (e.first == DestBB) {
eraseedge = true;
} else {
newedge = getEdge(e.first, DestBB);
foundedge = true;
}
}
if (foundedge) {
replaceEdge(e, newedge);
}
if (eraseedge) {
if (erasededge) {
Edge newedge = getEdge(DestBB, DestBB);
replaceEdge(e, newedge);
} else {
removeEdge(e);
erasededge = true;
}
}
}
}
/// Splits an edge in the ProfileInfo and redirects flow over NewBB.
/// Since its possible that there is more than one edge in the CFG from FristBB
/// to SecondBB its necessary to redirect the flow proporionally.
template<>
void ProfileInfoT<Function,BasicBlock>::splitEdge(const BasicBlock *FirstBB,
const BasicBlock *SecondBB,
const BasicBlock *NewBB,
bool MergeIdenticalEdges) {
const Function *F = FirstBB->getParent();
std::map<const Function*, EdgeWeights>::iterator J =
EdgeInformation.find(F);
if (J == EdgeInformation.end()) return;
// Generate edges and read current weight.
Edge e = getEdge(FirstBB, SecondBB);
Edge n1 = getEdge(FirstBB, NewBB);
Edge n2 = getEdge(NewBB, SecondBB);
EdgeWeights &ECs = J->second;
double w = ECs[e];
int succ_count = 0;
if (!MergeIdenticalEdges) {
// First count the edges from FristBB to SecondBB, if there is more than
// one, only slice out a proporional part for NewBB.
for(succ_const_iterator BBI = succ_begin(FirstBB), BBE = succ_end(FirstBB);
BBI != BBE; ++BBI) {
if (*BBI == SecondBB) succ_count++;
}
// When the NewBB is completely new, increment the count by one so that
// the counts are properly distributed.
if (getExecutionCount(NewBB) == ProfileInfo::MissingValue) succ_count++;
} else {
// When the edges are merged anyway, then redirect all flow.
succ_count = 1;
}
// We know now how many edges there are from FirstBB to SecondBB, reroute a
// proportional part of the edge weight over NewBB.
double neww = floor(w / succ_count);
ECs[n1] += neww;
ECs[n2] += neww;
BlockInformation[F][NewBB] += neww;
if (succ_count == 1) {
ECs.erase(e);
} else {
ECs[e] -= neww;
}
}
template<>
void ProfileInfoT<Function,BasicBlock>::splitBlock(const BasicBlock *Old,
const BasicBlock* New) {
const Function *F = Old->getParent();
std::map<const Function*, EdgeWeights>::iterator J =
EdgeInformation.find(F);
if (J == EdgeInformation.end()) return;
DEBUG(dbgs() << "Splitting " << Old->getName() << " to " << New->getName() << "\n");
std::set<Edge> Edges;
for (EdgeWeights::iterator ewi = J->second.begin(), ewe = J->second.end();
ewi != ewe; ++ewi) {
Edge old = ewi->first;
if (old.first == Old) {
Edges.insert(old);
}
}
for (std::set<Edge>::iterator EI = Edges.begin(), EE = Edges.end();
EI != EE; ++EI) {
Edge newedge = getEdge(New, EI->second);
replaceEdge(*EI, newedge);
}
double w = getExecutionCount(Old);
setEdgeWeight(getEdge(Old, New), w);
setExecutionCount(New, w);
}
template<>
void ProfileInfoT<Function,BasicBlock>::splitBlock(const BasicBlock *BB,
const BasicBlock* NewBB,
BasicBlock *const *Preds,
unsigned NumPreds) {
const Function *F = BB->getParent();
std::map<const Function*, EdgeWeights>::iterator J =
EdgeInformation.find(F);
if (J == EdgeInformation.end()) return;
DEBUG(dbgs() << "Splitting " << NumPreds << " Edges from " << BB->getName()
<< " to " << NewBB->getName() << "\n");
// Collect weight that was redirected over NewBB.
double newweight = 0;
std::set<const BasicBlock *> ProcessedPreds;
// For all requestes Predecessors.
for (unsigned pred = 0; pred < NumPreds; ++pred) {
const BasicBlock * Pred = Preds[pred];
if (ProcessedPreds.insert(Pred).second) {
// Create edges and read old weight.
Edge oldedge = getEdge(Pred, BB);
Edge newedge = getEdge(Pred, NewBB);
// Remember how much weight was redirected.
newweight += getEdgeWeight(oldedge);
replaceEdge(oldedge,newedge);
}
}
Edge newedge = getEdge(NewBB,BB);
setEdgeWeight(newedge, newweight);
setExecutionCount(NewBB, newweight);
}
template<>
void ProfileInfoT<Function,BasicBlock>::transfer(const Function *Old,
const Function *New) {
DEBUG(dbgs() << "Replacing Function " << Old->getName() << " with "
<< New->getName() << "\n");
std::map<const Function*, EdgeWeights>::iterator J =
EdgeInformation.find(Old);
if(J != EdgeInformation.end()) {
EdgeInformation[New] = J->second;
}
EdgeInformation.erase(Old);
BlockInformation.erase(Old);
FunctionInformation.erase(Old);
}
static double readEdgeOrRemember(ProfileInfo::Edge edge, double w,
ProfileInfo::Edge &tocalc, unsigned &uncalc) {
if (w == ProfileInfo::MissingValue) {
tocalc = edge;
uncalc++;
return 0;
} else {
return w;
}
}
template<>
bool ProfileInfoT<Function,BasicBlock>::
CalculateMissingEdge(const BasicBlock *BB, Edge &removed,
bool assumeEmptySelf) {
Edge edgetocalc;
unsigned uncalculated = 0;
// collect weights of all incoming and outgoing edges, rememer edges that
// have no value
double incount = 0;
SmallSet<const BasicBlock*,8> pred_visited;
const_pred_iterator bbi = pred_begin(BB), bbe = pred_end(BB);
if (bbi==bbe) {
Edge e = getEdge(0,BB);
incount += readEdgeOrRemember(e, getEdgeWeight(e) ,edgetocalc,uncalculated);
}
for (;bbi != bbe; ++bbi) {
if (pred_visited.insert(*bbi)) {
Edge e = getEdge(*bbi,BB);
incount += readEdgeOrRemember(e, getEdgeWeight(e) ,edgetocalc,uncalculated);
}
}
double outcount = 0;
SmallSet<const BasicBlock*,8> succ_visited;
succ_const_iterator sbbi = succ_begin(BB), sbbe = succ_end(BB);
if (sbbi==sbbe) {
Edge e = getEdge(BB,0);
if (getEdgeWeight(e) == MissingValue) {
double w = getExecutionCount(BB);
if (w != MissingValue) {
setEdgeWeight(e,w);
removed = e;
}
}
outcount += readEdgeOrRemember(e, getEdgeWeight(e), edgetocalc, uncalculated);
}
for (;sbbi != sbbe; ++sbbi) {
if (succ_visited.insert(*sbbi)) {
Edge e = getEdge(BB,*sbbi);
outcount += readEdgeOrRemember(e, getEdgeWeight(e), edgetocalc, uncalculated);
}
}
// if exactly one edge weight was missing, calculate it and remove it from
// spanning tree
if (uncalculated == 0 ) {
return true;
} else
if (uncalculated == 1) {
if (incount < outcount) {
EdgeInformation[BB->getParent()][edgetocalc] = outcount-incount;
} else {
EdgeInformation[BB->getParent()][edgetocalc] = incount-outcount;
}
DEBUG(dbgs() << "--Calc Edge Counter for " << edgetocalc << ": "
<< format("%.20g", getEdgeWeight(edgetocalc)) << "\n");
removed = edgetocalc;
return true;
} else
if (uncalculated == 2 && assumeEmptySelf && edgetocalc.first == edgetocalc.second && incount == outcount) {
setEdgeWeight(edgetocalc, incount * 10);
removed = edgetocalc;
return true;
} else {
return false;
}
}
static void readEdge(ProfileInfo *PI, ProfileInfo::Edge e, double &calcw, std::set<ProfileInfo::Edge> &misscount) {
double w = PI->getEdgeWeight(e);
if (w != ProfileInfo::MissingValue) {
calcw += w;
} else {
misscount.insert(e);
}
}
template<>
bool ProfileInfoT<Function,BasicBlock>::EstimateMissingEdges(const BasicBlock *BB) {
double inWeight = 0;
std::set<Edge> inMissing;
std::set<const BasicBlock*> ProcessedPreds;
const_pred_iterator bbi = pred_begin(BB), bbe = pred_end(BB);
if (bbi == bbe) {
readEdge(this,getEdge(0,BB),inWeight,inMissing);
}
for( ; bbi != bbe; ++bbi ) {
if (ProcessedPreds.insert(*bbi).second) {
readEdge(this,getEdge(*bbi,BB),inWeight,inMissing);
}
}
double outWeight = 0;
std::set<Edge> outMissing;
std::set<const BasicBlock*> ProcessedSuccs;
succ_const_iterator sbbi = succ_begin(BB), sbbe = succ_end(BB);
if (sbbi == sbbe)
readEdge(this,getEdge(BB,0),outWeight,outMissing);
for ( ; sbbi != sbbe; ++sbbi ) {
if (ProcessedSuccs.insert(*sbbi).second) {
readEdge(this,getEdge(BB,*sbbi),outWeight,outMissing);
}
}
double share;
std::set<Edge>::iterator ei,ee;
if (inMissing.size() == 0 && outMissing.size() > 0) {
ei = outMissing.begin();
ee = outMissing.end();
share = inWeight/outMissing.size();
setExecutionCount(BB,inWeight);
} else
if (inMissing.size() > 0 && outMissing.size() == 0 && outWeight == 0) {
ei = inMissing.begin();
ee = inMissing.end();
share = 0;
setExecutionCount(BB,0);
} else
if (inMissing.size() == 0 && outMissing.size() == 0) {
setExecutionCount(BB,outWeight);
return true;
} else {
return false;
}
for ( ; ei != ee; ++ei ) {
setEdgeWeight(*ei,share);
}
return true;
}
template<>
void ProfileInfoT<Function,BasicBlock>::repair(const Function *F) {
// if (getExecutionCount(&(F->getEntryBlock())) == 0) {
// for (Function::const_iterator FI = F->begin(), FE = F->end();
// FI != FE; ++FI) {
// const BasicBlock* BB = &(*FI);
// {
// const_pred_iterator NBB = pred_begin(BB), End = pred_end(BB);
// if (NBB == End) {
// setEdgeWeight(getEdge(0,BB),0);
// }
// for(;NBB != End; ++NBB) {
// setEdgeWeight(getEdge(*NBB,BB),0);
// }
// }
// {
// succ_const_iterator NBB = succ_begin(BB), End = succ_end(BB);
// if (NBB == End) {
// setEdgeWeight(getEdge(0,BB),0);
// }
// for(;NBB != End; ++NBB) {
// setEdgeWeight(getEdge(*NBB,BB),0);
// }
// }
// }
// return;
// }
// The set of BasicBlocks that are still unvisited.
std::set<const BasicBlock*> Unvisited;
// The set of return edges (Edges with no successors).
std::set<Edge> ReturnEdges;
double ReturnWeight = 0;
// First iterate over the whole function and collect:
// 1) The blocks in this function in the Unvisited set.
// 2) The return edges in the ReturnEdges set.
// 3) The flow that is leaving the function already via return edges.
// Data structure for searching the function.
std::queue<const BasicBlock *> BFS;
const BasicBlock *BB = &(F->getEntryBlock());
BFS.push(BB);
Unvisited.insert(BB);
while (BFS.size()) {
BB = BFS.front(); BFS.pop();
succ_const_iterator NBB = succ_begin(BB), End = succ_end(BB);
if (NBB == End) {
Edge e = getEdge(BB,0);
double w = getEdgeWeight(e);
if (w == MissingValue) {
// If the return edge has no value, try to read value from block.
double bw = getExecutionCount(BB);
if (bw != MissingValue) {
setEdgeWeight(e,bw);
ReturnWeight += bw;
} else {
// If both return edge and block provide no value, collect edge.
ReturnEdges.insert(e);
}
} else {
// If the return edge has a proper value, collect it.
ReturnWeight += w;
}
}
for (;NBB != End; ++NBB) {
if (Unvisited.insert(*NBB).second) {
BFS.push(*NBB);
}
}
}
while (Unvisited.size() > 0) {
unsigned oldUnvisitedCount = Unvisited.size();
bool FoundPath = false;
// If there is only one edge left, calculate it.
if (ReturnEdges.size() == 1) {
ReturnWeight = getExecutionCount(&(F->getEntryBlock())) - ReturnWeight;
Edge e = *ReturnEdges.begin();
setEdgeWeight(e,ReturnWeight);
setExecutionCount(e.first,ReturnWeight);
Unvisited.erase(e.first);
ReturnEdges.erase(e);
continue;
}
// Calculate all blocks where only one edge is missing, this may also
// resolve furhter return edges.
std::set<const BasicBlock *>::iterator FI = Unvisited.begin(), FE = Unvisited.end();
while(FI != FE) {
const BasicBlock *BB = *FI; ++FI;
Edge e;
if(CalculateMissingEdge(BB,e,true)) {
if (BlockInformation[F].find(BB) == BlockInformation[F].end()) {
setExecutionCount(BB,getExecutionCount(BB));
}
Unvisited.erase(BB);
if (e.first != 0 && e.second == 0) {
ReturnEdges.erase(e);
ReturnWeight += getEdgeWeight(e);
}
}
}
if (oldUnvisitedCount > Unvisited.size()) continue;
// Estimate edge weights by dividing the flow proportionally.
FI = Unvisited.begin(), FE = Unvisited.end();
while(FI != FE) {
const BasicBlock *BB = *FI; ++FI;
const BasicBlock *Dest = 0;
bool AllEdgesHaveSameReturn = true;
// Check each Successor, these must all end up in the same or an empty
// return block otherwise its dangerous to do an estimation on them.
for (succ_const_iterator Succ = succ_begin(BB), End = succ_end(BB);
Succ != End; ++Succ) {
Path P;
GetPath(*Succ, 0, P, GetPathToExit);
if (Dest && Dest != P[0]) {
AllEdgesHaveSameReturn = false;
}
Dest = P[0];
}
if (AllEdgesHaveSameReturn) {
if(EstimateMissingEdges(BB)) {
Unvisited.erase(BB);
break;
}
}
}
if (oldUnvisitedCount > Unvisited.size()) continue;
// Check if there is a path to an block that has a known value and redirect
// flow accordingly.
FI = Unvisited.begin(), FE = Unvisited.end();
while(FI != FE && !FoundPath) {
// Fetch path.
const BasicBlock *BB = *FI; ++FI;
Path P;
const BasicBlock *Dest = GetPath(BB, 0, P, GetPathToValue);
// Calculate incoming flow.
double iw = 0; unsigned inmissing = 0; unsigned incount = 0; unsigned invalid = 0;
std::set<const BasicBlock *> Processed;
for (const_pred_iterator NBB = pred_begin(BB), End = pred_end(BB);
NBB != End; ++NBB) {
if (Processed.insert(*NBB).second) {
Edge e = getEdge(*NBB, BB);
double ew = getEdgeWeight(e);
if (ew != MissingValue) {
iw += ew;
invalid++;
} else {
// If the path contains the successor, this means its a backedge,
// do not count as missing.
if (P.find(*NBB) == P.end())
inmissing++;
}
incount++;
}
}
if (inmissing == incount) continue;
if (invalid == 0) continue;
// Subtract (already) outgoing flow.
Processed.clear();
for (succ_const_iterator NBB = succ_begin(BB), End = succ_end(BB);
NBB != End; ++NBB) {
if (Processed.insert(*NBB).second) {
Edge e = getEdge(BB, *NBB);
double ew = getEdgeWeight(e);
if (ew != MissingValue) {
iw -= ew;
}
}
}
if (iw < 0) continue;
// Check the receiving end of the path if it can handle the flow.
double ow = getExecutionCount(Dest);
Processed.clear();
for (succ_const_iterator NBB = succ_begin(BB), End = succ_end(BB);
NBB != End; ++NBB) {
if (Processed.insert(*NBB).second) {
Edge e = getEdge(BB, *NBB);
double ew = getEdgeWeight(e);
if (ew != MissingValue) {
ow -= ew;
}
}
}
if (ow < 0) continue;
// Determine how much flow shall be used.
double ew = getEdgeWeight(getEdge(P[Dest],Dest));
if (ew != MissingValue) {
ew = ew<ow?ew:ow;
ew = ew<iw?ew:iw;
} else {
if (inmissing == 0)
ew = iw;
}
// Create flow.
if (ew != MissingValue) {
do {
Edge e = getEdge(P[Dest],Dest);
if (getEdgeWeight(e) == MissingValue) {
setEdgeWeight(e,ew);
FoundPath = true;
}
Dest = P[Dest];
} while (Dest != BB);
}
}
if (FoundPath) continue;
// Calculate a block with self loop.
FI = Unvisited.begin(), FE = Unvisited.end();
while(FI != FE && !FoundPath) {
const BasicBlock *BB = *FI; ++FI;
bool SelfEdgeFound = false;
for (succ_const_iterator NBB = succ_begin(BB), End = succ_end(BB);
NBB != End; ++NBB) {
if (*NBB == BB) {
SelfEdgeFound = true;
break;
}
}
if (SelfEdgeFound) {
Edge e = getEdge(BB,BB);
if (getEdgeWeight(e) == MissingValue) {
double iw = 0;
std::set<const BasicBlock *> Processed;
for (const_pred_iterator NBB = pred_begin(BB), End = pred_end(BB);
NBB != End; ++NBB) {
if (Processed.insert(*NBB).second) {
Edge e = getEdge(*NBB, BB);
double ew = getEdgeWeight(e);
if (ew != MissingValue) {
iw += ew;
}
}
}
setEdgeWeight(e,iw * 10);
FoundPath = true;
}
}
}
if (FoundPath) continue;
// Determine backedges, set them to zero.
FI = Unvisited.begin(), FE = Unvisited.end();
while(FI != FE && !FoundPath) {
const BasicBlock *BB = *FI; ++FI;
const BasicBlock *Dest = 0;
Path P;
bool BackEdgeFound = false;
for (const_pred_iterator NBB = pred_begin(BB), End = pred_end(BB);
NBB != End; ++NBB) {
Dest = GetPath(BB, *NBB, P, GetPathToDest | GetPathWithNewEdges);
if (Dest == *NBB) {
BackEdgeFound = true;
break;
}
}
if (BackEdgeFound) {
Edge e = getEdge(Dest,BB);
double w = getEdgeWeight(e);
if (w == MissingValue) {
setEdgeWeight(e,0);
FoundPath = true;
}
do {
Edge e = getEdge(P[Dest], Dest);
double w = getEdgeWeight(e);
if (w == MissingValue) {
setEdgeWeight(e,0);
FoundPath = true;
}
Dest = P[Dest];
} while (Dest != BB);
}
}
if (FoundPath) continue;
// Channel flow to return block.
FI = Unvisited.begin(), FE = Unvisited.end();
while(FI != FE && !FoundPath) {
const BasicBlock *BB = *FI; ++FI;
Path P;
const BasicBlock *Dest = GetPath(BB, 0, P, GetPathToExit | GetPathWithNewEdges);
Dest = P[0];
if (!Dest) continue;
if (getEdgeWeight(getEdge(Dest,0)) == MissingValue) {
// Calculate incoming flow.
double iw = 0;
std::set<const BasicBlock *> Processed;
for (const_pred_iterator NBB = pred_begin(BB), End = pred_end(BB);
NBB != End; ++NBB) {
if (Processed.insert(*NBB).second) {
Edge e = getEdge(*NBB, BB);
double ew = getEdgeWeight(e);
if (ew != MissingValue) {
iw += ew;
}
}
}
do {
Edge e = getEdge(P[Dest], Dest);
double w = getEdgeWeight(e);
if (w == MissingValue) {
setEdgeWeight(e,iw);
FoundPath = true;
} else {
assert(0 && "Edge should not have value already!");
}
Dest = P[Dest];
} while (Dest != BB);
}
}
if (FoundPath) continue;
// Speculatively set edges to zero.
FI = Unvisited.begin(), FE = Unvisited.end();
while(FI != FE && !FoundPath) {
const BasicBlock *BB = *FI; ++FI;
for (const_pred_iterator NBB = pred_begin(BB), End = pred_end(BB);
NBB != End; ++NBB) {
Edge e = getEdge(*NBB,BB);
double w = getEdgeWeight(e);
if (w == MissingValue) {
setEdgeWeight(e,0);
FoundPath = true;
break;
}
}
}
if (FoundPath) continue;
errs() << "{";
FI = Unvisited.begin(), FE = Unvisited.end();
while(FI != FE) {
const BasicBlock *BB = *FI; ++FI;
dbgs() << BB->getName();
if (FI != FE)
dbgs() << ",";
}
errs() << "}";
errs() << "ASSERT: could not repair function";
assert(0 && "could not repair function");
}
EdgeWeights J = EdgeInformation[F];
for (EdgeWeights::iterator EI = J.begin(), EE = J.end(); EI != EE; ++EI) {
Edge e = EI->first;
bool SuccFound = false;
if (e.first != 0) {
succ_const_iterator NBB = succ_begin(e.first), End = succ_end(e.first);
if (NBB == End) {
if (0 == e.second) {
SuccFound = true;
}
}
for (;NBB != End; ++NBB) {
if (*NBB == e.second) {
SuccFound = true;
break;
}
}
if (!SuccFound) {
removeEdge(e);
}
}
}
}
raw_ostream& operator<<(raw_ostream &O, const MachineFunction *MF) {
return O << MF->getFunction()->getName() << "(MF)";
}
raw_ostream& operator<<(raw_ostream &O, const MachineBasicBlock *MBB) {
return O << MBB->getBasicBlock()->getName() << "(MB)";
}
raw_ostream& operator<<(raw_ostream &O, std::pair<const MachineBasicBlock *, const MachineBasicBlock *> E) {
O << "(";
if (E.first)
O << E.first;
else
O << "0";
O << ",";
if (E.second)
O << E.second;
else
O << "0";
return O << ")";
}
} // namespace llvm
//===----------------------------------------------------------------------===//
// NoProfile ProfileInfo implementation
//
namespace {
struct NoProfileInfo : public ImmutablePass, public ProfileInfo {
static char ID; // Class identification, replacement for typeinfo
NoProfileInfo() : ImmutablePass(ID) {
initializeNoProfileInfoPass(*PassRegistry::getPassRegistry());
}
/// getAdjustedAnalysisPointer - This method is used when a pass implements
/// an analysis interface through multiple inheritance. If needed, it
/// should override this to adjust the this pointer as needed for the
/// specified pass info.
virtual void *getAdjustedAnalysisPointer(AnalysisID PI) {
if (PI == &ProfileInfo::ID)
return (ProfileInfo*)this;
return this;
}
virtual const char *getPassName() const {
return "NoProfileInfo";
}
};
} // End of anonymous namespace
char NoProfileInfo::ID = 0;
// Register this pass...
INITIALIZE_AG_PASS(NoProfileInfo, ProfileInfo, "no-profile",
"No Profile Information", false, true, true)
ImmutablePass *llvm::createNoProfileInfoPass() { return new NoProfileInfo(); }
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