* Remove function to find "main" in a Module, there's a method for that

* Removing extraneous empty space and empty comment lines


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12014 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Misha Brukman 2004-02-29 23:09:10 +00:00
parent cbee990a29
commit 99cc88bb64
2 changed files with 242 additions and 330 deletions

View File

@ -91,10 +91,7 @@ static bool isSync(const CallInst& CI) {
// Code generation pass that transforms code to identify where Cilk keywords
// should be inserted. This relies on `llvm-dis -c' to print out the keywords.
//----------------------------------------------------------------------------
class Cilkifier: public InstVisitor<Cilkifier>
{
class Cilkifier: public InstVisitor<Cilkifier> {
Function* DummySyncFunc;
// Data used when transforming each function.
@ -124,16 +121,14 @@ public:
};
Cilkifier::Cilkifier(Module& M)
{
Cilkifier::Cilkifier(Module& M) {
// create the dummy Sync function and add it to the Module
DummySyncFunc = M.getOrInsertFunction(DummySyncFuncName, Type::VoidTy, 0);
}
void Cilkifier::TransformFunc(Function* F,
const hash_set<Function*>& _cilkFunctions,
PgmDependenceGraph& _depGraph)
{
PgmDependenceGraph& _depGraph) {
// Memoize the information for this function
cilkFunctions = &_cilkFunctions;
depGraph = &_depGraph;
@ -159,20 +154,19 @@ void Cilkifier::DFSVisitInstr(Instruction* I,
stmtsVisited.insert(I);
// If there is a dependence from root to I, insert Sync and return
if (depsOfRoot.find(I) != depsOfRoot.end())
{ // Insert a sync before I and stop searching along this path.
if (depsOfRoot.find(I) != depsOfRoot.end()) {
// Insert a sync before I and stop searching along this path.
// If I is a Phi instruction, the dependence can only be an SSA dep.
// and we need to insert the sync in the predecessor on the appropriate
// incoming edge!
CallInst* syncI = 0;
if (PHINode* phiI = dyn_cast<PHINode>(I))
{ // check all operands of the Phi and insert before each one
if (PHINode* phiI = dyn_cast<PHINode>(I)) {
// check all operands of the Phi and insert before each one
for (unsigned i = 0, N = phiI->getNumIncomingValues(); i < N; ++i)
if (phiI->getIncomingValue(i) == root)
syncI = new CallInst(DummySyncFunc, std::vector<Value*>(), "",
phiI->getIncomingBlock(i)->getTerminator());
}
else
} else
syncI = new CallInst(DummySyncFunc, std::vector<Value*>(), "", I);
// Remember the sync for each spawn to eliminate redundant ones later
@ -182,14 +176,13 @@ void Cilkifier::DFSVisitInstr(Instruction* I,
}
// else visit unvisited successors
if (BranchInst* brI = dyn_cast<BranchInst>(I))
{ // visit first instruction in each successor BB
if (BranchInst* brI = dyn_cast<BranchInst>(I)) {
// visit first instruction in each successor BB
for (unsigned i = 0, N = brI->getNumSuccessors(); i < N; ++i)
if (stmtsVisited.find(&brI->getSuccessor(i)->front())
== stmtsVisited.end())
DFSVisitInstr(&brI->getSuccessor(i)->front(), root, depsOfRoot);
}
else
} else
if (Instruction* nextI = I->getNext())
if (stmtsVisited.find(nextI) == stmtsVisited.end())
DFSVisitInstr(nextI, root, depsOfRoot);
@ -214,10 +207,8 @@ void Cilkifier::visitCallInst(CallInst& CI)
std::vector<const PHINode*> phiUsers;
hash_set<const PHINode*> phisSeen; // ensures we don't visit a phi twice
for (Value::use_iterator UI=CI.use_begin(), UE=CI.use_end(); UI != UE; ++UI)
if (const PHINode* phiUser = dyn_cast<PHINode>(*UI))
{
if (phisSeen.find(phiUser) == phisSeen.end())
{
if (const PHINode* phiUser = dyn_cast<PHINode>(*UI)) {
if (phisSeen.find(phiUser) == phisSeen.end()) {
phiUsers.push_back(phiUser);
phisSeen.insert(phiUser);
}
@ -227,27 +218,22 @@ void Cilkifier::visitCallInst(CallInst& CI)
// Now we've found the non-Phi users and immediate phi users.
// Recursively walk the phi users and add their non-phi users.
for (const PHINode* phiUser; !phiUsers.empty(); phiUsers.pop_back())
{
for (const PHINode* phiUser; !phiUsers.empty(); phiUsers.pop_back()) {
phiUser = phiUsers.back();
for (Value::use_const_iterator UI=phiUser->use_begin(),
UE=phiUser->use_end(); UI != UE; ++UI)
if (const PHINode* pn = dyn_cast<PHINode>(*UI))
{
if (phisSeen.find(pn) == phisSeen.end())
{
if (const PHINode* pn = dyn_cast<PHINode>(*UI)) {
if (phisSeen.find(pn) == phisSeen.end()) {
phiUsers.push_back(pn);
phisSeen.insert(pn);
}
}
else
} else
depsOfRoot.insert(cast<Instruction>(*UI));
}
// Walk paths of the CFG starting at the call instruction and insert
// one sync before the first dependence on each path, if any.
if (! depsOfRoot.empty())
{
if (! depsOfRoot.empty()) {
stmtsVisited.clear(); // start a new DFS for this CallInst
assert(CI.getNext() && "Call instruction cannot be a terminator!");
DFSVisitInstr(CI.getNext(), &CI, depsOfRoot);
@ -304,25 +290,22 @@ FindParallelCalls::FindParallelCalls(Function& F,
// Now we've found all CallInsts reachable from each CallInst.
// Find those CallInsts that are parallel with at least one other CallInst
// by counting total inEdges and outEdges.
//
unsigned long totalNumCalls = completed.size();
if (totalNumCalls == 1)
{ // Check first for the special case of a single call instruction not
if (totalNumCalls == 1) {
// Check first for the special case of a single call instruction not
// in any loop. It is not parallel, even if it has no dependences
// (this is why it is a special case).
//
// FIXME:
// THIS CASE IS NOT HANDLED RIGHT NOW, I.E., THERE IS NO
// PARALLELISM FOR CALLS IN DIFFERENT ITERATIONS OF A LOOP.
//
return;
}
hash_map<CallInst*, unsigned long> numDeps;
for (hash_map<CallInst*, DependentsSet>::iterator II = dependents.begin(),
IE = dependents.end(); II != IE; ++II)
{
IE = dependents.end(); II != IE; ++II) {
CallInst* fromCI = II->first;
numDeps[fromCI] += II->second.size();
for (Dependents_iterator DI = II->second.begin(), DE = II->second.end();
@ -347,17 +330,14 @@ void FindParallelCalls::VisitOutEdges(Instruction* I,
stmtsVisited.insert(I);
if (CallInst* CI = dyn_cast<CallInst>(I))
// FIXME: Ignoring parallelism in a loop. Here we're actually *ignoring*
// a self-dependence in order to get the count comparison right above.
// When we include loop parallelism, self-dependences should be included.
//
if (CI != root)
{ // CallInst root has a path to CallInst I and any calls reachable from I
if (CI != root) {
// CallInst root has a path to CallInst I and any calls reachable from I
depsOfRoot.insert(CI);
if (completed[CI])
{ // We have already visited I so we know all nodes it can reach!
if (completed[CI]) {
// We have already visited I so we know all nodes it can reach!
DependentsSet& depsOfI = dependents[CI];
depsOfRoot.insert(depsOfI.begin(), depsOfI.end());
return;
@ -366,8 +346,7 @@ void FindParallelCalls::VisitOutEdges(Instruction* I,
// If we reach here, we need to visit all children of I
for (PgmDependenceGraph::iterator DI = depGraph.outDepBegin(*I);
! DI.fini(); ++DI)
{
! DI.fini(); ++DI) {
Instruction* sink = &DI->getSink()->getInstr();
if (stmtsVisited.find(sink) == stmtsVisited.end())
VisitOutEdges(sink, root, depsOfRoot);
@ -375,8 +354,7 @@ void FindParallelCalls::VisitOutEdges(Instruction* I,
}
void FindParallelCalls::visitCallInst(CallInst& CI)
{
void FindParallelCalls::visitCallInst(CallInst& CI) {
if (completed[&CI])
return;
stmtsVisited.clear(); // clear flags to do a fresh DFS
@ -384,8 +362,7 @@ void FindParallelCalls::visitCallInst(CallInst& CI)
// Visit all children of CI using a recursive walk through dep graph
DependentsSet& depsOfRoot = dependents[&CI];
for (PgmDependenceGraph::iterator DI = depGraph.outDepBegin(CI);
! DI.fini(); ++DI)
{
! DI.fini(); ++DI) {
Instruction* sink = &DI->getSink()->getInstr();
if (stmtsVisited.find(sink) == stmtsVisited.end())
VisitOutEdges(sink, &CI, depsOfRoot);
@ -411,8 +388,7 @@ void FindParallelCalls::visitCallInst(CallInst& CI)
//----------------------------------------------------------------------------
namespace {
class Parallelize: public Pass
{
class Parallelize: public Pass {
public:
/// Driver functions to transform a program
///
@ -433,58 +409,41 @@ namespace {
}
static Function* FindMain(Module& M)
{
for (Module::iterator FI = M.begin(), FE = M.end(); FI != FE; ++FI)
if (FI->getName() == std::string("main"))
return FI;
return NULL;
}
bool Parallelize::run(Module& M)
{
bool Parallelize::run(Module& M) {
hash_set<Function*> parallelFunctions;
hash_set<Function*> safeParallelFunctions;
hash_set<const GlobalValue*> indirectlyCalled;
// If there is no main (i.e., for an incomplete program), we can do nothing.
// If there is a main, mark main as a parallel function.
//
Function* mainFunc = FindMain(M);
Function* mainFunc = M.getMainFunction();
if (!mainFunc)
return false;
// (1) Find candidate parallel functions and mark them as Cilk functions
//
for (Module::iterator FI = M.begin(), FE = M.end(); FI != FE; ++FI)
if (! FI->isExternal())
{
if (! FI->isExternal()) {
Function* F = FI;
DSGraph& tdg = getAnalysis<TDDataStructures>().getDSGraph(*F);
// All the hard analysis work gets done here!
//
FindParallelCalls finder(*F,
getAnalysis<PgmDependenceGraph>().getGraph(*F));
/* getAnalysis<MemoryDepAnalysis>().getGraph(*F)); */
// Now we know which call instructions are useful to parallelize.
// Remember those callee functions.
//
for (std::vector<CallInst*>::iterator
CII = finder.parallelCalls.begin(),
CIE = finder.parallelCalls.end(); CII != CIE; ++CII)
{
CIE = finder.parallelCalls.end(); CII != CIE; ++CII) {
// Check if this is a direct call...
if ((*CII)->getCalledFunction() != NULL)
{ // direct call: if this is to a non-external function,
if ((*CII)->getCalledFunction() != NULL) {
// direct call: if this is to a non-external function,
// mark it as a parallelizable function
if (! (*CII)->getCalledFunction()->isExternal())
parallelFunctions.insert((*CII)->getCalledFunction());
}
else
{ // Indirect call: mark all potential callees as bad
} else {
// Indirect call: mark all potential callees as bad
std::vector<GlobalValue*> callees =
tdg.getNodeForValue((*CII)->getCalledValue())
.getNode()->getGlobals();
@ -494,7 +453,6 @@ bool Parallelize::run(Module& M)
}
// Remove all indirectly called functions from the list of Cilk functions.
//
for (hash_set<Function*>::iterator PFI = parallelFunctions.begin(),
PFE = parallelFunctions.end(); PFI != PFE; ++PFI)
if (indirectlyCalled.count(*PFI) == 0)
@ -524,11 +482,9 @@ bool Parallelize::run(Module& M)
// This should identify both functions and calls to such functions
// to the code generator.
// (4) Also, insert calls to sync at appropriate points.
//
Cilkifier cilkifier(M);
for (hash_set<Function*>::iterator CFI = safeParallelFunctions.begin(),
CFE = safeParallelFunctions.end(); CFI != CFE; ++CFI)
{
CFE = safeParallelFunctions.end(); CFI != CFE; ++CFI) {
cilkifier.TransformFunc(*CFI, safeParallelFunctions,
getAnalysis<PgmDependenceGraph>().getGraph(**CFI));
/* getAnalysis<MemoryDepAnalysis>().getGraph(**CFI)); */

View File

@ -91,10 +91,7 @@ static bool isSync(const CallInst& CI) {
// Code generation pass that transforms code to identify where Cilk keywords
// should be inserted. This relies on `llvm-dis -c' to print out the keywords.
//----------------------------------------------------------------------------
class Cilkifier: public InstVisitor<Cilkifier>
{
class Cilkifier: public InstVisitor<Cilkifier> {
Function* DummySyncFunc;
// Data used when transforming each function.
@ -124,16 +121,14 @@ public:
};
Cilkifier::Cilkifier(Module& M)
{
Cilkifier::Cilkifier(Module& M) {
// create the dummy Sync function and add it to the Module
DummySyncFunc = M.getOrInsertFunction(DummySyncFuncName, Type::VoidTy, 0);
}
void Cilkifier::TransformFunc(Function* F,
const hash_set<Function*>& _cilkFunctions,
PgmDependenceGraph& _depGraph)
{
PgmDependenceGraph& _depGraph) {
// Memoize the information for this function
cilkFunctions = &_cilkFunctions;
depGraph = &_depGraph;
@ -159,20 +154,19 @@ void Cilkifier::DFSVisitInstr(Instruction* I,
stmtsVisited.insert(I);
// If there is a dependence from root to I, insert Sync and return
if (depsOfRoot.find(I) != depsOfRoot.end())
{ // Insert a sync before I and stop searching along this path.
if (depsOfRoot.find(I) != depsOfRoot.end()) {
// Insert a sync before I and stop searching along this path.
// If I is a Phi instruction, the dependence can only be an SSA dep.
// and we need to insert the sync in the predecessor on the appropriate
// incoming edge!
CallInst* syncI = 0;
if (PHINode* phiI = dyn_cast<PHINode>(I))
{ // check all operands of the Phi and insert before each one
if (PHINode* phiI = dyn_cast<PHINode>(I)) {
// check all operands of the Phi and insert before each one
for (unsigned i = 0, N = phiI->getNumIncomingValues(); i < N; ++i)
if (phiI->getIncomingValue(i) == root)
syncI = new CallInst(DummySyncFunc, std::vector<Value*>(), "",
phiI->getIncomingBlock(i)->getTerminator());
}
else
} else
syncI = new CallInst(DummySyncFunc, std::vector<Value*>(), "", I);
// Remember the sync for each spawn to eliminate redundant ones later
@ -182,14 +176,13 @@ void Cilkifier::DFSVisitInstr(Instruction* I,
}
// else visit unvisited successors
if (BranchInst* brI = dyn_cast<BranchInst>(I))
{ // visit first instruction in each successor BB
if (BranchInst* brI = dyn_cast<BranchInst>(I)) {
// visit first instruction in each successor BB
for (unsigned i = 0, N = brI->getNumSuccessors(); i < N; ++i)
if (stmtsVisited.find(&brI->getSuccessor(i)->front())
== stmtsVisited.end())
DFSVisitInstr(&brI->getSuccessor(i)->front(), root, depsOfRoot);
}
else
} else
if (Instruction* nextI = I->getNext())
if (stmtsVisited.find(nextI) == stmtsVisited.end())
DFSVisitInstr(nextI, root, depsOfRoot);
@ -214,10 +207,8 @@ void Cilkifier::visitCallInst(CallInst& CI)
std::vector<const PHINode*> phiUsers;
hash_set<const PHINode*> phisSeen; // ensures we don't visit a phi twice
for (Value::use_iterator UI=CI.use_begin(), UE=CI.use_end(); UI != UE; ++UI)
if (const PHINode* phiUser = dyn_cast<PHINode>(*UI))
{
if (phisSeen.find(phiUser) == phisSeen.end())
{
if (const PHINode* phiUser = dyn_cast<PHINode>(*UI)) {
if (phisSeen.find(phiUser) == phisSeen.end()) {
phiUsers.push_back(phiUser);
phisSeen.insert(phiUser);
}
@ -227,27 +218,22 @@ void Cilkifier::visitCallInst(CallInst& CI)
// Now we've found the non-Phi users and immediate phi users.
// Recursively walk the phi users and add their non-phi users.
for (const PHINode* phiUser; !phiUsers.empty(); phiUsers.pop_back())
{
for (const PHINode* phiUser; !phiUsers.empty(); phiUsers.pop_back()) {
phiUser = phiUsers.back();
for (Value::use_const_iterator UI=phiUser->use_begin(),
UE=phiUser->use_end(); UI != UE; ++UI)
if (const PHINode* pn = dyn_cast<PHINode>(*UI))
{
if (phisSeen.find(pn) == phisSeen.end())
{
if (const PHINode* pn = dyn_cast<PHINode>(*UI)) {
if (phisSeen.find(pn) == phisSeen.end()) {
phiUsers.push_back(pn);
phisSeen.insert(pn);
}
}
else
} else
depsOfRoot.insert(cast<Instruction>(*UI));
}
// Walk paths of the CFG starting at the call instruction and insert
// one sync before the first dependence on each path, if any.
if (! depsOfRoot.empty())
{
if (! depsOfRoot.empty()) {
stmtsVisited.clear(); // start a new DFS for this CallInst
assert(CI.getNext() && "Call instruction cannot be a terminator!");
DFSVisitInstr(CI.getNext(), &CI, depsOfRoot);
@ -304,25 +290,22 @@ FindParallelCalls::FindParallelCalls(Function& F,
// Now we've found all CallInsts reachable from each CallInst.
// Find those CallInsts that are parallel with at least one other CallInst
// by counting total inEdges and outEdges.
//
unsigned long totalNumCalls = completed.size();
if (totalNumCalls == 1)
{ // Check first for the special case of a single call instruction not
if (totalNumCalls == 1) {
// Check first for the special case of a single call instruction not
// in any loop. It is not parallel, even if it has no dependences
// (this is why it is a special case).
//
// FIXME:
// THIS CASE IS NOT HANDLED RIGHT NOW, I.E., THERE IS NO
// PARALLELISM FOR CALLS IN DIFFERENT ITERATIONS OF A LOOP.
//
return;
}
hash_map<CallInst*, unsigned long> numDeps;
for (hash_map<CallInst*, DependentsSet>::iterator II = dependents.begin(),
IE = dependents.end(); II != IE; ++II)
{
IE = dependents.end(); II != IE; ++II) {
CallInst* fromCI = II->first;
numDeps[fromCI] += II->second.size();
for (Dependents_iterator DI = II->second.begin(), DE = II->second.end();
@ -347,17 +330,14 @@ void FindParallelCalls::VisitOutEdges(Instruction* I,
stmtsVisited.insert(I);
if (CallInst* CI = dyn_cast<CallInst>(I))
// FIXME: Ignoring parallelism in a loop. Here we're actually *ignoring*
// a self-dependence in order to get the count comparison right above.
// When we include loop parallelism, self-dependences should be included.
//
if (CI != root)
{ // CallInst root has a path to CallInst I and any calls reachable from I
if (CI != root) {
// CallInst root has a path to CallInst I and any calls reachable from I
depsOfRoot.insert(CI);
if (completed[CI])
{ // We have already visited I so we know all nodes it can reach!
if (completed[CI]) {
// We have already visited I so we know all nodes it can reach!
DependentsSet& depsOfI = dependents[CI];
depsOfRoot.insert(depsOfI.begin(), depsOfI.end());
return;
@ -366,8 +346,7 @@ void FindParallelCalls::VisitOutEdges(Instruction* I,
// If we reach here, we need to visit all children of I
for (PgmDependenceGraph::iterator DI = depGraph.outDepBegin(*I);
! DI.fini(); ++DI)
{
! DI.fini(); ++DI) {
Instruction* sink = &DI->getSink()->getInstr();
if (stmtsVisited.find(sink) == stmtsVisited.end())
VisitOutEdges(sink, root, depsOfRoot);
@ -375,8 +354,7 @@ void FindParallelCalls::VisitOutEdges(Instruction* I,
}
void FindParallelCalls::visitCallInst(CallInst& CI)
{
void FindParallelCalls::visitCallInst(CallInst& CI) {
if (completed[&CI])
return;
stmtsVisited.clear(); // clear flags to do a fresh DFS
@ -384,8 +362,7 @@ void FindParallelCalls::visitCallInst(CallInst& CI)
// Visit all children of CI using a recursive walk through dep graph
DependentsSet& depsOfRoot = dependents[&CI];
for (PgmDependenceGraph::iterator DI = depGraph.outDepBegin(CI);
! DI.fini(); ++DI)
{
! DI.fini(); ++DI) {
Instruction* sink = &DI->getSink()->getInstr();
if (stmtsVisited.find(sink) == stmtsVisited.end())
VisitOutEdges(sink, &CI, depsOfRoot);
@ -411,8 +388,7 @@ void FindParallelCalls::visitCallInst(CallInst& CI)
//----------------------------------------------------------------------------
namespace {
class Parallelize: public Pass
{
class Parallelize: public Pass {
public:
/// Driver functions to transform a program
///
@ -433,58 +409,41 @@ namespace {
}
static Function* FindMain(Module& M)
{
for (Module::iterator FI = M.begin(), FE = M.end(); FI != FE; ++FI)
if (FI->getName() == std::string("main"))
return FI;
return NULL;
}
bool Parallelize::run(Module& M)
{
bool Parallelize::run(Module& M) {
hash_set<Function*> parallelFunctions;
hash_set<Function*> safeParallelFunctions;
hash_set<const GlobalValue*> indirectlyCalled;
// If there is no main (i.e., for an incomplete program), we can do nothing.
// If there is a main, mark main as a parallel function.
//
Function* mainFunc = FindMain(M);
Function* mainFunc = M.getMainFunction();
if (!mainFunc)
return false;
// (1) Find candidate parallel functions and mark them as Cilk functions
//
for (Module::iterator FI = M.begin(), FE = M.end(); FI != FE; ++FI)
if (! FI->isExternal())
{
if (! FI->isExternal()) {
Function* F = FI;
DSGraph& tdg = getAnalysis<TDDataStructures>().getDSGraph(*F);
// All the hard analysis work gets done here!
//
FindParallelCalls finder(*F,
getAnalysis<PgmDependenceGraph>().getGraph(*F));
/* getAnalysis<MemoryDepAnalysis>().getGraph(*F)); */
// Now we know which call instructions are useful to parallelize.
// Remember those callee functions.
//
for (std::vector<CallInst*>::iterator
CII = finder.parallelCalls.begin(),
CIE = finder.parallelCalls.end(); CII != CIE; ++CII)
{
CIE = finder.parallelCalls.end(); CII != CIE; ++CII) {
// Check if this is a direct call...
if ((*CII)->getCalledFunction() != NULL)
{ // direct call: if this is to a non-external function,
if ((*CII)->getCalledFunction() != NULL) {
// direct call: if this is to a non-external function,
// mark it as a parallelizable function
if (! (*CII)->getCalledFunction()->isExternal())
parallelFunctions.insert((*CII)->getCalledFunction());
}
else
{ // Indirect call: mark all potential callees as bad
} else {
// Indirect call: mark all potential callees as bad
std::vector<GlobalValue*> callees =
tdg.getNodeForValue((*CII)->getCalledValue())
.getNode()->getGlobals();
@ -494,7 +453,6 @@ bool Parallelize::run(Module& M)
}
// Remove all indirectly called functions from the list of Cilk functions.
//
for (hash_set<Function*>::iterator PFI = parallelFunctions.begin(),
PFE = parallelFunctions.end(); PFI != PFE; ++PFI)
if (indirectlyCalled.count(*PFI) == 0)
@ -524,11 +482,9 @@ bool Parallelize::run(Module& M)
// This should identify both functions and calls to such functions
// to the code generator.
// (4) Also, insert calls to sync at appropriate points.
//
Cilkifier cilkifier(M);
for (hash_set<Function*>::iterator CFI = safeParallelFunctions.begin(),
CFE = safeParallelFunctions.end(); CFI != CFE; ++CFI)
{
CFE = safeParallelFunctions.end(); CFI != CFE; ++CFI) {
cilkifier.TransformFunc(*CFI, safeParallelFunctions,
getAnalysis<PgmDependenceGraph>().getGraph(**CFI));
/* getAnalysis<MemoryDepAnalysis>().getGraph(**CFI)); */