llvm-6502/lib/IR/PassManager.cpp
Juergen Ributzka 9bc1b73c9e Add C API for thread yielding callback.
Sometimes a LLVM compilation may take more time then a client would like to
wait for. The problem is that it is not possible to safely suspend the LLVM
thread from the outside. When the timing is bad it might be possible that the
LLVM thread holds a global mutex and this would block any progress in any other
thread.

This commit adds a new yield callback function that can be registered with a
context. LLVM will try to yield by calling this callback function, but there is
no guaranteed frequency. LLVM will only do so if it can guarantee that
suspending the thread won't block any forward progress in other LLVM contexts
in the same process.

Once the client receives the call back it can suspend the thread safely and
resume it at another time.

Related to <rdar://problem/16728690>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208945 91177308-0d34-0410-b5e6-96231b3b80d8
2014-05-16 02:33:15 +00:00

205 lines
6.8 KiB
C++

//===- PassManager.cpp - Infrastructure for managing & running IR passes --===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "llvm/ADT/STLExtras.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/PassManager.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
using namespace llvm;
static cl::opt<bool>
DebugPM("debug-pass-manager", cl::Hidden,
cl::desc("Print pass management debugging information"));
PreservedAnalyses ModulePassManager::run(Module *M, ModuleAnalysisManager *AM) {
PreservedAnalyses PA = PreservedAnalyses::all();
if (DebugPM)
dbgs() << "Starting module pass manager run.\n";
for (unsigned Idx = 0, Size = Passes.size(); Idx != Size; ++Idx) {
if (DebugPM)
dbgs() << "Running module pass: " << Passes[Idx]->name() << "\n";
PreservedAnalyses PassPA = Passes[Idx]->run(M, AM);
if (AM)
AM->invalidate(M, PassPA);
PA.intersect(std::move(PassPA));
M->getContext().yield();
}
if (DebugPM)
dbgs() << "Finished module pass manager run.\n";
return PA;
}
ModuleAnalysisManager::ResultConceptT &
ModuleAnalysisManager::getResultImpl(void *PassID, Module *M) {
ModuleAnalysisResultMapT::iterator RI;
bool Inserted;
std::tie(RI, Inserted) = ModuleAnalysisResults.insert(std::make_pair(
PassID, std::unique_ptr<detail::AnalysisResultConcept<Module *>>()));
// If we don't have a cached result for this module, look up the pass and run
// it to produce a result, which we then add to the cache.
if (Inserted)
RI->second = std::move(lookupPass(PassID).run(M, this));
return *RI->second;
}
ModuleAnalysisManager::ResultConceptT *
ModuleAnalysisManager::getCachedResultImpl(void *PassID, Module *M) const {
ModuleAnalysisResultMapT::const_iterator RI =
ModuleAnalysisResults.find(PassID);
return RI == ModuleAnalysisResults.end() ? nullptr : &*RI->second;
}
void ModuleAnalysisManager::invalidateImpl(void *PassID, Module *M) {
ModuleAnalysisResults.erase(PassID);
}
void ModuleAnalysisManager::invalidateImpl(Module *M,
const PreservedAnalyses &PA) {
// FIXME: This is a total hack based on the fact that erasure doesn't
// invalidate iteration for DenseMap.
for (ModuleAnalysisResultMapT::iterator I = ModuleAnalysisResults.begin(),
E = ModuleAnalysisResults.end();
I != E; ++I)
if (I->second->invalidate(M, PA))
ModuleAnalysisResults.erase(I);
}
PreservedAnalyses FunctionPassManager::run(Function *F,
FunctionAnalysisManager *AM) {
PreservedAnalyses PA = PreservedAnalyses::all();
if (DebugPM)
dbgs() << "Starting function pass manager run.\n";
for (unsigned Idx = 0, Size = Passes.size(); Idx != Size; ++Idx) {
if (DebugPM)
dbgs() << "Running function pass: " << Passes[Idx]->name() << "\n";
PreservedAnalyses PassPA = Passes[Idx]->run(F, AM);
if (AM)
AM->invalidate(F, PassPA);
PA.intersect(std::move(PassPA));
F->getContext().yield();
}
if (DebugPM)
dbgs() << "Finished function pass manager run.\n";
return PA;
}
bool FunctionAnalysisManager::empty() const {
assert(FunctionAnalysisResults.empty() ==
FunctionAnalysisResultLists.empty() &&
"The storage and index of analysis results disagree on how many there "
"are!");
return FunctionAnalysisResults.empty();
}
void FunctionAnalysisManager::clear() {
FunctionAnalysisResults.clear();
FunctionAnalysisResultLists.clear();
}
FunctionAnalysisManager::ResultConceptT &
FunctionAnalysisManager::getResultImpl(void *PassID, Function *F) {
FunctionAnalysisResultMapT::iterator RI;
bool Inserted;
std::tie(RI, Inserted) = FunctionAnalysisResults.insert(std::make_pair(
std::make_pair(PassID, F), FunctionAnalysisResultListT::iterator()));
// If we don't have a cached result for this function, look up the pass and
// run it to produce a result, which we then add to the cache.
if (Inserted) {
FunctionAnalysisResultListT &ResultList = FunctionAnalysisResultLists[F];
ResultList.emplace_back(PassID, lookupPass(PassID).run(F, this));
RI->second = std::prev(ResultList.end());
}
return *RI->second->second;
}
FunctionAnalysisManager::ResultConceptT *
FunctionAnalysisManager::getCachedResultImpl(void *PassID, Function *F) const {
FunctionAnalysisResultMapT::const_iterator RI =
FunctionAnalysisResults.find(std::make_pair(PassID, F));
return RI == FunctionAnalysisResults.end() ? nullptr : &*RI->second->second;
}
void FunctionAnalysisManager::invalidateImpl(void *PassID, Function *F) {
FunctionAnalysisResultMapT::iterator RI =
FunctionAnalysisResults.find(std::make_pair(PassID, F));
if (RI == FunctionAnalysisResults.end())
return;
FunctionAnalysisResultLists[F].erase(RI->second);
}
void FunctionAnalysisManager::invalidateImpl(Function *F,
const PreservedAnalyses &PA) {
// Clear all the invalidated results associated specifically with this
// function.
SmallVector<void *, 8> InvalidatedPassIDs;
FunctionAnalysisResultListT &ResultsList = FunctionAnalysisResultLists[F];
for (FunctionAnalysisResultListT::iterator I = ResultsList.begin(),
E = ResultsList.end();
I != E;)
if (I->second->invalidate(F, PA)) {
InvalidatedPassIDs.push_back(I->first);
I = ResultsList.erase(I);
} else {
++I;
}
while (!InvalidatedPassIDs.empty())
FunctionAnalysisResults.erase(
std::make_pair(InvalidatedPassIDs.pop_back_val(), F));
if (ResultsList.empty())
FunctionAnalysisResultLists.erase(F);
}
char FunctionAnalysisManagerModuleProxy::PassID;
FunctionAnalysisManagerModuleProxy::Result
FunctionAnalysisManagerModuleProxy::run(Module *M) {
assert(FAM->empty() && "Function analyses ran prior to the module proxy!");
return Result(*FAM);
}
FunctionAnalysisManagerModuleProxy::Result::~Result() {
// Clear out the analysis manager if we're being destroyed -- it means we
// didn't even see an invalidate call when we got invalidated.
FAM->clear();
}
bool FunctionAnalysisManagerModuleProxy::Result::invalidate(
Module *M, const PreservedAnalyses &PA) {
// If this proxy isn't marked as preserved, then we can't even invalidate
// individual function analyses, there may be an invalid set of Function
// objects in the cache making it impossible to incrementally preserve them.
// Just clear the entire manager.
if (!PA.preserved(ID()))
FAM->clear();
// Return false to indicate that this result is still a valid proxy.
return false;
}
char ModuleAnalysisManagerFunctionProxy::PassID;