// Ignore oppurtunities to avoid placing safepoints on backedges, useful for
// validation
-static cl::opt<bool> AllBackedges("spp-all-backedges", cl::init(false));
+static cl::opt<bool> AllBackedges("spp-all-backedges", cl::Hidden,
+ cl::init(false));
/// If true, do not place backedge safepoints in counted loops.
-static cl::opt<bool> SkipCounted("spp-counted", cl::init(true));
+static cl::opt<bool> SkipCounted("spp-counted", cl::Hidden, cl::init(true));
// If true, split the backedge of a loop when placing the safepoint, otherwise
// split the latch block itself. Both are useful to support for
// experimentation, but in practice, it looks like splitting the backedge
// optimizes better.
-static cl::opt<bool> SplitBackedge("spp-split-backedge", cl::init(false));
+static cl::opt<bool> SplitBackedge("spp-split-backedge", cl::Hidden,
+ cl::init(false));
// Print tracing output
-static cl::opt<bool> TraceLSP("spp-trace", cl::init(false));
+static cl::opt<bool> TraceLSP("spp-trace", cl::Hidden, cl::init(false));
namespace {
};
}
-static cl::opt<bool> NoEntry("spp-no-entry", cl::init(false));
-static cl::opt<bool> NoCall("spp-no-call", cl::init(false));
-static cl::opt<bool> NoBackedge("spp-no-backedge", cl::init(false));
+static cl::opt<bool> NoEntry("spp-no-entry", cl::Hidden, cl::init(false));
+static cl::opt<bool> NoCall("spp-no-call", cl::Hidden, cl::init(false));
+static cl::opt<bool> NoBackedge("spp-no-backedge", cl::Hidden, cl::init(false));
namespace {
struct PlaceSafepoints : public ModulePass {
static char ID; // Pass identification, replacement for typeid
- bool EnableEntrySafepoints;
- bool EnableBackedgeSafepoints;
- bool EnableCallSafepoints;
-
PlaceSafepoints() : ModulePass(ID) {
initializePlaceSafepointsPass(*PassRegistry::getPassRegistry());
- EnableEntrySafepoints = !NoEntry;
- EnableBackedgeSafepoints = !NoBackedge;
- EnableCallSafepoints = !NoCall;
}
bool runOnModule(Module &M) override {
bool modified = false;
BasicBlock *Current = Pred;
while (true) {
for (Instruction &I : *Current) {
- if (CallSite CS = &I)
+ if (auto CS = CallSite(&I))
// Note: Technically, needing a safepoint isn't quite the right
// condition here. We should instead be checking if the target method
// has an
// We need to stop going forward as soon as we see a call that can
// grow the stack (i.e. the call target has a non-zero frame
// size).
- if (CallSite CS = cursor) {
- (void)CS; // Silence an unused variable warning by gcc 4.8.2
+ if (CallSite(cursor)) {
if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(cursor)) {
// llvm.assume(...) are not really calls.
if (II->getIntrinsicID() == Intrinsic::assume) {
continue;
}
+ // llvm.frameescape() intrinsic is not a real call. The intrinsic can
+ // exist only in the entry block.
+ // Inserting a statepoint before llvm.frameescape() may split the
+ // entry block, and push the intrinsic out of the entry block.
+ if (II->getIntrinsicID() == Intrinsic::frameescape) {
+ continue;
+ }
}
break;
}
// Note: SplitBlock modifies the DT. Simply passing a Pass (which is a
// module pass) is not enough.
DT.recalculate(F);
-#ifndef NDEBUG
+
// SplitBlock updates the DT
- DT.verifyDomTree();
-#endif
+ DEBUG(DT.verifyDomTree());
return BB->getTerminator();
}
return F.getName().equals(GCSafepointPollName);
}
+/// Returns true if this function should be rewritten to include safepoint
+/// polls and parseable call sites. The main point of this function is to be
+/// an extension point for custom logic.
+static bool shouldRewriteFunction(Function &F) {
+ // TODO: This should check the GCStrategy
+ if (F.hasGC()) {
+ const std::string StatepointExampleName("statepoint-example");
+ return StatepointExampleName == F.getGC();
+ } else
+ return false;
+}
+
+// TODO: These should become properties of the GCStrategy, possibly with
+// command line overrides.
+static bool enableEntrySafepoints(Function &F) { return !NoEntry; }
+static bool enableBackedgeSafepoints(Function &F) { return !NoBackedge; }
+static bool enableCallSafepoints(Function &F) { return !NoCall; }
+
+
bool PlaceSafepoints::runOnFunction(Function &F) {
if (F.isDeclaration() || F.empty()) {
// This is a declaration, nothing to do. Must exit early to avoid crash in
return false;
}
+ if (!shouldRewriteFunction(F))
+ return false;
+
bool modified = false;
// In various bits below, we rely on the fact that uses are reachable from
std::vector<CallSite> ParsePointNeeded;
- if (EnableBackedgeSafepoints) {
+ if (enableBackedgeSafepoints(F)) {
// Construct a pass manager to run the LoopPass backedge logic. We
// need the pass manager to handle scheduling all the loop passes
// appropriately. Doing this by hand is painful and just not worth messing
// with for the moment.
legacy::FunctionPassManager FPM(F.getParent());
- bool CanAssumeCallSafepoints = EnableCallSafepoints;
+ bool CanAssumeCallSafepoints = enableCallSafepoints(F);
PlaceBackedgeSafepointsImpl *PBS =
new PlaceBackedgeSafepointsImpl(CanAssumeCallSafepoints);
FPM.add(PBS);
}
}
- if (EnableEntrySafepoints) {
+ if (enableEntrySafepoints(F)) {
DT.recalculate(F);
Instruction *term = findLocationForEntrySafepoint(F, DT);
if (!term) {
}
}
- if (EnableCallSafepoints) {
+ if (enableCallSafepoints(F)) {
DT.recalculate(F);
std::vector<CallSite> Calls;
findCallSafepoints(F, Calls);
/// NOT do explicit relocation for GC support.
static Value *ReplaceWithStatepoint(const CallSite &CS, /* to replace */
Pass *P) {
- BasicBlock *BB = CS.getInstruction()->getParent();
- Function *F = BB->getParent();
- Module *M = F->getParent();
- assert(M && "must be set");
+ assert(CS.getInstruction()->getParent()->getParent()->getParent() &&
+ "must be set");
// TODO: technically, a pass is not allowed to get functions from within a
// function pass since it might trigger a new function addition. Refactor
// this logic out to the initialization of the pass. Doesn't appear to
// matter in practice.
- // Fill in the one generic type'd argument (the function is also vararg)
- std::vector<Type *> argTypes;
- argTypes.push_back(CS.getCalledValue()->getType());
-
- Function *gc_statepoint_decl = Intrinsic::getDeclaration(
- M, Intrinsic::experimental_gc_statepoint, argTypes);
-
// Then go ahead and use the builder do actually do the inserts. We insert
// immediately before the previous instruction under the assumption that all
// arguments will be available here. We can't insert afterwards since we may
// be replacing a terminator.
- Instruction *insertBefore = CS.getInstruction();
- IRBuilder<> Builder(insertBefore);
- // First, create the statepoint (with all live ptrs as arguments).
- std::vector<llvm::Value *> args;
- // target, #call args, unused, call args..., #deopt args, deopt args..., gc args...
- Value *Target = CS.getCalledValue();
- args.push_back(Target);
- int callArgSize = CS.arg_size();
- args.push_back(
- ConstantInt::get(Type::getInt32Ty(M->getContext()), callArgSize));
- // TODO: add a 'Needs GC-rewrite' later flag
- args.push_back(ConstantInt::get(Type::getInt32Ty(M->getContext()), 0));
-
- // Copy all the arguments of the original call
- args.insert(args.end(), CS.arg_begin(), CS.arg_end());
-
- // # of deopt arguments: this pass currently does not support the
- // identification of deopt arguments. If this is interesting to you,
- // please ask on llvm-dev.
- args.push_back(ConstantInt::get(Type::getInt32Ty(M->getContext()), 0));
+ IRBuilder<> Builder(CS.getInstruction());
// Note: The gc args are not filled in at this time, that's handled by
// RewriteStatepointsForGC (which is currently under review).
// Create the statepoint given all the arguments
- Instruction *token = nullptr;
- AttributeSet return_attributes;
+ Instruction *Token = nullptr;
+ AttributeSet OriginalAttrs;
+
if (CS.isCall()) {
- CallInst *toReplace = cast<CallInst>(CS.getInstruction());
- CallInst *call =
- Builder.CreateCall(gc_statepoint_decl, args, "safepoint_token");
- call->setTailCall(toReplace->isTailCall());
- call->setCallingConv(toReplace->getCallingConv());
+ CallInst *ToReplace = cast<CallInst>(CS.getInstruction());
+ CallInst *Call = Builder.CreateGCStatepointCall(
+ CS.getCalledValue(), makeArrayRef(CS.arg_begin(), CS.arg_end()), None,
+ None, "safepoint_token");
+ Call->setTailCall(ToReplace->isTailCall());
+ Call->setCallingConv(ToReplace->getCallingConv());
// Before we have to worry about GC semantics, all attributes are legal
- AttributeSet new_attrs = toReplace->getAttributes();
- // In case if we can handle this set of sttributes - set up function attrs
- // directly on statepoint and return attrs later for gc_result intrinsic.
- call->setAttributes(new_attrs.getFnAttributes());
- return_attributes = new_attrs.getRetAttributes();
// TODO: handle param attributes
+ OriginalAttrs = ToReplace->getAttributes();
- token = call;
+ // In case if we can handle this set of attributes - set up function
+ // attributes directly on statepoint and return attributes later for
+ // gc_result intrinsic.
+ Call->setAttributes(OriginalAttrs.getFnAttributes());
- // Put the following gc_result and gc_relocate calls immediately after the
- // the old call (which we're about to delete)
- BasicBlock::iterator next(toReplace);
- assert(BB->end() != next && "not a terminator, must have next");
- next++;
- Instruction *IP = &*(next);
- Builder.SetInsertPoint(IP);
- Builder.SetCurrentDebugLocation(IP->getDebugLoc());
+ Token = Call;
+ // Put the following gc_result and gc_relocate calls immediately after the
+ // the old call (which we're about to delete).
+ assert(ToReplace->getNextNode() && "not a terminator, must have next");
+ Builder.SetInsertPoint(ToReplace->getNextNode());
+ Builder.SetCurrentDebugLocation(ToReplace->getNextNode()->getDebugLoc());
} else if (CS.isInvoke()) {
- InvokeInst *toReplace = cast<InvokeInst>(CS.getInstruction());
+ InvokeInst *ToReplace = cast<InvokeInst>(CS.getInstruction());
// Insert the new invoke into the old block. We'll remove the old one in a
// moment at which point this will become the new terminator for the
// original block.
- InvokeInst *invoke = InvokeInst::Create(
- gc_statepoint_decl, toReplace->getNormalDest(),
- toReplace->getUnwindDest(), args, "", toReplace->getParent());
- invoke->setCallingConv(toReplace->getCallingConv());
+ Builder.SetInsertPoint(ToReplace->getParent());
+ InvokeInst *Invoke = Builder.CreateGCStatepointInvoke(
+ CS.getCalledValue(), ToReplace->getNormalDest(),
+ ToReplace->getUnwindDest(), makeArrayRef(CS.arg_begin(), CS.arg_end()),
+ Builder.getInt32(0), None, "safepoint_token");
// Currently we will fail on parameter attributes and on certain
// function attributes.
- AttributeSet new_attrs = toReplace->getAttributes();
- // In case if we can handle this set of sttributes - set up function attrs
- // directly on statepoint and return attrs later for gc_result intrinsic.
- invoke->setAttributes(new_attrs.getFnAttributes());
- return_attributes = new_attrs.getRetAttributes();
+ OriginalAttrs = ToReplace->getAttributes();
+
+ // In case if we can handle this set of attributes - set up function
+ // attributes directly on statepoint and return attributes later for
+ // gc_result intrinsic.
+ Invoke->setAttributes(OriginalAttrs.getFnAttributes());
- token = invoke;
+ Token = Invoke;
// We'll insert the gc.result into the normal block
- BasicBlock *normalDest = normalizeBBForInvokeSafepoint(
- toReplace->getNormalDest(), invoke->getParent());
- Instruction *IP = &*(normalDest->getFirstInsertionPt());
- Builder.SetInsertPoint(IP);
+ BasicBlock *NormalDest = normalizeBBForInvokeSafepoint(
+ ToReplace->getNormalDest(), Invoke->getParent());
+ Builder.SetInsertPoint(NormalDest->getFirstInsertionPt());
} else {
llvm_unreachable("unexpect type of CallSite");
}
- assert(token);
+ assert(Token);
// Handle the return value of the original call - update all uses to use a
// gc_result hanging off the statepoint node we just inserted
// Only add the gc_result iff there is actually a used result
if (!CS.getType()->isVoidTy() && !CS.getInstruction()->use_empty()) {
- Instruction *gc_result = nullptr;
- std::vector<Type *> types; // one per 'any' type
- types.push_back(CS.getType()); // result type
- Intrinsic::ID Id = Intrinsic::experimental_gc_result;
- Value *gc_result_func = Intrinsic::getDeclaration(M, Id, types);
-
- std::vector<Value *> args;
- args.push_back(token);
- gc_result = Builder.CreateCall(
- gc_result_func, args,
- CS.getInstruction()->hasName() ? CS.getInstruction()->getName() : "");
-
- cast<CallInst>(gc_result)->setAttributes(return_attributes);
- return gc_result;
+ std::string TakenName =
+ CS.getInstruction()->hasName() ? CS.getInstruction()->getName() : "";
+ CallInst *GCResult = Builder.CreateGCResult(Token, CS.getType(), TakenName);
+ GCResult->setAttributes(OriginalAttrs.getRetAttributes());
+ return GCResult;
} else {
// No return value for the call.
return nullptr;
projects / oota-llvm.git / blobdiff