diff options
| -rw-r--r-- | lib/Core/ExternalDispatcher.cpp | 60 |
1 files changed, 36 insertions, 24 deletions
diff --git a/lib/Core/ExternalDispatcher.cpp b/lib/Core/ExternalDispatcher.cpp index 80bff188..767fafda 100644 --- a/lib/Core/ExternalDispatcher.cpp +++ b/lib/Core/ExternalDispatcher.cpp @@ -124,10 +124,10 @@ bool ExternalDispatcher::executeCall(Function *f, Instruction *i, uint64_t *args dispatchers.insert(std::make_pair(i, dispatcher)); if (dispatcher) { - // force the JIT execution engine to go ahead and build the - // function. this ensures that any errors or assertions in the - // compilation process will trigger crashes instead of being - // caught as aborts in the external function. + // Force the JIT execution engine to go ahead and build the function. This + // ensures that any errors or assertions in the compilation process will + // trigger crashes instead of being caught as aborts in the external + // function. executionEngine->recompileAndRelinkFunction(dispatcher); } } else { @@ -137,7 +137,7 @@ bool ExternalDispatcher::executeCall(Function *f, Instruction *i, uint64_t *args return runProtectedCall(dispatcher, args); } -// XXX not reentrant +// FIXME: This is not reentrant. static uint64_t *gTheArgsP; bool ExternalDispatcher::runProtectedCall(Function *f, uint64_t *args) { @@ -167,13 +167,12 @@ bool ExternalDispatcher::runProtectedCall(Function *f, uint64_t *args) { return res; } -// for performance purposes we construct the stub in such a way that -// the arguments pointer is passed through the static global variable -// gTheArgsP in this file. This is done so that the stub function -// prototype trivially matches the special cases that the JIT knows -// how to directly call. If this is not done, then the jit will end up -// generating a nullary stub just to call our stub, for every single -// function call. +// For performance purposes we construct the stub in such a way that the +// arguments pointer is passed through the static global variable gTheArgsP in +// this file. This is done so that the stub function prototype trivially matches +// the special cases that the JIT knows how to directly call. If this is not +// done, then the jit will end up generating a nullary stub just to call our +// stub, for every single function call. Function *ExternalDispatcher::createDispatcher(Function *target, Instruction *inst) { if (!resolveSymbol(target->getName())) return 0; @@ -198,28 +197,41 @@ Function *ExternalDispatcher::createDispatcher(Function *target, Instruction *in BasicBlock *dBB = BasicBlock::Create("entry", dispatcher); - Instruction *argI64sp = new IntToPtrInst(ConstantInt::get(Type::Int64Ty, (long) (void*) &gTheArgsP), - PointerType::getUnqual(PointerType::getUnqual(Type::Int64Ty)), - "argsp", - dBB); + // Get a Value* for &gTheArgsP, as an i64**. + Instruction *argI64sp = + new IntToPtrInst(ConstantInt::get(Type::Int64Ty, + (uintptr_t) (void*) &gTheArgsP), + PointerType::getUnqual(PointerType::getUnqual(Type::Int64Ty)), + "argsp", dBB); Instruction *argI64s = new LoadInst(argI64sp, "args", dBB); + + // Get the target function type. + const FunctionType *FTy = + cast<FunctionType>(cast<PointerType>(target->getType())->getElementType()); + // Each argument will be passed by writing it into gTheArgsP[i]. unsigned i = 0; for (CallSite::arg_iterator ai = cs.arg_begin(), ae = cs.arg_end(); ai!=ae; ++ai, ++i) { - Value *index = ConstantInt::get(Type::Int32Ty, i+1); - - Instruction *argI64p = GetElementPtrInst::Create(argI64s, index, "", dBB); - Instruction *argp = new BitCastInst(argI64p, - PointerType::getUnqual((*ai)->getType()), "", dBB); + // Determine the type the argument will be passed as. This accomodates for + // the corresponding code in Executor.cpp for handling calls to bitcasted + // functions. + const Type *argTy = (i < FTy->getNumParams() ? FTy->getParamType(i) : + (*ai)->getType()); + Instruction *argI64p = + GetElementPtrInst::Create(argI64s, ConstantInt::get(Type::Int32Ty, i+1), + "", dBB); + + Instruction *argp = new BitCastInst(argI64p, PointerType::getUnqual(argTy), + "", dBB); args[i] = new LoadInst(argp, "", dBB); } Instruction *result = CallInst::Create(target, args, args+i, "", dBB); - if (result->getType() != Type::VoidTy) { - Instruction *resp = new BitCastInst(argI64s, - PointerType::getUnqual(result->getType()), "", dBB); + Instruction *resp = + new BitCastInst(argI64s, PointerType::getUnqual(result->getType()), + "", dBB); new StoreInst(result, resp, dBB); } |