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view ir/irlandingpad.cpp @ 1479:4f7d50c744ed
Rewrite `StructLiteralExp::toElem` to store individual fields instead of
generating a constant to fill the entire struct with a single `store`.
This is much more efficient at compile time (fixing #320) and vastly reduces
the size of the emitted code. Since LLVM no longer needs to keep the data for
all fields in "registers" until the store happens, it should also be more
efficient at run time in cases where the fields aren't assigned with constants.
There's also some code clean-up by removing duplicated logic.
author | Frits van Bommel <fvbommel wxs.nl> |
---|---|
date | Sat, 06 Jun 2009 20:16:13 +0200 |
parents | 3f5ea912149d |
children | e1e93343fc11 |
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#include "gen/llvm.h" #include "gen/tollvm.h" #include "gen/irstate.h" #include "gen/runtime.h" #include "gen/logger.h" #include "gen/classes.h" #include "gen/llvmhelpers.h" #include "ir/irlandingpad.h" IRLandingPadInfo::IRLandingPadInfo(Catch* catchstmt, llvm::BasicBlock* end) : finallyBody(NULL) { target = llvm::BasicBlock::Create("catch", gIR->topfunc(), end); gIR->scope() = IRScope(target,end); // assign storage to catch var if(catchstmt->var) { // use the same storage for all exceptions that are not accessed in // nested functions #if DMDV2 if(!catchstmt->var->nestedrefs.dim) { #else if(!catchstmt->var->nestedref) { #endif assert(!catchstmt->var->ir.irLocal); catchstmt->var->ir.irLocal = new IrLocal(catchstmt->var); LLValue* catch_var = gIR->func()->landingPadInfo.getExceptionStorage(); catchstmt->var->ir.irLocal->value = gIR->ir->CreateBitCast(catch_var, getPtrToType(DtoType(catchstmt->var->type))); } // this will alloca if we haven't already and take care of nested refs DtoDeclarationExp(catchstmt->var); // the exception will only be stored in catch_var. copy it over if necessary if(catchstmt->var->ir.irLocal->value != gIR->func()->landingPadInfo.getExceptionStorage()) { LLValue* exc = gIR->ir->CreateBitCast(DtoLoad(gIR->func()->landingPadInfo.getExceptionStorage()), DtoType(catchstmt->var->type)); DtoStore(exc, catchstmt->var->ir.irLocal->value); } } // emit handler, if there is one // handler is zero for instance for 'catch { debug foo(); }' if(catchstmt->handler) catchstmt->handler->toIR(gIR); if (!gIR->scopereturned()) gIR->ir->CreateBr(end); assert(catchstmt->type); catchType = catchstmt->type->toBasetype()->isClassHandle(); assert(catchType); catchType->codegen(Type::sir); } IRLandingPadInfo::IRLandingPadInfo(Statement* finallystmt) : target(NULL), finallyBody(finallystmt), catchType(NULL) { } void IRLandingPad::addCatch(Catch* catchstmt, llvm::BasicBlock* end) { unpushed_infos.push_front(IRLandingPadInfo(catchstmt, end)); } void IRLandingPad::addFinally(Statement* finallystmt) { unpushed_infos.push_front(IRLandingPadInfo(finallystmt)); } void IRLandingPad::push(llvm::BasicBlock* inBB) { // store infos such that matches are right to left nInfos.push(infos.size()); infos.insert(infos.end(), unpushed_infos.begin(), unpushed_infos.end()); unpushed_infos.clear(); constructLandingPad(inBB); // store as invoke target padBBs.push(inBB); } void IRLandingPad::pop() { padBBs.pop(); size_t n = nInfos.top(); infos.resize(n); nInfos.pop(); } llvm::BasicBlock* IRLandingPad::get() { if(padBBs.size() == 0) return NULL; else return padBBs.top(); } void IRLandingPad::constructLandingPad(llvm::BasicBlock* inBB) { // save and rewrite scope IRScope savedscope = gIR->scope(); gIR->scope() = IRScope(inBB,savedscope.end); // eh_ptr = llvm.eh.exception(); llvm::Function* eh_exception_fn = GET_INTRINSIC_DECL(eh_exception); LLValue* eh_ptr = gIR->ir->CreateCall(eh_exception_fn); // build selector arguments LLSmallVector<LLValue*, 6> selectorargs; // put in classinfos in the right order bool hasFinally = false; std::deque<IRLandingPadInfo>::iterator it = infos.begin(), end = infos.end(); for(; it != end; ++it) { if(it->finallyBody) hasFinally = true; else { if(catchToInt.find(it->catchType) == catchToInt.end()) { int newval = 1 + catchToInt.size(); catchToInt[it->catchType] = newval; } assert(it->catchType); assert(it->catchType->ir.irStruct); selectorargs.insert(selectorargs.begin(), it->catchType->ir.irStruct->getClassInfoSymbol()); } } // if there's a finally, the eh table has to have a 0 action if(hasFinally) selectorargs.push_back(llvm::ConstantInt::get(LLType::Int32Ty, 0)); // personality fn llvm::Function* personality_fn = LLVM_D_GetRuntimeFunction(gIR->module, "_d_eh_personality"); LLValue* personality_fn_arg = gIR->ir->CreateBitCast(personality_fn, getPtrToType(LLType::Int8Ty)); selectorargs.insert(selectorargs.begin(), personality_fn_arg); // eh storage target selectorargs.insert(selectorargs.begin(), eh_ptr); // if there is a catch and some catch allocated storage, store exception object if(catchToInt.size() && catch_var) { const LLType* objectTy = DtoType(ClassDeclaration::object->type); gIR->ir->CreateStore(gIR->ir->CreateBitCast(eh_ptr, objectTy), catch_var); } // eh_sel = llvm.eh.selector(eh_ptr, cast(byte*)&_d_eh_personality, <selectorargs>); llvm::Function* eh_selector_fn; if (global.params.is64bit) eh_selector_fn = GET_INTRINSIC_DECL(eh_selector_i64); else eh_selector_fn = GET_INTRINSIC_DECL(eh_selector_i32); LLValue* eh_sel = gIR->ir->CreateCall(eh_selector_fn, selectorargs.begin(), selectorargs.end()); // emit finallys and switches that branch to catches until there are no more catches // then simply branch to the finally chain llvm::SwitchInst* switchinst = NULL; std::deque<IRLandingPadInfo>::reverse_iterator rit, rend = infos.rend(); for(rit = infos.rbegin(); rit != rend; ++rit) { // if it's a finally, emit its code if(rit->finallyBody) { if(switchinst) switchinst = NULL; // since this may be emitted multiple times // give the labels a new scope gIR->func()->pushUniqueLabelScope("finally"); rit->finallyBody->toIR(gIR); gIR->func()->popLabelScope(); } // otherwise it's a catch and we'll add a switch case else { if(!switchinst) { switchinst = gIR->ir->CreateSwitch(eh_sel, llvm::BasicBlock::Create("switchdefault", gIR->topfunc(), gIR->scopeend()), infos.size()); gIR->scope() = IRScope(switchinst->getDefaultDest(), gIR->scopeend()); } // dubious comment // catches matched first get the largest switchval, so do size - unique int llvm::ConstantInt* switchval = llvm::ConstantInt::get(DtoSize_t(), catchToInt[rit->catchType]); // and make sure we don't add the same switchval twice, may happen with nested trys if(!switchinst->findCaseValue(switchval)) switchinst->addCase(switchval, rit->target); } } // no catch matched and all finallys executed - resume unwind llvm::Function* unwind_resume_fn = LLVM_D_GetRuntimeFunction(gIR->module, "_d_eh_resume_unwind"); gIR->ir->CreateCall(unwind_resume_fn, eh_ptr); gIR->ir->CreateUnreachable(); gIR->scope() = savedscope; } LLValue* IRLandingPad::getExceptionStorage() { if(!catch_var) { Logger::println("Making new catch var"); catch_var = DtoAlloca(ClassDeclaration::object->type, "catchvar"); } return catch_var; }