Check in LLVM r95781.
diff --git a/lib/CodeGen/CodeGenFunction.cpp b/lib/CodeGen/CodeGenFunction.cpp
new file mode 100644
index 0000000..5a4f94e
--- /dev/null
+++ b/lib/CodeGen/CodeGenFunction.cpp
@@ -0,0 +1,844 @@
+//===--- CodeGenFunction.cpp - Emit LLVM Code from ASTs for a Function ----===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This coordinates the per-function state used while generating code.
+//
+//===----------------------------------------------------------------------===//
+
+#include "CodeGenFunction.h"
+#include "CodeGenModule.h"
+#include "CGDebugInfo.h"
+#include "clang/Basic/TargetInfo.h"
+#include "clang/AST/APValue.h"
+#include "clang/AST/ASTContext.h"
+#include "clang/AST/Decl.h"
+#include "clang/AST/DeclCXX.h"
+#include "clang/AST/StmtCXX.h"
+#include "llvm/Target/TargetData.h"
+using namespace clang;
+using namespace CodeGen;
+
+CodeGenFunction::CodeGenFunction(CodeGenModule &cgm)
+ : BlockFunction(cgm, *this, Builder), CGM(cgm),
+ Target(CGM.getContext().Target),
+ Builder(cgm.getModule().getContext()),
+ DebugInfo(0), IndirectBranch(0),
+ SwitchInsn(0), CaseRangeBlock(0), InvokeDest(0),
+ CXXThisDecl(0), CXXVTTDecl(0),
+ ConditionalBranchLevel(0), TerminateHandler(0), TrapBB(0),
+ UniqueAggrDestructorCount(0) {
+ LLVMIntTy = ConvertType(getContext().IntTy);
+ LLVMPointerWidth = Target.getPointerWidth(0);
+ Exceptions = getContext().getLangOptions().Exceptions;
+ CatchUndefined = getContext().getLangOptions().CatchUndefined;
+}
+
+ASTContext &CodeGenFunction::getContext() const {
+ return CGM.getContext();
+}
+
+
+llvm::BasicBlock *CodeGenFunction::getBasicBlockForLabel(const LabelStmt *S) {
+ llvm::BasicBlock *&BB = LabelMap[S];
+ if (BB) return BB;
+
+ // Create, but don't insert, the new block.
+ return BB = createBasicBlock(S->getName());
+}
+
+llvm::Value *CodeGenFunction::GetAddrOfLocalVar(const VarDecl *VD) {
+ llvm::Value *Res = LocalDeclMap[VD];
+ assert(Res && "Invalid argument to GetAddrOfLocalVar(), no decl!");
+ return Res;
+}
+
+llvm::Constant *
+CodeGenFunction::GetAddrOfStaticLocalVar(const VarDecl *BVD) {
+ return cast<llvm::Constant>(GetAddrOfLocalVar(BVD));
+}
+
+const llvm::Type *CodeGenFunction::ConvertTypeForMem(QualType T) {
+ return CGM.getTypes().ConvertTypeForMem(T);
+}
+
+const llvm::Type *CodeGenFunction::ConvertType(QualType T) {
+ return CGM.getTypes().ConvertType(T);
+}
+
+bool CodeGenFunction::hasAggregateLLVMType(QualType T) {
+ return T->isRecordType() || T->isArrayType() || T->isAnyComplexType() ||
+ T->isMemberFunctionPointerType();
+}
+
+void CodeGenFunction::EmitReturnBlock() {
+ // For cleanliness, we try to avoid emitting the return block for
+ // simple cases.
+ llvm::BasicBlock *CurBB = Builder.GetInsertBlock();
+
+ if (CurBB) {
+ assert(!CurBB->getTerminator() && "Unexpected terminated block.");
+
+ // We have a valid insert point, reuse it if it is empty or there are no
+ // explicit jumps to the return block.
+ if (CurBB->empty() || ReturnBlock->use_empty()) {
+ ReturnBlock->replaceAllUsesWith(CurBB);
+ delete ReturnBlock;
+ } else
+ EmitBlock(ReturnBlock);
+ return;
+ }
+
+ // Otherwise, if the return block is the target of a single direct
+ // branch then we can just put the code in that block instead. This
+ // cleans up functions which started with a unified return block.
+ if (ReturnBlock->hasOneUse()) {
+ llvm::BranchInst *BI =
+ dyn_cast<llvm::BranchInst>(*ReturnBlock->use_begin());
+ if (BI && BI->isUnconditional() && BI->getSuccessor(0) == ReturnBlock) {
+ // Reset insertion point and delete the branch.
+ Builder.SetInsertPoint(BI->getParent());
+ BI->eraseFromParent();
+ delete ReturnBlock;
+ return;
+ }
+ }
+
+ // FIXME: We are at an unreachable point, there is no reason to emit the block
+ // unless it has uses. However, we still need a place to put the debug
+ // region.end for now.
+
+ EmitBlock(ReturnBlock);
+}
+
+void CodeGenFunction::FinishFunction(SourceLocation EndLoc) {
+ assert(BreakContinueStack.empty() &&
+ "mismatched push/pop in break/continue stack!");
+ assert(BlockScopes.empty() &&
+ "did not remove all blocks from block scope map!");
+ assert(CleanupEntries.empty() &&
+ "mismatched push/pop in cleanup stack!");
+
+ // Emit function epilog (to return).
+ EmitReturnBlock();
+
+ // Emit debug descriptor for function end.
+ if (CGDebugInfo *DI = getDebugInfo()) {
+ DI->setLocation(EndLoc);
+ DI->EmitRegionEnd(CurFn, Builder);
+ }
+
+ EmitFunctionEpilog(*CurFnInfo, ReturnValue);
+ EmitEndEHSpec(CurCodeDecl);
+
+ // If someone did an indirect goto, emit the indirect goto block at the end of
+ // the function.
+ if (IndirectBranch) {
+ EmitBlock(IndirectBranch->getParent());
+ Builder.ClearInsertionPoint();
+ }
+
+ // Remove the AllocaInsertPt instruction, which is just a convenience for us.
+ llvm::Instruction *Ptr = AllocaInsertPt;
+ AllocaInsertPt = 0;
+ Ptr->eraseFromParent();
+
+ // If someone took the address of a label but never did an indirect goto, we
+ // made a zero entry PHI node, which is illegal, zap it now.
+ if (IndirectBranch) {
+ llvm::PHINode *PN = cast<llvm::PHINode>(IndirectBranch->getAddress());
+ if (PN->getNumIncomingValues() == 0) {
+ PN->replaceAllUsesWith(llvm::UndefValue::get(PN->getType()));
+ PN->eraseFromParent();
+ }
+ }
+}
+
+void CodeGenFunction::StartFunction(GlobalDecl GD, QualType RetTy,
+ llvm::Function *Fn,
+ const FunctionArgList &Args,
+ SourceLocation StartLoc) {
+ const Decl *D = GD.getDecl();
+
+ DidCallStackSave = false;
+ CurCodeDecl = CurFuncDecl = D;
+ FnRetTy = RetTy;
+ CurFn = Fn;
+ assert(CurFn->isDeclaration() && "Function already has body?");
+
+ // Pass inline keyword to optimizer if it appears explicitly on any
+ // declaration.
+ if (const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(D))
+ for (FunctionDecl::redecl_iterator RI = FD->redecls_begin(),
+ RE = FD->redecls_end(); RI != RE; ++RI)
+ if (RI->isInlineSpecified()) {
+ Fn->addFnAttr(llvm::Attribute::InlineHint);
+ break;
+ }
+
+ llvm::BasicBlock *EntryBB = createBasicBlock("entry", CurFn);
+
+ // Create a marker to make it easy to insert allocas into the entryblock
+ // later. Don't create this with the builder, because we don't want it
+ // folded.
+ llvm::Value *Undef = llvm::UndefValue::get(llvm::Type::getInt32Ty(VMContext));
+ AllocaInsertPt = new llvm::BitCastInst(Undef,
+ llvm::Type::getInt32Ty(VMContext), "",
+ EntryBB);
+ if (Builder.isNamePreserving())
+ AllocaInsertPt->setName("allocapt");
+
+ ReturnBlock = createBasicBlock("return");
+
+ Builder.SetInsertPoint(EntryBB);
+
+ QualType FnType = getContext().getFunctionType(RetTy, 0, 0, false, 0);
+
+ // Emit subprogram debug descriptor.
+ if (CGDebugInfo *DI = getDebugInfo()) {
+ DI->setLocation(StartLoc);
+ DI->EmitFunctionStart(GD, FnType, CurFn, Builder);
+ }
+
+ // FIXME: Leaked.
+ // CC info is ignored, hopefully?
+ CurFnInfo = &CGM.getTypes().getFunctionInfo(FnRetTy, Args,
+ CC_Default, false);
+
+ if (RetTy->isVoidType()) {
+ // Void type; nothing to return.
+ ReturnValue = 0;
+ } else if (CurFnInfo->getReturnInfo().getKind() == ABIArgInfo::Indirect &&
+ hasAggregateLLVMType(CurFnInfo->getReturnType())) {
+ // Indirect aggregate return; emit returned value directly into sret slot.
+ // This reduces code size, and is also affects correctness in C++.
+ ReturnValue = CurFn->arg_begin();
+ } else {
+ ReturnValue = CreateTempAlloca(ConvertType(RetTy), "retval");
+ }
+
+ EmitStartEHSpec(CurCodeDecl);
+ EmitFunctionProlog(*CurFnInfo, CurFn, Args);
+
+ // If any of the arguments have a variably modified type, make sure to
+ // emit the type size.
+ for (FunctionArgList::const_iterator i = Args.begin(), e = Args.end();
+ i != e; ++i) {
+ QualType Ty = i->second;
+
+ if (Ty->isVariablyModifiedType())
+ EmitVLASize(Ty);
+ }
+}
+
+void CodeGenFunction::GenerateCode(GlobalDecl GD, llvm::Function *Fn) {
+ const FunctionDecl *FD = cast<FunctionDecl>(GD.getDecl());
+
+ // Check if we should generate debug info for this function.
+ if (CGM.getDebugInfo() && !FD->hasAttr<NoDebugAttr>())
+ DebugInfo = CGM.getDebugInfo();
+
+ FunctionArgList Args;
+
+ CurGD = GD;
+ OuterTryBlock = 0;
+ if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
+ if (MD->isInstance()) {
+ // Create the implicit 'this' decl.
+ // FIXME: I'm not entirely sure I like using a fake decl just for code
+ // generation. Maybe we can come up with a better way?
+ CXXThisDecl = ImplicitParamDecl::Create(getContext(), 0, SourceLocation(),
+ &getContext().Idents.get("this"),
+ MD->getThisType(getContext()));
+ Args.push_back(std::make_pair(CXXThisDecl, CXXThisDecl->getType()));
+
+ // Check if we need a VTT parameter as well.
+ if (CGVtableInfo::needsVTTParameter(GD)) {
+ // FIXME: The comment about using a fake decl above applies here too.
+ QualType T = getContext().getPointerType(getContext().VoidPtrTy);
+ CXXVTTDecl =
+ ImplicitParamDecl::Create(getContext(), 0, SourceLocation(),
+ &getContext().Idents.get("vtt"), T);
+ Args.push_back(std::make_pair(CXXVTTDecl, CXXVTTDecl->getType()));
+ }
+ }
+ }
+
+ if (FD->getNumParams()) {
+ const FunctionProtoType* FProto = FD->getType()->getAs<FunctionProtoType>();
+ assert(FProto && "Function def must have prototype!");
+
+ for (unsigned i = 0, e = FD->getNumParams(); i != e; ++i)
+ Args.push_back(std::make_pair(FD->getParamDecl(i),
+ FProto->getArgType(i)));
+ }
+
+ if (const CompoundStmt *S = FD->getCompoundBody()) {
+ StartFunction(GD, FD->getResultType(), Fn, Args, S->getLBracLoc());
+
+ if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(FD)) {
+ EmitCtorPrologue(CD, GD.getCtorType());
+ EmitStmt(S);
+
+ // If any of the member initializers are temporaries bound to references
+ // make sure to emit their destructors.
+ EmitCleanupBlocks(0);
+
+ } else if (const CXXDestructorDecl *DD = dyn_cast<CXXDestructorDecl>(FD)) {
+ llvm::BasicBlock *DtorEpilogue = createBasicBlock("dtor.epilogue");
+ PushCleanupBlock(DtorEpilogue);
+
+ InitializeVtablePtrs(DD->getParent());
+
+ EmitStmt(S);
+
+ CleanupBlockInfo Info = PopCleanupBlock();
+
+ assert(Info.CleanupBlock == DtorEpilogue && "Block mismatch!");
+ EmitBlock(DtorEpilogue);
+ EmitDtorEpilogue(DD, GD.getDtorType());
+
+ if (Info.SwitchBlock)
+ EmitBlock(Info.SwitchBlock);
+ if (Info.EndBlock)
+ EmitBlock(Info.EndBlock);
+ } else {
+ // Just a regular function, emit its body.
+ EmitStmt(S);
+ }
+
+ FinishFunction(S->getRBracLoc());
+ } else if (FD->isImplicit()) {
+ const CXXRecordDecl *ClassDecl =
+ cast<CXXRecordDecl>(FD->getDeclContext());
+ (void) ClassDecl;
+ if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(FD)) {
+ // FIXME: For C++0x, we want to look for implicit *definitions* of
+ // these special member functions, rather than implicit *declarations*.
+ if (CD->isCopyConstructor()) {
+ assert(!ClassDecl->hasUserDeclaredCopyConstructor() &&
+ "Cannot synthesize a non-implicit copy constructor");
+ SynthesizeCXXCopyConstructor(CD, GD.getCtorType(), Fn, Args);
+ } else if (CD->isDefaultConstructor()) {
+ assert(!ClassDecl->hasUserDeclaredConstructor() &&
+ "Cannot synthesize a non-implicit default constructor.");
+ SynthesizeDefaultConstructor(CD, GD.getCtorType(), Fn, Args);
+ } else {
+ assert(false && "Implicit constructor cannot be synthesized");
+ }
+ } else if (const CXXDestructorDecl *CD = dyn_cast<CXXDestructorDecl>(FD)) {
+ assert(!ClassDecl->hasUserDeclaredDestructor() &&
+ "Cannot synthesize a non-implicit destructor");
+ SynthesizeDefaultDestructor(CD, GD.getDtorType(), Fn, Args);
+ } else if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
+ assert(MD->isCopyAssignment() &&
+ !ClassDecl->hasUserDeclaredCopyAssignment() &&
+ "Cannot synthesize a method that is not an implicit-defined "
+ "copy constructor");
+ SynthesizeCXXCopyAssignment(MD, Fn, Args);
+ } else {
+ assert(false && "Cannot synthesize unknown implicit function");
+ }
+ } else if (const Stmt *S = FD->getBody()) {
+ if (const CXXTryStmt *TS = dyn_cast<CXXTryStmt>(S)) {
+ OuterTryBlock = TS;
+ StartFunction(GD, FD->getResultType(), Fn, Args, TS->getTryLoc());
+ EmitStmt(TS);
+ FinishFunction(TS->getEndLoc());
+ }
+ }
+
+ // Destroy the 'this' declaration.
+ if (CXXThisDecl)
+ CXXThisDecl->Destroy(getContext());
+
+ // Destroy the VTT declaration.
+ if (CXXVTTDecl)
+ CXXVTTDecl->Destroy(getContext());
+}
+
+/// ContainsLabel - Return true if the statement contains a label in it. If
+/// this statement is not executed normally, it not containing a label means
+/// that we can just remove the code.
+bool CodeGenFunction::ContainsLabel(const Stmt *S, bool IgnoreCaseStmts) {
+ // Null statement, not a label!
+ if (S == 0) return false;
+
+ // If this is a label, we have to emit the code, consider something like:
+ // if (0) { ... foo: bar(); } goto foo;
+ if (isa<LabelStmt>(S))
+ return true;
+
+ // If this is a case/default statement, and we haven't seen a switch, we have
+ // to emit the code.
+ if (isa<SwitchCase>(S) && !IgnoreCaseStmts)
+ return true;
+
+ // If this is a switch statement, we want to ignore cases below it.
+ if (isa<SwitchStmt>(S))
+ IgnoreCaseStmts = true;
+
+ // Scan subexpressions for verboten labels.
+ for (Stmt::const_child_iterator I = S->child_begin(), E = S->child_end();
+ I != E; ++I)
+ if (ContainsLabel(*I, IgnoreCaseStmts))
+ return true;
+
+ return false;
+}
+
+
+/// ConstantFoldsToSimpleInteger - If the sepcified expression does not fold to
+/// a constant, or if it does but contains a label, return 0. If it constant
+/// folds to 'true' and does not contain a label, return 1, if it constant folds
+/// to 'false' and does not contain a label, return -1.
+int CodeGenFunction::ConstantFoldsToSimpleInteger(const Expr *Cond) {
+ // FIXME: Rename and handle conversion of other evaluatable things
+ // to bool.
+ Expr::EvalResult Result;
+ if (!Cond->Evaluate(Result, getContext()) || !Result.Val.isInt() ||
+ Result.HasSideEffects)
+ return 0; // Not foldable, not integer or not fully evaluatable.
+
+ if (CodeGenFunction::ContainsLabel(Cond))
+ return 0; // Contains a label.
+
+ return Result.Val.getInt().getBoolValue() ? 1 : -1;
+}
+
+
+/// EmitBranchOnBoolExpr - Emit a branch on a boolean condition (e.g. for an if
+/// statement) to the specified blocks. Based on the condition, this might try
+/// to simplify the codegen of the conditional based on the branch.
+///
+void CodeGenFunction::EmitBranchOnBoolExpr(const Expr *Cond,
+ llvm::BasicBlock *TrueBlock,
+ llvm::BasicBlock *FalseBlock) {
+ if (const ParenExpr *PE = dyn_cast<ParenExpr>(Cond))
+ return EmitBranchOnBoolExpr(PE->getSubExpr(), TrueBlock, FalseBlock);
+
+ if (const BinaryOperator *CondBOp = dyn_cast<BinaryOperator>(Cond)) {
+ // Handle X && Y in a condition.
+ if (CondBOp->getOpcode() == BinaryOperator::LAnd) {
+ // If we have "1 && X", simplify the code. "0 && X" would have constant
+ // folded if the case was simple enough.
+ if (ConstantFoldsToSimpleInteger(CondBOp->getLHS()) == 1) {
+ // br(1 && X) -> br(X).
+ return EmitBranchOnBoolExpr(CondBOp->getRHS(), TrueBlock, FalseBlock);
+ }
+
+ // If we have "X && 1", simplify the code to use an uncond branch.
+ // "X && 0" would have been constant folded to 0.
+ if (ConstantFoldsToSimpleInteger(CondBOp->getRHS()) == 1) {
+ // br(X && 1) -> br(X).
+ return EmitBranchOnBoolExpr(CondBOp->getLHS(), TrueBlock, FalseBlock);
+ }
+
+ // Emit the LHS as a conditional. If the LHS conditional is false, we
+ // want to jump to the FalseBlock.
+ llvm::BasicBlock *LHSTrue = createBasicBlock("land.lhs.true");
+ EmitBranchOnBoolExpr(CondBOp->getLHS(), LHSTrue, FalseBlock);
+ EmitBlock(LHSTrue);
+
+ // Any temporaries created here are conditional.
+ BeginConditionalBranch();
+ EmitBranchOnBoolExpr(CondBOp->getRHS(), TrueBlock, FalseBlock);
+ EndConditionalBranch();
+
+ return;
+ } else if (CondBOp->getOpcode() == BinaryOperator::LOr) {
+ // If we have "0 || X", simplify the code. "1 || X" would have constant
+ // folded if the case was simple enough.
+ if (ConstantFoldsToSimpleInteger(CondBOp->getLHS()) == -1) {
+ // br(0 || X) -> br(X).
+ return EmitBranchOnBoolExpr(CondBOp->getRHS(), TrueBlock, FalseBlock);
+ }
+
+ // If we have "X || 0", simplify the code to use an uncond branch.
+ // "X || 1" would have been constant folded to 1.
+ if (ConstantFoldsToSimpleInteger(CondBOp->getRHS()) == -1) {
+ // br(X || 0) -> br(X).
+ return EmitBranchOnBoolExpr(CondBOp->getLHS(), TrueBlock, FalseBlock);
+ }
+
+ // Emit the LHS as a conditional. If the LHS conditional is true, we
+ // want to jump to the TrueBlock.
+ llvm::BasicBlock *LHSFalse = createBasicBlock("lor.lhs.false");
+ EmitBranchOnBoolExpr(CondBOp->getLHS(), TrueBlock, LHSFalse);
+ EmitBlock(LHSFalse);
+
+ // Any temporaries created here are conditional.
+ BeginConditionalBranch();
+ EmitBranchOnBoolExpr(CondBOp->getRHS(), TrueBlock, FalseBlock);
+ EndConditionalBranch();
+
+ return;
+ }
+ }
+
+ if (const UnaryOperator *CondUOp = dyn_cast<UnaryOperator>(Cond)) {
+ // br(!x, t, f) -> br(x, f, t)
+ if (CondUOp->getOpcode() == UnaryOperator::LNot)
+ return EmitBranchOnBoolExpr(CondUOp->getSubExpr(), FalseBlock, TrueBlock);
+ }
+
+ if (const ConditionalOperator *CondOp = dyn_cast<ConditionalOperator>(Cond)) {
+ // Handle ?: operator.
+
+ // Just ignore GNU ?: extension.
+ if (CondOp->getLHS()) {
+ // br(c ? x : y, t, f) -> br(c, br(x, t, f), br(y, t, f))
+ llvm::BasicBlock *LHSBlock = createBasicBlock("cond.true");
+ llvm::BasicBlock *RHSBlock = createBasicBlock("cond.false");
+ EmitBranchOnBoolExpr(CondOp->getCond(), LHSBlock, RHSBlock);
+ EmitBlock(LHSBlock);
+ EmitBranchOnBoolExpr(CondOp->getLHS(), TrueBlock, FalseBlock);
+ EmitBlock(RHSBlock);
+ EmitBranchOnBoolExpr(CondOp->getRHS(), TrueBlock, FalseBlock);
+ return;
+ }
+ }
+
+ // Emit the code with the fully general case.
+ llvm::Value *CondV = EvaluateExprAsBool(Cond);
+ Builder.CreateCondBr(CondV, TrueBlock, FalseBlock);
+}
+
+/// ErrorUnsupported - Print out an error that codegen doesn't support the
+/// specified stmt yet.
+void CodeGenFunction::ErrorUnsupported(const Stmt *S, const char *Type,
+ bool OmitOnError) {
+ CGM.ErrorUnsupported(S, Type, OmitOnError);
+}
+
+void CodeGenFunction::EmitMemSetToZero(llvm::Value *DestPtr, QualType Ty) {
+ const llvm::Type *BP = llvm::Type::getInt8PtrTy(VMContext);
+ if (DestPtr->getType() != BP)
+ DestPtr = Builder.CreateBitCast(DestPtr, BP, "tmp");
+
+ // Get size and alignment info for this aggregate.
+ std::pair<uint64_t, unsigned> TypeInfo = getContext().getTypeInfo(Ty);
+
+ // Don't bother emitting a zero-byte memset.
+ if (TypeInfo.first == 0)
+ return;
+
+ // FIXME: Handle variable sized types.
+ const llvm::Type *IntPtr = llvm::IntegerType::get(VMContext,
+ LLVMPointerWidth);
+
+ Builder.CreateCall4(CGM.getMemSetFn(), DestPtr,
+ llvm::Constant::getNullValue(llvm::Type::getInt8Ty(VMContext)),
+ // TypeInfo.first describes size in bits.
+ llvm::ConstantInt::get(IntPtr, TypeInfo.first/8),
+ llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext),
+ TypeInfo.second/8));
+}
+
+llvm::BlockAddress *CodeGenFunction::GetAddrOfLabel(const LabelStmt *L) {
+ // Make sure that there is a block for the indirect goto.
+ if (IndirectBranch == 0)
+ GetIndirectGotoBlock();
+
+ llvm::BasicBlock *BB = getBasicBlockForLabel(L);
+
+ // Make sure the indirect branch includes all of the address-taken blocks.
+ IndirectBranch->addDestination(BB);
+ return llvm::BlockAddress::get(CurFn, BB);
+}
+
+llvm::BasicBlock *CodeGenFunction::GetIndirectGotoBlock() {
+ // If we already made the indirect branch for indirect goto, return its block.
+ if (IndirectBranch) return IndirectBranch->getParent();
+
+ CGBuilderTy TmpBuilder(createBasicBlock("indirectgoto"));
+
+ const llvm::Type *Int8PtrTy = llvm::Type::getInt8PtrTy(VMContext);
+
+ // Create the PHI node that indirect gotos will add entries to.
+ llvm::Value *DestVal = TmpBuilder.CreatePHI(Int8PtrTy, "indirect.goto.dest");
+
+ // Create the indirect branch instruction.
+ IndirectBranch = TmpBuilder.CreateIndirectBr(DestVal);
+ return IndirectBranch->getParent();
+}
+
+llvm::Value *CodeGenFunction::GetVLASize(const VariableArrayType *VAT) {
+ llvm::Value *&SizeEntry = VLASizeMap[VAT->getSizeExpr()];
+
+ assert(SizeEntry && "Did not emit size for type");
+ return SizeEntry;
+}
+
+llvm::Value *CodeGenFunction::EmitVLASize(QualType Ty) {
+ assert(Ty->isVariablyModifiedType() &&
+ "Must pass variably modified type to EmitVLASizes!");
+
+ EnsureInsertPoint();
+
+ if (const VariableArrayType *VAT = getContext().getAsVariableArrayType(Ty)) {
+ llvm::Value *&SizeEntry = VLASizeMap[VAT->getSizeExpr()];
+
+ if (!SizeEntry) {
+ const llvm::Type *SizeTy = ConvertType(getContext().getSizeType());
+
+ // Get the element size;
+ QualType ElemTy = VAT->getElementType();
+ llvm::Value *ElemSize;
+ if (ElemTy->isVariableArrayType())
+ ElemSize = EmitVLASize(ElemTy);
+ else
+ ElemSize = llvm::ConstantInt::get(SizeTy,
+ getContext().getTypeSizeInChars(ElemTy).getQuantity());
+
+ llvm::Value *NumElements = EmitScalarExpr(VAT->getSizeExpr());
+ NumElements = Builder.CreateIntCast(NumElements, SizeTy, false, "tmp");
+
+ SizeEntry = Builder.CreateMul(ElemSize, NumElements);
+ }
+
+ return SizeEntry;
+ }
+
+ if (const ArrayType *AT = dyn_cast<ArrayType>(Ty)) {
+ EmitVLASize(AT->getElementType());
+ return 0;
+ }
+
+ const PointerType *PT = Ty->getAs<PointerType>();
+ assert(PT && "unknown VM type!");
+ EmitVLASize(PT->getPointeeType());
+ return 0;
+}
+
+llvm::Value* CodeGenFunction::EmitVAListRef(const Expr* E) {
+ if (CGM.getContext().getBuiltinVaListType()->isArrayType()) {
+ return EmitScalarExpr(E);
+ }
+ return EmitLValue(E).getAddress();
+}
+
+void CodeGenFunction::PushCleanupBlock(llvm::BasicBlock *CleanupEntryBlock,
+ llvm::BasicBlock *CleanupExitBlock,
+ llvm::BasicBlock *PreviousInvokeDest,
+ bool EHOnly) {
+ CleanupEntries.push_back(CleanupEntry(CleanupEntryBlock, CleanupExitBlock,
+ PreviousInvokeDest, EHOnly));
+}
+
+void CodeGenFunction::EmitCleanupBlocks(size_t OldCleanupStackSize) {
+ assert(CleanupEntries.size() >= OldCleanupStackSize &&
+ "Cleanup stack mismatch!");
+
+ while (CleanupEntries.size() > OldCleanupStackSize)
+ EmitCleanupBlock();
+}
+
+CodeGenFunction::CleanupBlockInfo CodeGenFunction::PopCleanupBlock() {
+ CleanupEntry &CE = CleanupEntries.back();
+
+ llvm::BasicBlock *CleanupEntryBlock = CE.CleanupEntryBlock;
+
+ std::vector<llvm::BasicBlock *> Blocks;
+ std::swap(Blocks, CE.Blocks);
+
+ std::vector<llvm::BranchInst *> BranchFixups;
+ std::swap(BranchFixups, CE.BranchFixups);
+
+ bool EHOnly = CE.EHOnly;
+
+ setInvokeDest(CE.PreviousInvokeDest);
+
+ CleanupEntries.pop_back();
+
+ // Check if any branch fixups pointed to the scope we just popped. If so,
+ // we can remove them.
+ for (size_t i = 0, e = BranchFixups.size(); i != e; ++i) {
+ llvm::BasicBlock *Dest = BranchFixups[i]->getSuccessor(0);
+ BlockScopeMap::iterator I = BlockScopes.find(Dest);
+
+ if (I == BlockScopes.end())
+ continue;
+
+ assert(I->second <= CleanupEntries.size() && "Invalid branch fixup!");
+
+ if (I->second == CleanupEntries.size()) {
+ // We don't need to do this branch fixup.
+ BranchFixups[i] = BranchFixups.back();
+ BranchFixups.pop_back();
+ i--;
+ e--;
+ continue;
+ }
+ }
+
+ llvm::BasicBlock *SwitchBlock = CE.CleanupExitBlock;
+ llvm::BasicBlock *EndBlock = 0;
+ if (!BranchFixups.empty()) {
+ if (!SwitchBlock)
+ SwitchBlock = createBasicBlock("cleanup.switch");
+ EndBlock = createBasicBlock("cleanup.end");
+
+ llvm::BasicBlock *CurBB = Builder.GetInsertBlock();
+
+ Builder.SetInsertPoint(SwitchBlock);
+
+ llvm::Value *DestCodePtr
+ = CreateTempAlloca(llvm::Type::getInt32Ty(VMContext),
+ "cleanup.dst");
+ llvm::Value *DestCode = Builder.CreateLoad(DestCodePtr, "tmp");
+
+ // Create a switch instruction to determine where to jump next.
+ llvm::SwitchInst *SI = Builder.CreateSwitch(DestCode, EndBlock,
+ BranchFixups.size());
+
+ // Restore the current basic block (if any)
+ if (CurBB) {
+ Builder.SetInsertPoint(CurBB);
+
+ // If we had a current basic block, we also need to emit an instruction
+ // to initialize the cleanup destination.
+ Builder.CreateStore(llvm::Constant::getNullValue(llvm::Type::getInt32Ty(VMContext)),
+ DestCodePtr);
+ } else
+ Builder.ClearInsertionPoint();
+
+ for (size_t i = 0, e = BranchFixups.size(); i != e; ++i) {
+ llvm::BranchInst *BI = BranchFixups[i];
+ llvm::BasicBlock *Dest = BI->getSuccessor(0);
+
+ // Fixup the branch instruction to point to the cleanup block.
+ BI->setSuccessor(0, CleanupEntryBlock);
+
+ if (CleanupEntries.empty()) {
+ llvm::ConstantInt *ID;
+
+ // Check if we already have a destination for this block.
+ if (Dest == SI->getDefaultDest())
+ ID = llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext), 0);
+ else {
+ ID = SI->findCaseDest(Dest);
+ if (!ID) {
+ // No code found, get a new unique one by using the number of
+ // switch successors.
+ ID = llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext),
+ SI->getNumSuccessors());
+ SI->addCase(ID, Dest);
+ }
+ }
+
+ // Store the jump destination before the branch instruction.
+ new llvm::StoreInst(ID, DestCodePtr, BI);
+ } else {
+ // We need to jump through another cleanup block. Create a pad block
+ // with a branch instruction that jumps to the final destination and add
+ // it as a branch fixup to the current cleanup scope.
+
+ // Create the pad block.
+ llvm::BasicBlock *CleanupPad = createBasicBlock("cleanup.pad", CurFn);
+
+ // Create a unique case ID.
+ llvm::ConstantInt *ID
+ = llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext),
+ SI->getNumSuccessors());
+
+ // Store the jump destination before the branch instruction.
+ new llvm::StoreInst(ID, DestCodePtr, BI);
+
+ // Add it as the destination.
+ SI->addCase(ID, CleanupPad);
+
+ // Create the branch to the final destination.
+ llvm::BranchInst *BI = llvm::BranchInst::Create(Dest);
+ CleanupPad->getInstList().push_back(BI);
+
+ // And add it as a branch fixup.
+ CleanupEntries.back().BranchFixups.push_back(BI);
+ }
+ }
+ }
+
+ // Remove all blocks from the block scope map.
+ for (size_t i = 0, e = Blocks.size(); i != e; ++i) {
+ assert(BlockScopes.count(Blocks[i]) &&
+ "Did not find block in scope map!");
+
+ BlockScopes.erase(Blocks[i]);
+ }
+
+ return CleanupBlockInfo(CleanupEntryBlock, SwitchBlock, EndBlock, EHOnly);
+}
+
+void CodeGenFunction::EmitCleanupBlock() {
+ CleanupBlockInfo Info = PopCleanupBlock();
+
+ if (Info.EHOnly) {
+ // FIXME: Add this to the exceptional edge
+ if (Info.CleanupBlock->getNumUses() == 0)
+ delete Info.CleanupBlock;
+ return;
+ }
+
+ llvm::BasicBlock *CurBB = Builder.GetInsertBlock();
+ if (CurBB && !CurBB->getTerminator() &&
+ Info.CleanupBlock->getNumUses() == 0) {
+ CurBB->getInstList().splice(CurBB->end(), Info.CleanupBlock->getInstList());
+ delete Info.CleanupBlock;
+ } else
+ EmitBlock(Info.CleanupBlock);
+
+ if (Info.SwitchBlock)
+ EmitBlock(Info.SwitchBlock);
+ if (Info.EndBlock)
+ EmitBlock(Info.EndBlock);
+}
+
+void CodeGenFunction::AddBranchFixup(llvm::BranchInst *BI) {
+ assert(!CleanupEntries.empty() &&
+ "Trying to add branch fixup without cleanup block!");
+
+ // FIXME: We could be more clever here and check if there's already a branch
+ // fixup for this destination and recycle it.
+ CleanupEntries.back().BranchFixups.push_back(BI);
+}
+
+void CodeGenFunction::EmitBranchThroughCleanup(llvm::BasicBlock *Dest) {
+ if (!HaveInsertPoint())
+ return;
+
+ llvm::BranchInst* BI = Builder.CreateBr(Dest);
+
+ Builder.ClearInsertionPoint();
+
+ // The stack is empty, no need to do any cleanup.
+ if (CleanupEntries.empty())
+ return;
+
+ if (!Dest->getParent()) {
+ // We are trying to branch to a block that hasn't been inserted yet.
+ AddBranchFixup(BI);
+ return;
+ }
+
+ BlockScopeMap::iterator I = BlockScopes.find(Dest);
+ if (I == BlockScopes.end()) {
+ // We are trying to jump to a block that is outside of any cleanup scope.
+ AddBranchFixup(BI);
+ return;
+ }
+
+ assert(I->second < CleanupEntries.size() &&
+ "Trying to branch into cleanup region");
+
+ if (I->second == CleanupEntries.size() - 1) {
+ // We have a branch to a block in the same scope.
+ return;
+ }
+
+ AddBranchFixup(BI);
+}