mirrors/llvm-project
0
0
Fork 0
mirror of https://github.com/llvm/llvm-project.git synced 2025-05-14 03:26:08 +00:00
Code Issues Projects Releases Wiki Activity
llvm-project/clang/lib/CodeGen/CGObjC.cpp
Daniel Dunbar 5c7e3935f1 Rework IRgen invariant w.r.t. current insert point. 
- EmitStmt is no longer required to finish with a current insertion
   point defined (i.e. it does not need to make dummy
   blocks). Instead, it can clear the insertion point in the builder
   which indicates that the current insertion point is unreachable.
 - CodeGenFunction provides HaveInsertPoint and EnsureInsertPoint
   which respectively test if there is an insert point and ensure an
   insertion point exists (by making a dummy block).
 - Clearly mark functions in CodeGenFunction which can be called with
   no insertion point defined. Currently this is a limited set, and
   EmitStmt simply EnsureInsertPoint()s before emitting subsequent IR.

Remove EmitDummyBlock, which is no longer needed. Clients who haven't
already cleared the insertion point (typically via EmitBranch) can do
so by hand.

Remove isDummyBlock, which has effectively been renamed to
HaveInsertPoint.

The main thrust of this change is that we no longer have create dummy
blocks just to destroy them a short time later in EmitBlock in the
common case that there is no unreachable code following something like
a goto. 

Additionally, this means that we are not using the hokey condition in
isDummyBlock that a block without a name is a dummy block. Guess how
well that works when we never emit block names!

llvm-svn: 59089
2008-11-11 23:11:34 +00:00

537 lines
21 KiB
C++
Raw Blame History

//===---- CGBuiltin.cpp - Emit LLVM Code for builtins ---------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This contains code to emit Objective-C code as LLVM code.
//
//===----------------------------------------------------------------------===//
#include "CGObjCRuntime.h"
#include "CodeGenFunction.h"
#include "CodeGenModule.h"
#include "clang/AST/ASTContext.h"
#include "clang/AST/DeclObjC.h"
#include "clang/Basic/Diagnostic.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/Target/TargetData.h"
using namespace clang;
using namespace CodeGen;
/// Emits an instance of NSConstantString representing the object.
llvm::Value *CodeGenFunction::EmitObjCStringLiteral(const ObjCStringLiteral *E) {
std::string String(E->getString()->getStrData(), E->getString()->getByteLength());
llvm::Constant *C = CGM.getObjCRuntime().GenerateConstantString(String);
// FIXME: This bitcast should just be made an invariant on the Runtime.
return llvm::ConstantExpr::getBitCast(C, ConvertType(E->getType()));
}
/// Emit a selector.
llvm::Value *CodeGenFunction::EmitObjCSelectorExpr(const ObjCSelectorExpr *E) {
// Untyped selector.
// Note that this implementation allows for non-constant strings to be passed
// as arguments to @selector(). Currently, the only thing preventing this
// behaviour is the type checking in the front end.
return CGM.getObjCRuntime().GetSelector(Builder, E->getSelector());
}
llvm::Value *CodeGenFunction::EmitObjCProtocolExpr(const ObjCProtocolExpr *E) {
// FIXME: This should pass the Decl not the name.
return CGM.getObjCRuntime().GenerateProtocolRef(Builder, E->getProtocol());
}
RValue CodeGenFunction::EmitObjCMessageExpr(const ObjCMessageExpr *E) {
// Only the lookup mechanism and first two arguments of the method
// implementation vary between runtimes. We can get the receiver and
// arguments in generic code.
CGObjCRuntime &Runtime = CGM.getObjCRuntime();
const Expr *ReceiverExpr = E->getReceiver();
bool isSuperMessage = false;
bool isClassMessage = false;
// Find the receiver
llvm::Value *Receiver;
if (!ReceiverExpr) {
const ObjCInterfaceDecl *OID = E->getClassInfo().first;
// Very special case, super send in class method. The receiver is
// self (the class object) and the send uses super semantics.
if (!OID) {
assert(!strcmp(E->getClassName()->getName(), "super") &&
"Unexpected missing class interface in message send.");
isSuperMessage = true;
Receiver = LoadObjCSelf();
} else {
Receiver = Runtime.GetClass(Builder, OID);
}
isClassMessage = true;
} else if (isa<ObjCSuperExpr>(E->getReceiver())) {
isSuperMessage = true;
Receiver = LoadObjCSelf();
} else {
Receiver = EmitScalarExpr(E->getReceiver());
}
CallArgList Args;
for (CallExpr::const_arg_iterator i = E->arg_begin(), e = E->arg_end();
i != e; ++i)
Args.push_back(std::make_pair(EmitAnyExprToTemp(*i), (*i)->getType()));
if (isSuperMessage) {
// super is only valid in an Objective-C method
const ObjCMethodDecl *OMD = cast<ObjCMethodDecl>(CurFuncDecl);
return Runtime.GenerateMessageSendSuper(*this, E->getType(),
E->getSelector(),
OMD->getClassInterface(),
Receiver,
isClassMessage,
Args);
}
return Runtime.GenerateMessageSend(*this, E->getType(), E->getSelector(),
Receiver, isClassMessage, Args);
}
/// StartObjCMethod - Begin emission of an ObjCMethod. This generates
/// the LLVM function and sets the other context used by
/// CodeGenFunction.
void CodeGenFunction::StartObjCMethod(const ObjCMethodDecl *OMD) {
FunctionArgList Args;
llvm::Function *Fn = CGM.getObjCRuntime().GenerateMethod(OMD);
CGM.SetMethodAttributes(OMD, Fn);
Args.push_back(std::make_pair(OMD->getSelfDecl(),
OMD->getSelfDecl()->getType()));
Args.push_back(std::make_pair(OMD->getCmdDecl(),
OMD->getCmdDecl()->getType()));
for (unsigned i = 0, e = OMD->getNumParams(); i != e; ++i) {
ParmVarDecl *IPD = OMD->getParamDecl(i);
Args.push_back(std::make_pair(IPD, IPD->getType()));
}
StartFunction(OMD, OMD->getResultType(), Fn, Args, OMD->getLocEnd());
}
/// Generate an Objective-C method. An Objective-C method is a C function with
/// its pointer, name, and types registered in the class struture.
void CodeGenFunction::GenerateObjCMethod(const ObjCMethodDecl *OMD) {
StartObjCMethod(OMD);
EmitStmt(OMD->getBody());
FinishFunction(cast<CompoundStmt>(OMD->getBody())->getRBracLoc());
}
// FIXME: I wasn't sure about the synthesis approach. If we end up
// generating an AST for the whole body we can just fall back to
// having a GenerateFunction which takes the body Stmt.
/// GenerateObjCGetter - Generate an Objective-C property getter
/// function. The given Decl must be either an ObjCCategoryImplDecl
/// or an ObjCImplementationDecl.
void CodeGenFunction::GenerateObjCGetter(const ObjCPropertyImplDecl *PID) {
ObjCIvarDecl *Ivar = PID->getPropertyIvarDecl();
const ObjCPropertyDecl *PD = PID->getPropertyDecl();
ObjCMethodDecl *OMD = PD->getGetterMethodDecl();
assert(OMD && "Invalid call to generate getter (empty method)");
// FIXME: This is rather murky, we create this here since they will
// not have been created by Sema for us.
OMD->createImplicitParams(getContext());
StartObjCMethod(OMD);
// Determine if we should use an objc_getProperty call for
// this. Non-atomic and properties with assign semantics are
// directly evaluated, and in gc-only mode we don't need it at all.
if (CGM.getLangOptions().getGCMode() != LangOptions::GCOnly &&
PD->getSetterKind() != ObjCPropertyDecl::Assign &&
!(PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_nonatomic)) {
llvm::Value *GetPropertyFn =
CGM.getObjCRuntime().GetPropertyGetFunction();
if (!GetPropertyFn) {
CGM.ErrorUnsupported(PID, "Obj-C getter requiring atomic copy");
FinishFunction();
return;
}
// Return (ivar-type) objc_getProperty((id) self, _cmd, offset, true).
// FIXME: Can't this be simpler? This might even be worse than the
// corresponding gcc code.
CodeGenTypes &Types = CGM.getTypes();
ValueDecl *Cmd = OMD->getCmdDecl();
llvm::Value *CmdVal = Builder.CreateLoad(LocalDeclMap[Cmd], "cmd");
QualType IdTy = getContext().getObjCIdType();
llvm::Value *SelfAsId =
Builder.CreateBitCast(LoadObjCSelf(), Types.ConvertType(IdTy));
llvm::Value *Offset = EmitIvarOffset(OMD->getClassInterface(), Ivar);
llvm::Value *True =
llvm::ConstantInt::get(Types.ConvertTypeForMem(getContext().BoolTy), 1);
CallArgList Args;
Args.push_back(std::make_pair(RValue::get(SelfAsId), IdTy));
Args.push_back(std::make_pair(RValue::get(CmdVal), Cmd->getType()));
Args.push_back(std::make_pair(RValue::get(Offset), getContext().LongTy));
Args.push_back(std::make_pair(RValue::get(True), getContext().BoolTy));
RValue RV = EmitCall(GetPropertyFn, PD->getType(), Args);
// We need to fix the type here. Ivars with copy & retain are
// always objects so we don't need to worry about complex or
// aggregates.
RV = RValue::get(Builder.CreateBitCast(RV.getScalarVal(),
Types.ConvertType(PD->getType())));
EmitReturnOfRValue(RV, PD->getType());
} else {
EmitReturnOfRValue(EmitLoadOfLValue(EmitLValueForIvar(LoadObjCSelf(),
Ivar, 0),
Ivar->getType()),
PD->getType());
}
FinishFunction();
}
/// GenerateObjCSetter - Generate an Objective-C property setter
/// function. The given Decl must be either an ObjCCategoryImplDecl
/// or an ObjCImplementationDecl.
void CodeGenFunction::GenerateObjCSetter(const ObjCPropertyImplDecl *PID) {
ObjCIvarDecl *Ivar = PID->getPropertyIvarDecl();
const ObjCPropertyDecl *PD = PID->getPropertyDecl();
ObjCMethodDecl *OMD = PD->getSetterMethodDecl();
assert(OMD && "Invalid call to generate setter (empty method)");
// FIXME: This is rather murky, we create this here since they will
// not have been created by Sema for us.
OMD->createImplicitParams(getContext());
StartObjCMethod(OMD);
bool IsCopy = PD->getSetterKind() == ObjCPropertyDecl::Copy;
bool IsAtomic =
!(PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_nonatomic);
// Determine if we should use an objc_setProperty call for
// this. Properties with 'copy' semantics always use it, as do
// non-atomic properties with 'release' semantics as long as we are
// not in gc-only mode.
if (IsCopy ||
(CGM.getLangOptions().getGCMode() != LangOptions::GCOnly &&
PD->getSetterKind() == ObjCPropertyDecl::Retain)) {
llvm::Value *SetPropertyFn =
CGM.getObjCRuntime().GetPropertySetFunction();
if (!SetPropertyFn) {
CGM.ErrorUnsupported(PID, "Obj-C getter requiring atomic copy");
FinishFunction();
return;
}
// Emit objc_setProperty((id) self, _cmd, offset, arg,
// <is-atomic>, <is-copy>).
// FIXME: Can't this be simpler? This might even be worse than the
// corresponding gcc code.
CodeGenTypes &Types = CGM.getTypes();
ValueDecl *Cmd = OMD->getCmdDecl();
llvm::Value *CmdVal = Builder.CreateLoad(LocalDeclMap[Cmd], "cmd");
QualType IdTy = getContext().getObjCIdType();
llvm::Value *SelfAsId =
Builder.CreateBitCast(LoadObjCSelf(), Types.ConvertType(IdTy));
llvm::Value *Offset = EmitIvarOffset(OMD->getClassInterface(), Ivar);
llvm::Value *Arg = LocalDeclMap[OMD->getParamDecl(0)];
llvm::Value *ArgAsId =
Builder.CreateBitCast(Builder.CreateLoad(Arg, "arg"),
Types.ConvertType(IdTy));
llvm::Value *True =
llvm::ConstantInt::get(Types.ConvertTypeForMem(getContext().BoolTy), 1);
llvm::Value *False =
llvm::ConstantInt::get(Types.ConvertTypeForMem(getContext().BoolTy), 0);
CallArgList Args;
Args.push_back(std::make_pair(RValue::get(SelfAsId), IdTy));
Args.push_back(std::make_pair(RValue::get(CmdVal), Cmd->getType()));
Args.push_back(std::make_pair(RValue::get(Offset), getContext().LongTy));
Args.push_back(std::make_pair(RValue::get(ArgAsId), IdTy));
Args.push_back(std::make_pair(RValue::get(IsAtomic ? True : False),
getContext().BoolTy));
Args.push_back(std::make_pair(RValue::get(IsCopy ? True : False),
getContext().BoolTy));
EmitCall(SetPropertyFn, PD->getType(), Args);
} else {
SourceLocation Loc = PD->getLocation();
ValueDecl *Self = OMD->getSelfDecl();
ObjCIvarDecl *Ivar = PID->getPropertyIvarDecl();
DeclRefExpr Base(Self, Self->getType(), Loc);
ParmVarDecl *ArgDecl = OMD->getParamDecl(0);
DeclRefExpr Arg(ArgDecl, ArgDecl->getType(), Loc);
ObjCIvarRefExpr IvarRef(Ivar, Ivar->getType(), Loc, &Base,
true, true);
BinaryOperator Assign(&IvarRef, &Arg, BinaryOperator::Assign,
Ivar->getType(), Loc);
EmitStmt(&Assign);
}
FinishFunction();
}
llvm::Value *CodeGenFunction::LoadObjCSelf() {
const ObjCMethodDecl *OMD = cast<ObjCMethodDecl>(CurFuncDecl);
return Builder.CreateLoad(LocalDeclMap[OMD->getSelfDecl()], "self");
}
RValue CodeGenFunction::EmitObjCPropertyGet(const ObjCPropertyRefExpr *E) {
// Determine getter selector.
Selector S;
if (E->getKind() == ObjCPropertyRefExpr::MethodRef) {
S = E->getGetterMethod()->getSelector();
} else {
S = E->getProperty()->getGetterName();
}
return CGM.getObjCRuntime().
GenerateMessageSend(*this, E->getType(), S,
EmitScalarExpr(E->getBase()),
false, CallArgList());
}
void CodeGenFunction::EmitObjCPropertySet(const ObjCPropertyRefExpr *E,
RValue Src) {
Selector S;
if (E->getKind() == ObjCPropertyRefExpr::MethodRef) {
ObjCMethodDecl *Setter = E->getSetterMethod();
if (Setter) {
S = Setter->getSelector();
} else {
// FIXME: This should be diagnosed by sema.
SourceRange Range = E->getSourceRange();
CGM.getDiags().Report(getContext().getFullLoc(E->getLocStart()),
diag::err_typecheck_assign_const, 0, 0,
&Range, 1);
return;
}
} else {
S = E->getProperty()->getSetterName();
}
CallArgList Args;
Args.push_back(std::make_pair(Src, E->getType()));
CGM.getObjCRuntime().GenerateMessageSend(*this, getContext().VoidTy, S,
EmitScalarExpr(E->getBase()),
false, Args);
}
void CodeGenFunction::EmitObjCForCollectionStmt(const ObjCForCollectionStmt &S)
{
llvm::Function *EnumerationMutationFn =
CGM.getObjCRuntime().EnumerationMutationFunction();
llvm::Value *DeclAddress;
QualType ElementTy;
if (!EnumerationMutationFn) {
CGM.ErrorUnsupported(&S, "Obj-C fast enumeration for this runtime");
return;
}
if (const DeclStmt *SD = dyn_cast<DeclStmt>(S.getElement())) {
EmitStmt(SD);
assert(HaveInsertPoint() && "DeclStmt destroyed insert point!");
const ScopedDecl* D = SD->getSolitaryDecl();
ElementTy = cast<ValueDecl>(D)->getType();
DeclAddress = LocalDeclMap[D];
} else {
ElementTy = cast<Expr>(S.getElement())->getType();
DeclAddress = 0;
}
// Fast enumeration state.
QualType StateTy = getContext().getObjCFastEnumerationStateType();
llvm::AllocaInst *StatePtr = CreateTempAlloca(ConvertType(StateTy),
"state.ptr");
StatePtr->setAlignment(getContext().getTypeAlign(StateTy) >> 3);
EmitMemSetToZero(StatePtr, StateTy);
// Number of elements in the items array.
static const unsigned NumItems = 16;
// Get selector
llvm::SmallVector<IdentifierInfo*, 3> II;
II.push_back(&CGM.getContext().Idents.get("countByEnumeratingWithState"));
II.push_back(&CGM.getContext().Idents.get("objects"));
II.push_back(&CGM.getContext().Idents.get("count"));
Selector FastEnumSel = CGM.getContext().Selectors.getSelector(II.size(),
&II[0]);
QualType ItemsTy =
getContext().getConstantArrayType(getContext().getObjCIdType(),
llvm::APInt(32, NumItems),
ArrayType::Normal, 0);
llvm::Value *ItemsPtr = CreateTempAlloca(ConvertType(ItemsTy), "items.ptr");
llvm::Value *Collection = EmitScalarExpr(S.getCollection());
CallArgList Args;
Args.push_back(std::make_pair(RValue::get(StatePtr),
getContext().getPointerType(StateTy)));
Args.push_back(std::make_pair(RValue::get(ItemsPtr),
getContext().getPointerType(ItemsTy)));
const llvm::Type *UnsignedLongLTy = ConvertType(getContext().UnsignedLongTy);
llvm::Constant *Count = llvm::ConstantInt::get(UnsignedLongLTy, NumItems);
Args.push_back(std::make_pair(RValue::get(Count),
getContext().UnsignedLongTy));
RValue CountRV =
CGM.getObjCRuntime().GenerateMessageSend(*this,
getContext().UnsignedLongTy,
FastEnumSel,
Collection, false, Args);
llvm::Value *LimitPtr = CreateTempAlloca(UnsignedLongLTy, "limit.ptr");
Builder.CreateStore(CountRV.getScalarVal(), LimitPtr);
llvm::BasicBlock *NoElements = createBasicBlock("noelements");
llvm::BasicBlock *SetStartMutations = createBasicBlock("setstartmutations");
llvm::Value *Limit = Builder.CreateLoad(LimitPtr);
llvm::Value *Zero = llvm::Constant::getNullValue(UnsignedLongLTy);
llvm::Value *IsZero = Builder.CreateICmpEQ(Limit, Zero, "iszero");
Builder.CreateCondBr(IsZero, NoElements, SetStartMutations);
EmitBlock(SetStartMutations);
llvm::Value *StartMutationsPtr =
CreateTempAlloca(UnsignedLongLTy);
llvm::Value *StateMutationsPtrPtr =
Builder.CreateStructGEP(StatePtr, 2, "mutationsptr.ptr");
llvm::Value *StateMutationsPtr = Builder.CreateLoad(StateMutationsPtrPtr,
"mutationsptr");
llvm::Value *StateMutations = Builder.CreateLoad(StateMutationsPtr,
"mutations");
Builder.CreateStore(StateMutations, StartMutationsPtr);
llvm::BasicBlock *LoopStart = createBasicBlock("loopstart");
EmitBlock(LoopStart);
llvm::Value *CounterPtr = CreateTempAlloca(UnsignedLongLTy, "counter.ptr");
Builder.CreateStore(Zero, CounterPtr);
llvm::BasicBlock *LoopBody = createBasicBlock("loopbody");
EmitBlock(LoopBody);
StateMutationsPtr = Builder.CreateLoad(StateMutationsPtrPtr, "mutationsptr");
StateMutations = Builder.CreateLoad(StateMutationsPtr, "statemutations");
llvm::Value *StartMutations = Builder.CreateLoad(StartMutationsPtr,
"mutations");
llvm::Value *MutationsEqual = Builder.CreateICmpEQ(StateMutations,
StartMutations,
"tobool");
llvm::BasicBlock *WasMutated = createBasicBlock("wasmutated");
llvm::BasicBlock *WasNotMutated = createBasicBlock("wasnotmutated");
Builder.CreateCondBr(MutationsEqual, WasNotMutated, WasMutated);
EmitBlock(WasMutated);
llvm::Value *V =
Builder.CreateBitCast(Collection,
ConvertType(getContext().getObjCIdType()),
"tmp");
Builder.CreateCall(EnumerationMutationFn, V);
EmitBlock(WasNotMutated);
llvm::Value *StateItemsPtr =
Builder.CreateStructGEP(StatePtr, 1, "stateitems.ptr");
llvm::Value *Counter = Builder.CreateLoad(CounterPtr, "counter");
llvm::Value *EnumStateItems = Builder.CreateLoad(StateItemsPtr,
"stateitems");
llvm::Value *CurrentItemPtr =
Builder.CreateGEP(EnumStateItems, Counter, "currentitem.ptr");
llvm::Value *CurrentItem = Builder.CreateLoad(CurrentItemPtr, "currentitem");
// Cast the item to the right type.
CurrentItem = Builder.CreateBitCast(CurrentItem,
ConvertType(ElementTy), "tmp");
if (!DeclAddress) {
LValue LV = EmitLValue(cast<Expr>(S.getElement()));
// Set the value to null.
Builder.CreateStore(CurrentItem, LV.getAddress());
} else
Builder.CreateStore(CurrentItem, DeclAddress);
// Increment the counter.
Counter = Builder.CreateAdd(Counter,
llvm::ConstantInt::get(UnsignedLongLTy, 1));
Builder.CreateStore(Counter, CounterPtr);
llvm::BasicBlock *LoopEnd = createBasicBlock("loopend");
llvm::BasicBlock *AfterBody = createBasicBlock("afterbody");
BreakContinueStack.push_back(BreakContinue(LoopEnd, AfterBody));
EmitStmt(S.getBody());
BreakContinueStack.pop_back();
EmitBlock(AfterBody);
llvm::BasicBlock *FetchMore = createBasicBlock("fetchmore");
llvm::Value *IsLess = Builder.CreateICmpULT(Counter, Limit, "isless");
Builder.CreateCondBr(IsLess, LoopBody, FetchMore);
// Fetch more elements.
EmitBlock(FetchMore);
CountRV =
CGM.getObjCRuntime().GenerateMessageSend(*this,
getContext().UnsignedLongTy,
FastEnumSel,
Collection, false, Args);
Builder.CreateStore(CountRV.getScalarVal(), LimitPtr);
Limit = Builder.CreateLoad(LimitPtr);
IsZero = Builder.CreateICmpEQ(Limit, Zero, "iszero");
Builder.CreateCondBr(IsZero, NoElements, LoopStart);
// No more elements.
EmitBlock(NoElements);
if (!DeclAddress) {
// If the element was not a declaration, set it to be null.
LValue LV = EmitLValue(cast<Expr>(S.getElement()));
// Set the value to null.
Builder.CreateStore(llvm::Constant::getNullValue(ConvertType(ElementTy)),
LV.getAddress());
}
EmitBlock(LoopEnd);
}
void CodeGenFunction::EmitObjCAtTryStmt(const ObjCAtTryStmt &S)
{
CGM.getObjCRuntime().EmitTryStmt(*this, S);
}
void CodeGenFunction::EmitObjCAtThrowStmt(const ObjCAtThrowStmt &S)
{
CGM.getObjCRuntime().EmitThrowStmt(*this, S);
}
CGObjCRuntime::~CGObjCRuntime() {}
Reference in New Issue View Git Blame Copy Permalink