Add semantic analysis for "blocks".

Highlights...

- 4 new AST nodes, BlockExpr, BlockStmtExpr, BlockExprExpr, BlockDeclRefExpr.
- Sema::ActOnBlockStart(), ActOnBlockError(), ActOnBlockStmtExpr(), ActOnBlockExprExpr(), ActOnBlockReturnStmt().

Next steps...

- hack Sema::ActOnIdentifierExpr() to deal with block decl refs.
- add attribute handler for byref decls.
- add test cases.

llvm-svn: 55710
This commit is contained in:
Steve Naroff 2008-09-03 18:15:37 +00:00
parent 62be9ad270
commit c540d66940
10 changed files with 451 additions and 2 deletions

View File

@ -1475,6 +1475,124 @@ private:
InitListExpr() : Expr(InitListExprClass, QualType()) {}
};
//===----------------------------------------------------------------------===//
// Clang Extensions
//===----------------------------------------------------------------------===//
/// BlockExpr - Common base class between BlockStmtExpr and BlockExprExpr.
class BlockExpr : public Expr {
SourceLocation CaretLocation;
llvm::SmallVector<ParmVarDecl*, 8> Args;
protected:
BlockExpr(StmtClass SC, QualType ty, SourceLocation caretloc,
ParmVarDecl **args, unsigned numargs)
: Expr(SC, ty), CaretLocation(caretloc), Args(args, args+numargs) {}
public:
SourceLocation getCaretLocation() const { return CaretLocation; }
/// getFunctionType - Return the underlying function type for this block.
const FunctionType *getFunctionType() const;
/// arg_iterator - Iterate over the ParmVarDecl's for the arguments to this
/// block.
typedef llvm::SmallVector<ParmVarDecl*, 8>::const_iterator arg_iterator;
bool arg_empty() const { return Args.empty(); }
arg_iterator arg_begin() const { return Args.begin(); }
arg_iterator arg_end() const { return Args.end(); }
static bool classof(const Stmt *T) {
return T->getStmtClass() == BlockStmtExprClass ||
T->getStmtClass() == BlockExprExprClass;
}
static bool classof(const BlockExpr *) { return true; }
};
/// BlockStmtExpr - Represent a block literal with a syntax:
/// ^{ statement-body } or ^(int arg1, float arg2){ statement-body }
class BlockStmtExpr : public BlockExpr {
CompoundStmt *Body;
public:
BlockStmtExpr(SourceLocation CaretLoc, QualType Ty, ParmVarDecl **args,
unsigned numargs, CompoundStmt *body) :
BlockExpr(BlockStmtExprClass, Ty, CaretLoc,
args, numargs), Body(body) {}
const CompoundStmt *getBody() const { return Body; }
CompoundStmt *getBody() { return Body; }
virtual SourceRange getSourceRange() const {
return SourceRange(getCaretLocation(), Body->getLocEnd());
}
static bool classof(const Stmt *T) {
return T->getStmtClass() == BlockStmtExprClass;
}
static bool classof(const BlockStmtExpr *) { return true; }
// Iterators
virtual child_iterator child_begin();
virtual child_iterator child_end();
virtual void EmitImpl(llvm::Serializer& S) const;
static BlockStmtExpr* CreateImpl(llvm::Deserializer& D, ASTContext& C);
};
/// BlockExprExpr - Represents a block literal with syntax:
/// ^(expression) or ^(int arg1, float arg2)(expression)
class BlockExprExpr : public BlockExpr {
Expr *BodyExpr;
public:
BlockExprExpr(SourceLocation CaretLoc, QualType Ty, ParmVarDecl **args,
unsigned numargs, Expr *body) :
BlockExpr(BlockExprExprClass, Ty, CaretLoc,
args, numargs), BodyExpr(body) {}
const Expr *getExpr() const { return BodyExpr; }
Expr *getExpr() { return BodyExpr; }
virtual SourceRange getSourceRange() const {
return SourceRange(getCaretLocation(), BodyExpr->getLocEnd());
}
// Iterators
virtual child_iterator child_begin();
virtual child_iterator child_end();
static bool classof(const Stmt *T) {
return T->getStmtClass() == BlockExprExprClass;
}
static bool classof(const BlockExprExpr *) { return true; }
};
/// BlockDeclRefExpr - A reference to a declared variable, function,
/// enum, etc.
class BlockDeclRefExpr : public Expr {
ValueDecl *D;
SourceLocation Loc;
bool IsByRef;
public:
BlockDeclRefExpr(ValueDecl *d, QualType t, SourceLocation l, bool ByRef) :
Expr(BlockDeclRefExprClass, t), D(d), Loc(l), IsByRef(ByRef) {}
ValueDecl *getDecl() { return D; }
const ValueDecl *getDecl() const { return D; }
virtual SourceRange getSourceRange() const { return SourceRange(Loc); }
bool isByRef() const { return IsByRef; }
static bool classof(const Stmt *T) {
return T->getStmtClass() == BlockDeclRefExprClass;
}
static bool classof(const BlockDeclRefExpr *) { return true; }
// Iterators
virtual child_iterator child_begin();
virtual child_iterator child_end();
virtual void EmitImpl(llvm::Serializer& S) const;
static BlockDeclRefExpr* CreateImpl(llvm::Deserializer& D, ASTContext& C);
};
} // end namespace clang
#endif

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@ -108,8 +108,12 @@ STMT(76, ObjCPropertyRefExpr , Expr)
// Clang Extensions.
STMT(77, OverloadExpr , Expr)
STMT(78, ShuffleVectorExpr , Expr)
STMT(79, BlockExpr , Expr)
STMT(80, BlockStmtExpr , BlockExpr)
STMT(81, BlockExprExpr , BlockExpr)
STMT(82, BlockDeclRefExpr , Expr)
LAST_EXPR(78)
LAST_EXPR(82)
#undef STMT
#undef FIRST_STMT

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@ -868,6 +868,12 @@ DIAG(err_qualified_block_pointer_type, ERROR,
"qualifier specification on block pointer type not allowed")
DIAG(err_nonfunction_block_type, ERROR,
"block pointer to non-function type is invalid")
DIAG(err_return_block_has_expr, ERROR,
"void block should not return a value")
DIAG(err_block_return_missing_expr, ERROR,
"non-void block should return a value")
DIAG(err_block_with_return_type_requires_args, ERROR,
"block with explicit return type requires argument list")
// Expressions.
DIAG(ext_sizeof_function_type, EXTENSION,
@ -1124,6 +1130,10 @@ DIAG(warn_uninit_val, WARNING, "use of uninitialized variable")
// Blocks
DIAG(err_expected_block_lbrace, ERROR,
"expected '{' in block literal")
DIAG(err_goto_in_block, ERROR,
"goto not allowed in closure literal")
DIAG(err_return_in_block_expression, ERROR,
"return not allowed in block expression literal")
// CFString checking
DIAG(err_cfstring_literal_not_string_constant, ERROR,

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@ -282,6 +282,13 @@ InitListExpr::InitListExpr(SourceLocation lbraceloc,
InitExprs.push_back(initexprs[i]);
}
/// getFunctionType - Return the underlying function type for this closure.
///
const FunctionType *BlockExpr::getFunctionType() const {
return getType()->getAsBlockPointerType()->
getPointeeType()->getAsFunctionType();
}
//===----------------------------------------------------------------------===//
// Generic Expression Routines
//===----------------------------------------------------------------------===//
@ -1432,3 +1439,18 @@ Stmt::child_iterator ObjCMessageExpr::child_end() {
return &SubExprs[0]+ARGS_START+getNumArgs();
}
// Blocks
Stmt::child_iterator BlockStmtExpr::child_begin() {
return reinterpret_cast<Stmt**>(&Body);
}
Stmt::child_iterator BlockStmtExpr::child_end() {
return reinterpret_cast<Stmt**>(&Body)+1;
}
Stmt::child_iterator BlockExprExpr::child_begin() {
return reinterpret_cast<Stmt**>(&BodyExpr);
}
Stmt::child_iterator BlockExprExpr::child_end() {
return reinterpret_cast<Stmt**>(&BodyExpr)+1;
}

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@ -874,6 +874,46 @@ void StmtPrinter::VisitObjCMessageExpr(ObjCMessageExpr *Mess) {
OS << "]";
}
void StmtPrinter::VisitBlockExpr(BlockExpr *Node) {
OS << "^";
const FunctionType *AFT = Node->getFunctionType();
if (isa<FunctionTypeNoProto>(AFT)) {
OS << "()";
} else if (!Node->arg_empty() || cast<FunctionTypeProto>(AFT)->isVariadic()) {
const FunctionTypeProto *FT = cast<FunctionTypeProto>(AFT);
OS << '(';
std::string ParamStr;
for (BlockStmtExpr::arg_iterator AI = Node->arg_begin(),
E = Node->arg_end(); AI != E; ++AI) {
if (AI != Node->arg_begin()) OS << ", ";
ParamStr = (*AI)->getName();
(*AI)->getType().getAsStringInternal(ParamStr);
OS << ParamStr;
}
if (FT->isVariadic()) {
if (!Node->arg_empty()) OS << ", ";
OS << "...";
}
OS << ')';
}
}
void StmtPrinter::VisitBlockStmtExpr(BlockStmtExpr *Node) {
VisitBlockExpr(Node);
PrintRawCompoundStmt(Node->getBody());
}
void StmtPrinter::VisitBlockExprExpr(BlockExprExpr *Node) {
VisitBlockExpr(Node);
PrintExpr(Node->getExpr());
}
void StmtPrinter::VisitBlockDeclRefExpr(BlockDeclRefExpr *Node) {
OS << Node->getDecl()->getName();
}
//===----------------------------------------------------------------------===//
// Stmt method implementations
//===----------------------------------------------------------------------===//

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@ -1108,6 +1108,38 @@ ObjCStringLiteral* ObjCStringLiteral::CreateImpl(Deserializer& D, ASTContext& C)
return new ObjCStringLiteral(String,T,L);
}
//===----------------------------------------------------------------------===//
// Serialization for Clang Extensions.
//===----------------------------------------------------------------------===//
void BlockStmtExpr::EmitImpl(Serializer& S) const {
S.Emit(getType());
S.Emit(getCaretLocation());
S.EmitOwnedPtr(Body);
}
BlockStmtExpr* BlockStmtExpr::CreateImpl(Deserializer& D, ASTContext& C) {
QualType Q = QualType::ReadVal(D);
SourceLocation L = SourceLocation::ReadVal(D);
/*CompoundStmt* BodyStmt = cast<CompoundStmt>(*/D.ReadOwnedPtr<Stmt>(C)/*)*/;
assert(0 && "Cannot deserialize BlockBlockExpr yet");
// FIXME: need to handle parameters.
//return new BlockBlockExpr(L, Q, BodyStmt);
return 0;
}
void BlockDeclRefExpr::EmitImpl(Serializer& S) const {
S.Emit(Loc);
S.Emit(getType());
S.EmitBool(false);
S.EmitPtr(getDecl());
}
BlockDeclRefExpr* BlockDeclRefExpr::CreateImpl(Deserializer& D, ASTContext& C) {
assert(0 && "Cannot deserialize BlockDeclRefExpr yet");
return 0;
}
//===----------------------------------------------------------------------===//
// C++ Serialization
//===----------------------------------------------------------------------===//

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@ -87,7 +87,7 @@ void Sema::ActOnTranslationUnitScope(SourceLocation Loc, Scope *S) {
}
Sema::Sema(Preprocessor &pp, ASTContext &ctxt, ASTConsumer &consumer)
: PP(pp), Context(ctxt), Consumer(consumer), CurContext(0) {
: PP(pp), Context(ctxt), Consumer(consumer), CurContext(0), CurBlock(0) {
// Get IdentifierInfo objects for known functions for which we
// do extra checking.

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@ -64,6 +64,7 @@ namespace clang {
class ObjCIvarDecl;
class ObjCMethodDecl;
class ObjCPropertyDecl;
struct BlockSemaInfo;
/// Sema - This implements semantic analysis and AST building for C.
class Sema : public Action {
@ -75,6 +76,10 @@ public:
/// CurContext - This is the current declaration context of parsing.
DeclContext *CurContext;
/// CurBlock - If inside of a block definition, this contains a pointer to
/// the active block object that represents it.
BlockSemaInfo *CurBlock;
/// LabelMap - This is a mapping from label identifiers to the LabelStmt for
/// it (which acts like the label decl in some ways). Forward referenced
/// labels have a LabelStmt created for them with a null location & SubStmt.
@ -408,6 +413,7 @@ public:
virtual StmtResult ActOnReturnStmt(SourceLocation ReturnLoc,
ExprTy *RetValExp);
StmtResult ActOnBlockReturnStmt(SourceLocation ReturnLoc, Expr *RetValExp);
virtual StmtResult ActOnAsmStmt(SourceLocation AsmLoc,
bool IsSimple,
@ -536,6 +542,27 @@ public:
virtual ExprResult ActOnVAArg(SourceLocation BuiltinLoc,
ExprTy *expr, TypeTy *type,
SourceLocation RPLoc);
//===------------------------- "Block" Extension ------------------------===//
/// ActOnBlockStart - This callback is invoked when a block literal is
/// started.
virtual void ActOnBlockStart(SourceLocation CaretLoc, Scope *CurScope,
Declarator &ParamInfo);
/// ActOnBlockError - If there is an error parsing a block, this callback
/// is invoked to pop the information about the block from the action impl.
virtual void ActOnBlockError(SourceLocation CaretLoc, Scope *CurScope);
/// ActOnBlockStmtExpr - This is called when the body of a block statement
/// literal was successfully completed. ^(int x){...}
virtual ExprResult ActOnBlockStmtExpr(SourceLocation CaretLoc, StmtTy *Body,
Scope *CurScope);
/// ActOnBlockExprExpr - This is called when the body of a block
/// expression literal was successfully completed. ^(int x)[foo bar: x]
virtual ExprResult ActOnBlockExprExpr(SourceLocation CaretLoc, ExprTy *Body,
Scope *CurScope);
// Act on C++ namespaces
virtual DeclTy *ActOnStartNamespaceDef(Scope *S, SourceLocation IdentLoc,
@ -960,6 +987,27 @@ public:
bool HadError() { return hadError; }
};
/// BlockSemaInfo - When a block is being parsed, this contains information
/// about the block. It is pointed to from Sema::CurBlock.
struct BlockSemaInfo {
llvm::SmallVector<ParmVarDecl*, 8> Params;
llvm::SmallPtrSet<Decl*, 4> ByRefVars;
bool hasPrototype;
bool isVariadic;
/// TheScope - This is the scope for the block itself, which contains
/// arguments etc.
Scope *TheScope;
/// ReturnType - This will get set to block result type, by looking at
/// return types, if any, in the block body.
Type *ReturnType;
/// PrevBlockInfo - If this is nested inside another block, this points
/// to the outer block.
BlockSemaInfo *PrevBlockInfo;
};
} // end namespace clang

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@ -21,6 +21,8 @@
#include "clang/Basic/Diagnostic.h"
#include "clang/Basic/SourceManager.h"
#include "clang/Basic/TargetInfo.h"
#include "clang/Parse/DeclSpec.h"
#include "clang/Parse/Scope.h"
using namespace clang;
//===----------------------------------------------------------------------===//
@ -2607,6 +2609,124 @@ Sema::ExprResult Sema::ActOnChooseExpr(SourceLocation BuiltinLoc, ExprTy *cond,
return new ChooseExpr(BuiltinLoc, CondExpr, LHSExpr, RHSExpr, resType, RPLoc);
}
//===----------------------------------------------------------------------===//
// Clang Extensions.
//===----------------------------------------------------------------------===//
/// ActOnBlockStart - This callback is invoked when a block literal is started.
void Sema::ActOnBlockStart(SourceLocation CaretLoc, Scope *BlockScope,
Declarator &ParamInfo) {
// Analyze block parameters.
BlockSemaInfo *BSI = new BlockSemaInfo();
// Add BSI to CurBlock.
BSI->PrevBlockInfo = CurBlock;
CurBlock = BSI;
BSI->ReturnType = 0;
BSI->TheScope = BlockScope;
// Analyze arguments to block.
assert(ParamInfo.getTypeObject(0).Kind == DeclaratorChunk::Function &&
"Not a function declarator!");
DeclaratorChunk::FunctionTypeInfo &FTI = ParamInfo.getTypeObject(0).Fun;
BSI->hasPrototype = FTI.hasPrototype;
BSI->isVariadic = true;
// Check for C99 6.7.5.3p10 - foo(void) is a non-varargs function that takes
// no arguments, not a function that takes a single void argument.
if (FTI.hasPrototype &&
FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 &&
(!((ParmVarDecl *)FTI.ArgInfo[0].Param)->getType().getCVRQualifiers() &&
((ParmVarDecl *)FTI.ArgInfo[0].Param)->getType()->isVoidType())) {
// empty arg list, don't push any params.
BSI->isVariadic = false;
} else if (FTI.hasPrototype) {
for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i)
BSI->Params.push_back((ParmVarDecl *)FTI.ArgInfo[i].Param);
BSI->isVariadic = FTI.isVariadic;
}
}
/// ActOnBlockError - If there is an error parsing a block, this callback
/// is invoked to pop the information about the block from the action impl.
void Sema::ActOnBlockError(SourceLocation CaretLoc, Scope *CurScope) {
// Ensure that CurBlock is deleted.
llvm::OwningPtr<BlockSemaInfo> CC(CurBlock);
// Pop off CurBlock, handle nested blocks.
CurBlock = CurBlock->PrevBlockInfo;
// FIXME: Delete the ParmVarDecl objects as well???
}
/// ActOnBlockStmtExpr - This is called when the body of a block statement
/// literal was successfully completed. ^(int x){...}
Sema::ExprResult Sema::ActOnBlockStmtExpr(SourceLocation CaretLoc, StmtTy *body,
Scope *CurScope) {
// Ensure that CurBlock is deleted.
llvm::OwningPtr<BlockSemaInfo> BSI(CurBlock);
llvm::OwningPtr<CompoundStmt> Body(static_cast<CompoundStmt*>(body));
// Pop off CurBlock, handle nested blocks.
CurBlock = CurBlock->PrevBlockInfo;
QualType RetTy = Context.VoidTy;
if (BSI->ReturnType)
RetTy = QualType(BSI->ReturnType, 0);
llvm::SmallVector<QualType, 8> ArgTypes;
for (unsigned i = 0, e = BSI->Params.size(); i != e; ++i)
ArgTypes.push_back(BSI->Params[i]->getType());
QualType BlockTy;
if (!BSI->hasPrototype)
BlockTy = Context.getFunctionTypeNoProto(RetTy);
else
BlockTy = Context.getFunctionType(RetTy, &ArgTypes[0], ArgTypes.size(),
BSI->isVariadic);
BlockTy = Context.getBlockPointerType(BlockTy);
return new BlockStmtExpr(CaretLoc, BlockTy,
&BSI->Params[0], BSI->Params.size(), Body.take());
}
/// ActOnBlockExprExpr - This is called when the body of a block
/// expression literal was successfully completed. ^(int x)[foo bar: x]
Sema::ExprResult Sema::ActOnBlockExprExpr(SourceLocation CaretLoc, ExprTy *body,
Scope *CurScope) {
// Ensure that CurBlock is deleted.
llvm::OwningPtr<BlockSemaInfo> BSI(CurBlock);
llvm::OwningPtr<Expr> Body(static_cast<Expr*>(body));
// Pop off CurBlock, handle nested blocks.
CurBlock = CurBlock->PrevBlockInfo;
if (BSI->ReturnType) {
Diag(CaretLoc, diag::err_return_in_block_expression);
return true;
}
QualType RetTy = Body->getType();
llvm::SmallVector<QualType, 8> ArgTypes;
for (unsigned i = 0, e = BSI->Params.size(); i != e; ++i)
ArgTypes.push_back(BSI->Params[i]->getType());
QualType BlockTy;
if (!BSI->hasPrototype)
BlockTy = Context.getFunctionTypeNoProto(RetTy);
else
BlockTy = Context.getFunctionType(RetTy, &ArgTypes[0], ArgTypes.size(),
BSI->isVariadic);
BlockTy = Context.getBlockPointerType(BlockTy);
return new BlockExprExpr(CaretLoc, BlockTy,
&BSI->Params[0], BSI->Params.size(), Body.take());
}
/// ExprsMatchFnType - return true if the Exprs in array Args have
/// QualTypes that match the QualTypes of the arguments of the FnType.
/// The number of arguments has already been validated to match the number of

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@ -588,6 +588,10 @@ Sema::ActOnObjCForCollectionStmt(SourceLocation ForLoc,
Action::StmtResult
Sema::ActOnGotoStmt(SourceLocation GotoLoc, SourceLocation LabelLoc,
IdentifierInfo *LabelII) {
// If we are in a block, reject all gotos for now.
if (CurBlock)
return Diag(GotoLoc, diag::err_goto_in_block);
// Look up the record for this label identifier.
LabelStmt *&LabelDecl = LabelMap[LabelII];
@ -630,10 +634,61 @@ Sema::ActOnBreakStmt(SourceLocation BreakLoc, Scope *CurScope) {
return new BreakStmt(BreakLoc);
}
/// ActOnBlockReturnStmt - Utilty routine to figure out block's return type.
///
Action::StmtResult
Sema::ActOnBlockReturnStmt(SourceLocation ReturnLoc, Expr *RetValExp) {
// If this is the first return we've seen in the block, infer the type of
// the block from it.
if (CurBlock->ReturnType == 0) {
if (RetValExp)
CurBlock->ReturnType = RetValExp->getType().getTypePtr();
else
CurBlock->ReturnType = Context.VoidTy.getTypePtr();
return new ReturnStmt(ReturnLoc, RetValExp);
}
// Otherwise, verify that this result type matches the previous one. We are
// pickier with blocks than for normal functions because we don't have GCC
// compatibility to worry about here.
if (CurBlock->ReturnType->isVoidType()) {
if (RetValExp) {
Diag(ReturnLoc, diag::err_return_block_has_expr);
delete RetValExp;
RetValExp = 0;
}
return new ReturnStmt(ReturnLoc, RetValExp);
}
if (!RetValExp) {
Diag(ReturnLoc, diag::err_block_return_missing_expr);
return true;
}
// we have a non-void block with an expression, continue checking
QualType RetValType = RetValExp->getType();
// For now, restrict multiple return statements in a block to have
// strict compatible types only.
QualType BlockQT = QualType(CurBlock->ReturnType, 0);
if (Context.getCanonicalType(BlockQT).getTypePtr()
!= Context.getCanonicalType(RetValType).getTypePtr()) {
DiagnoseAssignmentResult(Incompatible, ReturnLoc, BlockQT,
RetValType, RetValExp, "returning");
return true;
}
if (RetValExp) CheckReturnStackAddr(RetValExp, BlockQT, ReturnLoc);
return new ReturnStmt(ReturnLoc, (Expr*)RetValExp);
}
Action::StmtResult
Sema::ActOnReturnStmt(SourceLocation ReturnLoc, ExprTy *rex) {
Expr *RetValExp = static_cast<Expr *>(rex);
if (CurBlock)
return ActOnBlockReturnStmt(ReturnLoc, RetValExp);
QualType FnRetType =
getCurFunctionDecl() ? getCurFunctionDecl()->getResultType() :
getCurMethodDecl()->getResultType();