[cfe-commits] r173050 - in /cfe/trunk: include/clang/Serialization/ASTReader.h lib/Serialization/ASTCommon.cpp lib/Serialization/ASTCommon.h lib/Serialization/ASTReader.cpp lib/Serialization/ASTWriter.cpp

[Douglas Gregor]

On Jan 21, 2013, at 10:29 AM, Sebastian Redl <sebastian.redl at getdesigned.at> wrote:

> 
> On 21.01.2013, at 16:25, Douglas Gregor wrote:
> 
>> Author: dgregor
>> Date: Mon Jan 21 09:25:38 2013
>> New Revision: 173050
>> 
>> URL: http://llvm.org/viewvc/llvm-project?rev=173050&view=rev
>> Log:
>> Introduce a fast path for the ASTReader's name lookup within a
>> DeclContext. When the DeclContext is of a kind that can only be
>> defined once and never updated, we limit the search to the module file
>> that conatins the lookup table. Provides a 15% speedup in one
>> modules-heavy source file.
>> 
>> Modified:
>>   cfe/trunk/include/clang/Serialization/ASTReader.h
>>   cfe/trunk/lib/Serialization/ASTCommon.cpp
>>   cfe/trunk/lib/Serialization/ASTCommon.h
>>   cfe/trunk/lib/Serialization/ASTReader.cpp
>>   cfe/trunk/lib/Serialization/ASTWriter.cpp
>> 
>> Modified: cfe/trunk/lib/Serialization/ASTCommon.cpp
>> URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Serialization/ASTCommon.cpp?rev=173050&r1=173049&r2=173050&view=diff
>> ==============================================================================
>> --- cfe/trunk/lib/Serialization/ASTCommon.cpp (original)
>> +++ cfe/trunk/lib/Serialization/ASTCommon.cpp Mon Jan 21 09:25:38 2013
>> @@ -12,6 +12,7 @@
>> //===----------------------------------------------------------------------===//
>> 
>> #include "ASTCommon.h"
>> +#include "clang/AST/DeclObjC.h"
>> #include "clang/Basic/IdentifierTable.h"
>> #include "clang/Serialization/ASTDeserializationListener.h"
>> #include "llvm/ADT/StringExtras.h"
>> @@ -85,3 +86,60 @@
>>      R = llvm::HashString(II->getName(), R);
>>  return R;
>> }
>> +
>> +const Decl *serialization::getDefinitiveDeclContext(const DeclContext *DC) {
>> +  switch (DC->getDeclKind()) {
>> +  // These entities may have multiple definitions.
>> +  case Decl::TranslationUnit:
>> +  case Decl::Namespace:
>> +  case Decl::LinkageSpec:
>> +    return 0;
>> +
>> +  // C/C++ tag types can only be defined in one place.
>> +  case Decl::Enum:
>> +  case Decl::Record:
>> +    if (const TagDecl *Def = cast<TagDecl>(DC)->getDefinition())
>> +      return Def;
>> +    break;
>> +
>> +  // FIXME: These can be defined in one place... except special member
>> +  // functions and out-of-line definitions.
>> +  case Decl::CXXRecord:
>> +  case Decl::ClassTemplateSpecialization:
>> +  case Decl::ClassTemplatePartialSpecialization:
>> +    return 0;
>> +
>> +  // Each function, method, and block declaration is its own DeclContext.
>> +  case Decl::Function:
>> +  case Decl::CXXMethod:
>> +  case Decl::CXXConstructor:
>> +  case Decl::CXXDestructor:
>> +  case Decl::CXXConversion:
>> +  case Decl::ObjCMethod:
>> +  case Decl::Block:
>> +    // Objective C categories, category implementations, and class
>> +    // implementations can only be defined in one place.
>> +  case Decl::ObjCCategory:
>> +  case Decl::ObjCCategoryImpl:
>> +  case Decl::ObjCImplementation:
>> +    return cast<Decl>(DC);
>> +
>> +  case Decl::ObjCProtocol:
>> +    if (const ObjCProtocolDecl *Def
>> +          = cast<ObjCProtocolDecl>(DC)->getDefinition())
>> +      return Def;
>> +    break;
>> +
>> +  // FIXME: These are defined in one place, but properties in class extensions
>> +  // end up being back-patched into the main interface. See
>> +  // Sema::HandlePropertyInClassExtension for the offending code.
>> +  case Decl::ObjCInterface:
>> +    break;
>> +    
>> +  default:
>> +    llvm_unreachable("Unhandled DeclContext in AST reader");
>> +  }
>> +  
>> +  return 0;
>> +
>> +}
> 
> Maybe this switch could be consistent between using break and return 0 for the cases that don't have a definitive declcontext. Also, why is it called getDefinitiveDeclContext but returns a Decl?

r173171 fixes these inconsistencies, thanks!

	- Doug