forked from OSchip/llvm-project
				
			
		
			
				
	
	
		
			79 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			C++
		
	
	
	
			
		
		
	
	
			79 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			C++
		
	
	
	
| //===------- ItaniumCXXABI.cpp - AST support for the Itanium C++ ABI ------===//
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| //
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| //                     The LLVM Compiler Infrastructure
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| //
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| // This file is distributed under the University of Illinois Open Source
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| // License. See LICENSE.TXT for details.
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| //
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| //===----------------------------------------------------------------------===//
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| //
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| // This provides C++ AST support targeting the Itanium C++ ABI, which is
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| // documented at:
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| //  http://www.codesourcery.com/public/cxx-abi/abi.html
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| //  http://www.codesourcery.com/public/cxx-abi/abi-eh.html
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| //
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| // It also supports the closely-related ARM C++ ABI, documented at:
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| // http://infocenter.arm.com/help/topic/com.arm.doc.ihi0041c/IHI0041C_cppabi.pdf
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| //
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| //===----------------------------------------------------------------------===//
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| 
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| #include "CXXABI.h"
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| #include "clang/AST/ASTContext.h"
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| #include "clang/AST/DeclCXX.h"
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| #include "clang/AST/RecordLayout.h"
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| #include "clang/AST/Type.h"
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| #include "clang/Basic/TargetInfo.h"
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| 
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| using namespace clang;
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| 
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| namespace {
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| class ItaniumCXXABI : public CXXABI {
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| protected:
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|   ASTContext &Context;
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| public:
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|   ItaniumCXXABI(ASTContext &Ctx) : Context(Ctx) { }
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| 
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|   std::pair<uint64_t, unsigned>
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|   getMemberPointerWidthAndAlign(const MemberPointerType *MPT) const {
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|     const TargetInfo &Target = Context.getTargetInfo();
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|     TargetInfo::IntType PtrDiff = Target.getPtrDiffType(0);
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|     uint64_t Width = Target.getTypeWidth(PtrDiff);
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|     unsigned Align = Target.getTypeAlign(PtrDiff);
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|     if (MPT->getPointeeType()->isFunctionType())
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|       Width = 2 * Width;
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|     return std::make_pair(Width, Align);
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|   }
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| 
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|   CallingConv getDefaultMethodCallConv(bool isVariadic) const {
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|     return CC_C;
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|   }
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| 
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|   // We cheat and just check that the class has a vtable pointer, and that it's
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|   // only big enough to have a vtable pointer and nothing more (or less).
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|   bool isNearlyEmpty(const CXXRecordDecl *RD) const {
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| 
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|     // Check that the class has a vtable pointer.
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|     if (!RD->isDynamicClass())
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|       return false;
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| 
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|     const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
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|     CharUnits PointerSize = 
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|       Context.toCharUnitsFromBits(Context.getTargetInfo().getPointerWidth(0));
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|     return Layout.getNonVirtualSize() == PointerSize;
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|   }
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| };
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| 
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| class ARMCXXABI : public ItaniumCXXABI {
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| public:
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|   ARMCXXABI(ASTContext &Ctx) : ItaniumCXXABI(Ctx) { }
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| };
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| }
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| 
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| CXXABI *clang::CreateItaniumCXXABI(ASTContext &Ctx) {
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|   return new ItaniumCXXABI(Ctx);
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| }
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| 
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| CXXABI *clang::CreateARMCXXABI(ASTContext &Ctx) {
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|   return new ARMCXXABI(Ctx);
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| }
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