1 /*
2  * Copyright 2010, The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *     http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #ifndef _FRAMEWORKS_COMPILE_SLANG_SLANG_BACKEND_H_  // NOLINT
18 #define _FRAMEWORKS_COMPILE_SLANG_SLANG_BACKEND_H_
19 
20 #include "clang/AST/ASTConsumer.h"
21 
22 #include "llvm/IR/LegacyPassManager.h"
23 
24 #include "llvm/Support/raw_ostream.h"
25 
26 #include "slang.h"
27 #include "slang_pragma_list.h"
28 #include "slang_rs_check_ast.h"
29 #include "slang_rs_foreach_lowering.h"
30 #include "slang_rs_object_ref_count.h"
31 #include "slang_version.h"
32 
33 namespace llvm {
34   class buffer_ostream;
35   class LLVMContext;
36   class NamedMDNode;
37   class Module;
38 }
39 
40 namespace clang {
41   class ASTConsumer;
42   class ASTContext;
43   class CodeGenOptions;
44   class CodeGenerator;
45   class DeclGroupRef;
46   class DiagnosticsEngine;
47   class FunctionDecl;
48   class HeaderSearchOptions;
49   class PreprocessorOptions;
50   class TagDecl;
51   class TargetOptions;
52   class VarDecl;
53 }
54 
55 namespace slang {
56 
57 class RSContext;
58 
59 class Backend : public clang::ASTConsumer {
60  private:
61   const clang::TargetOptions &mTargetOpts;
62 
63   llvm::Module *mpModule;
64 
65   // Output stream
66   llvm::raw_ostream *mpOS;
67   Slang::OutputType mOT;
68 
69   // This helps us translate Clang AST using into LLVM IR
70   clang::CodeGenerator *mGen;
71 
72   // Passes
73 
74   // Passes apply on function scope in a translation unit
75   llvm::legacy::FunctionPassManager *mPerFunctionPasses;
76   // Passes apply on module scope
77   llvm::legacy::PassManager *mPerModulePasses;
78   // Passes for code emission
79   llvm::legacy::FunctionPassManager *mCodeGenPasses;
80 
81   llvm::buffer_ostream mBufferOutStream;
82 
83   void CreateFunctionPasses();
84   void CreateModulePasses();
85   bool CreateCodeGenPasses();
86 
87   RSContext *mContext;
88 
89   clang::SourceManager &mSourceMgr;
90 
91   bool mASTPrint;
92 
93   bool mAllowRSPrefix;
94 
95   bool mIsFilterscript;
96 
97   llvm::NamedMDNode *mExportVarMetadata;
98   llvm::NamedMDNode *mExportFuncMetadata;
99   llvm::NamedMDNode *mExportForEachNameMetadata;
100   llvm::NamedMDNode *mExportForEachSignatureMetadata;
101   llvm::NamedMDNode *mExportReduceMetadata;
102   llvm::NamedMDNode *mExportTypeMetadata;
103   llvm::NamedMDNode *mRSObjectSlotsMetadata;
104 
105   RSObjectRefCount mRefCount;
106 
107   RSCheckAST mASTChecker;
108 
109   RSForEachLowering mForEachHandler;
110 
111   void AnnotateFunction(clang::FunctionDecl *FD);
112 
113   void dumpExportVarInfo(llvm::Module *M);
114   void dumpExportFunctionInfo(llvm::Module *M);
115   void dumpExportForEachInfo(llvm::Module *M);
116   void dumpExportReduceInfo(llvm::Module *M);
117   void dumpExportTypeInfo(llvm::Module *M);
118 
119   // Translates any rsForEach() or rsForEachWithOptions() calls inside the body
120   // of FD to lower-level runtime calls to rsForEachInternal(), if FD is not a
121   // kernel function itself, as indicated by isKernel being false. If isKernel
122   // is true, reports an error on any calls to rsForEach() or
123   // rsForEachWithOptions().
124   void LowerRSForEachCall(clang::FunctionDecl* FD, bool isKernel);
125 
126   // Insert explicit padding fields into struct to follow the current
127   // layout as defined by the RenderScript ABI (32-bit or 64-bit ARM).
128   //
129   // The padding does not change field offset or structure size -- it
130   // makes explicit any padding that was implicit due to the ABI.
131   // This ensures that if the frontend compiles for an ABI with
132   // stricter alignment requirements than the backend compiles for,
133   // the frontend and backend will still agree on structure layout
134   // (field offset and structure size).  This is important for 32-bit
135   // x86: The frontend compiles for 32-bit ARM ABI, in which 64-bit
136   // scalars are 64-bit aligned; but the 32-bit x86 ABI says that
137   // 64-bit scalars are only 32-bit aligned.
138   void PadStruct(clang::RecordDecl* RD);
139 
140  protected:
141   llvm::LLVMContext &mLLVMContext;
142   clang::DiagnosticsEngine &mDiagEngine;
143   const clang::CodeGenOptions &mCodeGenOpts;
144 
145   PragmaList *mPragmas;
146 
getTargetAPI()147   unsigned int getTargetAPI() const { return mContext->getTargetAPI(); }
148 
149   // TODO These are no longer virtual from base.  Look into merging into caller.
150 
151   // This handler will be invoked before Clang translates @Ctx to LLVM IR. This
152   // give you an opportunity to modified the IR in AST level (scope information,
153   // unoptimized IR, etc.). After the return from this method, slang will start
154   // translate @Ctx into LLVM IR. One should not operate on @Ctx afterwards
155   // since the changes applied on that never reflects to the LLVM module used
156   // in the final codegen.
157   void HandleTranslationUnitPre(clang::ASTContext &Ctx);
158 
159   // This handler will be invoked when Clang have converted AST tree to LLVM IR.
160   // The @M contains the resulting LLVM IR tree. After the return from this
161   // method, slang will start doing optimization and code generation for @M.
162   void HandleTranslationUnitPost(llvm::Module *M);
163 
164  public:
165   Backend(RSContext *Context,
166             clang::DiagnosticsEngine *DiagEngine,
167             const RSCCOptions &Opts,
168             const clang::HeaderSearchOptions &HeaderSearchOpts,
169             const clang::PreprocessorOptions &PreprocessorOpts,
170             const clang::CodeGenOptions &CodeGenOpts,
171             const clang::TargetOptions &TargetOpts,
172             PragmaList *Pragmas,
173             llvm::raw_ostream *OS,
174             Slang::OutputType OT,
175             clang::SourceManager &SourceMgr,
176             bool AllowRSPrefix,
177             bool IsFilterscript);
178 
179   virtual ~Backend();
180 
181   // Initialize - This is called to initialize the consumer, providing the
182   // ASTContext.
183   void Initialize(clang::ASTContext &Ctx) override;
184 
185   // TODO Clean up what should be private, protected
186   // TODO Also clean up the include files
187 
188   // HandleTopLevelDecl - Handle the specified top-level declaration.  This is
189   // called by the parser to process every top-level Decl*. Note that D can be
190   // the head of a chain of Decls (e.g. for `int a, b` the chain will have two
191   // elements). Use Decl::getNextDeclarator() to walk the chain.
192   bool HandleTopLevelDecl(clang::DeclGroupRef D) override;
193 
194   // HandleTranslationUnit - This method is called when the ASTs for entire
195   // translation unit have been parsed.
196   void HandleTranslationUnit(clang::ASTContext &Ctx) override;
197 
198   // HandleTagDeclDefinition - This callback is invoked each time a TagDecl
199   // (e.g. struct, union, enum, class) is completed.  This allows the client to
200   // hack on the type, which can occur at any point in the file (because these
201   // can be defined in declspecs).
202   void HandleTagDeclDefinition(clang::TagDecl *D) override;
203 
204   // CompleteTentativeDefinition - Callback invoked at the end of a translation
205   // unit to notify the consumer that the given tentative definition should be
206   // completed.
207   void CompleteTentativeDefinition(clang::VarDecl *D) override;
208 };
209 
210 }   // namespace slang
211 
212 #endif  // _FRAMEWORKS_COMPILE_SLANG_SLANG_BACKEND_H_  NOLINT
213