slang_rs_object_ref_count.h revision 292e00a0259ac28cac1055cb6077cf6fc7c6743c 
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_RS_OBJECT_REF_COUNT_H_  // NOLINT
18#define _FRAMEWORKS_COMPILE_SLANG_SLANG_RS_OBJECT_REF_COUNT_H_
19
20#include <list>
21#include <stack>
22
23#include "clang/AST/StmtVisitor.h"
24
25#include "slang_assert.h"
26#include "slang_rs_export_type.h"
27
28namespace clang {
29  class Expr;
30  class Stmt;
31}
32
33namespace slang {
34
35// This class provides the overall reference counting mechanism for handling
36// local variables of RS object types (rs_font, rs_allocation, ...). This
37// class ensures that appropriate functions (rsSetObject, rsClearObject) are
38// called at proper points in the object's lifetime.
39// 1) Each local object of appropriate type must be zero-initialized (to
40// prevent corruption) during subsequent rsSetObject()/rsClearObject() calls.
41// 2) Assignments using these types must also be converted into the
42// appropriate (possibly a series of) rsSetObject() calls.
43// 3) Finally, each local object must call rsClearObject() when it goes out
44// of scope.
45class RSObjectRefCount : public clang::StmtVisitor<RSObjectRefCount> {
46 private:
47  class Scope {
48   private:
49    clang::CompoundStmt *mCS;      // Associated compound statement ({ ... })
50    std::list<clang::VarDecl*> mRSO;  // Declared RS objects in this scope
51
52   public:
53    explicit Scope(clang::CompoundStmt *CS) : mCS(CS) {
54      return;
55    }
56
57    inline void addRSObject(clang::VarDecl* VD) {
58      mRSO.push_back(VD);
59      return;
60    }
61
62    void ReplaceRSObjectAssignment(clang::BinaryOperator *AS,
63                                   clang::Diagnostic *Diags);
64
65    void AppendRSObjectInit(clang::Diagnostic *Diags,
66                            clang::VarDecl *VD,
67                            clang::DeclStmt *DS,
68                            RSExportPrimitiveType::DataType DT,
69                            clang::Expr *InitExpr);
70
71    void InsertLocalVarDestructors();
72
73    static clang::Stmt *ClearRSObject(clang::VarDecl *VD);
74  };
75
76  std::stack<Scope*> mScopeStack;
77  bool RSInitFD;
78  clang::Diagnostic *mDiags;
79
80  // RSSetObjectFD and RSClearObjectFD holds FunctionDecl of rsSetObject()
81  // and rsClearObject() in the current ASTContext.
82  static clang::FunctionDecl *RSSetObjectFD[];
83  static clang::FunctionDecl *RSClearObjectFD[];
84
85  inline Scope *getCurrentScope() {
86    return mScopeStack.top();
87  }
88
89  // Initialize RSSetObjectFD and RSClearObjectFD.
90  static void GetRSRefCountingFunctions(clang::ASTContext &C);
91
92  // Return false if the type of variable declared in VD does not contain
93  // an RS object type.
94  static bool InitializeRSObject(clang::VarDecl *VD,
95                                 RSExportPrimitiveType::DataType *DT,
96                                 clang::Expr **InitExpr);
97
98  // Return a zero-initializer expr of the type DT. This processes both
99  // RS matrix type and RS object type.
100  static clang::Expr *CreateZeroInitializerForRSSpecificType(
101      RSExportPrimitiveType::DataType DT,
102      clang::ASTContext &C,
103      const clang::SourceLocation &Loc);
104
105 public:
106  RSObjectRefCount()
107      : RSInitFD(false) {
108    return;
109  }
110
111  void Init(clang::ASTContext &C, clang::Diagnostic *Diags) {
112    if (!RSInitFD) {
113      GetRSRefCountingFunctions(C);
114      mDiags = Diags;
115      RSInitFD = true;
116    }
117    return;
118  }
119
120  static clang::FunctionDecl *GetRSSetObjectFD(
121      RSExportPrimitiveType::DataType DT) {
122    slangAssert(RSExportPrimitiveType::IsRSObjectType(DT));
123    return RSSetObjectFD[(DT - RSExportPrimitiveType::FirstRSObjectType)];
124  }
125
126  static clang::FunctionDecl *GetRSSetObjectFD(const clang::Type *T) {
127    return GetRSSetObjectFD(RSExportPrimitiveType::GetRSSpecificType(T));
128  }
129
130  static clang::FunctionDecl *GetRSClearObjectFD(
131      RSExportPrimitiveType::DataType DT) {
132    slangAssert(RSExportPrimitiveType::IsRSObjectType(DT));
133    return RSClearObjectFD[(DT - RSExportPrimitiveType::FirstRSObjectType)];
134  }
135
136  static clang::FunctionDecl *GetRSClearObjectFD(const clang::Type *T) {
137    return GetRSClearObjectFD(RSExportPrimitiveType::GetRSSpecificType(T));
138  }
139
140  void VisitStmt(clang::Stmt *S);
141  void VisitDeclStmt(clang::DeclStmt *DS);
142  void VisitCompoundStmt(clang::CompoundStmt *CS);
143  void VisitBinAssign(clang::BinaryOperator *AS);
144
145  // We believe that RS objects are never involved in CompoundAssignOperator.
146  // I.e., rs_allocation foo; foo += bar;
147};
148
149}  // namespace slang
150
151#endif  // _FRAMEWORKS_COMPILE_SLANG_SLANG_RS_OBJECT_REF_COUNT_H_  NOLINT
152