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#include "slang_rs_object_ref_count.h"
18
19#include <list>
20
21#include "clang/AST/DeclGroup.h"
22#include "clang/AST/Expr.h"
23#include "clang/AST/NestedNameSpecifier.h"
24#include "clang/AST/OperationKinds.h"
25#include "clang/AST/Stmt.h"
26#include "clang/AST/StmtVisitor.h"
27
28#include "slang_assert.h"
29#include "slang_rs.h"
30#include "slang_rs_ast_replace.h"
31#include "slang_rs_export_type.h"
32
33namespace slang {
34
35/* Even though those two arrays are of size DataTypeMax, only entries that
36 * correspond to object types will be set.
37 */
38clang::FunctionDecl *
39RSObjectRefCount::RSSetObjectFD[DataTypeMax];
40clang::FunctionDecl *
41RSObjectRefCount::RSClearObjectFD[DataTypeMax];
42
43void RSObjectRefCount::GetRSRefCountingFunctions(clang::ASTContext &C) {
44  for (unsigned i = 0; i < DataTypeMax; i++) {
45    RSSetObjectFD[i] = NULL;
46    RSClearObjectFD[i] = NULL;
47  }
48
49  clang::TranslationUnitDecl *TUDecl = C.getTranslationUnitDecl();
50
51  for (clang::DeclContext::decl_iterator I = TUDecl->decls_begin(),
52          E = TUDecl->decls_end(); I != E; I++) {
53    if ((I->getKind() >= clang::Decl::firstFunction) &&
54        (I->getKind() <= clang::Decl::lastFunction)) {
55      clang::FunctionDecl *FD = static_cast<clang::FunctionDecl*>(*I);
56
57      // points to RSSetObjectFD or RSClearObjectFD
58      clang::FunctionDecl **RSObjectFD;
59
60      if (FD->getName() == "rsSetObject") {
61        slangAssert((FD->getNumParams() == 2) &&
62                    "Invalid rsSetObject function prototype (# params)");
63        RSObjectFD = RSSetObjectFD;
64      } else if (FD->getName() == "rsClearObject") {
65        slangAssert((FD->getNumParams() == 1) &&
66                    "Invalid rsClearObject function prototype (# params)");
67        RSObjectFD = RSClearObjectFD;
68      } else {
69        continue;
70      }
71
72      const clang::ParmVarDecl *PVD = FD->getParamDecl(0);
73      clang::QualType PVT = PVD->getOriginalType();
74      // The first parameter must be a pointer like rs_allocation*
75      slangAssert(PVT->isPointerType() &&
76          "Invalid rs{Set,Clear}Object function prototype (pointer param)");
77
78      // The rs object type passed to the FD
79      clang::QualType RST = PVT->getPointeeType();
80      DataType DT = RSExportPrimitiveType::GetRSSpecificType(RST.getTypePtr());
81      slangAssert(RSExportPrimitiveType::IsRSObjectType(DT)
82             && "must be RS object type");
83
84      if (DT >= 0 && DT < DataTypeMax) {
85          RSObjectFD[DT] = FD;
86      } else {
87          slangAssert(false && "incorrect type");
88      }
89    }
90  }
91}
92
93namespace {
94
95// This function constructs a new CompoundStmt from the input StmtList.
96static clang::CompoundStmt* BuildCompoundStmt(clang::ASTContext &C,
97      std::list<clang::Stmt*> &StmtList, clang::SourceLocation Loc) {
98  unsigned NewStmtCount = StmtList.size();
99  unsigned CompoundStmtCount = 0;
100
101  clang::Stmt **CompoundStmtList;
102  CompoundStmtList = new clang::Stmt*[NewStmtCount];
103
104  std::list<clang::Stmt*>::const_iterator I = StmtList.begin();
105  std::list<clang::Stmt*>::const_iterator E = StmtList.end();
106  for ( ; I != E; I++) {
107    CompoundStmtList[CompoundStmtCount++] = *I;
108  }
109  slangAssert(CompoundStmtCount == NewStmtCount);
110
111  clang::CompoundStmt *CS = new(C) clang::CompoundStmt(
112      C, llvm::makeArrayRef(CompoundStmtList, CompoundStmtCount), Loc, Loc);
113
114  delete [] CompoundStmtList;
115
116  return CS;
117}
118
119static void AppendAfterStmt(clang::ASTContext &C,
120                            clang::CompoundStmt *CS,
121                            clang::Stmt *S,
122                            std::list<clang::Stmt*> &StmtList) {
123  slangAssert(CS);
124  clang::CompoundStmt::body_iterator bI = CS->body_begin();
125  clang::CompoundStmt::body_iterator bE = CS->body_end();
126  clang::Stmt **UpdatedStmtList =
127      new clang::Stmt*[CS->size() + StmtList.size()];
128
129  unsigned UpdatedStmtCount = 0;
130  unsigned Once = 0;
131  for ( ; bI != bE; bI++) {
132    if (!S && ((*bI)->getStmtClass() == clang::Stmt::ReturnStmtClass)) {
133      // If we come across a return here, we don't have anything we can
134      // reasonably replace. We should have already inserted our destructor
135      // code in the proper spot, so we just clean up and return.
136      delete [] UpdatedStmtList;
137
138      return;
139    }
140
141    UpdatedStmtList[UpdatedStmtCount++] = *bI;
142
143    if ((*bI == S) && !Once) {
144      Once++;
145      std::list<clang::Stmt*>::const_iterator I = StmtList.begin();
146      std::list<clang::Stmt*>::const_iterator E = StmtList.end();
147      for ( ; I != E; I++) {
148        UpdatedStmtList[UpdatedStmtCount++] = *I;
149      }
150    }
151  }
152  slangAssert(Once <= 1);
153
154  // When S is NULL, we are appending to the end of the CompoundStmt.
155  if (!S) {
156    slangAssert(Once == 0);
157    std::list<clang::Stmt*>::const_iterator I = StmtList.begin();
158    std::list<clang::Stmt*>::const_iterator E = StmtList.end();
159    for ( ; I != E; I++) {
160      UpdatedStmtList[UpdatedStmtCount++] = *I;
161    }
162  }
163
164  CS->setStmts(C, UpdatedStmtList, UpdatedStmtCount);
165
166  delete [] UpdatedStmtList;
167}
168
169// This class visits a compound statement and inserts DtorStmt
170// in proper locations. This includes inserting it before any
171// return statement in any sub-block, at the end of the logical enclosing
172// scope (compound statement), and/or before any break/continue statement that
173// would resume outside the declared scope. We will not handle the case for
174// goto statements that leave a local scope.
175//
176// To accomplish these goals, it collects a list of sub-Stmt's that
177// correspond to scope exit points. It then uses an RSASTReplace visitor to
178// transform the AST, inserting appropriate destructors before each of those
179// sub-Stmt's (and also before the exit of the outermost containing Stmt for
180// the scope).
181class DestructorVisitor : public clang::StmtVisitor<DestructorVisitor> {
182 private:
183  clang::ASTContext &mCtx;
184
185  // The loop depth of the currently visited node.
186  int mLoopDepth;
187
188  // The switch statement depth of the currently visited node.
189  // Note that this is tracked separately from the loop depth because
190  // SwitchStmt-contained ContinueStmt's should have destructors for the
191  // corresponding loop scope.
192  int mSwitchDepth;
193
194  // The outermost statement block that we are currently visiting.
195  // This should always be a CompoundStmt.
196  clang::Stmt *mOuterStmt;
197
198  // The destructor to execute for this scope/variable.
199  clang::Stmt* mDtorStmt;
200
201  // The stack of statements which should be replaced by a compound statement
202  // containing the new destructor call followed by the original Stmt.
203  std::stack<clang::Stmt*> mReplaceStmtStack;
204
205  // The source location for the variable declaration that we are trying to
206  // insert destructors for. Note that InsertDestructors() will not generate
207  // destructor calls for source locations that occur lexically before this
208  // location.
209  clang::SourceLocation mVarLoc;
210
211 public:
212  DestructorVisitor(clang::ASTContext &C,
213                    clang::Stmt* OuterStmt,
214                    clang::Stmt* DtorStmt,
215                    clang::SourceLocation VarLoc);
216
217  // This code walks the collected list of Stmts to replace and actually does
218  // the replacement. It also finishes up by appending the destructor to the
219  // current outermost CompoundStmt.
220  void InsertDestructors() {
221    clang::Stmt *S = NULL;
222    clang::SourceManager &SM = mCtx.getSourceManager();
223    std::list<clang::Stmt *> StmtList;
224    StmtList.push_back(mDtorStmt);
225
226    while (!mReplaceStmtStack.empty()) {
227      S = mReplaceStmtStack.top();
228      mReplaceStmtStack.pop();
229
230      // Skip all source locations that occur before the variable's
231      // declaration, since it won't have been initialized yet.
232      if (SM.isBeforeInTranslationUnit(S->getLocStart(), mVarLoc)) {
233        continue;
234      }
235
236      StmtList.push_back(S);
237      clang::CompoundStmt *CS =
238          BuildCompoundStmt(mCtx, StmtList, S->getLocEnd());
239      StmtList.pop_back();
240
241      RSASTReplace R(mCtx);
242      R.ReplaceStmt(mOuterStmt, S, CS);
243    }
244    clang::CompoundStmt *CS =
245      llvm::dyn_cast<clang::CompoundStmt>(mOuterStmt);
246    slangAssert(CS);
247    AppendAfterStmt(mCtx, CS, NULL, StmtList);
248  }
249
250  void VisitStmt(clang::Stmt *S);
251  void VisitCompoundStmt(clang::CompoundStmt *CS);
252
253  void VisitBreakStmt(clang::BreakStmt *BS);
254  void VisitCaseStmt(clang::CaseStmt *CS);
255  void VisitContinueStmt(clang::ContinueStmt *CS);
256  void VisitDefaultStmt(clang::DefaultStmt *DS);
257  void VisitDoStmt(clang::DoStmt *DS);
258  void VisitForStmt(clang::ForStmt *FS);
259  void VisitIfStmt(clang::IfStmt *IS);
260  void VisitReturnStmt(clang::ReturnStmt *RS);
261  void VisitSwitchCase(clang::SwitchCase *SC);
262  void VisitSwitchStmt(clang::SwitchStmt *SS);
263  void VisitWhileStmt(clang::WhileStmt *WS);
264};
265
266DestructorVisitor::DestructorVisitor(clang::ASTContext &C,
267                         clang::Stmt *OuterStmt,
268                         clang::Stmt *DtorStmt,
269                         clang::SourceLocation VarLoc)
270  : mCtx(C),
271    mLoopDepth(0),
272    mSwitchDepth(0),
273    mOuterStmt(OuterStmt),
274    mDtorStmt(DtorStmt),
275    mVarLoc(VarLoc) {
276}
277
278void DestructorVisitor::VisitStmt(clang::Stmt *S) {
279  for (clang::Stmt::child_iterator I = S->child_begin(), E = S->child_end();
280       I != E;
281       I++) {
282    if (clang::Stmt *Child = *I) {
283      Visit(Child);
284    }
285  }
286}
287
288void DestructorVisitor::VisitCompoundStmt(clang::CompoundStmt *CS) {
289  VisitStmt(CS);
290}
291
292void DestructorVisitor::VisitBreakStmt(clang::BreakStmt *BS) {
293  VisitStmt(BS);
294  if ((mLoopDepth == 0) && (mSwitchDepth == 0)) {
295    mReplaceStmtStack.push(BS);
296  }
297}
298
299void DestructorVisitor::VisitCaseStmt(clang::CaseStmt *CS) {
300  VisitStmt(CS);
301}
302
303void DestructorVisitor::VisitContinueStmt(clang::ContinueStmt *CS) {
304  VisitStmt(CS);
305  if (mLoopDepth == 0) {
306    // Switch statements can have nested continues.
307    mReplaceStmtStack.push(CS);
308  }
309}
310
311void DestructorVisitor::VisitDefaultStmt(clang::DefaultStmt *DS) {
312  VisitStmt(DS);
313}
314
315void DestructorVisitor::VisitDoStmt(clang::DoStmt *DS) {
316  mLoopDepth++;
317  VisitStmt(DS);
318  mLoopDepth--;
319}
320
321void DestructorVisitor::VisitForStmt(clang::ForStmt *FS) {
322  mLoopDepth++;
323  VisitStmt(FS);
324  mLoopDepth--;
325}
326
327void DestructorVisitor::VisitIfStmt(clang::IfStmt *IS) {
328  VisitStmt(IS);
329}
330
331void DestructorVisitor::VisitReturnStmt(clang::ReturnStmt *RS) {
332  mReplaceStmtStack.push(RS);
333}
334
335void DestructorVisitor::VisitSwitchCase(clang::SwitchCase *SC) {
336  slangAssert(false && "Both case and default have specialized handlers");
337  VisitStmt(SC);
338}
339
340void DestructorVisitor::VisitSwitchStmt(clang::SwitchStmt *SS) {
341  mSwitchDepth++;
342  VisitStmt(SS);
343  mSwitchDepth--;
344}
345
346void DestructorVisitor::VisitWhileStmt(clang::WhileStmt *WS) {
347  mLoopDepth++;
348  VisitStmt(WS);
349  mLoopDepth--;
350}
351
352clang::Expr *ClearSingleRSObject(clang::ASTContext &C,
353                                 clang::Expr *RefRSVar,
354                                 clang::SourceLocation Loc) {
355  slangAssert(RefRSVar);
356  const clang::Type *T = RefRSVar->getType().getTypePtr();
357  slangAssert(!T->isArrayType() &&
358              "Should not be destroying arrays with this function");
359
360  clang::FunctionDecl *ClearObjectFD = RSObjectRefCount::GetRSClearObjectFD(T);
361  slangAssert((ClearObjectFD != NULL) &&
362              "rsClearObject doesn't cover all RS object types");
363
364  clang::QualType ClearObjectFDType = ClearObjectFD->getType();
365  clang::QualType ClearObjectFDArgType =
366      ClearObjectFD->getParamDecl(0)->getOriginalType();
367
368  // Example destructor for "rs_font localFont;"
369  //
370  // (CallExpr 'void'
371  //   (ImplicitCastExpr 'void (*)(rs_font *)' <FunctionToPointerDecay>
372  //     (DeclRefExpr 'void (rs_font *)' FunctionDecl='rsClearObject'))
373  //   (UnaryOperator 'rs_font *' prefix '&'
374  //     (DeclRefExpr 'rs_font':'rs_font' Var='localFont')))
375
376  // Get address of targeted RS object
377  clang::Expr *AddrRefRSVar =
378      new(C) clang::UnaryOperator(RefRSVar,
379                                  clang::UO_AddrOf,
380                                  ClearObjectFDArgType,
381                                  clang::VK_RValue,
382                                  clang::OK_Ordinary,
383                                  Loc);
384
385  clang::Expr *RefRSClearObjectFD =
386      clang::DeclRefExpr::Create(C,
387                                 clang::NestedNameSpecifierLoc(),
388                                 clang::SourceLocation(),
389                                 ClearObjectFD,
390                                 false,
391                                 ClearObjectFD->getLocation(),
392                                 ClearObjectFDType,
393                                 clang::VK_RValue,
394                                 NULL);
395
396  clang::Expr *RSClearObjectFP =
397      clang::ImplicitCastExpr::Create(C,
398                                      C.getPointerType(ClearObjectFDType),
399                                      clang::CK_FunctionToPointerDecay,
400                                      RefRSClearObjectFD,
401                                      NULL,
402                                      clang::VK_RValue);
403
404  llvm::SmallVector<clang::Expr*, 1> ArgList;
405  ArgList.push_back(AddrRefRSVar);
406
407  clang::CallExpr *RSClearObjectCall =
408      new(C) clang::CallExpr(C,
409                             RSClearObjectFP,
410                             ArgList,
411                             ClearObjectFD->getCallResultType(),
412                             clang::VK_RValue,
413                             Loc);
414
415  return RSClearObjectCall;
416}
417
418static int ArrayDim(const clang::Type *T) {
419  if (!T || !T->isArrayType()) {
420    return 0;
421  }
422
423  const clang::ConstantArrayType *CAT =
424    static_cast<const clang::ConstantArrayType *>(T);
425  return static_cast<int>(CAT->getSize().getSExtValue());
426}
427
428static clang::Stmt *ClearStructRSObject(
429    clang::ASTContext &C,
430    clang::DeclContext *DC,
431    clang::Expr *RefRSStruct,
432    clang::SourceLocation StartLoc,
433    clang::SourceLocation Loc);
434
435static clang::Stmt *ClearArrayRSObject(
436    clang::ASTContext &C,
437    clang::DeclContext *DC,
438    clang::Expr *RefRSArr,
439    clang::SourceLocation StartLoc,
440    clang::SourceLocation Loc) {
441  const clang::Type *BaseType = RefRSArr->getType().getTypePtr();
442  slangAssert(BaseType->isArrayType());
443
444  int NumArrayElements = ArrayDim(BaseType);
445  // Actually extract out the base RS object type for use later
446  BaseType = BaseType->getArrayElementTypeNoTypeQual();
447
448  clang::Stmt *StmtArray[2] = {NULL};
449  int StmtCtr = 0;
450
451  if (NumArrayElements <= 0) {
452    return NULL;
453  }
454
455  // Example destructor loop for "rs_font fontArr[10];"
456  //
457  // (CompoundStmt
458  //   (DeclStmt "int rsIntIter")
459  //   (ForStmt
460  //     (BinaryOperator 'int' '='
461  //       (DeclRefExpr 'int' Var='rsIntIter')
462  //       (IntegerLiteral 'int' 0))
463  //     (BinaryOperator 'int' '<'
464  //       (DeclRefExpr 'int' Var='rsIntIter')
465  //       (IntegerLiteral 'int' 10)
466  //     NULL << CondVar >>
467  //     (UnaryOperator 'int' postfix '++'
468  //       (DeclRefExpr 'int' Var='rsIntIter'))
469  //     (CallExpr 'void'
470  //       (ImplicitCastExpr 'void (*)(rs_font *)' <FunctionToPointerDecay>
471  //         (DeclRefExpr 'void (rs_font *)' FunctionDecl='rsClearObject'))
472  //       (UnaryOperator 'rs_font *' prefix '&'
473  //         (ArraySubscriptExpr 'rs_font':'rs_font'
474  //           (ImplicitCastExpr 'rs_font *' <ArrayToPointerDecay>
475  //             (DeclRefExpr 'rs_font [10]' Var='fontArr'))
476  //           (DeclRefExpr 'int' Var='rsIntIter')))))))
477
478  // Create helper variable for iterating through elements
479  clang::IdentifierInfo& II = C.Idents.get("rsIntIter");
480  clang::VarDecl *IIVD =
481      clang::VarDecl::Create(C,
482                             DC,
483                             StartLoc,
484                             Loc,
485                             &II,
486                             C.IntTy,
487                             C.getTrivialTypeSourceInfo(C.IntTy),
488                             clang::SC_None);
489  clang::Decl *IID = (clang::Decl *)IIVD;
490
491  clang::DeclGroupRef DGR = clang::DeclGroupRef::Create(C, &IID, 1);
492  StmtArray[StmtCtr++] = new(C) clang::DeclStmt(DGR, Loc, Loc);
493
494  // Form the actual destructor loop
495  // for (Init; Cond; Inc)
496  //   RSClearObjectCall;
497
498  // Init -> "rsIntIter = 0"
499  clang::DeclRefExpr *RefrsIntIter =
500      clang::DeclRefExpr::Create(C,
501                                 clang::NestedNameSpecifierLoc(),
502                                 clang::SourceLocation(),
503                                 IIVD,
504                                 false,
505                                 Loc,
506                                 C.IntTy,
507                                 clang::VK_RValue,
508                                 NULL);
509
510  clang::Expr *Int0 = clang::IntegerLiteral::Create(C,
511      llvm::APInt(C.getTypeSize(C.IntTy), 0), C.IntTy, Loc);
512
513  clang::BinaryOperator *Init =
514      new(C) clang::BinaryOperator(RefrsIntIter,
515                                   Int0,
516                                   clang::BO_Assign,
517                                   C.IntTy,
518                                   clang::VK_RValue,
519                                   clang::OK_Ordinary,
520                                   Loc,
521                                   false);
522
523  // Cond -> "rsIntIter < NumArrayElements"
524  clang::Expr *NumArrayElementsExpr = clang::IntegerLiteral::Create(C,
525      llvm::APInt(C.getTypeSize(C.IntTy), NumArrayElements), C.IntTy, Loc);
526
527  clang::BinaryOperator *Cond =
528      new(C) clang::BinaryOperator(RefrsIntIter,
529                                   NumArrayElementsExpr,
530                                   clang::BO_LT,
531                                   C.IntTy,
532                                   clang::VK_RValue,
533                                   clang::OK_Ordinary,
534                                   Loc,
535                                   false);
536
537  // Inc -> "rsIntIter++"
538  clang::UnaryOperator *Inc =
539      new(C) clang::UnaryOperator(RefrsIntIter,
540                                  clang::UO_PostInc,
541                                  C.IntTy,
542                                  clang::VK_RValue,
543                                  clang::OK_Ordinary,
544                                  Loc);
545
546  // Body -> "rsClearObject(&VD[rsIntIter]);"
547  // Destructor loop operates on individual array elements
548
549  clang::Expr *RefRSArrPtr =
550      clang::ImplicitCastExpr::Create(C,
551          C.getPointerType(BaseType->getCanonicalTypeInternal()),
552          clang::CK_ArrayToPointerDecay,
553          RefRSArr,
554          NULL,
555          clang::VK_RValue);
556
557  clang::Expr *RefRSArrPtrSubscript =
558      new(C) clang::ArraySubscriptExpr(RefRSArrPtr,
559                                       RefrsIntIter,
560                                       BaseType->getCanonicalTypeInternal(),
561                                       clang::VK_RValue,
562                                       clang::OK_Ordinary,
563                                       Loc);
564
565  DataType DT = RSExportPrimitiveType::GetRSSpecificType(BaseType);
566
567  clang::Stmt *RSClearObjectCall = NULL;
568  if (BaseType->isArrayType()) {
569    RSClearObjectCall =
570        ClearArrayRSObject(C, DC, RefRSArrPtrSubscript, StartLoc, Loc);
571  } else if (DT == DataTypeUnknown) {
572    RSClearObjectCall =
573        ClearStructRSObject(C, DC, RefRSArrPtrSubscript, StartLoc, Loc);
574  } else {
575    RSClearObjectCall = ClearSingleRSObject(C, RefRSArrPtrSubscript, Loc);
576  }
577
578  clang::ForStmt *DestructorLoop =
579      new(C) clang::ForStmt(C,
580                            Init,
581                            Cond,
582                            NULL,  // no condVar
583                            Inc,
584                            RSClearObjectCall,
585                            Loc,
586                            Loc,
587                            Loc);
588
589  StmtArray[StmtCtr++] = DestructorLoop;
590  slangAssert(StmtCtr == 2);
591
592  clang::CompoundStmt *CS = new(C) clang::CompoundStmt(
593      C, llvm::makeArrayRef(StmtArray, StmtCtr), Loc, Loc);
594
595  return CS;
596}
597
598static unsigned CountRSObjectTypes(clang::ASTContext &C,
599                                   const clang::Type *T,
600                                   clang::SourceLocation Loc) {
601  slangAssert(T);
602  unsigned RSObjectCount = 0;
603
604  if (T->isArrayType()) {
605    return CountRSObjectTypes(C, T->getArrayElementTypeNoTypeQual(), Loc);
606  }
607
608  DataType DT = RSExportPrimitiveType::GetRSSpecificType(T);
609  if (DT != DataTypeUnknown) {
610    return (RSExportPrimitiveType::IsRSObjectType(DT) ? 1 : 0);
611  }
612
613  if (T->isUnionType()) {
614    clang::RecordDecl *RD = T->getAsUnionType()->getDecl();
615    RD = RD->getDefinition();
616    for (clang::RecordDecl::field_iterator FI = RD->field_begin(),
617           FE = RD->field_end();
618         FI != FE;
619         FI++) {
620      const clang::FieldDecl *FD = *FI;
621      const clang::Type *FT = RSExportType::GetTypeOfDecl(FD);
622      if (CountRSObjectTypes(C, FT, Loc)) {
623        slangAssert(false && "can't have unions with RS object types!");
624        return 0;
625      }
626    }
627  }
628
629  if (!T->isStructureType()) {
630    return 0;
631  }
632
633  clang::RecordDecl *RD = T->getAsStructureType()->getDecl();
634  RD = RD->getDefinition();
635  for (clang::RecordDecl::field_iterator FI = RD->field_begin(),
636         FE = RD->field_end();
637       FI != FE;
638       FI++) {
639    const clang::FieldDecl *FD = *FI;
640    const clang::Type *FT = RSExportType::GetTypeOfDecl(FD);
641    if (CountRSObjectTypes(C, FT, Loc)) {
642      // Sub-structs should only count once (as should arrays, etc.)
643      RSObjectCount++;
644    }
645  }
646
647  return RSObjectCount;
648}
649
650static clang::Stmt *ClearStructRSObject(
651    clang::ASTContext &C,
652    clang::DeclContext *DC,
653    clang::Expr *RefRSStruct,
654    clang::SourceLocation StartLoc,
655    clang::SourceLocation Loc) {
656  const clang::Type *BaseType = RefRSStruct->getType().getTypePtr();
657
658  slangAssert(!BaseType->isArrayType());
659
660  // Structs should show up as unknown primitive types
661  slangAssert(RSExportPrimitiveType::GetRSSpecificType(BaseType) ==
662              DataTypeUnknown);
663
664  unsigned FieldsToDestroy = CountRSObjectTypes(C, BaseType, Loc);
665  slangAssert(FieldsToDestroy != 0);
666
667  unsigned StmtCount = 0;
668  clang::Stmt **StmtArray = new clang::Stmt*[FieldsToDestroy];
669  for (unsigned i = 0; i < FieldsToDestroy; i++) {
670    StmtArray[i] = NULL;
671  }
672
673  // Populate StmtArray by creating a destructor for each RS object field
674  clang::RecordDecl *RD = BaseType->getAsStructureType()->getDecl();
675  RD = RD->getDefinition();
676  for (clang::RecordDecl::field_iterator FI = RD->field_begin(),
677         FE = RD->field_end();
678       FI != FE;
679       FI++) {
680    // We just look through all field declarations to see if we find a
681    // declaration for an RS object type (or an array of one).
682    bool IsArrayType = false;
683    clang::FieldDecl *FD = *FI;
684    const clang::Type *FT = RSExportType::GetTypeOfDecl(FD);
685    const clang::Type *OrigType = FT;
686    while (FT && FT->isArrayType()) {
687      FT = FT->getArrayElementTypeNoTypeQual();
688      IsArrayType = true;
689    }
690
691    if (RSExportPrimitiveType::IsRSObjectType(FT)) {
692      clang::DeclAccessPair FoundDecl =
693          clang::DeclAccessPair::make(FD, clang::AS_none);
694      clang::MemberExpr *RSObjectMember =
695          clang::MemberExpr::Create(C,
696                                    RefRSStruct,
697                                    false,
698                                    clang::NestedNameSpecifierLoc(),
699                                    clang::SourceLocation(),
700                                    FD,
701                                    FoundDecl,
702                                    clang::DeclarationNameInfo(),
703                                    NULL,
704                                    OrigType->getCanonicalTypeInternal(),
705                                    clang::VK_RValue,
706                                    clang::OK_Ordinary);
707
708      slangAssert(StmtCount < FieldsToDestroy);
709
710      if (IsArrayType) {
711        StmtArray[StmtCount++] = ClearArrayRSObject(C,
712                                                    DC,
713                                                    RSObjectMember,
714                                                    StartLoc,
715                                                    Loc);
716      } else {
717        StmtArray[StmtCount++] = ClearSingleRSObject(C,
718                                                     RSObjectMember,
719                                                     Loc);
720      }
721    } else if (FT->isStructureType() && CountRSObjectTypes(C, FT, Loc)) {
722      // In this case, we have a nested struct. We may not end up filling all
723      // of the spaces in StmtArray (sub-structs should handle themselves
724      // with separate compound statements).
725      clang::DeclAccessPair FoundDecl =
726          clang::DeclAccessPair::make(FD, clang::AS_none);
727      clang::MemberExpr *RSObjectMember =
728          clang::MemberExpr::Create(C,
729                                    RefRSStruct,
730                                    false,
731                                    clang::NestedNameSpecifierLoc(),
732                                    clang::SourceLocation(),
733                                    FD,
734                                    FoundDecl,
735                                    clang::DeclarationNameInfo(),
736                                    NULL,
737                                    OrigType->getCanonicalTypeInternal(),
738                                    clang::VK_RValue,
739                                    clang::OK_Ordinary);
740
741      if (IsArrayType) {
742        StmtArray[StmtCount++] = ClearArrayRSObject(C,
743                                                    DC,
744                                                    RSObjectMember,
745                                                    StartLoc,
746                                                    Loc);
747      } else {
748        StmtArray[StmtCount++] = ClearStructRSObject(C,
749                                                     DC,
750                                                     RSObjectMember,
751                                                     StartLoc,
752                                                     Loc);
753      }
754    }
755  }
756
757  slangAssert(StmtCount > 0);
758  clang::CompoundStmt *CS = new(C) clang::CompoundStmt(
759      C, llvm::makeArrayRef(StmtArray, StmtCount), Loc, Loc);
760
761  delete [] StmtArray;
762
763  return CS;
764}
765
766static clang::Stmt *CreateSingleRSSetObject(clang::ASTContext &C,
767                                            clang::Expr *DstExpr,
768                                            clang::Expr *SrcExpr,
769                                            clang::SourceLocation StartLoc,
770                                            clang::SourceLocation Loc) {
771  const clang::Type *T = DstExpr->getType().getTypePtr();
772  clang::FunctionDecl *SetObjectFD = RSObjectRefCount::GetRSSetObjectFD(T);
773  slangAssert((SetObjectFD != NULL) &&
774              "rsSetObject doesn't cover all RS object types");
775
776  clang::QualType SetObjectFDType = SetObjectFD->getType();
777  clang::QualType SetObjectFDArgType[2];
778  SetObjectFDArgType[0] = SetObjectFD->getParamDecl(0)->getOriginalType();
779  SetObjectFDArgType[1] = SetObjectFD->getParamDecl(1)->getOriginalType();
780
781  clang::Expr *RefRSSetObjectFD =
782      clang::DeclRefExpr::Create(C,
783                                 clang::NestedNameSpecifierLoc(),
784                                 clang::SourceLocation(),
785                                 SetObjectFD,
786                                 false,
787                                 Loc,
788                                 SetObjectFDType,
789                                 clang::VK_RValue,
790                                 NULL);
791
792  clang::Expr *RSSetObjectFP =
793      clang::ImplicitCastExpr::Create(C,
794                                      C.getPointerType(SetObjectFDType),
795                                      clang::CK_FunctionToPointerDecay,
796                                      RefRSSetObjectFD,
797                                      NULL,
798                                      clang::VK_RValue);
799
800  llvm::SmallVector<clang::Expr*, 2> ArgList;
801  ArgList.push_back(new(C) clang::UnaryOperator(DstExpr,
802                                                clang::UO_AddrOf,
803                                                SetObjectFDArgType[0],
804                                                clang::VK_RValue,
805                                                clang::OK_Ordinary,
806                                                Loc));
807  ArgList.push_back(SrcExpr);
808
809  clang::CallExpr *RSSetObjectCall =
810      new(C) clang::CallExpr(C,
811                             RSSetObjectFP,
812                             ArgList,
813                             SetObjectFD->getCallResultType(),
814                             clang::VK_RValue,
815                             Loc);
816
817  return RSSetObjectCall;
818}
819
820static clang::Stmt *CreateStructRSSetObject(clang::ASTContext &C,
821                                            clang::Expr *LHS,
822                                            clang::Expr *RHS,
823                                            clang::SourceLocation StartLoc,
824                                            clang::SourceLocation Loc);
825
826/*static clang::Stmt *CreateArrayRSSetObject(clang::ASTContext &C,
827                                           clang::Expr *DstArr,
828                                           clang::Expr *SrcArr,
829                                           clang::SourceLocation StartLoc,
830                                           clang::SourceLocation Loc) {
831  clang::DeclContext *DC = NULL;
832  const clang::Type *BaseType = DstArr->getType().getTypePtr();
833  slangAssert(BaseType->isArrayType());
834
835  int NumArrayElements = ArrayDim(BaseType);
836  // Actually extract out the base RS object type for use later
837  BaseType = BaseType->getArrayElementTypeNoTypeQual();
838
839  clang::Stmt *StmtArray[2] = {NULL};
840  int StmtCtr = 0;
841
842  if (NumArrayElements <= 0) {
843    return NULL;
844  }
845
846  // Create helper variable for iterating through elements
847  clang::IdentifierInfo& II = C.Idents.get("rsIntIter");
848  clang::VarDecl *IIVD =
849      clang::VarDecl::Create(C,
850                             DC,
851                             StartLoc,
852                             Loc,
853                             &II,
854                             C.IntTy,
855                             C.getTrivialTypeSourceInfo(C.IntTy),
856                             clang::SC_None,
857                             clang::SC_None);
858  clang::Decl *IID = (clang::Decl *)IIVD;
859
860  clang::DeclGroupRef DGR = clang::DeclGroupRef::Create(C, &IID, 1);
861  StmtArray[StmtCtr++] = new(C) clang::DeclStmt(DGR, Loc, Loc);
862
863  // Form the actual loop
864  // for (Init; Cond; Inc)
865  //   RSSetObjectCall;
866
867  // Init -> "rsIntIter = 0"
868  clang::DeclRefExpr *RefrsIntIter =
869      clang::DeclRefExpr::Create(C,
870                                 clang::NestedNameSpecifierLoc(),
871                                 IIVD,
872                                 Loc,
873                                 C.IntTy,
874                                 clang::VK_RValue,
875                                 NULL);
876
877  clang::Expr *Int0 = clang::IntegerLiteral::Create(C,
878      llvm::APInt(C.getTypeSize(C.IntTy), 0), C.IntTy, Loc);
879
880  clang::BinaryOperator *Init =
881      new(C) clang::BinaryOperator(RefrsIntIter,
882                                   Int0,
883                                   clang::BO_Assign,
884                                   C.IntTy,
885                                   clang::VK_RValue,
886                                   clang::OK_Ordinary,
887                                   Loc);
888
889  // Cond -> "rsIntIter < NumArrayElements"
890  clang::Expr *NumArrayElementsExpr = clang::IntegerLiteral::Create(C,
891      llvm::APInt(C.getTypeSize(C.IntTy), NumArrayElements), C.IntTy, Loc);
892
893  clang::BinaryOperator *Cond =
894      new(C) clang::BinaryOperator(RefrsIntIter,
895                                   NumArrayElementsExpr,
896                                   clang::BO_LT,
897                                   C.IntTy,
898                                   clang::VK_RValue,
899                                   clang::OK_Ordinary,
900                                   Loc);
901
902  // Inc -> "rsIntIter++"
903  clang::UnaryOperator *Inc =
904      new(C) clang::UnaryOperator(RefrsIntIter,
905                                  clang::UO_PostInc,
906                                  C.IntTy,
907                                  clang::VK_RValue,
908                                  clang::OK_Ordinary,
909                                  Loc);
910
911  // Body -> "rsSetObject(&Dst[rsIntIter], Src[rsIntIter]);"
912  // Loop operates on individual array elements
913
914  clang::Expr *DstArrPtr =
915      clang::ImplicitCastExpr::Create(C,
916          C.getPointerType(BaseType->getCanonicalTypeInternal()),
917          clang::CK_ArrayToPointerDecay,
918          DstArr,
919          NULL,
920          clang::VK_RValue);
921
922  clang::Expr *DstArrPtrSubscript =
923      new(C) clang::ArraySubscriptExpr(DstArrPtr,
924                                       RefrsIntIter,
925                                       BaseType->getCanonicalTypeInternal(),
926                                       clang::VK_RValue,
927                                       clang::OK_Ordinary,
928                                       Loc);
929
930  clang::Expr *SrcArrPtr =
931      clang::ImplicitCastExpr::Create(C,
932          C.getPointerType(BaseType->getCanonicalTypeInternal()),
933          clang::CK_ArrayToPointerDecay,
934          SrcArr,
935          NULL,
936          clang::VK_RValue);
937
938  clang::Expr *SrcArrPtrSubscript =
939      new(C) clang::ArraySubscriptExpr(SrcArrPtr,
940                                       RefrsIntIter,
941                                       BaseType->getCanonicalTypeInternal(),
942                                       clang::VK_RValue,
943                                       clang::OK_Ordinary,
944                                       Loc);
945
946  DataType DT = RSExportPrimitiveType::GetRSSpecificType(BaseType);
947
948  clang::Stmt *RSSetObjectCall = NULL;
949  if (BaseType->isArrayType()) {
950    RSSetObjectCall = CreateArrayRSSetObject(C, DstArrPtrSubscript,
951                                             SrcArrPtrSubscript,
952                                             StartLoc, Loc);
953  } else if (DT == DataTypeUnknown) {
954    RSSetObjectCall = CreateStructRSSetObject(C, DstArrPtrSubscript,
955                                              SrcArrPtrSubscript,
956                                              StartLoc, Loc);
957  } else {
958    RSSetObjectCall = CreateSingleRSSetObject(C, DstArrPtrSubscript,
959                                              SrcArrPtrSubscript,
960                                              StartLoc, Loc);
961  }
962
963  clang::ForStmt *DestructorLoop =
964      new(C) clang::ForStmt(C,
965                            Init,
966                            Cond,
967                            NULL,  // no condVar
968                            Inc,
969                            RSSetObjectCall,
970                            Loc,
971                            Loc,
972                            Loc);
973
974  StmtArray[StmtCtr++] = DestructorLoop;
975  slangAssert(StmtCtr == 2);
976
977  clang::CompoundStmt *CS =
978      new(C) clang::CompoundStmt(C, StmtArray, StmtCtr, Loc, Loc);
979
980  return CS;
981} */
982
983static clang::Stmt *CreateStructRSSetObject(clang::ASTContext &C,
984                                            clang::Expr *LHS,
985                                            clang::Expr *RHS,
986                                            clang::SourceLocation StartLoc,
987                                            clang::SourceLocation Loc) {
988  clang::QualType QT = LHS->getType();
989  const clang::Type *T = QT.getTypePtr();
990  slangAssert(T->isStructureType());
991  slangAssert(!RSExportPrimitiveType::IsRSObjectType(T));
992
993  // Keep an extra slot for the original copy (memcpy)
994  unsigned FieldsToSet = CountRSObjectTypes(C, T, Loc) + 1;
995
996  unsigned StmtCount = 0;
997  clang::Stmt **StmtArray = new clang::Stmt*[FieldsToSet];
998  for (unsigned i = 0; i < FieldsToSet; i++) {
999    StmtArray[i] = NULL;
1000  }
1001
1002  clang::RecordDecl *RD = T->getAsStructureType()->getDecl();
1003  RD = RD->getDefinition();
1004  for (clang::RecordDecl::field_iterator FI = RD->field_begin(),
1005         FE = RD->field_end();
1006       FI != FE;
1007       FI++) {
1008    bool IsArrayType = false;
1009    clang::FieldDecl *FD = *FI;
1010    const clang::Type *FT = RSExportType::GetTypeOfDecl(FD);
1011    const clang::Type *OrigType = FT;
1012
1013    if (!CountRSObjectTypes(C, FT, Loc)) {
1014      // Skip to next if we don't have any viable RS object types
1015      continue;
1016    }
1017
1018    clang::DeclAccessPair FoundDecl =
1019        clang::DeclAccessPair::make(FD, clang::AS_none);
1020    clang::MemberExpr *DstMember =
1021        clang::MemberExpr::Create(C,
1022                                  LHS,
1023                                  false,
1024                                  clang::NestedNameSpecifierLoc(),
1025                                  clang::SourceLocation(),
1026                                  FD,
1027                                  FoundDecl,
1028                                  clang::DeclarationNameInfo(),
1029                                  NULL,
1030                                  OrigType->getCanonicalTypeInternal(),
1031                                  clang::VK_RValue,
1032                                  clang::OK_Ordinary);
1033
1034    clang::MemberExpr *SrcMember =
1035        clang::MemberExpr::Create(C,
1036                                  RHS,
1037                                  false,
1038                                  clang::NestedNameSpecifierLoc(),
1039                                  clang::SourceLocation(),
1040                                  FD,
1041                                  FoundDecl,
1042                                  clang::DeclarationNameInfo(),
1043                                  NULL,
1044                                  OrigType->getCanonicalTypeInternal(),
1045                                  clang::VK_RValue,
1046                                  clang::OK_Ordinary);
1047
1048    if (FT->isArrayType()) {
1049      FT = FT->getArrayElementTypeNoTypeQual();
1050      IsArrayType = true;
1051    }
1052
1053    DataType DT = RSExportPrimitiveType::GetRSSpecificType(FT);
1054
1055    if (IsArrayType) {
1056      clang::DiagnosticsEngine &DiagEngine = C.getDiagnostics();
1057      DiagEngine.Report(
1058        clang::FullSourceLoc(Loc, C.getSourceManager()),
1059        DiagEngine.getCustomDiagID(
1060          clang::DiagnosticsEngine::Error,
1061          "Arrays of RS object types within structures cannot be copied"));
1062      // TODO(srhines): Support setting arrays of RS objects
1063      // StmtArray[StmtCount++] =
1064      //    CreateArrayRSSetObject(C, DstMember, SrcMember, StartLoc, Loc);
1065    } else if (DT == DataTypeUnknown) {
1066      StmtArray[StmtCount++] =
1067          CreateStructRSSetObject(C, DstMember, SrcMember, StartLoc, Loc);
1068    } else if (RSExportPrimitiveType::IsRSObjectType(DT)) {
1069      StmtArray[StmtCount++] =
1070          CreateSingleRSSetObject(C, DstMember, SrcMember, StartLoc, Loc);
1071    } else {
1072      slangAssert(false);
1073    }
1074  }
1075
1076  slangAssert(StmtCount < FieldsToSet);
1077
1078  // We still need to actually do the overall struct copy. For simplicity,
1079  // we just do a straight-up assignment (which will still preserve all
1080  // the proper RS object reference counts).
1081  clang::BinaryOperator *CopyStruct =
1082      new(C) clang::BinaryOperator(LHS, RHS, clang::BO_Assign, QT,
1083                                   clang::VK_RValue, clang::OK_Ordinary, Loc,
1084                                   false);
1085  StmtArray[StmtCount++] = CopyStruct;
1086
1087  clang::CompoundStmt *CS = new(C) clang::CompoundStmt(
1088      C, llvm::makeArrayRef(StmtArray, StmtCount), Loc, Loc);
1089
1090  delete [] StmtArray;
1091
1092  return CS;
1093}
1094
1095}  // namespace
1096
1097void RSObjectRefCount::Scope::ReplaceRSObjectAssignment(
1098    clang::BinaryOperator *AS) {
1099
1100  clang::QualType QT = AS->getType();
1101
1102  clang::ASTContext &C = RSObjectRefCount::GetRSSetObjectFD(
1103      DataTypeRSAllocation)->getASTContext();
1104
1105  clang::SourceLocation Loc = AS->getExprLoc();
1106  clang::SourceLocation StartLoc = AS->getLHS()->getExprLoc();
1107  clang::Stmt *UpdatedStmt = NULL;
1108
1109  if (!RSExportPrimitiveType::IsRSObjectType(QT.getTypePtr())) {
1110    // By definition, this is a struct assignment if we get here
1111    UpdatedStmt =
1112        CreateStructRSSetObject(C, AS->getLHS(), AS->getRHS(), StartLoc, Loc);
1113  } else {
1114    UpdatedStmt =
1115        CreateSingleRSSetObject(C, AS->getLHS(), AS->getRHS(), StartLoc, Loc);
1116  }
1117
1118  RSASTReplace R(C);
1119  R.ReplaceStmt(mCS, AS, UpdatedStmt);
1120}
1121
1122void RSObjectRefCount::Scope::AppendRSObjectInit(
1123    clang::VarDecl *VD,
1124    clang::DeclStmt *DS,
1125    DataType DT,
1126    clang::Expr *InitExpr) {
1127  slangAssert(VD);
1128
1129  if (!InitExpr) {
1130    return;
1131  }
1132
1133  clang::ASTContext &C = RSObjectRefCount::GetRSSetObjectFD(
1134      DataTypeRSAllocation)->getASTContext();
1135  clang::SourceLocation Loc = RSObjectRefCount::GetRSSetObjectFD(
1136      DataTypeRSAllocation)->getLocation();
1137  clang::SourceLocation StartLoc = RSObjectRefCount::GetRSSetObjectFD(
1138      DataTypeRSAllocation)->getInnerLocStart();
1139
1140  if (DT == DataTypeIsStruct) {
1141    const clang::Type *T = RSExportType::GetTypeOfDecl(VD);
1142    clang::DeclRefExpr *RefRSVar =
1143        clang::DeclRefExpr::Create(C,
1144                                   clang::NestedNameSpecifierLoc(),
1145                                   clang::SourceLocation(),
1146                                   VD,
1147                                   false,
1148                                   Loc,
1149                                   T->getCanonicalTypeInternal(),
1150                                   clang::VK_RValue,
1151                                   NULL);
1152
1153    clang::Stmt *RSSetObjectOps =
1154        CreateStructRSSetObject(C, RefRSVar, InitExpr, StartLoc, Loc);
1155
1156    std::list<clang::Stmt*> StmtList;
1157    StmtList.push_back(RSSetObjectOps);
1158    AppendAfterStmt(C, mCS, DS, StmtList);
1159    return;
1160  }
1161
1162  clang::FunctionDecl *SetObjectFD = RSObjectRefCount::GetRSSetObjectFD(DT);
1163  slangAssert((SetObjectFD != NULL) &&
1164              "rsSetObject doesn't cover all RS object types");
1165
1166  clang::QualType SetObjectFDType = SetObjectFD->getType();
1167  clang::QualType SetObjectFDArgType[2];
1168  SetObjectFDArgType[0] = SetObjectFD->getParamDecl(0)->getOriginalType();
1169  SetObjectFDArgType[1] = SetObjectFD->getParamDecl(1)->getOriginalType();
1170
1171  clang::Expr *RefRSSetObjectFD =
1172      clang::DeclRefExpr::Create(C,
1173                                 clang::NestedNameSpecifierLoc(),
1174                                 clang::SourceLocation(),
1175                                 SetObjectFD,
1176                                 false,
1177                                 Loc,
1178                                 SetObjectFDType,
1179                                 clang::VK_RValue,
1180                                 NULL);
1181
1182  clang::Expr *RSSetObjectFP =
1183      clang::ImplicitCastExpr::Create(C,
1184                                      C.getPointerType(SetObjectFDType),
1185                                      clang::CK_FunctionToPointerDecay,
1186                                      RefRSSetObjectFD,
1187                                      NULL,
1188                                      clang::VK_RValue);
1189
1190  const clang::Type *T = RSExportType::GetTypeOfDecl(VD);
1191  clang::DeclRefExpr *RefRSVar =
1192      clang::DeclRefExpr::Create(C,
1193                                 clang::NestedNameSpecifierLoc(),
1194                                 clang::SourceLocation(),
1195                                 VD,
1196                                 false,
1197                                 Loc,
1198                                 T->getCanonicalTypeInternal(),
1199                                 clang::VK_RValue,
1200                                 NULL);
1201
1202  llvm::SmallVector<clang::Expr*, 2> ArgList;
1203  ArgList.push_back(new(C) clang::UnaryOperator(RefRSVar,
1204                                                clang::UO_AddrOf,
1205                                                SetObjectFDArgType[0],
1206                                                clang::VK_RValue,
1207                                                clang::OK_Ordinary,
1208                                                Loc));
1209  ArgList.push_back(InitExpr);
1210
1211  clang::CallExpr *RSSetObjectCall =
1212      new(C) clang::CallExpr(C,
1213                             RSSetObjectFP,
1214                             ArgList,
1215                             SetObjectFD->getCallResultType(),
1216                             clang::VK_RValue,
1217                             Loc);
1218
1219  std::list<clang::Stmt*> StmtList;
1220  StmtList.push_back(RSSetObjectCall);
1221  AppendAfterStmt(C, mCS, DS, StmtList);
1222}
1223
1224void RSObjectRefCount::Scope::InsertLocalVarDestructors() {
1225  for (std::list<clang::VarDecl*>::const_iterator I = mRSO.begin(),
1226          E = mRSO.end();
1227        I != E;
1228        I++) {
1229    clang::VarDecl *VD = *I;
1230    clang::Stmt *RSClearObjectCall = ClearRSObject(VD, VD->getDeclContext());
1231    if (RSClearObjectCall) {
1232      DestructorVisitor DV((*mRSO.begin())->getASTContext(),
1233                           mCS,
1234                           RSClearObjectCall,
1235                           VD->getSourceRange().getBegin());
1236      DV.Visit(mCS);
1237      DV.InsertDestructors();
1238    }
1239  }
1240}
1241
1242clang::Stmt *RSObjectRefCount::Scope::ClearRSObject(
1243    clang::VarDecl *VD,
1244    clang::DeclContext *DC) {
1245  slangAssert(VD);
1246  clang::ASTContext &C = VD->getASTContext();
1247  clang::SourceLocation Loc = VD->getLocation();
1248  clang::SourceLocation StartLoc = VD->getInnerLocStart();
1249  const clang::Type *T = RSExportType::GetTypeOfDecl(VD);
1250
1251  // Reference expr to target RS object variable
1252  clang::DeclRefExpr *RefRSVar =
1253      clang::DeclRefExpr::Create(C,
1254                                 clang::NestedNameSpecifierLoc(),
1255                                 clang::SourceLocation(),
1256                                 VD,
1257                                 false,
1258                                 Loc,
1259                                 T->getCanonicalTypeInternal(),
1260                                 clang::VK_RValue,
1261                                 NULL);
1262
1263  if (T->isArrayType()) {
1264    return ClearArrayRSObject(C, DC, RefRSVar, StartLoc, Loc);
1265  }
1266
1267  DataType DT = RSExportPrimitiveType::GetRSSpecificType(T);
1268
1269  if (DT == DataTypeUnknown ||
1270      DT == DataTypeIsStruct) {
1271    return ClearStructRSObject(C, DC, RefRSVar, StartLoc, Loc);
1272  }
1273
1274  slangAssert((RSExportPrimitiveType::IsRSObjectType(DT)) &&
1275              "Should be RS object");
1276
1277  return ClearSingleRSObject(C, RefRSVar, Loc);
1278}
1279
1280bool RSObjectRefCount::InitializeRSObject(clang::VarDecl *VD,
1281                                          DataType *DT,
1282                                          clang::Expr **InitExpr) {
1283  slangAssert(VD && DT && InitExpr);
1284  const clang::Type *T = RSExportType::GetTypeOfDecl(VD);
1285
1286  // Loop through array types to get to base type
1287  while (T && T->isArrayType()) {
1288    T = T->getArrayElementTypeNoTypeQual();
1289  }
1290
1291  bool DataTypeIsStructWithRSObject = false;
1292  *DT = RSExportPrimitiveType::GetRSSpecificType(T);
1293
1294  if (*DT == DataTypeUnknown) {
1295    if (RSExportPrimitiveType::IsStructureTypeWithRSObject(T)) {
1296      *DT = DataTypeIsStruct;
1297      DataTypeIsStructWithRSObject = true;
1298    } else {
1299      return false;
1300    }
1301  }
1302
1303  bool DataTypeIsRSObject = false;
1304  if (DataTypeIsStructWithRSObject) {
1305    DataTypeIsRSObject = true;
1306  } else {
1307    DataTypeIsRSObject = RSExportPrimitiveType::IsRSObjectType(*DT);
1308  }
1309  *InitExpr = VD->getInit();
1310
1311  if (!DataTypeIsRSObject && *InitExpr) {
1312    // If we already have an initializer for a matrix type, we are done.
1313    return DataTypeIsRSObject;
1314  }
1315
1316  clang::Expr *ZeroInitializer =
1317      CreateZeroInitializerForRSSpecificType(*DT,
1318                                             VD->getASTContext(),
1319                                             VD->getLocation());
1320
1321  if (ZeroInitializer) {
1322    ZeroInitializer->setType(T->getCanonicalTypeInternal());
1323    VD->setInit(ZeroInitializer);
1324  }
1325
1326  return DataTypeIsRSObject;
1327}
1328
1329clang::Expr *RSObjectRefCount::CreateZeroInitializerForRSSpecificType(
1330    DataType DT,
1331    clang::ASTContext &C,
1332    const clang::SourceLocation &Loc) {
1333  clang::Expr *Res = NULL;
1334  switch (DT) {
1335    case DataTypeIsStruct:
1336    case DataTypeRSElement:
1337    case DataTypeRSType:
1338    case DataTypeRSAllocation:
1339    case DataTypeRSSampler:
1340    case DataTypeRSScript:
1341    case DataTypeRSMesh:
1342    case DataTypeRSPath:
1343    case DataTypeRSProgramFragment:
1344    case DataTypeRSProgramVertex:
1345    case DataTypeRSProgramRaster:
1346    case DataTypeRSProgramStore:
1347    case DataTypeRSFont: {
1348      //    (ImplicitCastExpr 'nullptr_t'
1349      //      (IntegerLiteral 0)))
1350      llvm::APInt Zero(C.getTypeSize(C.IntTy), 0);
1351      clang::Expr *Int0 = clang::IntegerLiteral::Create(C, Zero, C.IntTy, Loc);
1352      clang::Expr *CastToNull =
1353          clang::ImplicitCastExpr::Create(C,
1354                                          C.NullPtrTy,
1355                                          clang::CK_IntegralToPointer,
1356                                          Int0,
1357                                          NULL,
1358                                          clang::VK_RValue);
1359
1360      llvm::SmallVector<clang::Expr*, 1>InitList;
1361      InitList.push_back(CastToNull);
1362
1363      Res = new(C) clang::InitListExpr(C, Loc, InitList, Loc);
1364      break;
1365    }
1366    case DataTypeRSMatrix2x2:
1367    case DataTypeRSMatrix3x3:
1368    case DataTypeRSMatrix4x4: {
1369      // RS matrix is not completely an RS object. They hold data by themselves.
1370      // (InitListExpr rs_matrix2x2
1371      //   (InitListExpr float[4]
1372      //     (FloatingLiteral 0)
1373      //     (FloatingLiteral 0)
1374      //     (FloatingLiteral 0)
1375      //     (FloatingLiteral 0)))
1376      clang::QualType FloatTy = C.FloatTy;
1377      // Constructor sets value to 0.0f by default
1378      llvm::APFloat Val(C.getFloatTypeSemantics(FloatTy));
1379      clang::FloatingLiteral *Float0Val =
1380          clang::FloatingLiteral::Create(C,
1381                                         Val,
1382                                         /* isExact = */true,
1383                                         FloatTy,
1384                                         Loc);
1385
1386      unsigned N = 0;
1387      if (DT == DataTypeRSMatrix2x2)
1388        N = 2;
1389      else if (DT == DataTypeRSMatrix3x3)
1390        N = 3;
1391      else if (DT == DataTypeRSMatrix4x4)
1392        N = 4;
1393      unsigned N_2 = N * N;
1394
1395      // Assume we are going to be allocating 16 elements, since 4x4 is max.
1396      llvm::SmallVector<clang::Expr*, 16> InitVals;
1397      for (unsigned i = 0; i < N_2; i++)
1398        InitVals.push_back(Float0Val);
1399      clang::Expr *InitExpr =
1400          new(C) clang::InitListExpr(C, Loc, InitVals, Loc);
1401      InitExpr->setType(C.getConstantArrayType(FloatTy,
1402                                               llvm::APInt(32, N_2),
1403                                               clang::ArrayType::Normal,
1404                                               /* EltTypeQuals = */0));
1405      llvm::SmallVector<clang::Expr*, 1> InitExprVec;
1406      InitExprVec.push_back(InitExpr);
1407
1408      Res = new(C) clang::InitListExpr(C, Loc, InitExprVec, Loc);
1409      break;
1410    }
1411    case DataTypeUnknown:
1412    case DataTypeFloat16:
1413    case DataTypeFloat32:
1414    case DataTypeFloat64:
1415    case DataTypeSigned8:
1416    case DataTypeSigned16:
1417    case DataTypeSigned32:
1418    case DataTypeSigned64:
1419    case DataTypeUnsigned8:
1420    case DataTypeUnsigned16:
1421    case DataTypeUnsigned32:
1422    case DataTypeUnsigned64:
1423    case DataTypeBoolean:
1424    case DataTypeUnsigned565:
1425    case DataTypeUnsigned5551:
1426    case DataTypeUnsigned4444:
1427    case DataTypeMax: {
1428      slangAssert(false && "Not RS object type!");
1429    }
1430    // No default case will enable compiler detecting the missing cases
1431  }
1432
1433  return Res;
1434}
1435
1436void RSObjectRefCount::VisitDeclStmt(clang::DeclStmt *DS) {
1437  for (clang::DeclStmt::decl_iterator I = DS->decl_begin(), E = DS->decl_end();
1438       I != E;
1439       I++) {
1440    clang::Decl *D = *I;
1441    if (D->getKind() == clang::Decl::Var) {
1442      clang::VarDecl *VD = static_cast<clang::VarDecl*>(D);
1443      DataType DT = DataTypeUnknown;
1444      clang::Expr *InitExpr = NULL;
1445      if (InitializeRSObject(VD, &DT, &InitExpr)) {
1446        // We need to zero-init all RS object types (including matrices), ...
1447        getCurrentScope()->AppendRSObjectInit(VD, DS, DT, InitExpr);
1448        // ... but, only add to the list of RS objects if we have some
1449        // non-matrix RS object fields.
1450        if (CountRSObjectTypes(mCtx, VD->getType().getTypePtr(),
1451                               VD->getLocation())) {
1452          getCurrentScope()->addRSObject(VD);
1453        }
1454      }
1455    }
1456  }
1457}
1458
1459void RSObjectRefCount::VisitCompoundStmt(clang::CompoundStmt *CS) {
1460  if (!CS->body_empty()) {
1461    // Push a new scope
1462    Scope *S = new Scope(CS);
1463    mScopeStack.push(S);
1464
1465    VisitStmt(CS);
1466
1467    // Destroy the scope
1468    slangAssert((getCurrentScope() == S) && "Corrupted scope stack!");
1469    S->InsertLocalVarDestructors();
1470    mScopeStack.pop();
1471    delete S;
1472  }
1473}
1474
1475void RSObjectRefCount::VisitBinAssign(clang::BinaryOperator *AS) {
1476  clang::QualType QT = AS->getType();
1477
1478  if (CountRSObjectTypes(mCtx, QT.getTypePtr(), AS->getExprLoc())) {
1479    getCurrentScope()->ReplaceRSObjectAssignment(AS);
1480  }
1481}
1482
1483void RSObjectRefCount::VisitStmt(clang::Stmt *S) {
1484  for (clang::Stmt::child_iterator I = S->child_begin(), E = S->child_end();
1485       I != E;
1486       I++) {
1487    if (clang::Stmt *Child = *I) {
1488      Visit(Child);
1489    }
1490  }
1491}
1492
1493// This function walks the list of global variables and (potentially) creates
1494// a single global static destructor function that properly decrements
1495// reference counts on the contained RS object types.
1496clang::FunctionDecl *RSObjectRefCount::CreateStaticGlobalDtor() {
1497  Init();
1498
1499  clang::DeclContext *DC = mCtx.getTranslationUnitDecl();
1500  clang::SourceLocation loc;
1501
1502  llvm::StringRef SR(".rs.dtor");
1503  clang::IdentifierInfo &II = mCtx.Idents.get(SR);
1504  clang::DeclarationName N(&II);
1505  clang::FunctionProtoType::ExtProtoInfo EPI;
1506  clang::QualType T = mCtx.getFunctionType(mCtx.VoidTy,
1507      llvm::ArrayRef<clang::QualType>(), EPI);
1508  clang::FunctionDecl *FD = NULL;
1509
1510  // Generate rsClearObject() call chains for every global variable
1511  // (whether static or extern).
1512  std::list<clang::Stmt *> StmtList;
1513  for (clang::DeclContext::decl_iterator I = DC->decls_begin(),
1514          E = DC->decls_end(); I != E; I++) {
1515    clang::VarDecl *VD = llvm::dyn_cast<clang::VarDecl>(*I);
1516    if (VD) {
1517      if (CountRSObjectTypes(mCtx, VD->getType().getTypePtr(), loc)) {
1518        if (!FD) {
1519          // Only create FD if we are going to use it.
1520          FD = clang::FunctionDecl::Create(mCtx, DC, loc, loc, N, T, NULL,
1521                                           clang::SC_None);
1522        }
1523        // Make sure to create any helpers within the function's DeclContext,
1524        // not the one associated with the global translation unit.
1525        clang::Stmt *RSClearObjectCall = Scope::ClearRSObject(VD, FD);
1526        StmtList.push_back(RSClearObjectCall);
1527      }
1528    }
1529  }
1530
1531  // Nothing needs to be destroyed, so don't emit a dtor.
1532  if (StmtList.empty()) {
1533    return NULL;
1534  }
1535
1536  clang::CompoundStmt *CS = BuildCompoundStmt(mCtx, StmtList, loc);
1537
1538  FD->setBody(CS);
1539
1540  return FD;
1541}
1542
1543}  // namespace slang
1544