slang_rs_check_ast.cpp revision 5abbe0e9ca2508260b627ffef2bf01e2554e8357
1/*
2 * Copyright 2012, 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_check_ast.h"
18
19#include "slang_assert.h"
20#include "slang_rs.h"
21#include "slang_rs_export_foreach.h"
22#include "slang_rs_export_type.h"
23
24namespace slang {
25
26void RSCheckAST::VisitStmt(clang::Stmt *S) {
27  // This function does the actual iteration through all sub-Stmt's within
28  // a given Stmt. Note that this function is skipped by all of the other
29  // Visit* functions if we have already found a higher-level match.
30  for (clang::Stmt::child_iterator I = S->child_begin(), E = S->child_end();
31       I != E;
32       I++) {
33    if (clang::Stmt *Child = *I) {
34      Visit(Child);
35    }
36  }
37}
38
39void RSCheckAST::WarnOnSetElementAt(clang::CallExpr *E) {
40  clang::FunctionDecl *Decl;
41  Decl = clang::dyn_cast_or_null<clang::FunctionDecl>(E->getCalleeDecl());
42
43  if (!Decl || Decl->getNameAsString() != std::string("rsSetElementAt")) {
44    return;
45  }
46
47  clang::Expr *Expr;
48  clang::ImplicitCastExpr *ImplCast;
49  Expr = E->getArg(1);
50  ImplCast = clang::dyn_cast_or_null<clang::ImplicitCastExpr>(Expr);
51
52  if (!ImplCast) {
53    return;
54  }
55
56  const clang::Type *Ty;
57  const clang::VectorType *VectorTy;
58  const clang::BuiltinType *ElementTy;
59  Ty = ImplCast->getSubExpr()->getType()->getPointeeType()
60    ->getUnqualifiedDesugaredType();
61  VectorTy = clang::dyn_cast_or_null<clang::VectorType>(Ty);
62
63  if (VectorTy) {
64    ElementTy = clang::dyn_cast_or_null<clang::BuiltinType>(
65      VectorTy->getElementType()->getUnqualifiedDesugaredType());
66  } else {
67    ElementTy = clang::dyn_cast_or_null<clang::BuiltinType>(
68      Ty->getUnqualifiedDesugaredType());
69  }
70
71  if (!ElementTy) {
72    return;
73  }
74
75  // We only support vectors with 2, 3 or 4 elements.
76  if (VectorTy) {
77    switch (VectorTy->getNumElements()) {
78    default:
79      return;
80    case 2:
81    case 3:
82    case 4:
83      break;
84    }
85  }
86
87  const char *Name;
88
89  switch (ElementTy->getKind()) {
90    case clang::BuiltinType::Float:
91      Name = "float";
92      break;
93    case clang::BuiltinType::Double:
94      Name = "double";
95      break;
96    case clang::BuiltinType::Char_S:
97      Name = "char";
98      break;
99    case clang::BuiltinType::Short:
100      Name = "short";
101      break;
102    case clang::BuiltinType::Int:
103      Name = "int";
104      break;
105    case clang::BuiltinType::Long:
106      Name = "long";
107      break;
108    case clang::BuiltinType::UChar:
109      Name = "uchar";
110      break;
111    case clang::BuiltinType::UShort:
112      Name = "ushort";
113      break;
114    case clang::BuiltinType::UInt:
115      Name = "uint";
116      break;
117    case clang::BuiltinType::ULong:
118      Name = "ulong";
119      break;
120    default:
121      return;
122  }
123
124  clang::DiagnosticBuilder DiagBuilder =
125      Context->ReportWarning(E->getLocStart(),
126                             "untyped rsSetElementAt() can reduce performance. "
127                             "Use rsSetElementAt_%0%1() instead.");
128  DiagBuilder << Name;
129
130  if (VectorTy) {
131    DiagBuilder << VectorTy->getNumElements();
132  } else {
133    DiagBuilder << "";
134  }
135}
136
137void RSCheckAST::VisitCallExpr(clang::CallExpr *E) {
138  WarnOnSetElementAt(E);
139
140  for (clang::CallExpr::arg_iterator AI = E->arg_begin(), AE = E->arg_end();
141       AI != AE; ++AI) {
142    Visit(*AI);
143  }
144}
145
146void RSCheckAST::ValidateFunctionDecl(clang::FunctionDecl *FD) {
147  if (!FD) {
148    return;
149  }
150
151  if (mIsFilterscript) {
152    // Validate parameters for Filterscript.
153    size_t numParams = FD->getNumParams();
154
155    clang::QualType resultType = FD->getReturnType().getCanonicalType();
156
157    // We use FD as our NamedDecl in the case of a bad return type.
158    if (!RSExportType::ValidateType(Context, C, resultType, FD,
159                                    FD->getLocStart(), mTargetAPI,
160                                    mIsFilterscript)) {
161      mValid = false;
162    }
163
164    for (size_t i = 0; i < numParams; i++) {
165      clang::ParmVarDecl *PVD = FD->getParamDecl(i);
166      clang::QualType QT = PVD->getType().getCanonicalType();
167      if (!RSExportType::ValidateType(Context, C, QT, PVD, PVD->getLocStart(),
168                                      mTargetAPI, mIsFilterscript)) {
169        mValid = false;
170      }
171    }
172  }
173
174  bool saveKernel = mInKernel;
175  mInKernel = RSExportForEach::isRSForEachFunc(mTargetAPI, Context, FD);
176
177  if (clang::Stmt *Body = FD->getBody()) {
178    Visit(Body);
179  }
180
181  mInKernel = saveKernel;
182}
183
184
185void RSCheckAST::ValidateVarDecl(clang::VarDecl *VD) {
186  if (!VD) {
187    return;
188  }
189
190  clang::QualType QT = VD->getType();
191
192  if (VD->getFormalLinkage() == clang::ExternalLinkage) {
193    llvm::StringRef TypeName;
194    const clang::Type *T = QT.getTypePtr();
195    if (!RSExportType::NormalizeType(T, TypeName, Context, VD)) {
196      mValid = false;
197    }
198  }
199
200  // We don't allow static (non-const) variables within kernels.
201  if (mInKernel && VD->isStaticLocal()) {
202    if (!QT.isConstQualified()) {
203      Context->ReportError(
204          VD->getLocation(),
205          "Non-const static variables are not allowed in kernels: '%0'")
206          << VD->getName();
207      mValid = false;
208    }
209  }
210
211  if (!RSExportType::ValidateVarDecl(Context, VD, mTargetAPI, mIsFilterscript)) {
212    mValid = false;
213  } else if (clang::Expr *Init = VD->getInit()) {
214    // Only check the initializer if the decl is already ok.
215    Visit(Init);
216  }
217}
218
219
220void RSCheckAST::VisitDeclStmt(clang::DeclStmt *DS) {
221  if (!SlangRS::IsLocInRSHeaderFile(DS->getLocStart(), mSM)) {
222    for (clang::DeclStmt::decl_iterator I = DS->decl_begin(),
223                                        E = DS->decl_end();
224         I != E;
225         ++I) {
226      if (clang::VarDecl *VD = llvm::dyn_cast<clang::VarDecl>(*I)) {
227        ValidateVarDecl(VD);
228      } else if (clang::FunctionDecl *FD =
229            llvm::dyn_cast<clang::FunctionDecl>(*I)) {
230        ValidateFunctionDecl(FD);
231      }
232    }
233  }
234}
235
236
237void RSCheckAST::VisitCastExpr(clang::CastExpr *CE) {
238  if (CE->getCastKind() == clang::CK_BitCast) {
239    clang::QualType QT = CE->getType();
240    const clang::Type *T = QT.getTypePtr();
241    if (T->isVectorType()) {
242      if (llvm::isa<clang::ImplicitCastExpr>(CE)) {
243        Context->ReportError(CE->getExprLoc(), "invalid implicit vector cast");
244      } else {
245        Context->ReportError(CE->getExprLoc(), "invalid vector cast");
246      }
247      mValid = false;
248    }
249  }
250  Visit(CE->getSubExpr());
251}
252
253
254void RSCheckAST::VisitExpr(clang::Expr *E) {
255  // This is where FS checks for code using pointer and/or 64-bit expressions
256  // (i.e. things like casts).
257
258  // First we skip implicit casts (things like function calls and explicit
259  // array accesses rely heavily on them and they are valid.
260  E = E->IgnoreImpCasts();
261  if (mIsFilterscript &&
262      !SlangRS::IsLocInRSHeaderFile(E->getExprLoc(), mSM) &&
263      !RSExportType::ValidateType(Context, C, E->getType(), nullptr, E->getExprLoc(),
264                                  mTargetAPI, mIsFilterscript)) {
265    mValid = false;
266  } else {
267    // Only visit sub-expressions if we haven't already seen a violation.
268    VisitStmt(E);
269  }
270}
271
272
273bool RSCheckAST::Validate() {
274  clang::TranslationUnitDecl *TUDecl = C.getTranslationUnitDecl();
275  for (clang::DeclContext::decl_iterator DI = TUDecl->decls_begin(),
276          DE = TUDecl->decls_end();
277       DI != DE;
278       DI++) {
279    if (!SlangRS::IsLocInRSHeaderFile(DI->getLocStart(), mSM)) {
280      if (clang::VarDecl *VD = llvm::dyn_cast<clang::VarDecl>(*DI)) {
281        ValidateVarDecl(VD);
282      } else if (clang::FunctionDecl *FD =
283            llvm::dyn_cast<clang::FunctionDecl>(*DI)) {
284        ValidateFunctionDecl(FD);
285      } else if (clang::Stmt *Body = (*DI)->getBody()) {
286        Visit(Body);
287      }
288    }
289  }
290
291  return mValid;
292}
293
294}  // namespace slang
295