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_export_func.h"
18
19#include <string>
20
21#include "clang/AST/ASTContext.h"
22#include "clang/AST/Decl.h"
23
24#include "llvm/DerivedTypes.h"
25#include "llvm/Target/TargetData.h"
26
27#include "slang_assert.h"
28#include "slang_rs_context.h"
29
30namespace slang {
31
32namespace {
33
34// Ensure that the exported function is actually valid
35static bool ValidateFuncDecl(clang::DiagnosticsEngine *DiagEngine,
36                             const clang::FunctionDecl *FD) {
37  slangAssert(DiagEngine && FD);
38  const clang::ASTContext &C = FD->getASTContext();
39  if (FD->getResultType().getCanonicalType() != C.VoidTy) {
40    DiagEngine->Report(
41      clang::FullSourceLoc(FD->getLocation(), DiagEngine->getSourceManager()),
42      DiagEngine->getCustomDiagID(clang::DiagnosticsEngine::Error,
43                                  "invokable non-static functions are "
44                                  "required to return void"));
45    return false;
46  }
47  return true;
48}
49
50}  // namespace
51
52RSExportFunc *RSExportFunc::Create(RSContext *Context,
53                                   const clang::FunctionDecl *FD) {
54  llvm::StringRef Name = FD->getName();
55  RSExportFunc *F;
56
57  slangAssert(!Name.empty() && "Function must have a name");
58
59  if (!ValidateFuncDecl(Context->getDiagnostics(), FD)) {
60    return NULL;
61  }
62
63  F = new RSExportFunc(Context, Name, FD);
64
65  // Initialize mParamPacketType
66  if (FD->getNumParams() <= 0) {
67    F->mParamPacketType = NULL;
68  } else {
69    clang::ASTContext &Ctx = Context->getASTContext();
70
71    std::string Id(DUMMY_RS_TYPE_NAME_PREFIX"helper_func_param:");
72    Id.append(F->getName()).append(DUMMY_RS_TYPE_NAME_POSTFIX);
73
74    clang::RecordDecl *RD =
75        clang::RecordDecl::Create(Ctx, clang::TTK_Struct,
76                                  Ctx.getTranslationUnitDecl(),
77                                  clang::SourceLocation(),
78                                  clang::SourceLocation(),
79                                  &Ctx.Idents.get(Id));
80
81    for (unsigned i = 0; i < FD->getNumParams(); i++) {
82      const clang::ParmVarDecl *PVD = FD->getParamDecl(i);
83      llvm::StringRef ParamName = PVD->getName();
84
85      if (PVD->hasDefaultArg())
86        fprintf(stderr, "Note: parameter '%s' in function '%s' has default "
87                        "value which is not supported\n",
88                        ParamName.str().c_str(),
89                        F->getName().c_str());
90
91      clang::FieldDecl *FD =
92          clang::FieldDecl::Create(Ctx,
93                                   RD,
94                                   clang::SourceLocation(),
95                                   clang::SourceLocation(),
96                                   PVD->getIdentifier(),
97                                   PVD->getOriginalType(),
98                                   NULL,
99                                   /* BitWidth = */ NULL,
100                                   /* Mutable = */ false,
101                                   /* HasInit = */ clang::ICIS_NoInit);
102      RD->addDecl(FD);
103    }
104
105    RD->completeDefinition();
106
107    clang::QualType T = Ctx.getTagDeclType(RD);
108    slangAssert(!T.isNull());
109
110    RSExportType *ET =
111      RSExportType::Create(Context, T.getTypePtr());
112
113    if (ET == NULL) {
114      fprintf(stderr, "Failed to export the function %s. There's at least one "
115                      "parameter whose type is not supported by the "
116                      "reflection\n", F->getName().c_str());
117      return NULL;
118    }
119
120    slangAssert((ET->getClass() == RSExportType::ExportClassRecord) &&
121           "Parameter packet must be a record");
122
123    F->mParamPacketType = static_cast<RSExportRecordType *>(ET);
124  }
125
126  return F;
127}
128
129bool
130RSExportFunc::checkParameterPacketType(llvm::StructType *ParamTy) const {
131  if (ParamTy == NULL)
132    return !hasParam();
133  else if (!hasParam())
134    return false;
135
136  slangAssert(mParamPacketType != NULL);
137
138  const RSExportRecordType *ERT = mParamPacketType;
139  // must have same number of elements
140  if (ERT->getFields().size() != ParamTy->getNumElements())
141    return false;
142
143  const llvm::StructLayout *ParamTySL =
144      getRSContext()->getTargetData()->getStructLayout(ParamTy);
145
146  unsigned Index = 0;
147  for (RSExportRecordType::const_field_iterator FI = ERT->fields_begin(),
148       FE = ERT->fields_end(); FI != FE; FI++, Index++) {
149    const RSExportRecordType::Field *F = *FI;
150
151    llvm::Type *T1 = F->getType()->getLLVMType();
152    llvm::Type *T2 = ParamTy->getTypeAtIndex(Index);
153
154    // Fast check
155    if (T1 == T2)
156      continue;
157
158    // Check offset
159    size_t T1Offset = F->getOffsetInParent();
160    size_t T2Offset = ParamTySL->getElementOffset(Index);
161
162    if (T1Offset != T2Offset)
163      return false;
164
165    // Check size
166    size_t T1Size = RSExportType::GetTypeAllocSize(F->getType());
167    size_t T2Size = getRSContext()->getTargetData()->getTypeAllocSize(T2);
168
169    if (T1Size != T2Size)
170      return false;
171  }
172
173  return true;
174}
175
176}  // namespace slang
177