1 /*
2  * Copyright 2011, 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_ast_replace.h"
18 
19 #include "slang_assert.h"
20 
21 #include "llvm/Support/Casting.h"
22 
23 namespace slang {
24 
ReplaceStmt(clang::Stmt * OuterStmt,clang::Stmt * OldStmt,clang::Stmt * NewStmt)25 void RSASTReplace::ReplaceStmt(
26     clang::Stmt *OuterStmt,
27     clang::Stmt *OldStmt,
28     clang::Stmt *NewStmt) {
29   mOldStmt = OldStmt;
30   mNewStmt = NewStmt;
31   mOuterStmt = OuterStmt;
32 
33   // This simplifies use in various Stmt visitor passes where the only
34   // valid type is an Expr.
35   mOldExpr = llvm::dyn_cast<clang::Expr>(OldStmt);
36   if (mOldExpr) {
37     mNewExpr = llvm::dyn_cast<clang::Expr>(NewStmt);
38   }
39   Visit(mOuterStmt);
40 }
41 
ReplaceInCompoundStmt(clang::CompoundStmt * CS)42 void RSASTReplace::ReplaceInCompoundStmt(clang::CompoundStmt *CS) {
43   clang::Stmt **UpdatedStmtList = new clang::Stmt*[CS->size()];
44 
45   unsigned UpdatedStmtCount = 0;
46   clang::CompoundStmt::body_iterator bI = CS->body_begin();
47   clang::CompoundStmt::body_iterator bE = CS->body_end();
48 
49   for ( ; bI != bE; bI++) {
50     if (matchesStmt(*bI)) {
51       UpdatedStmtList[UpdatedStmtCount++] = mNewStmt;
52     } else {
53       UpdatedStmtList[UpdatedStmtCount++] = *bI;
54     }
55   }
56 
57   CS->setStmts(C, UpdatedStmtList, UpdatedStmtCount);
58 
59   delete [] UpdatedStmtList;
60 }
61 
VisitStmt(clang::Stmt * S)62 void RSASTReplace::VisitStmt(clang::Stmt *S) {
63   // This function does the actual iteration through all sub-Stmt's within
64   // a given Stmt. Note that this function is skipped by all of the other
65   // Visit* functions if we have already found a higher-level match.
66   for (clang::Stmt::child_iterator I = S->child_begin(), E = S->child_end();
67        I != E;
68        I++) {
69     if (clang::Stmt *Child = *I) {
70       if (!matchesStmt(Child)) {
71         Visit(Child);
72       }
73     }
74   }
75 }
76 
VisitCompoundStmt(clang::CompoundStmt * CS)77 void RSASTReplace::VisitCompoundStmt(clang::CompoundStmt *CS) {
78   VisitStmt(CS);
79   ReplaceInCompoundStmt(CS);
80 }
81 
VisitCaseStmt(clang::CaseStmt * CS)82 void RSASTReplace::VisitCaseStmt(clang::CaseStmt *CS) {
83   if (matchesStmt(CS->getSubStmt())) {
84     CS->setSubStmt(mNewStmt);
85   } else {
86     VisitStmt(CS);
87   }
88 }
89 
VisitDefaultStmt(clang::DefaultStmt * DS)90 void RSASTReplace::VisitDefaultStmt(clang::DefaultStmt *DS) {
91   if (matchesStmt(DS->getSubStmt())) {
92     DS->setSubStmt(mNewStmt);
93   } else {
94     VisitStmt(DS);
95   }
96 }
97 
VisitDoStmt(clang::DoStmt * DS)98 void RSASTReplace::VisitDoStmt(clang::DoStmt *DS) {
99   if (matchesExpr(DS->getCond())) {
100     DS->setCond(mNewExpr);
101   } else if (matchesStmt(DS->getBody())) {
102     DS->setBody(mNewStmt);
103   } else {
104     VisitStmt(DS);
105   }
106 }
107 
VisitForStmt(clang::ForStmt * FS)108 void RSASTReplace::VisitForStmt(clang::ForStmt *FS) {
109   if (matchesStmt(FS->getInit())) {
110     FS->setInit(mNewStmt);
111   } else if (matchesExpr(FS->getCond())) {
112     FS->setCond(mNewExpr);
113   } else if (matchesExpr(FS->getInc())) {
114     FS->setInc(mNewExpr);
115   } else if (matchesStmt(FS->getBody())) {
116     FS->setBody(mNewStmt);
117   } else {
118     VisitStmt(FS);
119   }
120 }
121 
VisitIfStmt(clang::IfStmt * IS)122 void RSASTReplace::VisitIfStmt(clang::IfStmt *IS) {
123   if (matchesExpr(IS->getCond())) {
124     IS->setCond(mNewExpr);
125   } else if (matchesStmt(IS->getThen())) {
126     IS->setThen(mNewStmt);
127   } else if (matchesStmt(IS->getElse())) {
128     IS->setElse(mNewStmt);
129   } else {
130     VisitStmt(IS);
131   }
132 }
133 
VisitSwitchCase(clang::SwitchCase * SC)134 void RSASTReplace::VisitSwitchCase(clang::SwitchCase *SC) {
135   slangAssert(false && "Both case and default have specialized handlers");
136   VisitStmt(SC);
137 }
138 
VisitSwitchStmt(clang::SwitchStmt * SS)139 void RSASTReplace::VisitSwitchStmt(clang::SwitchStmt *SS) {
140   if (matchesExpr(SS->getCond())) {
141     SS->setCond(mNewExpr);
142   } else {
143     VisitStmt(SS);
144   }
145 }
146 
VisitWhileStmt(clang::WhileStmt * WS)147 void RSASTReplace::VisitWhileStmt(clang::WhileStmt *WS) {
148   if (matchesExpr(WS->getCond())) {
149     WS->setCond(mNewExpr);
150   } else if (matchesStmt(WS->getBody())) {
151     WS->setBody(mNewStmt);
152   } else {
153     VisitStmt(WS);
154   }
155 }
156 
157 }  // namespace slang
158