1 //===- BitcodeReader.h - Internal BitcodeReader impl ------------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This header defines the BitcodeReader class.
12 //===----------------------------------------------------------------------===//
14 #ifndef BITCODE_READER_H
15 #define BITCODE_READER_H
17 #include "llvm/GVMaterializer.h"
18 #include "llvm/Attributes.h"
19 #include "llvm/Type.h"
20 #include "llvm/OperandTraits.h"
21 #include "llvm/Bitcode/BitstreamReader.h"
22 #include "llvm/Bitcode/LLVMBitCodes.h"
23 #include "llvm/Support/ValueHandle.h"
24 #include "llvm/ADT/DenseMap.h"
31 //===----------------------------------------------------------------------===//
32 // BitcodeReaderValueList Class
33 //===----------------------------------------------------------------------===//
35 class BitcodeReaderValueList
{
36 std::vector
<WeakVH
> ValuePtrs
;
38 /// ResolveConstants - As we resolve forward-referenced constants, we add
39 /// information about them to this vector. This allows us to resolve them in
40 /// bulk instead of resolving each reference at a time. See the code in
41 /// ResolveConstantForwardRefs for more information about this.
43 /// The key of this vector is the placeholder constant, the value is the slot
44 /// number that holds the resolved value.
45 typedef std::vector
<std::pair
<Constant
*, unsigned> > ResolveConstantsTy
;
46 ResolveConstantsTy ResolveConstants
;
49 BitcodeReaderValueList(LLVMContext
&C
) : Context(C
) {}
50 ~BitcodeReaderValueList() {
51 assert(ResolveConstants
.empty() && "Constants not resolved?");
54 // vector compatibility methods
55 unsigned size() const { return ValuePtrs
.size(); }
56 void resize(unsigned N
) { ValuePtrs
.resize(N
); }
57 void push_back(Value
*V
) {
58 ValuePtrs
.push_back(V
);
62 assert(ResolveConstants
.empty() && "Constants not resolved?");
66 Value
*operator[](unsigned i
) const {
67 assert(i
< ValuePtrs
.size());
71 Value
*back() const { return ValuePtrs
.back(); }
72 void pop_back() { ValuePtrs
.pop_back(); }
73 bool empty() const { return ValuePtrs
.empty(); }
74 void shrinkTo(unsigned N
) {
75 assert(N
<= size() && "Invalid shrinkTo request!");
79 Constant
*getConstantFwdRef(unsigned Idx
, const Type
*Ty
);
80 Value
*getValueFwdRef(unsigned Idx
, const Type
*Ty
);
82 void AssignValue(Value
*V
, unsigned Idx
);
84 /// ResolveConstantForwardRefs - Once all constants are read, this method bulk
85 /// resolves any forward references.
86 void ResolveConstantForwardRefs();
90 //===----------------------------------------------------------------------===//
91 // BitcodeReaderMDValueList Class
92 //===----------------------------------------------------------------------===//
94 class BitcodeReaderMDValueList
{
95 std::vector
<WeakVH
> MDValuePtrs
;
99 BitcodeReaderMDValueList(LLVMContext
& C
) : Context(C
) {}
101 // vector compatibility methods
102 unsigned size() const { return MDValuePtrs
.size(); }
103 void resize(unsigned N
) { MDValuePtrs
.resize(N
); }
104 void push_back(Value
*V
) { MDValuePtrs
.push_back(V
); }
105 void clear() { MDValuePtrs
.clear(); }
106 Value
*back() const { return MDValuePtrs
.back(); }
107 void pop_back() { MDValuePtrs
.pop_back(); }
108 bool empty() const { return MDValuePtrs
.empty(); }
110 Value
*operator[](unsigned i
) const {
111 assert(i
< MDValuePtrs
.size());
112 return MDValuePtrs
[i
];
115 void shrinkTo(unsigned N
) {
116 assert(N
<= size() && "Invalid shrinkTo request!");
117 MDValuePtrs
.resize(N
);
120 Value
*getValueFwdRef(unsigned Idx
);
121 void AssignValue(Value
*V
, unsigned Idx
);
124 class BitcodeReader
: public GVMaterializer
{
125 LLVMContext
&Context
;
127 MemoryBuffer
*Buffer
;
129 BitstreamReader StreamFile
;
130 BitstreamCursor Stream
;
132 const char *ErrorString
;
134 std::vector
<Type
*> TypeList
;
135 BitcodeReaderValueList ValueList
;
136 BitcodeReaderMDValueList MDValueList
;
137 SmallVector
<Instruction
*, 64> InstructionList
;
139 std::vector
<std::pair
<GlobalVariable
*, unsigned> > GlobalInits
;
140 std::vector
<std::pair
<GlobalAlias
*, unsigned> > AliasInits
;
142 /// MAttributes - The set of attributes by index. Index zero in the
143 /// file is for null, and is thus not represented here. As such all indices
145 std::vector
<AttrListPtr
> MAttributes
;
147 /// FunctionBBs - While parsing a function body, this is a list of the basic
148 /// blocks for the function.
149 std::vector
<BasicBlock
*> FunctionBBs
;
151 // When reading the module header, this list is populated with functions that
152 // have bodies later in the file.
153 std::vector
<Function
*> FunctionsWithBodies
;
155 // When intrinsic functions are encountered which require upgrading they are
156 // stored here with their replacement function.
157 typedef std::vector
<std::pair
<Function
*, Function
*> > UpgradedIntrinsicMap
;
158 UpgradedIntrinsicMap UpgradedIntrinsics
;
160 // Map the bitcode's custom MDKind ID to the Module's MDKind ID.
161 DenseMap
<unsigned, unsigned> MDKindMap
;
163 // After the module header has been read, the FunctionsWithBodies list is
164 // reversed. This keeps track of whether we've done this yet.
165 bool HasReversedFunctionsWithBodies
;
167 /// DeferredFunctionInfo - When function bodies are initially scanned, this
168 /// map contains info about where to find deferred function body in the
170 DenseMap
<Function
*, uint64_t> DeferredFunctionInfo
;
172 /// BlockAddrFwdRefs - These are blockaddr references to basic blocks. These
173 /// are resolved lazily when functions are loaded.
174 typedef std::pair
<unsigned, GlobalVariable
*> BlockAddrRefTy
;
175 DenseMap
<Function
*, std::vector
<BlockAddrRefTy
> > BlockAddrFwdRefs
;
178 explicit BitcodeReader(MemoryBuffer
*buffer
, LLVMContext
&C
)
179 : Context(C
), TheModule(0), Buffer(buffer
), BufferOwned(false),
180 ErrorString(0), ValueList(C
), MDValueList(C
) {
181 HasReversedFunctionsWithBodies
= false;
189 /// setBufferOwned - If this is true, the reader will destroy the MemoryBuffer
190 /// when the reader is destroyed.
191 void setBufferOwned(bool Owned
) { BufferOwned
= Owned
; }
193 virtual bool isMaterializable(const GlobalValue
*GV
) const;
194 virtual bool isDematerializable(const GlobalValue
*GV
) const;
195 virtual bool Materialize(GlobalValue
*GV
, std::string
*ErrInfo
= 0);
196 virtual bool MaterializeModule(Module
*M
, std::string
*ErrInfo
= 0);
197 virtual void Dematerialize(GlobalValue
*GV
);
199 bool Error(const char *Str
) {
203 const char *getErrorString() const { return ErrorString
; }
205 /// @brief Main interface to parsing a bitcode buffer.
206 /// @returns true if an error occurred.
207 bool ParseBitcodeInto(Module
*M
);
209 /// @brief Cheap mechanism to just extract module triple
210 /// @returns true if an error occurred.
211 bool ParseTriple(std::string
&Triple
);
213 Type
*getTypeByID(unsigned ID
);
214 Type
*getTypeByIDOrNull(unsigned ID
);
215 Value
*getFnValueByID(unsigned ID
, const Type
*Ty
) {
216 if (Ty
&& Ty
->isMetadataTy())
217 return MDValueList
.getValueFwdRef(ID
);
218 return ValueList
.getValueFwdRef(ID
, Ty
);
220 BasicBlock
*getBasicBlock(unsigned ID
) const {
221 if (ID
>= FunctionBBs
.size()) return 0; // Invalid ID
222 return FunctionBBs
[ID
];
224 AttrListPtr
getAttributes(unsigned i
) const {
225 if (i
-1 < MAttributes
.size())
226 return MAttributes
[i
-1];
227 return AttrListPtr();
230 /// getValueTypePair - Read a value/type pair out of the specified record from
231 /// slot 'Slot'. Increment Slot past the number of slots used in the record.
232 /// Return true on failure.
233 bool getValueTypePair(SmallVector
<uint64_t, 64> &Record
, unsigned &Slot
,
234 unsigned InstNum
, Value
*&ResVal
) {
235 if (Slot
== Record
.size()) return true;
236 unsigned ValNo
= (unsigned)Record
[Slot
++];
237 if (ValNo
< InstNum
) {
238 // If this is not a forward reference, just return the value we already
240 ResVal
= getFnValueByID(ValNo
, 0);
242 } else if (Slot
== Record
.size()) {
246 unsigned TypeNo
= (unsigned)Record
[Slot
++];
247 ResVal
= getFnValueByID(ValNo
, getTypeByID(TypeNo
));
250 bool getValue(SmallVector
<uint64_t, 64> &Record
, unsigned &Slot
,
251 const Type
*Ty
, Value
*&ResVal
) {
252 if (Slot
== Record
.size()) return true;
253 unsigned ValNo
= (unsigned)Record
[Slot
++];
254 ResVal
= getFnValueByID(ValNo
, Ty
);
260 bool ParseAttributeBlock();
261 bool ParseTypeTable();
262 bool ParseOldTypeTable(); // FIXME: Remove in LLVM 3.1
263 bool ParseTypeTableBody();
265 bool ParseOldTypeSymbolTable(); // FIXME: Remove in LLVM 3.1
266 bool ParseValueSymbolTable();
267 bool ParseConstants();
268 bool RememberAndSkipFunctionBody();
269 bool ParseFunctionBody(Function
*F
);
270 bool ResolveGlobalAndAliasInits();
271 bool ParseMetadata();
272 bool ParseMetadataAttachment();
273 bool ParseModuleTriple(std::string
&Triple
);
276 } // End llvm namespace