• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 //===---- llvm/Support/IRReader.h - Reader for LLVM IR files ----*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file defines functions for reading LLVM IR. They support both
11 // Bitcode and Assembly, automatically detecting the input format.
12 //
13 // These functions must be defined in a header file in order to avoid
14 // library dependencies, since they reference both Bitcode and Assembly
15 // functions.
16 //
17 //===----------------------------------------------------------------------===//
18 
19 #ifndef LLVM_SUPPORT_IRREADER_H
20 #define LLVM_SUPPORT_IRREADER_H
21 
22 #include "llvm/ADT/OwningPtr.h"
23 #include "llvm/Assembly/Parser.h"
24 #include "llvm/Bitcode/ReaderWriter.h"
25 #include "llvm/Support/MemoryBuffer.h"
26 #include "llvm/Support/SourceMgr.h"
27 #include "llvm/Support/system_error.h"
28 
29 namespace llvm {
30 
31   /// If the given MemoryBuffer holds a bitcode image, return a Module for it
32   /// which does lazy deserialization of function bodies.  Otherwise, attempt to
33   /// parse it as LLVM Assembly and return a fully populated Module. This
34   /// function *always* takes ownership of the given MemoryBuffer.
getLazyIRModule(MemoryBuffer * Buffer,SMDiagnostic & Err,LLVMContext & Context)35   inline Module *getLazyIRModule(MemoryBuffer *Buffer,
36                                  SMDiagnostic &Err,
37                                  LLVMContext &Context) {
38     if (isBitcode((const unsigned char *)Buffer->getBufferStart(),
39                   (const unsigned char *)Buffer->getBufferEnd())) {
40       std::string ErrMsg;
41       Module *M = getLazyBitcodeModule(Buffer, Context, &ErrMsg);
42       if (M == 0) {
43         Err = SMDiagnostic(Buffer->getBufferIdentifier(), ErrMsg);
44         // ParseBitcodeFile does not take ownership of the Buffer in the
45         // case of an error.
46         delete Buffer;
47       }
48       return M;
49     }
50 
51     return ParseAssembly(Buffer, 0, Err, Context);
52   }
53 
54   /// If the given file holds a bitcode image, return a Module
55   /// for it which does lazy deserialization of function bodies.  Otherwise,
56   /// attempt to parse it as LLVM Assembly and return a fully populated
57   /// Module.
getLazyIRFileModule(const std::string & Filename,SMDiagnostic & Err,LLVMContext & Context)58   inline Module *getLazyIRFileModule(const std::string &Filename,
59                                      SMDiagnostic &Err,
60                                      LLVMContext &Context) {
61     OwningPtr<MemoryBuffer> File;
62     if (error_code ec = MemoryBuffer::getFileOrSTDIN(Filename.c_str(), File)) {
63       Err = SMDiagnostic(Filename,
64                          "Could not open input file: " + ec.message());
65       return 0;
66     }
67 
68     return getLazyIRModule(File.take(), Err, Context);
69   }
70 
71   /// If the given MemoryBuffer holds a bitcode image, return a Module
72   /// for it.  Otherwise, attempt to parse it as LLVM Assembly and return
73   /// a Module for it. This function *always* takes ownership of the given
74   /// MemoryBuffer.
ParseIR(MemoryBuffer * Buffer,SMDiagnostic & Err,LLVMContext & Context)75   inline Module *ParseIR(MemoryBuffer *Buffer,
76                          SMDiagnostic &Err,
77                          LLVMContext &Context) {
78     if (isBitcode((const unsigned char *)Buffer->getBufferStart(),
79                   (const unsigned char *)Buffer->getBufferEnd())) {
80       std::string ErrMsg;
81       Module *M = ParseBitcodeFile(Buffer, Context, &ErrMsg);
82       if (M == 0)
83         Err = SMDiagnostic(Buffer->getBufferIdentifier(), ErrMsg);
84       // ParseBitcodeFile does not take ownership of the Buffer.
85       delete Buffer;
86       return M;
87     }
88 
89     return ParseAssembly(Buffer, 0, Err, Context);
90   }
91 
92   /// If the given file holds a bitcode image, return a Module for it.
93   /// Otherwise, attempt to parse it as LLVM Assembly and return a Module
94   /// for it.
ParseIRFile(const std::string & Filename,SMDiagnostic & Err,LLVMContext & Context)95   inline Module *ParseIRFile(const std::string &Filename,
96                              SMDiagnostic &Err,
97                              LLVMContext &Context) {
98     OwningPtr<MemoryBuffer> File;
99     if (error_code ec = MemoryBuffer::getFileOrSTDIN(Filename.c_str(), File)) {
100       Err = SMDiagnostic(Filename,
101                          "Could not open input file: " + ec.message());
102       return 0;
103     }
104 
105     return ParseIR(File.take(), Err, Context);
106   }
107 
108 }
109 
110 #endif
111