1 //===---- IRReader.cpp - Reader for LLVM IR files -------------------------===//
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 #include "llvm/IRReader/IRReader.h"
11 #include "llvm-c/Core.h"
12 #include "llvm-c/IRReader.h"
13 #include "llvm/AsmParser/Parser.h"
14 #include "llvm/Bitcode/ReaderWriter.h"
15 #include "llvm/IR/LLVMContext.h"
16 #include "llvm/IR/Module.h"
17 #include "llvm/Support/MemoryBuffer.h"
18 #include "llvm/Support/SourceMgr.h"
19 #include "llvm/Support/Timer.h"
20 #include "llvm/Support/raw_ostream.h"
21 #include <system_error>
22 
23 using namespace llvm;
24 
25 namespace llvm {
26   extern bool TimePassesIsEnabled;
27 }
28 
29 static const char *const TimeIRParsingGroupName = "LLVM IR Parsing";
30 static const char *const TimeIRParsingName = "Parse IR";
31 
32 
33 Module *llvm::getLazyIRModule(MemoryBuffer *Buffer, SMDiagnostic &Err,
34                               LLVMContext &Context) {
35   if (isBitcode((const unsigned char *)Buffer->getBufferStart(),
36                 (const unsigned char *)Buffer->getBufferEnd())) {
37     std::string ErrMsg;
38     ErrorOr<Module *> ModuleOrErr = getLazyBitcodeModule(Buffer, Context);
39     if (std::error_code EC = ModuleOrErr.getError()) {
40       Err = SMDiagnostic(Buffer->getBufferIdentifier(), SourceMgr::DK_Error,
41                          EC.message());
42       // getLazyBitcodeModule does not take ownership of the Buffer in the
43       // case of an error.
44       delete Buffer;
45       return nullptr;
46     }
47     return ModuleOrErr.get();
48   }
49 
50   return ParseAssembly(Buffer, nullptr, Err, Context);
51 }
52 
53 Module *llvm::getLazyIRFileModule(const std::string &Filename, SMDiagnostic &Err,
54                                   LLVMContext &Context) {
55   std::unique_ptr<MemoryBuffer> File;
56   if (std::error_code ec = MemoryBuffer::getFileOrSTDIN(Filename, File)) {
57     Err = SMDiagnostic(Filename, SourceMgr::DK_Error,
58                        "Could not open input file: " + ec.message());
59     return nullptr;
60   }
61 
62   return getLazyIRModule(File.release(), Err, Context);
63 }
64 
65 Module *llvm::ParseIR(MemoryBuffer *Buffer, SMDiagnostic &Err,
66                       LLVMContext &Context) {
67   NamedRegionTimer T(TimeIRParsingName, TimeIRParsingGroupName,
68                      TimePassesIsEnabled);
69   if (isBitcode((const unsigned char *)Buffer->getBufferStart(),
70                 (const unsigned char *)Buffer->getBufferEnd())) {
71     ErrorOr<Module *> ModuleOrErr = parseBitcodeFile(Buffer, Context);
72     Module *M = nullptr;
73     if (std::error_code EC = ModuleOrErr.getError())
74       Err = SMDiagnostic(Buffer->getBufferIdentifier(), SourceMgr::DK_Error,
75                          EC.message());
76     else
77       M = ModuleOrErr.get();
78     // parseBitcodeFile does not take ownership of the Buffer.
79     return M;
80   }
81 
82   return ParseAssembly(MemoryBuffer::getMemBuffer(
83                            Buffer->getBuffer(), Buffer->getBufferIdentifier()),
84                        nullptr, Err, Context);
85 }
86 
87 Module *llvm::ParseIRFile(const std::string &Filename, SMDiagnostic &Err,
88                           LLVMContext &Context) {
89   std::unique_ptr<MemoryBuffer> File;
90   if (std::error_code ec = MemoryBuffer::getFileOrSTDIN(Filename, File)) {
91     Err = SMDiagnostic(Filename, SourceMgr::DK_Error,
92                        "Could not open input file: " + ec.message());
93     return nullptr;
94   }
95 
96   return ParseIR(File.get(), Err, Context);
97 }
98 
99 //===----------------------------------------------------------------------===//
100 // C API.
101 //===----------------------------------------------------------------------===//
102 
103 LLVMBool LLVMParseIRInContext(LLVMContextRef ContextRef,
104                               LLVMMemoryBufferRef MemBuf, LLVMModuleRef *OutM,
105                               char **OutMessage) {
106   SMDiagnostic Diag;
107 
108   std::unique_ptr<MemoryBuffer> MB(unwrap(MemBuf));
109   *OutM = wrap(ParseIR(MB.get(), Diag, *unwrap(ContextRef)));
110 
111   if(!*OutM) {
112     if (OutMessage) {
113       std::string buf;
114       raw_string_ostream os(buf);
115 
116       Diag.print(nullptr, os, false);
117       os.flush();
118 
119       *OutMessage = strdup(buf.c_str());
120     }
121     return 1;
122   }
123 
124   return 0;
125 }
126