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 static std::unique_ptr<Module>
33 getLazyIRModule(std::unique_ptr<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 =
39         getLazyBitcodeModule(std::move(Buffer), Context);
40     if (std::error_code EC = ModuleOrErr.getError()) {
41       Err = SMDiagnostic(Buffer->getBufferIdentifier(), SourceMgr::DK_Error,
42                          EC.message());
43       return nullptr;
44     }
45     return std::unique_ptr<Module>(ModuleOrErr.get());
46   }
47 
48   return parseAssembly(Buffer->getMemBufferRef(), Err, Context);
49 }
50 
51 std::unique_ptr<Module> llvm::getLazyIRFileModule(StringRef Filename,
52                                                   SMDiagnostic &Err,
53                                                   LLVMContext &Context) {
54   ErrorOr<std::unique_ptr<MemoryBuffer>> FileOrErr =
55       MemoryBuffer::getFileOrSTDIN(Filename);
56   if (std::error_code EC = FileOrErr.getError()) {
57     Err = SMDiagnostic(Filename, SourceMgr::DK_Error,
58                        "Could not open input file: " + EC.message());
59     return nullptr;
60   }
61 
62   return getLazyIRModule(std::move(FileOrErr.get()), Err, Context);
63 }
64 
65 std::unique_ptr<Module> llvm::parseIR(MemoryBufferRef 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     if (std::error_code EC = ModuleOrErr.getError()) {
73       Err = SMDiagnostic(Buffer.getBufferIdentifier(), SourceMgr::DK_Error,
74                          EC.message());
75       return nullptr;
76     }
77     return std::unique_ptr<Module>(ModuleOrErr.get());
78   }
79 
80   return parseAssembly(Buffer, Err, Context);
81 }
82 
83 std::unique_ptr<Module> llvm::parseIRFile(StringRef Filename, SMDiagnostic &Err,
84                                           LLVMContext &Context) {
85   ErrorOr<std::unique_ptr<MemoryBuffer>> FileOrErr =
86       MemoryBuffer::getFileOrSTDIN(Filename);
87   if (std::error_code EC = FileOrErr.getError()) {
88     Err = SMDiagnostic(Filename, SourceMgr::DK_Error,
89                        "Could not open input file: " + EC.message());
90     return nullptr;
91   }
92 
93   return parseIR(FileOrErr.get()->getMemBufferRef(), Err, Context);
94 }
95 
96 //===----------------------------------------------------------------------===//
97 // C API.
98 //===----------------------------------------------------------------------===//
99 
100 LLVMBool LLVMParseIRInContext(LLVMContextRef ContextRef,
101                               LLVMMemoryBufferRef MemBuf, LLVMModuleRef *OutM,
102                               char **OutMessage) {
103   SMDiagnostic Diag;
104 
105   std::unique_ptr<MemoryBuffer> MB(unwrap(MemBuf));
106   *OutM =
107       wrap(parseIR(MB->getMemBufferRef(), Diag, *unwrap(ContextRef)).release());
108 
109   if(!*OutM) {
110     if (OutMessage) {
111       std::string buf;
112       raw_string_ostream os(buf);
113 
114       Diag.print(nullptr, os, false);
115       os.flush();
116 
117       *OutMessage = strdup(buf.c_str());
118     }
119     return 1;
120   }
121 
122   return 0;
123 }
124