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/BitcodeReader.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, bool ShouldLazyLoadMetadata) {
35   if (isBitcode((const unsigned char *)Buffer->getBufferStart(),
36                 (const unsigned char *)Buffer->getBufferEnd())) {
37     Expected<std::unique_ptr<Module>> ModuleOrErr = getOwningLazyBitcodeModule(
38         std::move(Buffer), Context, ShouldLazyLoadMetadata);
39     if (Error E = ModuleOrErr.takeError()) {
40       handleAllErrors(std::move(E), [&](ErrorInfoBase &EIB) {
41         Err = SMDiagnostic(Buffer->getBufferIdentifier(), SourceMgr::DK_Error,
42                            EIB.message());
43       });
44       return nullptr;
45     }
46     return std::move(ModuleOrErr.get());
47   }
48 
49   return parseAssembly(Buffer->getMemBufferRef(), Err, Context);
50 }
51 
52 std::unique_ptr<Module> llvm::getLazyIRFileModule(StringRef Filename,
53                                                   SMDiagnostic &Err,
54                                                   LLVMContext &Context,
55                                                   bool ShouldLazyLoadMetadata) {
56   ErrorOr<std::unique_ptr<MemoryBuffer>> FileOrErr =
57       MemoryBuffer::getFileOrSTDIN(Filename);
58   if (std::error_code EC = FileOrErr.getError()) {
59     Err = SMDiagnostic(Filename, SourceMgr::DK_Error,
60                        "Could not open input file: " + EC.message());
61     return nullptr;
62   }
63 
64   return getLazyIRModule(std::move(FileOrErr.get()), Err, Context,
65                          ShouldLazyLoadMetadata);
66 }
67 
68 std::unique_ptr<Module> llvm::parseIR(MemoryBufferRef Buffer, SMDiagnostic &Err,
69                                       LLVMContext &Context) {
70   NamedRegionTimer T(TimeIRParsingName, TimeIRParsingGroupName,
71                      TimePassesIsEnabled);
72   if (isBitcode((const unsigned char *)Buffer.getBufferStart(),
73                 (const unsigned char *)Buffer.getBufferEnd())) {
74     Expected<std::unique_ptr<Module>> ModuleOrErr =
75         parseBitcodeFile(Buffer, Context);
76     if (Error E = ModuleOrErr.takeError()) {
77       handleAllErrors(std::move(E), [&](ErrorInfoBase &EIB) {
78         Err = SMDiagnostic(Buffer.getBufferIdentifier(), SourceMgr::DK_Error,
79                            EIB.message());
80       });
81       return nullptr;
82     }
83     return std::move(ModuleOrErr.get());
84   }
85 
86   return parseAssembly(Buffer, Err, Context);
87 }
88 
89 std::unique_ptr<Module> llvm::parseIRFile(StringRef Filename, SMDiagnostic &Err,
90                                           LLVMContext &Context) {
91   ErrorOr<std::unique_ptr<MemoryBuffer>> FileOrErr =
92       MemoryBuffer::getFileOrSTDIN(Filename);
93   if (std::error_code EC = FileOrErr.getError()) {
94     Err = SMDiagnostic(Filename, SourceMgr::DK_Error,
95                        "Could not open input file: " + EC.message());
96     return nullptr;
97   }
98 
99   return parseIR(FileOrErr.get()->getMemBufferRef(), Err, Context);
100 }
101 
102 //===----------------------------------------------------------------------===//
103 // C API.
104 //===----------------------------------------------------------------------===//
105 
106 LLVMBool LLVMParseIRInContext(LLVMContextRef ContextRef,
107                               LLVMMemoryBufferRef MemBuf, LLVMModuleRef *OutM,
108                               char **OutMessage) {
109   SMDiagnostic Diag;
110 
111   std::unique_ptr<MemoryBuffer> MB(unwrap(MemBuf));
112   *OutM =
113       wrap(parseIR(MB->getMemBufferRef(), Diag, *unwrap(ContextRef)).release());
114 
115   if(!*OutM) {
116     if (OutMessage) {
117       std::string buf;
118       raw_string_ostream os(buf);
119 
120       Diag.print(nullptr, os, false);
121       os.flush();
122 
123       *OutMessage = strdup(buf.c_str());
124     }
125     return 1;
126   }
127 
128   return 0;
129 }
130