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 = "irparse";
30 static const char *const TimeIRParsingGroupDescription = "LLVM IR Parsing";
31 static const char *const TimeIRParsingName = "parse";
32 static const char *const TimeIRParsingDescription = "Parse IR";
33 
34 static std::unique_ptr<Module>
35 getLazyIRModule(std::unique_ptr<MemoryBuffer> Buffer, SMDiagnostic &Err,
36                 LLVMContext &Context, bool ShouldLazyLoadMetadata) {
37   if (isBitcode((const unsigned char *)Buffer->getBufferStart(),
38                 (const unsigned char *)Buffer->getBufferEnd())) {
39     Expected<std::unique_ptr<Module>> ModuleOrErr = getOwningLazyBitcodeModule(
40         std::move(Buffer), Context, ShouldLazyLoadMetadata);
41     if (Error E = ModuleOrErr.takeError()) {
42       handleAllErrors(std::move(E), [&](ErrorInfoBase &EIB) {
43         Err = SMDiagnostic(Buffer->getBufferIdentifier(), SourceMgr::DK_Error,
44                            EIB.message());
45       });
46       return nullptr;
47     }
48     return std::move(ModuleOrErr.get());
49   }
50 
51   return parseAssembly(Buffer->getMemBufferRef(), Err, Context);
52 }
53 
54 std::unique_ptr<Module> llvm::getLazyIRFileModule(StringRef Filename,
55                                                   SMDiagnostic &Err,
56                                                   LLVMContext &Context,
57                                                   bool ShouldLazyLoadMetadata) {
58   ErrorOr<std::unique_ptr<MemoryBuffer>> FileOrErr =
59       MemoryBuffer::getFileOrSTDIN(Filename);
60   if (std::error_code EC = FileOrErr.getError()) {
61     Err = SMDiagnostic(Filename, SourceMgr::DK_Error,
62                        "Could not open input file: " + EC.message());
63     return nullptr;
64   }
65 
66   return getLazyIRModule(std::move(FileOrErr.get()), Err, Context,
67                          ShouldLazyLoadMetadata);
68 }
69 
70 std::unique_ptr<Module> llvm::parseIR(MemoryBufferRef Buffer, SMDiagnostic &Err,
71                                       LLVMContext &Context) {
72   NamedRegionTimer T(TimeIRParsingName, TimeIRParsingDescription,
73                      TimeIRParsingGroupName, TimeIRParsingGroupDescription,
74                      TimePassesIsEnabled);
75   if (isBitcode((const unsigned char *)Buffer.getBufferStart(),
76                 (const unsigned char *)Buffer.getBufferEnd())) {
77     Expected<std::unique_ptr<Module>> ModuleOrErr =
78         parseBitcodeFile(Buffer, Context);
79     if (Error E = ModuleOrErr.takeError()) {
80       handleAllErrors(std::move(E), [&](ErrorInfoBase &EIB) {
81         Err = SMDiagnostic(Buffer.getBufferIdentifier(), SourceMgr::DK_Error,
82                            EIB.message());
83       });
84       return nullptr;
85     }
86     return std::move(ModuleOrErr.get());
87   }
88 
89   return parseAssembly(Buffer, Err, Context);
90 }
91 
92 std::unique_ptr<Module> llvm::parseIRFile(StringRef Filename, SMDiagnostic &Err,
93                                           LLVMContext &Context) {
94   ErrorOr<std::unique_ptr<MemoryBuffer>> FileOrErr =
95       MemoryBuffer::getFileOrSTDIN(Filename);
96   if (std::error_code EC = FileOrErr.getError()) {
97     Err = SMDiagnostic(Filename, SourceMgr::DK_Error,
98                        "Could not open input file: " + EC.message());
99     return nullptr;
100   }
101 
102   return parseIR(FileOrErr.get()->getMemBufferRef(), Err, Context);
103 }
104 
105 //===----------------------------------------------------------------------===//
106 // C API.
107 //===----------------------------------------------------------------------===//
108 
109 LLVMBool LLVMParseIRInContext(LLVMContextRef ContextRef,
110                               LLVMMemoryBufferRef MemBuf, LLVMModuleRef *OutM,
111                               char **OutMessage) {
112   SMDiagnostic Diag;
113 
114   std::unique_ptr<MemoryBuffer> MB(unwrap(MemBuf));
115   *OutM =
116       wrap(parseIR(MB->getMemBufferRef(), Diag, *unwrap(ContextRef)).release());
117 
118   if(!*OutM) {
119     if (OutMessage) {
120       std::string buf;
121       raw_string_ostream os(buf);
122 
123       Diag.print(nullptr, os, false);
124       os.flush();
125 
126       *OutMessage = strdup(buf.c_str());
127     }
128     return 1;
129   }
130 
131   return 0;
132 }
133