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/IRReader.h"
12 #include "llvm/AsmParser/Parser.h"
13 #include "llvm/Bitcode/BitcodeReader.h"
14 #include "llvm/IR/LLVMContext.h"
15 #include "llvm/IR/Module.h"
16 #include "llvm/Support/MemoryBuffer.h"
17 #include "llvm/Support/SourceMgr.h"
18 #include "llvm/Support/Timer.h"
19 #include "llvm/Support/raw_ostream.h"
20 #include <system_error>
21 
22 using namespace llvm;
23 
24 namespace llvm {
25   extern bool TimePassesIsEnabled;
26 }
27 
28 static const char *const TimeIRParsingGroupName = "irparse";
29 static const char *const TimeIRParsingGroupDescription = "LLVM IR Parsing";
30 static const char *const TimeIRParsingName = "parse";
31 static const char *const TimeIRParsingDescription = "Parse IR";
32 
33 static std::unique_ptr<Module>
34 getLazyIRModule(std::unique_ptr<MemoryBuffer> Buffer, SMDiagnostic &Err,
35                 LLVMContext &Context, bool ShouldLazyLoadMetadata) {
36   if (isBitcode((const unsigned char *)Buffer->getBufferStart(),
37                 (const unsigned char *)Buffer->getBufferEnd())) {
38     Expected<std::unique_ptr<Module>> ModuleOrErr = getOwningLazyBitcodeModule(
39         std::move(Buffer), Context, ShouldLazyLoadMetadata);
40     if (Error E = ModuleOrErr.takeError()) {
41       handleAllErrors(std::move(E), [&](ErrorInfoBase &EIB) {
42         Err = SMDiagnostic(Buffer->getBufferIdentifier(), SourceMgr::DK_Error,
43                            EIB.message());
44       });
45       return nullptr;
46     }
47     return std::move(ModuleOrErr.get());
48   }
49 
50   return parseAssembly(Buffer->getMemBufferRef(), Err, Context);
51 }
52 
53 std::unique_ptr<Module> llvm::getLazyIRFileModule(StringRef Filename,
54                                                   SMDiagnostic &Err,
55                                                   LLVMContext &Context,
56                                                   bool ShouldLazyLoadMetadata) {
57   ErrorOr<std::unique_ptr<MemoryBuffer>> FileOrErr =
58       MemoryBuffer::getFileOrSTDIN(Filename);
59   if (std::error_code EC = FileOrErr.getError()) {
60     Err = SMDiagnostic(Filename, SourceMgr::DK_Error,
61                        "Could not open input file: " + EC.message());
62     return nullptr;
63   }
64 
65   return getLazyIRModule(std::move(FileOrErr.get()), Err, Context,
66                          ShouldLazyLoadMetadata);
67 }
68 
69 std::unique_ptr<Module> llvm::parseIR(MemoryBufferRef Buffer, SMDiagnostic &Err,
70                                       LLVMContext &Context,
71                                       bool UpgradeDebugInfo) {
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, nullptr, UpgradeDebugInfo);
90 }
91 
92 std::unique_ptr<Module> llvm::parseIRFile(StringRef Filename, SMDiagnostic &Err,
93                                           LLVMContext &Context,
94                                           bool UpgradeDebugInfo) {
95   ErrorOr<std::unique_ptr<MemoryBuffer>> FileOrErr =
96       MemoryBuffer::getFileOrSTDIN(Filename);
97   if (std::error_code EC = FileOrErr.getError()) {
98     Err = SMDiagnostic(Filename, SourceMgr::DK_Error,
99                        "Could not open input file: " + EC.message());
100     return nullptr;
101   }
102 
103   return parseIR(FileOrErr.get()->getMemBufferRef(), Err, Context,
104                  UpgradeDebugInfo);
105 }
106 
107 //===----------------------------------------------------------------------===//
108 // C API.
109 //===----------------------------------------------------------------------===//
110 
111 LLVMBool LLVMParseIRInContext(LLVMContextRef ContextRef,
112                               LLVMMemoryBufferRef MemBuf, LLVMModuleRef *OutM,
113                               char **OutMessage) {
114   SMDiagnostic Diag;
115 
116   std::unique_ptr<MemoryBuffer> MB(unwrap(MemBuf));
117   *OutM =
118       wrap(parseIR(MB->getMemBufferRef(), Diag, *unwrap(ContextRef)).release());
119 
120   if(!*OutM) {
121     if (OutMessage) {
122       std::string buf;
123       raw_string_ostream os(buf);
124 
125       Diag.print(nullptr, os, false);
126       os.flush();
127 
128       *OutMessage = strdup(buf.c_str());
129     }
130     return 1;
131   }
132 
133   return 0;
134 }
135