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                                       StringRef DataLayoutString) {
73   NamedRegionTimer T(TimeIRParsingName, TimeIRParsingDescription,
74                      TimeIRParsingGroupName, TimeIRParsingGroupDescription,
75                      TimePassesIsEnabled);
76   if (isBitcode((const unsigned char *)Buffer.getBufferStart(),
77                 (const unsigned char *)Buffer.getBufferEnd())) {
78     Expected<std::unique_ptr<Module>> ModuleOrErr =
79         parseBitcodeFile(Buffer, Context);
80     if (Error E = ModuleOrErr.takeError()) {
81       handleAllErrors(std::move(E), [&](ErrorInfoBase &EIB) {
82         Err = SMDiagnostic(Buffer.getBufferIdentifier(), SourceMgr::DK_Error,
83                            EIB.message());
84       });
85       return nullptr;
86     }
87     if (!DataLayoutString.empty())
88       ModuleOrErr.get()->setDataLayout(DataLayoutString);
89     return std::move(ModuleOrErr.get());
90   }
91 
92   return parseAssembly(Buffer, Err, Context, nullptr, UpgradeDebugInfo,
93                        DataLayoutString);
94 }
95 
96 std::unique_ptr<Module> llvm::parseIRFile(StringRef Filename, SMDiagnostic &Err,
97                                           LLVMContext &Context,
98                                           bool UpgradeDebugInfo,
99                                           StringRef DataLayoutString) {
100   ErrorOr<std::unique_ptr<MemoryBuffer>> FileOrErr =
101       MemoryBuffer::getFileOrSTDIN(Filename);
102   if (std::error_code EC = FileOrErr.getError()) {
103     Err = SMDiagnostic(Filename, SourceMgr::DK_Error,
104                        "Could not open input file: " + EC.message());
105     return nullptr;
106   }
107 
108   return parseIR(FileOrErr.get()->getMemBufferRef(), Err, Context,
109                  UpgradeDebugInfo, DataLayoutString);
110 }
111 
112 //===----------------------------------------------------------------------===//
113 // C API.
114 //===----------------------------------------------------------------------===//
115 
116 LLVMBool LLVMParseIRInContext(LLVMContextRef ContextRef,
117                               LLVMMemoryBufferRef MemBuf, LLVMModuleRef *OutM,
118                               char **OutMessage) {
119   SMDiagnostic Diag;
120 
121   std::unique_ptr<MemoryBuffer> MB(unwrap(MemBuf));
122   *OutM =
123       wrap(parseIR(MB->getMemBufferRef(), Diag, *unwrap(ContextRef)).release());
124 
125   if(!*OutM) {
126     if (OutMessage) {
127       std::string buf;
128       raw_string_ostream os(buf);
129 
130       Diag.print(nullptr, os, false);
131       os.flush();
132 
133       *OutMessage = strdup(buf.c_str());
134     }
135     return 1;
136   }
137 
138   return 0;
139 }
140