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                                       bool UpgradeDebugInfo) {
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     return std::move(ModuleOrErr.get());
88   }
89 
90   return parseAssembly(Buffer, Err, Context, nullptr, UpgradeDebugInfo);
91 }
92 
93 std::unique_ptr<Module> llvm::parseIRFile(StringRef Filename, SMDiagnostic &Err,
94                                           LLVMContext &Context,
95                                           bool UpgradeDebugInfo) {
96   ErrorOr<std::unique_ptr<MemoryBuffer>> FileOrErr =
97       MemoryBuffer::getFileOrSTDIN(Filename);
98   if (std::error_code EC = FileOrErr.getError()) {
99     Err = SMDiagnostic(Filename, SourceMgr::DK_Error,
100                        "Could not open input file: " + EC.message());
101     return nullptr;
102   }
103 
104   return parseIR(FileOrErr.get()->getMemBufferRef(), Err, Context,
105                  UpgradeDebugInfo);
106 }
107 
108 //===----------------------------------------------------------------------===//
109 // C API.
110 //===----------------------------------------------------------------------===//
111 
112 LLVMBool LLVMParseIRInContext(LLVMContextRef ContextRef,
113                               LLVMMemoryBufferRef MemBuf, LLVMModuleRef *OutM,
114                               char **OutMessage) {
115   SMDiagnostic Diag;
116 
117   std::unique_ptr<MemoryBuffer> MB(unwrap(MemBuf));
118   *OutM =
119       wrap(parseIR(MB->getMemBufferRef(), Diag, *unwrap(ContextRef)).release());
120 
121   if(!*OutM) {
122     if (OutMessage) {
123       std::string buf;
124       raw_string_ostream os(buf);
125 
126       Diag.print(nullptr, os, false);
127       os.flush();
128 
129       *OutMessage = strdup(buf.c_str());
130     }
131     return 1;
132   }
133 
134   return 0;
135 }
136