Pass a MemoryBufferRef when we can avoid taking ownership.
[oota-llvm.git] / lib / IRReader / IRReader.cpp
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/ReaderWriter.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) {
35   if (isBitcode((const unsigned char *)Buffer->getBufferStart(),
36                 (const unsigned char *)Buffer->getBufferEnd())) {
37     std::string ErrMsg;
38     ErrorOr<Module *> ModuleOrErr = getLazyBitcodeModule(Buffer.get(), Context);
39     if (std::error_code EC = ModuleOrErr.getError()) {
40       Err = SMDiagnostic(Buffer->getBufferIdentifier(), SourceMgr::DK_Error,
41                          EC.message());
42       return nullptr;
43     }
44     // getLazyBitcodeModule takes ownership of the Buffer when successful.
45     Buffer.release();
46     return std::unique_ptr<Module>(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   ErrorOr<std::unique_ptr<MemoryBuffer>> FileOrErr =
56       MemoryBuffer::getFileOrSTDIN(Filename);
57   if (std::error_code EC = FileOrErr.getError()) {
58     Err = SMDiagnostic(Filename, SourceMgr::DK_Error,
59                        "Could not open input file: " + EC.message());
60     return nullptr;
61   }
62
63   return getLazyIRModule(std::move(FileOrErr.get()), Err, Context);
64 }
65
66 std::unique_ptr<Module> llvm::parseIR(MemoryBufferRef Buffer, SMDiagnostic &Err,
67                                       LLVMContext &Context) {
68   NamedRegionTimer T(TimeIRParsingName, TimeIRParsingGroupName,
69                      TimePassesIsEnabled);
70   if (isBitcode((const unsigned char *)Buffer.getBufferStart(),
71                 (const unsigned char *)Buffer.getBufferEnd())) {
72     ErrorOr<Module *> ModuleOrErr = parseBitcodeFile(Buffer, Context);
73     if (std::error_code EC = ModuleOrErr.getError()) {
74       Err = SMDiagnostic(Buffer.getBufferIdentifier(), SourceMgr::DK_Error,
75                          EC.message());
76       return nullptr;
77     }
78     return std::unique_ptr<Module>(ModuleOrErr.get());
79   }
80
81   return parseAssembly(Buffer, Err, Context);
82 }
83
84 std::unique_ptr<Module> llvm::parseIRFile(StringRef Filename, SMDiagnostic &Err,
85                                           LLVMContext &Context) {
86   ErrorOr<std::unique_ptr<MemoryBuffer>> FileOrErr =
87       MemoryBuffer::getFileOrSTDIN(Filename);
88   if (std::error_code EC = FileOrErr.getError()) {
89     Err = SMDiagnostic(Filename, SourceMgr::DK_Error,
90                        "Could not open input file: " + EC.message());
91     return nullptr;
92   }
93
94   return parseIR(FileOrErr.get()->getMemBufferRef(), Err, Context);
95 }
96
97 //===----------------------------------------------------------------------===//
98 // C API.
99 //===----------------------------------------------------------------------===//
100
101 LLVMBool LLVMParseIRInContext(LLVMContextRef ContextRef,
102                               LLVMMemoryBufferRef MemBuf, LLVMModuleRef *OutM,
103                               char **OutMessage) {
104   SMDiagnostic Diag;
105
106   std::unique_ptr<MemoryBuffer> MB(unwrap(MemBuf));
107   *OutM =
108       wrap(parseIR(MB->getMemBufferRef(), Diag, *unwrap(ContextRef)).release());
109
110   if(!*OutM) {
111     if (OutMessage) {
112       std::string buf;
113       raw_string_ostream os(buf);
114
115       Diag.print(nullptr, os, false);
116       os.flush();
117
118       *OutMessage = strdup(buf.c_str());
119     }
120     return 1;
121   }
122
123   return 0;
124 }