1 //===---- IRReader.cpp - Reader for LLVM IR files -------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "llvm/IRReader/IRReader.h"
10 #include "llvm-c/IRReader.h"
11 #include "llvm/AsmParser/Parser.h"
12 #include "llvm/Bitcode/BitcodeReader.h"
13 #include "llvm/IR/LLVMContext.h"
14 #include "llvm/IR/Module.h"
15 #include "llvm/Support/MemoryBuffer.h"
16 #include "llvm/Support/SourceMgr.h"
17 #include "llvm/Support/Timer.h"
18 #include "llvm/Support/raw_ostream.h"
19 #include <system_error>
20 
21 using namespace llvm;
22 
23 namespace llvm {
24   extern bool TimePassesIsEnabled;
25 }
26 
27 const char TimeIRParsingGroupName[] = "irparse";
28 const char TimeIRParsingGroupDescription[] = "LLVM IR Parsing";
29 const char TimeIRParsingName[] = "parse";
30 const char TimeIRParsingDescription[] = "Parse IR";
31 
32 std::unique_ptr<Module>
33 llvm::getLazyIRModule(std::unique_ptr<MemoryBuffer> Buffer, SMDiagnostic &Err,
34                       LLVMContext &Context, bool ShouldLazyLoadMetadata) {
35   if (isBitcode((const unsigned char *)Buffer->getBufferStart(),
36                 (const unsigned char *)Buffer->getBufferEnd())) {
37     Expected<std::unique_ptr<Module>> ModuleOrErr = getOwningLazyBitcodeModule(
38         std::move(Buffer), Context, ShouldLazyLoadMetadata);
39     if (Error E = ModuleOrErr.takeError()) {
40       handleAllErrors(std::move(E), [&](ErrorInfoBase &EIB) {
41         Err = SMDiagnostic(Buffer->getBufferIdentifier(), SourceMgr::DK_Error,
42                            EIB.message());
43       });
44       return nullptr;
45     }
46     return std::move(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                                                   bool ShouldLazyLoadMetadata) {
56   ErrorOr<std::unique_ptr<MemoryBuffer>> FileOrErr =
57       MemoryBuffer::getFileOrSTDIN(Filename);
58   if (std::error_code EC = FileOrErr.getError()) {
59     Err = SMDiagnostic(Filename, SourceMgr::DK_Error,
60                        "Could not open input file: " + EC.message());
61     return nullptr;
62   }
63 
64   return getLazyIRModule(std::move(FileOrErr.get()), Err, Context,
65                          ShouldLazyLoadMetadata);
66 }
67 
68 std::unique_ptr<Module> llvm::parseIR(MemoryBufferRef Buffer, SMDiagnostic &Err,
69                                       LLVMContext &Context,
70                                       DataLayoutCallbackTy DataLayoutCallback) {
71   NamedRegionTimer T(TimeIRParsingName, TimeIRParsingDescription,
72                      TimeIRParsingGroupName, TimeIRParsingGroupDescription,
73                      TimePassesIsEnabled);
74   if (isBitcode((const unsigned char *)Buffer.getBufferStart(),
75                 (const unsigned char *)Buffer.getBufferEnd())) {
76     Expected<std::unique_ptr<Module>> ModuleOrErr =
77         parseBitcodeFile(Buffer, Context, DataLayoutCallback);
78     if (Error E = ModuleOrErr.takeError()) {
79       handleAllErrors(std::move(E), [&](ErrorInfoBase &EIB) {
80         Err = SMDiagnostic(Buffer.getBufferIdentifier(), SourceMgr::DK_Error,
81                            EIB.message());
82       });
83       return nullptr;
84     }
85     return std::move(ModuleOrErr.get());
86   }
87 
88   return parseAssembly(Buffer, Err, Context, nullptr, DataLayoutCallback);
89 }
90 
91 std::unique_ptr<Module>
92 llvm::parseIRFile(StringRef Filename, SMDiagnostic &Err, LLVMContext &Context,
93                   DataLayoutCallbackTy DataLayoutCallback) {
94   ErrorOr<std::unique_ptr<MemoryBuffer>> FileOrErr =
95       MemoryBuffer::getFileOrSTDIN(Filename, /*FileSize*/ -1,
96                                    /*RequiresNullTerminator*/ true,
97                                    /*IsText*/ true);
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                  DataLayoutCallback);
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