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(std::move(Buffer), 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(MemoryBuffer *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(std::unique_ptr<MemoryBuffer>(MemoryBuffer::getMemBuffer(
  82                            Buffer->getBuffer(), Buffer->getBufferIdentifier())),
  83                        Err, Context);
  84 }
  85
  86 std::unique_ptr<Module> llvm::parseIRFile(StringRef Filename, SMDiagnostic &Err,
  87                                           LLVMContext &Context) {
  88   ErrorOr<std::unique_ptr<MemoryBuffer>> FileOrErr =
  89       MemoryBuffer::getFileOrSTDIN(Filename);
  90   if (std::error_code EC = FileOrErr.getError()) {
  91     Err = SMDiagnostic(Filename, SourceMgr::DK_Error,
  92                        "Could not open input file: " + EC.message());
  93     return nullptr;
  94   }
  95
  96   return parseIR(FileOrErr.get().get(), Err, Context);
  97 }
  98
  99 //===----------------------------------------------------------------------===//
 100 // C API.
 101 //===----------------------------------------------------------------------===//
 102
 103 LLVMBool LLVMParseIRInContext(LLVMContextRef ContextRef,
 104                               LLVMMemoryBufferRef MemBuf, LLVMModuleRef *OutM,
 105                               char **OutMessage) {
 106   SMDiagnostic Diag;
 107
 108   std::unique_ptr<MemoryBuffer> MB(unwrap(MemBuf));
 109   *OutM = wrap(parseIR(MB.get(), Diag, *unwrap(ContextRef)).release());
 110
 111   if(!*OutM) {
 112     if (OutMessage) {
 113       std::string buf;
 114       raw_string_ostream os(buf);
 115
 116       Diag.print(nullptr, os, false);
 117       os.flush();
 118
 119       *OutMessage = strdup(buf.c_str());
 120     }
 121     return 1;
 122   }
 123
 124   return 0;
 125 }