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 Module *llvm::getLazyIRFileModule(const std::string &Filename,
  53                                   SMDiagnostic &Err, LLVMContext &Context) {
  54   ErrorOr<std::unique_ptr<MemoryBuffer>> FileOrErr =
  55       MemoryBuffer::getFileOrSTDIN(Filename);
  56   if (std::error_code EC = FileOrErr.getError()) {
  57     Err = SMDiagnostic(Filename, SourceMgr::DK_Error,
  58                        "Could not open input file: " + EC.message());
  59     return nullptr;
  60   }
  61
  62   return getLazyIRModule(std::move(FileOrErr.get()), Err, Context).release();
  63 }
  64
  65 Module *llvm::ParseIR(MemoryBuffer *Buffer, SMDiagnostic &Err,
  66                       LLVMContext &Context) {
  67   NamedRegionTimer T(TimeIRParsingName, TimeIRParsingGroupName,
  68                      TimePassesIsEnabled);
  69   if (isBitcode((const unsigned char *)Buffer->getBufferStart(),
  70                 (const unsigned char *)Buffer->getBufferEnd())) {
  71     ErrorOr<Module *> ModuleOrErr = parseBitcodeFile(Buffer, Context);
  72     Module *M = nullptr;
  73     if (std::error_code EC = ModuleOrErr.getError())
  74       Err = SMDiagnostic(Buffer->getBufferIdentifier(), SourceMgr::DK_Error,
  75                          EC.message());
  76     else
  77       M = ModuleOrErr.get();
  78     // parseBitcodeFile does not take ownership of the Buffer.
  79     return M;
  80   }
  81
  82   return parseAssembly(std::unique_ptr<MemoryBuffer>(MemoryBuffer::getMemBuffer(
  83                            Buffer->getBuffer(), Buffer->getBufferIdentifier())),
  84                        Err, Context).release();
  85 }
  86
  87 Module *llvm::ParseIRFile(const std::string &Filename, SMDiagnostic &Err,
  88                           LLVMContext &Context) {
  89   ErrorOr<std::unique_ptr<MemoryBuffer>> FileOrErr =
  90       MemoryBuffer::getFileOrSTDIN(Filename);
  91   if (std::error_code EC = FileOrErr.getError()) {
  92     Err = SMDiagnostic(Filename, SourceMgr::DK_Error,
  93                        "Could not open input file: " + EC.message());
  94     return nullptr;
  95   }
  96
  97   return ParseIR(FileOrErr.get().get(), Err, Context);
  98 }
  99
 100 //===----------------------------------------------------------------------===//
 101 // C API.
 102 //===----------------------------------------------------------------------===//
 103
 104 LLVMBool LLVMParseIRInContext(LLVMContextRef ContextRef,
 105                               LLVMMemoryBufferRef MemBuf, LLVMModuleRef *OutM,
 106                               char **OutMessage) {
 107   SMDiagnostic Diag;
 108
 109   std::unique_ptr<MemoryBuffer> MB(unwrap(MemBuf));
 110   *OutM = wrap(ParseIR(MB.get(), Diag, *unwrap(ContextRef)));
 111
 112   if(!*OutM) {
 113     if (OutMessage) {
 114       std::string buf;
 115       raw_string_ostream os(buf);
 116
 117       Diag.print(nullptr, os, false);
 118       os.flush();
 119
 120       *OutMessage = strdup(buf.c_str());
 121     }
 122     return 1;
 123   }
 124
 125   return 0;
 126 }