Split out the IRReader header and the utility functions it provides into

its own library. These functions are bridging between the bitcode reader
and the ll parser which are in different libraries. Previously we didn't
have any good library to do this, and instead played fast and loose with
a "header only" set of interfaces in the Support library. This really
doesn't work well as evidenced by the recent attempt to add timing logic
to the these routines.

As part of this, make them normal functions rather than weird inline
functions, and sink the implementation into the library. Also clean up
the header to be nice and minimal.

This requires updating lots of build system dependencies to specify that
the IRReader library is needed, and several source files to not
implicitly rely upon the header file to transitively include all manner
of other headers.

If you are using IRReader.h, this commit will break you (the header
moved) and you'll need to also update your library usage to include
'irreader'. I will commit the corresponding change to Clang momentarily.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177971 91177308-0d34-0410-b5e6-96231b3b80d8

lib/CMakeLists.txt

@@ -1,6 +1,7 @@
 # `Support' and `TableGen' libraries are added on the top-level CMakeLists.txt
 
 add_subdirectory(IR)
+add_subdirectory(IRReader)
 add_subdirectory(CodeGen)
 add_subdirectory(Bitcode)
 add_subdirectory(Transforms)

lib/IRReader/CMakeLists.txt

@@ -0,0 +1,3 @@
+add_llvm_library(LLVMIRReader
+  IRReader.cpp
+  )

lib/IRReader/IRReader.cpp

@@ -0,0 +1,78 @@
+//===---- IRReader.cpp - Reader for LLVM IR files -------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/IRReader/IRReader.h"
+#include "llvm/ADT/OwningPtr.h"
+#include "llvm/Assembly/Parser.h"
+#include "llvm/Bitcode/ReaderWriter.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/SourceMgr.h"
+#include "llvm/Support/system_error.h"
+
+using namespace llvm;
+
+Module *llvm::getLazyIRModule(MemoryBuffer *Buffer, SMDiagnostic &Err,
+                        LLVMContext &Context) {
+  if (isBitcode((const unsigned char *)Buffer->getBufferStart(),
+                (const unsigned char *)Buffer->getBufferEnd())) {
+    std::string ErrMsg;
+    Module *M = getLazyBitcodeModule(Buffer, Context, &ErrMsg);
+    if (M == 0) {
+      Err = SMDiagnostic(Buffer->getBufferIdentifier(), SourceMgr::DK_Error,
+                         ErrMsg);
+      // ParseBitcodeFile does not take ownership of the Buffer in the
+      // case of an error.
+      delete Buffer;
+    }
+    return M;
+  }
+
+  return ParseAssembly(Buffer, 0, Err, Context);
+}
+
+Module *llvm::getLazyIRFileModule(const std::string &Filename, SMDiagnostic &Err,
+                            LLVMContext &Context) {
+  OwningPtr<MemoryBuffer> File;
+  if (error_code ec = MemoryBuffer::getFileOrSTDIN(Filename.c_str(), File)) {
+    Err = SMDiagnostic(Filename, SourceMgr::DK_Error,
+                       "Could not open input file: " + ec.message());
+    return 0;
+  }
+
+  return getLazyIRModule(File.take(), Err, Context);
+}
+
+Module *llvm::ParseIR(MemoryBuffer *Buffer, SMDiagnostic &Err,
+                      LLVMContext &Context) {
+  if (isBitcode((const unsigned char *)Buffer->getBufferStart(),
+                (const unsigned char *)Buffer->getBufferEnd())) {
+    std::string ErrMsg;
+    Module *M = ParseBitcodeFile(Buffer, Context, &ErrMsg);
+    if (M == 0)
+      Err = SMDiagnostic(Buffer->getBufferIdentifier(), SourceMgr::DK_Error,
+                         ErrMsg);
+    // ParseBitcodeFile does not take ownership of the Buffer.
+    delete Buffer;
+    return M;
+  }
+
+  return ParseAssembly(Buffer, 0, Err, Context);
+}
+
+Module *llvm::ParseIRFile(const std::string &Filename, SMDiagnostic &Err,
+                          LLVMContext &Context) {
+  OwningPtr<MemoryBuffer> File;
+  if (error_code ec = MemoryBuffer::getFileOrSTDIN(Filename.c_str(), File)) {
+    Err = SMDiagnostic(Filename, SourceMgr::DK_Error,
+                       "Could not open input file: " + ec.message());
+    return 0;
+  }
+
+  return ParseIR(File.take(), Err, Context);
+}

lib/IRReader/LLVMBuild.txt

@@ -0,0 +1,22 @@
+;===- ./lib/AsmParser/LLVMBuild.txt ----------------------------*- Conf -*--===;
+;
+;                     The LLVM Compiler Infrastructure
+;
+; This file is distributed under the University of Illinois Open Source
+; License. See LICENSE.TXT for details.
+;
+;===------------------------------------------------------------------------===;
+;
+; This is an LLVMBuild description file for the components in this subdirectory.
+;
+; For more information on the LLVMBuild system, please see:
+;
+;   http://llvm.org/docs/LLVMBuild.html
+;
+;===------------------------------------------------------------------------===;
+
+[component_0]
+type = Library
+name = IRReader
+parent = Libraries
+required_libraries = AsmParser BitReader Core Support

lib/IRReader/Makefile

@@ -0,0 +1,14 @@
+##===- lib/IRReader/Makefile -------------------------------*- Makefile -*-===##
+#
+#                     The LLVM Compiler Infrastructure
+#
+# This file is distributed under the University of Illinois Open Source
+# License. See LICENSE.TXT for details.
+#
+##===----------------------------------------------------------------------===##
+
+LEVEL = ../..
+LIBRARYNAME := LLVMIRReader
+BUILD_ARCHIVE = 1
+
+include $(LEVEL)/Makefile.common

lib/LLVMBuild.txt

@@ -16,7 +16,7 @@
 ;===------------------------------------------------------------------------===;
 
 [common]
-subdirectories = Analysis Archive AsmParser Bitcode CodeGen DebugInfo ExecutionEngine Linker IR MC Object Option Support TableGen Target Transforms
+subdirectories = Analysis Archive AsmParser Bitcode CodeGen DebugInfo ExecutionEngine Linker IR IRReader MC Object Option Support TableGen Target Transforms
 
 [component_0]
 type = Group

lib/Makefile

@@ -11,7 +11,8 @@ LEVEL = ..
 include $(LEVEL)/Makefile.config
 
 PARALLEL_DIRS := IR AsmParser Bitcode Archive Analysis Transforms CodeGen \
-                Target ExecutionEngine Linker MC Object Option DebugInfo
+                 Target ExecutionEngine Linker MC Object Option DebugInfo \
+								 IRReader
 
 include $(LEVEL)/Makefile.common