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

4 files changed, 117 insertions, 0 deletions

diff --git a/lib/IRReader/CMakeLists.txt b/lib/IRReader/CMakeLists.txt
new file mode 100644
index 0000000000..cf10d8b7db
--- /dev/null
+++ b/lib/IRReader/CMakeLists.txt
@@ -0,0 +1,3 @@
+add_llvm_library(LLVMIRReader
+  IRReader.cpp
+  )
diff --git a/lib/IRReader/IRReader.cpp b/lib/IRReader/IRReader.cpp
new file mode 100644
index 0000000000..dff4c1fa43
--- /dev/null
+++ b/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);
+}
diff --git a/lib/IRReader/LLVMBuild.txt b/lib/IRReader/LLVMBuild.txt
new file mode 100644
index 0000000000..04a59bb871
--- /dev/null
+++ b/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
diff --git a/lib/IRReader/Makefile b/lib/IRReader/Makefile
new file mode 100644
index 0000000000..cf6bc11354
--- /dev/null
+++ b/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