From 23866d3902a3d34616b92e39c62539ab280740aa Mon Sep 17 00:00:00 2001
From: Peter Zotov <whitequark@whitequark.org>
Date: Wed, 6 Nov 2013 09:21:15 +0000
Subject: [PATCH] [llvm-c] Expose IRReader interface

Original patch by Chris Wailes

llvm-svn: 194137
---
 include/llvm-c/IRReader.h | 40 +++++++++++++++++++++++++++++++++++++++
 lib/IRReader/IRReader.cpp | 32 +++++++++++++++++++++++++++++++
 2 files changed, 72 insertions(+)
 create mode 100644 include/llvm-c/IRReader.h

diff --git a/include/llvm-c/IRReader.h b/include/llvm-c/IRReader.h
new file mode 100644
index 00000000000..d0a23be0abf
--- /dev/null
+++ b/include/llvm-c/IRReader.h
@@ -0,0 +1,40 @@
+/*===-- llvm-c/IRReader.h - IR Reader C Interface -----------------*- C -*-===*\
+|*                                                                            *|
+|*                     The LLVM Compiler Infrastructure                       *|
+|*                                                                            *|
+|* This file is distributed under the University of Illinois Open Source      *|
+|* License. See LICENSE.TXT for details.                                      *|
+|*                                                                            *|
+|*===----------------------------------------------------------------------===*|
+|*                                                                            *|
+|* This file defines the C interface to the IR Reader.                        *|
+|*                                                                            *|
+\*===----------------------------------------------------------------------===*/
+
+#ifndef LLVM_C_IRREADER_H
+#define LLVM_C_IRREADER_H
+
+#include "llvm-c/Core.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * Read LLVM IR from a memory buffer and convert it into an in-memory Module
+ * object. Returns 0 on success.
+ * Optionally returns a human-readable description of any errors that
+ * occured during parsing IR. OutMessage must be disposed with
+ * LLVMDisposeMessage.
+ *
+ * @see llvm::ParseIR()
+ */
+LLVMBool LLVMParseIRInContext(LLVMContextRef ContextRef,
+                              LLVMMemoryBufferRef MemBuf, LLVMModuleRef *OutM,
+                              char **OutMessage);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
diff --git a/lib/IRReader/IRReader.cpp b/lib/IRReader/IRReader.cpp
index 656fe183e8d..935e81d3c8c 100644
--- a/lib/IRReader/IRReader.cpp
+++ b/lib/IRReader/IRReader.cpp
@@ -11,10 +11,15 @@
 #include "llvm/ADT/OwningPtr.h"
 #include "llvm/Assembly/Parser.h"
 #include "llvm/Bitcode/ReaderWriter.h"
+#include "llvm/IR/LLVMContext.h"
+#include "llvm/IR/Module.h"
 #include "llvm/Support/MemoryBuffer.h"
 #include "llvm/Support/SourceMgr.h"
 #include "llvm/Support/system_error.h"
 #include "llvm/Support/Timer.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm-c/Core.h"
+#include "llvm-c/IRReader.h"
 
 using namespace llvm;
 
@@ -87,3 +92,30 @@ Module *llvm::ParseIRFile(const std::string &Filename, SMDiagnostic &Err,
 
   return ParseIR(File.take(), Err, Context);
 }
+
+//===----------------------------------------------------------------------===//
+// C API.
+//===----------------------------------------------------------------------===//
+
+LLVMBool LLVMParseIRInContext(LLVMContextRef ContextRef,
+                              LLVMMemoryBufferRef MemBuf, LLVMModuleRef *OutM,
+                              char **OutMessage) {
+  SMDiagnostic Diag;
+
+  *OutM = wrap(ParseIR(unwrap(MemBuf), Diag, *unwrap(ContextRef)));
+
+  if(!*OutM) {
+    if (OutMessage) {
+      std::string buf;
+      raw_string_ostream os(buf);
+
+      Diag.print(NULL, os, false);
+      os.flush();
+
+      *OutMessage = strdup(buf.c_str());
+    }
+    return 1;
+  }
+
+  return 0;
+}