Add malloc/new profiling on linux

src/LinuxMallocProfiling.h

+//===--- subzero/src/LinuxMallocProfiling.h - malloc/new tracing  ---------===//
+//
+//                        The Subzero Code Generator
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// \brief malloc/new/...caller tracing.
+///
+//===----------------------------------------------------------------------===//

[John, 2016/03/15 15:19:06]

you're missing the

#ifndef LINUXMALLOCPROFILING_H
#define LINUXMALLOCPROFILING_H

#endif // LINUXMALLOCPROFILING_H

[sehr, 2016/03/17 16:47:14]

Done.

+
+#include "IceDefs.h"
+#include "IceTypes.h"
+
+#include <iostream>
+
+namespace Ice {
+
+class LinuxMallocProfiling {
+ public:

[Jim Stichnoth, 2016/03/15 15:36:50]

This doesn't look like normal clang-format indentation...

[sehr, 2016/03/17 16:47:14]

Done.

+  explicit LinuxMallocProfiling(size_t NumThreads) {

[John, 2016/03/15 15:19:06]

can you move the definitions to the .cpp file so that iostream is not
transitively included in a bunch of places? (Note that there's no guard
preventing it from being included.)

[sehr, 2016/03/17 16:47:14]

Done.

+    if (NumThreads != 0) {
+#ifdef ALLOW_LINUX_MALLOC_PROFILE
+      std::cout << "NOTE: Malloc profiling is not thread safe.  "
+                << "Use --threads=0 to enable.\n";
+#endif // ALLOW_LINUX_MALLOC_PROFILE
+      return;
+    }
+    start();
+  }
+  ~LinuxMallocProfiling() {
+    end();
+  }
+
+ private:
+  LinuxMallocProfiling(const LinuxMallocProfiling&) = delete;

[John, 2016/03/15 15:19:06]

I honestly believe this is the proper place for deleting ctors and assignment
operators, but the stupid LLVM coding convention requires these deletions as the
first declarations in the class -- yeah, I am no a fan of the LLVM coding
style... :P

[sehr, 2016/03/17 16:47:14]

Done.

+  LinuxMallocProfiling &operator=(const LinuxMallocProfiling&) = delete;
+  static void start();

[John, 2016/03/15 15:19:06]

if you move the ctor/dtor implementation to the .cpp file you can simply inline
start/stop in those methods...

[sehr, 2016/03/17 16:47:14]

Done.

+  static void end();
+};
+
+} // end of namespace Ice