Revert r276117 "[XRay] Basic initialization and flag definition for XRay runtime"

and also the follow-up "[xray] Only build xray on Linux for now"

Two build errors were reported on the llvm-commits list:

	[ 88%] Building CXX object lib/xray/CMakeFiles/clang_rt.xray-x86_64.dir/xray_flags.cc.o
	/mnt/b/sanitizer-buildbot1/sanitizer-x86_64-linux/build/llvm/projects/compiler-rt/lib/xray/xray_init.cc:23:10: fatal error: 'llvm/Support/ELF.h' file not found
  #include "llvm/Support/ELF.h"
					 ^

and

	In file included from /w/src/llvm.org/projects/compiler-rt/lib/xray/xray_interface.cc:16:
	/w/src/llvm.org/projects/compiler-rt/lib/xray/xray_interface_internal.h:36:8: error:
				no type named 'size_t' in namespace 'std'
		std::size_t Entries;
		~~~~~^

llvm-svn: 276186

1 files changed, 0 insertions, 68 deletions

diff --git a/compiler-rt/lib/xray/xray_init.cc b/compiler-rt/lib/xray/xray_init.cc
deleted file mode 100644
index be5d762675f..00000000000
--- a/compiler-rt/lib/xray/xray_init.cc
+++ /dev/null
@@ -1,68 +0,0 @@
-//===-- xray_init.cc --------------------------------------------*- C++ -*-===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-// This file is a part of XRay, a dynamic runtime instrumentation system.
-//
-// XRay initialisation logic.
-//===----------------------------------------------------------------------===//
-
-#include <atomic>
-#include <fcntl.h>
-#include <strings.h>
-#include <unistd.h>
-
-#include "sanitizer_common/sanitizer_common.h"
-#include "xray_flags.h"
-#include "xray_interface_internal.h"
-#include "llvm/Support/ELF.h"
-
-extern "C" {
-extern void __xray_init();
-extern const XRaySledEntry __start_xray_instr_map[] __attribute__((weak));
-extern const XRaySledEntry __stop_xray_instr_map[] __attribute__((weak));
-}
-
-using namespace __xray;
-
-// We initialize some global variables that pertain to specific sections of XRay
-// data structures in the binary. We do this for the current process using
-// /proc/curproc/map and make sure that we're able to get it. We signal failure
-// via a global atomic boolean to indicate whether we've initialized properly.
-//
-std::atomic<bool> XRayInitialized{false};
-
-// This should always be updated before XRayInitialized is updated.
-std::atomic<__xray::XRaySledMap> XRayInstrMap{};
-
-// __xray_init() will do the actual loading of the current process' memory map
-// and then proceed to look for the .xray_instr_map section/segment.
-void __xray_init() {
-  InitializeFlags();
-  if (__start_xray_instr_map == nullptr) {
-    Report("XRay instrumentation map missing. Not initializing XRay.\n");
-    return;
-  }
-
-  // Now initialize the XRayInstrMap global struct with the address of the
-  // entries, reinterpreted as an array of XRaySledEntry objects. We use the
-  // virtual pointer we have from the section to provide us the correct
-  // information.
-  __xray::XRaySledMap SledMap{};
-  SledMap.Sleds = __start_xray_instr_map;
-  SledMap.Entries = __stop_xray_instr_map - __start_xray_instr_map;
-  XRayInstrMap.store(SledMap, std::memory_order_release);
-  XRayInitialized.store(true, std::memory_order_release);
-
-  // FIXME: Check the flag/environment before patching.
-  if (flags()->patch_premain)
-    __xray_patch();
-}
-
-__attribute__((section(".preinit_array"),
-               used)) void (*__local_xray_preinit)(void) = __xray_init;