[XRay][compiler-rt] Support string-based config for FDR mode

Summary:
In this chage we add support for the string-based configuration
mechanism for configuring FDR mode.

We deprecate most of the `xray_fdr_log_*` flags that are set with the
`XRAY_OPTIONS` environment variable. Instead we make the FDR
implementation take defaults from the `XRAY_FDR_OPTIONS` environment
variable, and use the flags defined in `xray_fdr_flags.{h,cc,inc}` for
the options we support.

This change addresses http://llvm.org/PR36790.

Depends on D46173.

Reviewers: eizan, pelikan, kpw, echristo

Subscribers: llvm-commits, mgorny

Differential Revision: https://reviews.llvm.org/D46174

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@331506 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 48 insertions, 0 deletions

diff --git a/lib/xray/xray_fdr_flags.cc b/lib/xray/xray_fdr_flags.cc
new file mode 100644
index 000000000..a14851b1b
--- /dev/null
+++ b/lib/xray/xray_fdr_flags.cc
@@ -0,0 +1,48 @@
+//===-- xray_fdr_flags.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 FDR flag parsing logic.
+//===----------------------------------------------------------------------===//
+
+#include "xray_fdr_flags.h"
+#include "sanitizer_common/sanitizer_common.h"
+#include "sanitizer_common/sanitizer_flag_parser.h"
+#include "sanitizer_common/sanitizer_libc.h"
+#include "xray_defs.h"
+
+using namespace __sanitizer;
+
+namespace __xray {
+
+FDRFlags xray_fdr_flags_dont_use_directly; // use via fdrFlags().
+
+void FDRFlags::setDefaults() XRAY_NEVER_INSTRUMENT {
+#define XRAY_FLAG(Type, Name, DefaultValue, Description) Name = DefaultValue;
+#include "xray_fdr_flags.inc"
+#undef XRAY_FLAG
+}
+
+void registerXRayFDRFlags(FlagParser *P, FDRFlags *F) XRAY_NEVER_INSTRUMENT {
+#define XRAY_FLAG(Type, Name, DefaultValue, Description)                       \
+  RegisterFlag(P, #Name, Description, &F->Name);
+#include "xray_fdr_flags.inc"
+#undef XRAY_FLAG
+}
+
+const char *useCompilerDefinedFDRFlags() XRAY_NEVER_INSTRUMENT {
+#ifdef XRAY_FDR_OPTIONS
+  return SANITIZER_STRINGIFY(XRAY_FDR_OPTIONS);
+#else
+  return "";
+#endif
+}
+
+} // namespace __xray