Commit Graph

9 Commits

Author SHA1 Message Date
Dean Michael Berris 5cc4632b5b [XRay][compiler-rt] Support patching/unpatching specific functions
Summary:
This change allows us to patch/unpatch specific functions using the
function ID. This is useful in cases where implementations might want to
do coverage-style, or more fine-grained control of which functions to
patch or un-patch at runtime.

Depends on D32693.

Reviewers: dblaikie, echristo, kpw

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D32695

llvm-svn: 302112
2017-05-04 04:59:20 +00:00
Dean Michael Berris 1dcec25487 [XRay][compiler-rt] Use sanitizer_common's atomic ops
Instead of std::atomic APIs for atomic operations, we instead use APIs
include with sanitizer_common. This allows us to, at runtime, not have
to depend on potentially dynamically provided implementations of these
atomic operations.

Fixes http://llvm.org/PR32274.

llvm-svn: 298833
2017-03-27 07:13:35 +00:00
Dean Michael Berris ea9042cf8f [XRay][compiler-rt][NFC] Turn ProudCase functions to humbleCase functions
Summary:
As pointed out in casual reading of the XRay codebase, that we had
some interesting named functions that didn't quite follow the LLVM coding
conventions.

Reviewers: chandlerc, dblaikie

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D29625

llvm-svn: 294373
2017-02-07 23:35:34 +00:00
Dean Michael Berris 4031e4b95d [XRay][compiler-rt] Disable XRay instrumentation of the XRay runtime.
Summary:
Adds a CMake check for whether the compiler used to build the XRay
library supports XRay-instrumentation. If the compiler we're using does
support the `-fxray-instrument` flag (i.e. recently-built Clang), we
define the XRAY_NEVER_INSTRUMENT macro that then makes sure that the
XRay runtime functions never get XRay-instrumented.

This prevents potential weirdness involved with building the XRay
library with a Clang that supports XRay-instrumentation, and is
attempting to XRay-instrument the build of compiler-rt.

Reviewers: majnemer, rSerge, echristo

Subscribers: mehdi_amini, llvm-commits, mgorny

Differential Revision: https://reviews.llvm.org/D26597

llvm-svn: 287068
2016-11-16 01:01:13 +00:00
Anna Zaks 691644f3ca [compiler-rt] Do not introduce __sanitizer namespace globally
The definitions in sanitizer_common may conflict with definitions from system headers because:

The runtime includes the system headers after the project headers (as per LLVM coding guidelines).
lib/sanitizer_common/sanitizer_internal_defs.h pollutes the namespace of everything defined after it, which is all/most of the sanitizer .h and .cc files and the included system headers with: using namespace __sanitizer; // NOLINT
This patch solves the problem by introducing the namespace only within the sanitizer namespaces as proposed by Dmitry.

Differential Revision: https://reviews.llvm.org/D21947

llvm-svn: 281657
2016-09-15 21:02:18 +00:00
Dean Michael Berris 17a586e6de [compiler-rt][XRay] Address follow-up comments to initial interface and initialisation code
This addresses some comments from D21612, which contains the following changes:

- Update __xray_patch() and __xray_unpatch() API documentation to not imply asynchrony.
- Introduce a scope cleanup mechanism to make sure we can roll-back changes to the XRayPatching global atomic.
- Introduce a few more comments for potential extension points for other platforms (for the implementation details of patching and un-patching).

Reviewers: eugenis, rnk, kcc, echristo, majnemer

Subscribers: llvm-commits, mehdi_amini

Differential Revision: https://reviews.llvm.org/D22911

llvm-svn: 277124
2016-07-29 07:11:58 +00:00
Dean Michael Berris 938c5031ab [compiler-rt][XRay] re-submitting r276117, with fixes for build breakage due to extraneous and missing dependencies and attempts to build on unsupported OSes
Summary:
This is a fixed-up version of D21612, to address failure identified post-commit.

Original commit description:

This patch implements the initialisation and patching routines for the XRay runtime, along with the necessary trampolines for function entry/exit handling. For now we only define the basic hooks for allowing an implementation to define a handler that gets run on function entry/exit. We expose a minimal API for controlling the behaviour of the runtime (patching, cleanup, and setting the handler to invoke when instrumenting).

Fixes include:
- Gating XRay build to only Linux x86_64 and with the right dependencies in case it is the only library being built
- Including <cstddef> to fix std::size_t issue

Reviewers: kcc, rnk, echristo

Subscribers: mehdi_amini, llvm-commits

Differential Revision: https://reviews.llvm.org/D22611

llvm-svn: 276251
2016-07-21 07:39:55 +00:00
Hans Wennborg ae4e6fe990 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
2016-07-20 21:37:38 +00:00
Dean Michael Berris e1c81d10d7 [compiler-rt] [XRay] Basic initialization and flag definition for XRay runtime
Summary:
This patch implements the initialisation and patching routines for the XRay runtime, along with the necessary trampolines for function entry/exit handling. For now we only define the basic hooks for allowing an implementation to define a handler that gets run on function entry/exit. We expose a minimal API for controlling the behaviour of the runtime (patching, cleanup, and setting the handler to invoke when instrumenting).

Depends on D19904

Reviewers: echristo, kcc, rnk

Subscribers: rnk, mehdi_amini, llvm-commits

Differential Revision: https://reviews.llvm.org/D21612

llvm-svn: 276117
2016-07-20 14:14:50 +00:00