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
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
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
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
Dean Michael Berris