From d9e6c738682c2012e5e7e87909941becd55cfbbd Mon Sep 17 00:00:00 2001 From: Dean Michael Berris Date: Thu, 13 Oct 2016 23:56:54 +0000 Subject: [compiler-rt][XRay] Support tail call sleds Summary: This change depends on D23986 which adds tail call-specific sleds. For now we treat them first as normal exits, and in the future leave room for implementing this as a different kind of log entry. The reason for deferring the change is so that we can keep the naive logging implementation more accurate without additional complexity for reading the log. The accuracy is gained in effectively interpreting call stacks like: A() B() C() Which when tail-call merged will end up not having any exit entries for A() nor B(), but effectively in turn can be reasoned about as: A() B() C() Although we lose the fact that A() had called B() then had called C() with the naive approach, a later iteration that adds the explicit tail call entries would be a change in the log format and thus necessitate a version change for the header. We can do this later to have a chance at releasing some tools (in D21987) that are able to handle the naive log format, then support higher version numbers of the log format too. Reviewers: echristo, kcc, rSerge, majnemer Subscribers: mehdi_amini, llvm-commits, dberris Differential Revision: https://reviews.llvm.org/D23988 git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@284178 91177308-0d34-0410-b5e6-96231b3b80d8 --- include/xray/xray_interface.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/xray') diff --git a/include/xray/xray_interface.h b/include/xray/xray_interface.h index 22f137d11..680fcfdd5 100644 --- a/include/xray/xray_interface.h +++ b/include/xray/xray_interface.h @@ -18,7 +18,7 @@ extern "C" { -enum XRayEntryType { ENTRY = 0, EXIT = 1 }; +enum XRayEntryType { ENTRY = 0, EXIT = 1, TAIL = 2 }; // Provide a function to invoke for when instrumentation points are hit. This is // a user-visible control surface that overrides the default implementation. The -- cgit v1.2.3