re PR go/88202 (FAIL: runtime/pprof)

	PR go/88202
    runtime: in sigprof, skip to sigtrampgo if we don't find sigtramp

    Fixes https://gcc.gnu.org/PR88202

    Reviewed-on: https://go-review.googlesource.com/c/158218

From-SVN: r268057

diff --git a/gcc/go/gofrontend/MERGE b/gcc/go/gofrontend/MERGE
index 94604b2..99ec5cc 100644 (file)
--- a/gcc/go/gofrontend/MERGE
+++ b/gcc/go/gofrontend/MERGE
@@ -1,4 +1,4 @@
-d6576c83016d856217758c06d945bfc363ffb817
+d16e9181a760796802c067730bb030b92b63fb2c
 
 The first line of this file holds the git revision number of the last
 merge done from the gofrontend repository.

diff --git a/libgo/go/runtime/proc.go b/libgo/go/runtime/proc.go
index 655d0a9..80b04ab 100644 (file)
--- a/libgo/go/runtime/proc.go
+++ b/libgo/go/runtime/proc.go
@@ -3600,10 +3600,17 @@ func sigprof(pc uintptr, gp *g, mp *m) {
                // To ensure a sane profile, walk through the frames in
                // "stklocs" until we find the "runtime.sigtramp" frame, then
                // report only those frames below the frame one down from
-               // that. If for some reason "runtime.sigtramp" is not present,
-               // don't make any changes.
+               // that. On systems that don't split stack, "sigtramp" can
+               // do a sibling call to "sigtrampgo", so use "sigtrampgo"
+               // if we don't find "sigtramp". If for some reason
+               // neither "runtime.sigtramp" nor "runtime.sigtrampgo" is
+               // present, don't make any changes.
                framesToDiscard := 0
                for i := 0; i < n; i++ {
+                       if stklocs[i].function == "runtime.sigtrampgo" && i+2 < n {
+                               framesToDiscard = i + 2
+                               n -= framesToDiscard
+                       }
                        if stklocs[i].function == "runtime.sigtramp" && i+2 < n {
                                framesToDiscard = i + 2
                                n -= framesToDiscard