Move PERL_ASYNC_CHECK() from the runloop to control flow OPs.

For the typical code this gives a 5% speedup, and removes the cost of "safe
signals". Tight looping code will show less gains, but should never be slower.

Subtle bugs might remain - there might be constructions that enter the runloop
(where signals used to be dispatched) but don't contain any PERL_ASYNC_CHECK()
calls themselves.

1 files changed, 7 insertions, 0 deletions

diff --git a/pp_ctl.c b/pp_ctl.c
index bbb2d1587c..e766d7dde3 100644
--- a/pp_ctl.c
+++ b/pp_ctl.c
@@ -264,6 +264,9 @@ PP(pp_substcont)
     register REGEXP * const rx = cx->sb_rx;
     SV *nsv = NULL;
     REGEXP *old = PM_GETRE(pm);
+
+    PERL_ASYNC_CHECK();
+
     if(old != rx) {
 	if(old)
 	    ReREFCNT_dec(old);
@@ -1870,6 +1873,8 @@ PP(pp_dbstate)
     PL_stack_sp = PL_stack_base + cxstack[cxstack_ix].blk_oldsp;
     FREETMPS;
 
+    PERL_ASYNC_CHECK();
+
     if (PL_op->op_flags & OPf_SPECIAL /* breakpoint */
 	    || SvIV(PL_DBsingle) || SvIV(PL_DBsignal) || SvIV(PL_DBtrace))
     {
@@ -2652,6 +2657,8 @@ PP(pp_goto)
     else
 	label = cPVOP->op_pv;
 
+    PERL_ASYNC_CHECK();
+
     if (label && *label) {
 	OP *gotoprobe = NULL;
 	bool leaving_eval = FALSE;