Add SS_ADD_* macros and replace most SSPUSH* uses

The current idiom for adding an entry to the savestack is

    SSCHECK(3);
    SSPUSHINT(...);
    SSPUSHPTR(...);
    SSPUSHUV(SAVEt_...);

Replace this with a new idiom:

    {
        dSS_ADD;
        SS_ADD_INT(...);
        SS_ADD_PTR(...);
        SS_ADD_UV(SAVEt_...);
        SS_ADD_END(3);
    }

This is designed to be more efficient.

First, it defines some local vars, and defers updating PL_savestack_ix
to the end.

Second, it performs the 'is there space on the stack' check *after*
pushing. Doing the check last means that values in registers will have
been pushed and no longer needed, so don't need saving around the call to
grow. Also, tail-call elimination of the grow() can be done. These changes
reduce the code of something like save_pushptrptr() to half its former
size.

Of course, doing the size check *after* pushing means we must always
ensure there are SS_MAXPUSH free slots on the savestack */

1 files changed, 5 insertions, 2 deletions

diff --git a/pp_hot.c b/pp_hot.c
index 333c593c74..599b75927f 100644
--- a/pp_hot.c
+++ b/pp_hot.c
@@ -376,8 +376,11 @@ PP(pp_padrange)
                     | SAVEt_CLEARPADRANGE);
         assert(OPpPADRANGE_COUNTMASK + 1 == (1 <<OPpPADRANGE_COUNTSHIFT));
         assert((payload >> (OPpPADRANGE_COUNTSHIFT+SAVE_TIGHT_SHIFT)) == base);
-        SSCHECK(1);
-        SSPUSHUV(payload);
+        {
+            dSS_ADD;
+            SS_ADD_UV(payload);
+            SS_ADD_END(1);
+        }
 
         for (i = 0; i <count; i++)
             SvPADSTALE_off(*svp++); /* mark lexical as active */