Big slowdown in 5.10 @_ parameter passing

Message-ID: <20080106191439.GF13935@bort.ca>

p4raw-id: //depot/perl@32891

diff --git a/op.c b/op.c
index a732aa4..af52a3a 100644 (file)
--- a/op.c
+++ b/op.c
@@ -3992,6 +3992,7 @@ Perl_newASSIGNOP(pTHX_ I32 flags, OP *left, I32 optype, OP *right)
        static const char no_list_state[] = "Initialization of state variables"
            " in list context currently forbidden";
        OP *curop;
+       bool maybe_common_vars = TRUE;
 
        PL_modcount = 0;
        /* Grandfathering $[ assignment here.  Bletch.*/
@@ -4009,6 +4010,65 @@ Perl_newASSIGNOP(pTHX_ I32 flags, OP *left, I32 optype, OP *right)
        o = newBINOP(OP_AASSIGN, flags, list(force_list(right)), curop);
        o->op_private = (U8)(0 | (flags >> 8));
 
+       if ((left->op_type == OP_LIST
+            || (left->op_type == OP_NULL && left->op_targ == OP_LIST)))
+       {
+           OP* lop = ((LISTOP*)left)->op_first;
+           maybe_common_vars = FALSE;
+           while (lop) {
+               if (lop->op_type == OP_PADSV ||
+                   lop->op_type == OP_PADAV ||
+                   lop->op_type == OP_PADHV ||
+                   lop->op_type == OP_PADANY) {
+                   if (!(lop->op_private & OPpLVAL_INTRO))
+                       maybe_common_vars = TRUE;
+
+                   if (lop->op_private & OPpPAD_STATE) {
+                       if (left->op_private & OPpLVAL_INTRO) {
+                           /* Each variable in state($a, $b, $c) = ... */
+                       }
+                       else {
+                           /* Each state variable in
+                              (state $a, my $b, our $c, $d, undef) = ... */
+                       }
+                       yyerror(no_list_state);
+                   } else {
+                       /* Each my variable in
+                          (state $a, my $b, our $c, $d, undef) = ... */
+                   }
+               } else if (lop->op_type == OP_UNDEF ||
+                          lop->op_type == OP_PUSHMARK) {
+                   /* undef may be interesting in
+                      (state $a, undef, state $c) */
+               } else {
+                   /* Other ops in the list. */
+                   maybe_common_vars = TRUE;
+               }
+               lop = lop->op_sibling;
+           }
+       }
+       else if ((left->op_private & OPpLVAL_INTRO)
+               && (   left->op_type == OP_PADSV
+                   || left->op_type == OP_PADAV
+                   || left->op_type == OP_PADHV
+                   || left->op_type == OP_PADANY))
+       {
+           maybe_common_vars = FALSE;
+           if (left->op_private & OPpPAD_STATE) {
+               /* All single variable list context state assignments, hence
+                  state ($a) = ...
+                  (state $a) = ...
+                  state @a = ...
+                  state (@a) = ...
+                  (state @a) = ...
+                  state %a = ...
+                  state (%a) = ...
+                  (state %a) = ...
+               */
+               yyerror(no_list_state);
+           }
+       }
+
        /* PL_generation sorcery:
         * an assignment like ($a,$b) = ($c,$d) is easier than
         * ($a,$b) = ($c,$a), since there is no need for temporary vars.
@@ -4023,7 +4083,7 @@ Perl_newASSIGNOP(pTHX_ I32 flags, OP *left, I32 optype, OP *right)
         * to store these values, evil chicanery is done with SvUVX().
         */
 
-       {
+       if (maybe_common_vars) {
            OP *lastop = o;
            PL_generation++;
            for (curop = LINKLIST(o); curop != o; curop = LINKLIST(curop)) {
@@ -4084,54 +4144,6 @@ Perl_newASSIGNOP(pTHX_ I32 flags, OP *left, I32 optype, OP *right)
                o->op_private |= OPpASSIGN_COMMON;
        }
 
-       if ((left->op_type == OP_LIST
-            || (left->op_type == OP_NULL && left->op_targ == OP_LIST))) {
-           OP* lop = ((LISTOP*)left)->op_first;
-           while (lop) {
-               if (lop->op_type == OP_PADSV ||
-                   lop->op_type == OP_PADAV ||
-                   lop->op_type == OP_PADHV ||
-                   lop->op_type == OP_PADANY) {
-                   if (lop->op_private & OPpPAD_STATE) {
-                       if (left->op_private & OPpLVAL_INTRO) {
-                           /* Each variable in state($a, $b, $c) = ... */
-                       }
-                       else {
-                           /* Each state variable in
-                              (state $a, my $b, our $c, $d, undef) = ... */
-                       }
-                       yyerror(no_list_state);
-                   } else {
-                       /* Each my variable in
-                          (state $a, my $b, our $c, $d, undef) = ... */
-                   }
-               } else {
-                   /* Other ops in the list. undef may be interesting in
-                      (state $a, undef, state $c) */
-               }
-               lop = lop->op_sibling;
-           }
-       }
-       else if (((left->op_private & (OPpLVAL_INTRO | OPpPAD_STATE))
-                   == (OPpLVAL_INTRO | OPpPAD_STATE))
-               && (   left->op_type == OP_PADSV
-                   || left->op_type == OP_PADAV
-                   || left->op_type == OP_PADHV
-                   || left->op_type == OP_PADANY))
-       {
-           /* All single variable list context state assignments, hence
-              state ($a) = ...
-              (state $a) = ...
-              state @a = ...
-              state (@a) = ...
-              (state @a) = ...
-              state %a = ...
-              state (%a) = ...
-              (state %a) = ...
-           */
-           yyerror(no_list_state);
-       }
-
        if (right && right->op_type == OP_SPLIT && !PL_madskills) {
            OP* tmpop = ((LISTOP*)right)->op_first;
            if (tmpop && (tmpop->op_type == OP_PUSHRE)) {