Implement PPC0030: undef aware equality

MANIFEST

@@ -6365,6 +6365,7 @@ t/op/dor.t				See if defined-or (//) works
 t/op/dump.t				See if dump works.
 t/op/each.t				See if hash iterators work
 t/op/each_array.t			See if array iterators work
+t/op/equ.t				See if the equ operator works
 t/op/eval.t				See if eval operator works
 t/op/evalbytes.t			See if evalbytes operator works
 t/op/exec.t				See if exec, system and qx work

ext/Opcode/Opcode.pm

@@ -1,4 +1,4 @@
-package Opcode 1.71;
+package Opcode 1.72;
 
 use strict;
 
@@ -319,8 +319,9 @@ invert_opset function.
     nbit_xor nbit_or sbit_and sbit_xor sbit_or negate i_negate not
     complement ncomplement scomplement
 
-    lt i_lt gt i_gt le i_le ge i_ge eq i_eq ne i_ne ncmp i_ncmp
-    slt sgt sle sge seq sne scmp
+    lt i_lt gt i_gt le i_le ge i_ge eq i_eq ne i_ne
+    equ i_equ neu i_neu ncmp i_ncmp
+    slt sgt sle sge seq sne sequ sneu scmp
     isa
 
     substr substr_left vec stringify study pos length index

gv.c

@@ -625,15 +625,16 @@ S_maybe_add_coresub(pTHX_ HV * const stash, GV *gv,
     case KEY_catch   : case KEY_class   :
     case KEY_cmp     : case KEY_default : case KEY_defer :
     case KEY_do      : case KEY_dump   : case KEY_else  : case KEY_elsif  :
-    case KEY_eq     : case KEY_eval  : case KEY_field  :
+    case KEY_eq      : case KEY_equ     : case KEY_eval  : case KEY_field  :
     case KEY_finally:
     case KEY_for     : case KEY_foreach: case KEY_format: case KEY_ge     :
     case KEY_given   : case KEY_goto   : case KEY_grep  : case KEY_gt     :
     case KEY_if      : case KEY_isa    :
     case KEY_last   :
     case KEY_le      : case KEY_local  : case KEY_lt    : case KEY_m      :
     case KEY_map     : case KEY_method : case KEY_my    :
-    case KEY_ne   : case KEY_next : case KEY_no: case KEY_or: case KEY_our:
+    case KEY_ne      : case KEY_neu    : case KEY_next : case KEY_no:
+    case KEY_or      : case KEY_our    :
     case KEY_package: case KEY_print: case KEY_printf:
     case KEY_q    : case KEY_qq   : case KEY_qr     : case KEY_qw    :
     case KEY_qx   : case KEY_redo : case KEY_require: case KEY_return:
@@ -3368,7 +3369,8 @@ Perl_gv_handler(pTHX_ HV *stash, I32 id)
 /* Implement tryAMAGICun_MG macro.
    Do get magic, then see if the stack arg is overloaded and if so call it.
    Flags:
-        AMGf_numeric apply sv_2num to the stack arg.
+        AMGf_numeric      apply sv_2num to the stack arg.
+        AMGf_no_GETMAGIC  do not call SvGETMAGIC on arguments
 */
 
 bool
@@ -3380,7 +3382,8 @@ Perl_try_amagic_un(pTHX_ int method, int flags)
     SV* const arg = PL_stack_sp[0];
     bool is_rc = rpp_stack_is_rc();
 
-    SvGETMAGIC(arg);
+    if (LIKELY(!(flags & AMGf_no_GETMAGIC)))
+        SvGETMAGIC(arg);
 
     if (SvAMAGIC(arg) && (tmpsv = amagic_call(arg, &PL_sv_undef, method,
                                               AMGf_noright | AMGf_unary
@@ -3573,8 +3576,9 @@ Perl_amagic_applies(pTHX_ SV *sv, int method, int flags)
    Do get magic, then see if the two stack args are overloaded and if so
    call it.
    Flags:
-        AMGf_assign  op may be called as mutator (eg +=)
-        AMGf_numeric apply sv_2num to the stack arg.
+        AMGf_assign       op may be called as mutator (eg +=)
+        AMGf_numeric      apply sv_2num to the stack arg.
+        AMGf_no_GETMAGIC  do not call SvGETMAGIC on arguments
 */
 
 bool
@@ -3586,9 +3590,11 @@ Perl_try_amagic_bin(pTHX_ int method, int flags)
     SV* right = PL_stack_sp[0];
     bool is_rc = rpp_stack_is_rc();
 
-    SvGETMAGIC(left);
-    if (left != right)
-        SvGETMAGIC(right);
+    if (LIKELY(!(flags & AMGf_no_GETMAGIC))) {
+        SvGETMAGIC(left);
+        if (left != right)
+            SvGETMAGIC(right);
+    }
 
     if (SvAMAGIC(left) || SvAMAGIC(right)) {
         SV * tmpsv;