For B's OP accessors, encode the type and offset in the XS alias integer.

This allows most of the code for simple structure lookups to be merged into
one XS routine. Start by merging U8 and PADOFFSET lookups in struct op with
the existing common OP* accessor code. This saves over 2K of object code on
this platform.

diff --git a/ext/B/B.xs b/ext/B/B.xs
index d706829..3faf596 100644 (file)
--- a/ext/B/B.xs
+++ b/ext/B/B.xs
@@ -831,24 +831,28 @@ threadsv_names()
 # endif
 #endif
 
-#define OP_targ(o)     o->op_targ
-#define OP_flags(o)    o->op_flags
-#define OP_private(o)  o->op_private
-
-#define OP_next_offset                 offsetof(struct op, op_next)
-#define OP_sibling_offset              offsetof(struct op, op_sibling)
-#define UNOP_first_offset              offsetof(struct unop, op_first)
-#define BINOP_last_offset              offsetof(struct binop, op_last)
-#define LOGOP_other_offset             offsetof(struct logop, op_other)
+#define OPp            0x00000
+#define PADOFFSETp     0x10000
+#define U8p            0x20000
+
+#define OP_next_ix             OPp | offsetof(struct op, op_next)
+#define OP_sibling_ix          OPp | offsetof(struct op, op_sibling)
+#define UNOP_first_ix          OPp | offsetof(struct unop, op_first)
+#define BINOP_last_ix          OPp | offsetof(struct binop, op_last)
+#define LOGOP_other_ix         OPp | offsetof(struct logop, op_other)
 #if PERL_VERSION >= 9
-#  define PMOP_pmreplstart_offset \
-       offsetof(struct pmop, op_pmstashstartu.op_pmreplstart)
+#  define PMOP_pmreplstart_ix \
+               OPp | offsetof(struct pmop, op_pmstashstartu.op_pmreplstart)
 #else
-#  define PMOP_pmreplstart_offset      offsetof(struct pmop, op_pmreplstart)
+#  define PMOP_pmreplstart_ix  OPp | offsetof(struct pmop, op_pmreplstart)
 #endif
-#define LOOP_redoop_offset             offsetof(struct loop, op_redoop)
-#define LOOP_nextop_offset             offsetof(struct loop, op_nextop)
-#define LOOP_lastop_offset             offsetof(struct loop, op_lastop)
+#define LOOP_redoop_ix         OPp | offsetof(struct loop, op_redoop)
+#define LOOP_nextop_ix         OPp | offsetof(struct loop, op_nextop)
+#define LOOP_lastop_ix         OPp | offsetof(struct loop, op_lastop)
+
+#define OP_targ_ix             PADOFFSETp | offsetof(struct op, op_targ)
+#define OP_flags_ix            U8p | offsetof(struct op, op_flags)
+#define OP_private_ix          U8p | offsetof(struct op, op_private)
 
 MODULE = B     PACKAGE = B::OP         PREFIX = OP_
 
@@ -863,26 +867,44 @@ OP_size(o)
 # The type checking code in B has always been identical for all OP types,
 # irrespective of whether the action is actually defined on that OP.
 # We should fix this
-B::OP
+void
 next(o)
        B::OP           o
     ALIAS:
-       B::OP::next = OP_next_offset
-       B::OP::sibling = OP_sibling_offset
-       B::UNOP::first = UNOP_first_offset
-       B::BINOP::last = BINOP_last_offset
-       B::LOGOP::other = LOGOP_other_offset
-       B::PMOP::pmreplstart = PMOP_pmreplstart_offset
-       B::LOOP::redoop = LOOP_redoop_offset
-       B::LOOP::nextop = LOOP_nextop_offset
-       B::LOOP::lastop = LOOP_lastop_offset
+       B::OP::next = OP_next_ix
+       B::OP::sibling = OP_sibling_ix
+       B::OP::targ = OP_targ_ix
+       B::OP::flags = OP_flags_ix
+       B::OP::private = OP_private_ix
+       B::UNOP::first = UNOP_first_ix
+       B::BINOP::last = BINOP_last_ix
+       B::LOGOP::other = LOGOP_other_ix
+       B::PMOP::pmreplstart = PMOP_pmreplstart_ix
+       B::LOOP::redoop = LOOP_redoop_ix
+       B::LOOP::nextop = LOOP_nextop_ix
+       B::LOOP::lastop = LOOP_lastop_ix
     PREINIT:
        char *ptr;
-    CODE:
-       ptr = ix + (char *)o;
-       RETVAL = *((OP **)ptr);
-    OUTPUT:
-       RETVAL
+       SV *ret;
+    PPCODE:
+       ptr = (ix & 0xFFFF) + (char *)o;
+       switch ((U8)(ix >> 16)) {
+       case (U8)(OPp >> 16):
+           {
+               OP *const o2 = *((OP **)ptr);
+               ret = sv_newmortal();
+               sv_setiv(newSVrv(ret, cc_opclassname(aTHX_ o2)), PTR2IV(o2));
+               break;
+           }
+       case (U8)(PADOFFSETp >> 16):
+           ret = sv_2mortal(newSVuv(*((PADOFFSET*)ptr)));
+           break;
+       case (U8)(U8p >> 16):
+           ret = sv_2mortal(newSVuv(*((U8*)ptr)));
+           break;
+       }
+       ST(0) = ret;
+       XSRETURN(1);
 
 char *
 OP_name(o)
@@ -907,10 +929,6 @@ OP_ppaddr(o)
        sv_catpvs(sv, "]");
        ST(0) = sv;
 
-PADOFFSET
-OP_targ(o)
-       B::OP           o
-
 #if PERL_VERSION >= 9
 #  These 3 are all bitfields, so we can't take their addresses.
 UV
@@ -953,14 +971,6 @@ OP_type(o)
 
 #endif
 
-U8
-OP_flags(o)
-       B::OP           o
-
-U8
-OP_private(o)
-       B::OP           o
-
 void
 OP_oplist(o)
        B::OP           o