From: Nicholas Clark <nick@ccl4.org>
Date: Thu, 28 Oct 2010 10:29:21 +0000 (+0100)
Subject: For B's OP accessors, encode the type and offset in the XS alias integer.
X-Git-Tag: accepted/trunk/20130322.191538~7084
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=086f9b42de23898bfafc9164a8ae344258663b3d;p=platform%2Fupstream%2Fperl.git

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
--- 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