From: Nicholas Clark <nick@ccl4.org>
Date: Sat, 26 Jan 2008 21:55:51 +0000 (+0000)
Subject: The layout for struct block_loop under ithreads can be simplified.
X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=commitdiff_plain;h=e846cb9248fdbc78eb6a883f17c20c3785e7f2de;p=p5sagit%2Fp5-mst-13.2.git

The layout for struct block_loop under ithreads can be simplified.
Instead of wedging the pad offset into a void* iterdata, and always
storing PL_comppad even when it isn't used, instead do this:

PAD        *oldcomppad; /* Also used for the GV, if targoffset is 0 */
/* This is also accesible via cx->blk_loop.my_op->op_targ */
PADOFFSET  targoffset;

and store the GV pointer in oldcompad. Pointers to pointers seems
cleaner. This also allows us to eliminate the flag bit CXp_PADVAR.

p4raw-id: //depot/perl@33081
---

diff --git a/cop.h b/cop.h
index 4af6b8f..b79cc19 100644
--- a/cop.h
+++ b/cop.h
@@ -436,8 +436,9 @@ struct block_loop {
     /* (except for non_ithreads we need to modify next_op in pp_ctl.c, hence
 	why next_op is conditionally defined below.)  */
 #ifdef USE_ITHREADS
-    void *	iterdata;
-    PAD		*oldcomppad;
+    PAD		*oldcomppad; /* Also used for the GV, if targoffset is 0 */
+    /* This is also accesible via cx->blk_loop.my_op->op_targ */
+    PADOFFSET	targoffset;
 #else
     OP *	next_op;
     SV **	itervar;
@@ -460,18 +461,19 @@ struct block_loop {
 
 #ifdef USE_ITHREADS
 #  define CxITERVAR(c)							\
-	((c)->blk_loop.iterdata						\
-	 ? (CxPADLOOP(cx) 						\
-	    ? &CX_CURPAD_SV( (c)->blk_loop, 				\
-		    INT2PTR(PADOFFSET, (c)->blk_loop.iterdata))		\
-	    : &GvSV((GV*)(c)->blk_loop.iterdata))			\
+	((c)->blk_loop.oldcomppad					\
+	 ? (CxPADLOOP(c) 						\
+	    ? &CX_CURPAD_SV( (c)->blk_loop, (c)->blk_loop.targoffset )	\
+	    : &GvSV((GV*)(c)->blk_loop.oldcomppad))			\
 	 : (SV**)NULL)
-#  define CX_ITERDATA_SET(cx,idata)					\
-	CX_CURPAD_SAVE(cx->blk_loop);					\
-	cx->blk_loop.iterdata = (idata);
+#  define CX_ITERDATA_SET(cx,idata,o)					\
+	if ((cx->blk_loop.targoffset = (o)))				\
+	    CX_CURPAD_SAVE(cx->blk_loop);				\
+	else								\
+	    cx->blk_loop.oldcomppad = (idata);
 #else
 #  define CxITERVAR(c)		((c)->blk_loop.itervar)
-#  define CX_ITERDATA_SET(cx,ivar)					\
+#  define CX_ITERDATA_SET(cx,ivar,o)					\
 	cx->blk_loop.itervar = (SV**)(ivar);
 #endif
 #define CxLABEL(c)	(0 + (c)->blk_oldcop->cop_label)
@@ -492,15 +494,15 @@ struct block_loop {
 	PUSHLOOP_OP_NEXT;						\
 	cx->blk_loop.state_u.ary.ary = NULL;				\
 	cx->blk_loop.state_u.ary.ix = 0;				\
-	CX_ITERDATA_SET(cx,NULL);
+	CX_ITERDATA_SET(cx, NULL, 0);
 
-#define PUSHLOOP_FOR(cx, dat, s)					\
+#define PUSHLOOP_FOR(cx, dat, s, offset)				\
 	cx->blk_loop.resetsp = s - PL_stack_base;			\
 	cx->blk_loop.my_op = cLOOP;					\
 	PUSHLOOP_OP_NEXT;						\
 	cx->blk_loop.state_u.ary.ary = NULL;				\
 	cx->blk_loop.state_u.ary.ix = 0;				\
-	CX_ITERDATA_SET(cx,dat);
+	CX_ITERDATA_SET(cx, dat, offset);
 
 #define POPLOOP(cx)							\
 	if (CxTYPE(cx) == CXt_LOOP_LAZYSV) {				\
@@ -680,10 +682,9 @@ struct context {
 /* private flags for CXt_LOOP */
 #define CXp_FOR_DEF	0x10	/* foreach using $_ */
 #ifdef USE_ITHREADS
-#  define CXp_PADVAR	0x20	/* itervar lives on pad, iterdata has pad
-				   offset; if not set, iterdata holds GV* */
-#  define CxPADLOOP(c)	(CxTYPE_is_LOOP(c) && ((c)->cx_type & (CXp_PADVAR)))
+#  define CxPADLOOP(c)	((c)->blk_loop.targoffset)
 #endif
+
 /* private flags for CXt_SUBST */
 #define CXp_ONCE	0x10	/* What was sbu_once in struct subst */
 
diff --git a/pp_ctl.c b/pp_ctl.c
index 9c6e2b1..87e2d40 100644
--- a/pp_ctl.c
+++ b/pp_ctl.c
@@ -1837,7 +1837,7 @@ PP(pp_enteriter)
     SV **svp;
     U8 cxtype = CXt_LOOP_FOR;
 #ifdef USE_ITHREADS
-    void *iterdata;
+    PAD *iterdata;
 #endif
 
     ENTER;
@@ -1853,8 +1853,7 @@ PP(pp_enteriter)
 #ifndef USE_ITHREADS
 	svp = &PAD_SVl(PL_op->op_targ);		/* "my" variable */
 #else
-	iterdata = INT2PTR(void*, PL_op->op_targ);
-	cxtype |= CXp_PADVAR;
+	iterdata = NULL;
 #endif
     }
     else {
@@ -1863,7 +1862,7 @@ PP(pp_enteriter)
 	SAVEGENERICSV(*svp);
 	*svp = newSV(0);
 #ifdef USE_ITHREADS
-	iterdata = (void*)gv;
+	iterdata = (PAD*)gv;
 #endif
     }
 
@@ -1874,9 +1873,9 @@ PP(pp_enteriter)
 
     PUSHBLOCK(cx, cxtype, SP);
 #ifdef USE_ITHREADS
-    PUSHLOOP_FOR(cx, iterdata, MARK);
+    PUSHLOOP_FOR(cx, iterdata, MARK, PL_op->op_targ);
 #else
-    PUSHLOOP_FOR(cx, svp, MARK);
+    PUSHLOOP_FOR(cx, svp, MARK, /*Not used*/);
 #endif
     if (PL_op->op_flags & OPf_STACKED) {
 	SV *maybe_ary = POPs;
diff --git a/sv.c b/sv.c
index 6d60eeb..d30f077 100644
--- a/sv.c
+++ b/sv.c
@@ -10557,13 +10557,14 @@ Perl_cx_dup(pTHX_ PERL_CONTEXT *cxs, I32 ix, I32 max, CLONE_PARAMS* param)
 		    = av_dup_inc(ncx->blk_loop.state_u.ary.ary, param);
 	    case CXt_LOOP_LAZYIV:
 	    case CXt_LOOP_PLAIN:
-		ncx->blk_loop.iterdata	= (CxPADLOOP(ncx)
-					   ? ncx->blk_loop.iterdata
-					   : gv_dup((GV*)ncx->blk_loop.iterdata,
-						    param));
-		ncx->blk_loop.oldcomppad
-		    = (PAD*)ptr_table_fetch(PL_ptr_table,
-					    ncx->blk_loop.oldcomppad);
+		if (CxPADLOOP(ncx)) {
+		    ncx->blk_loop.oldcomppad
+			= (PAD*)ptr_table_fetch(PL_ptr_table,
+						ncx->blk_loop.oldcomppad);
+		} else {
+		    ncx->blk_loop.oldcomppad
+			= (PAD*)gv_dup((GV*)ncx->blk_loop.oldcomppad, param);
+		}
 		break;
 	    case CXt_FORMAT:
 		ncx->blk_format.cv	= cv_dup(ncx->blk_format.cv, param);