Rearrange members of structures to reduce memory size on some

platforms. On LP64 structs stackinfo, refcounted_he, and magic shrink
by 8 bytes, struct yy_parser by 16.

p4raw-id: //depot/perl@30817

cop.h

@@ -748,11 +748,11 @@ L<perlcall>.
 struct stackinfo {
     AV *		si_stack;	/* stack for current runlevel */
     PERL_CONTEXT *	si_cxstack;	/* context stack for runlevel */
+    struct stackinfo *	si_prev;
+    struct stackinfo *	si_next;
     I32			si_cxix;	/* current context index */
     I32			si_cxmax;	/* maximum allocated index */
     I32			si_type;	/* type of runlevel */
-    struct stackinfo *	si_prev;
-    struct stackinfo *	si_next;
     I32			si_markoff;	/* offset where markstack begins for us.
 					 * currently used only with DEBUGGING,
 					 * but not #ifdef-ed for bincompat */

gv.h

@@ -10,14 +10,14 @@
 
 struct gp {
     SV *	gp_sv;		/* scalar value */
-    U32		gp_refcnt;	/* how many globs point to this? */
     struct io *	gp_io;		/* filehandle value */
-    CV *	gp_form;	/* format value */
-    AV *	gp_av;		/* array value */
-    HV *	gp_hv;		/* hash value */
-    GV *	gp_egv;		/* effective gv, if *glob */
     CV *	gp_cv;		/* subroutine value */
     U32		gp_cvgen;	/* generational validity of cached gv_cv */
+    U32		gp_refcnt;	/* how many globs point to this? */
+    HV *	gp_hv;		/* hash value */
+    AV *	gp_av;		/* array value */
+    CV *	gp_form;	/* format value */
+    GV *	gp_egv;		/* effective gv, if *glob */
     line_t	gp_line;	/* line first declared at (for -w) */
     HEK *	gp_file_hek;	/* file first declared in (for -w) */
 };

hv.h

@@ -403,13 +403,13 @@ struct refcounted_he {
 #else
     HEK                  *refcounted_he_hek;	/* hint key */
 #endif
-    U32	                  refcounted_he_refcnt;	/* reference count */
     union {
 	IV                refcounted_he_u_iv;
 	UV                refcounted_he_u_uv;
 	STRLEN            refcounted_he_u_len;
 	void		 *refcounted_he_u_ptr;	/* Might be useful in future */
     } refcounted_he_val;
+    U32	                  refcounted_he_refcnt;	/* reference count */
     /* First byte is flags. Then NUL-terminated value. Then for ithreads,
        non-NUL terminated key.  */
     char                  refcounted_he_data[1];

mg.h

@@ -30,9 +30,9 @@ struct magic {
     U16		mg_private;
     char	mg_type;
     U8		mg_flags;
+    I32		mg_len;
     SV*		mg_obj;
     char*	mg_ptr;
-    I32		mg_len;
 };
 
 #define MGf_TAINTEDDIR 1        /* PERL_MAGIC_envelem only */

parser.h

@@ -25,8 +25,8 @@ typedef struct yy_parser {
     /* parser state */
 
     struct yy_parser *old_parser; /* previous value of PL_parser */
-    int		    yychar;	/* The lookahead symbol.  */
     YYSTYPE	    yylval;	/* value of lookahead symbol, set by yylex() */
+    int		    yychar;	/* The lookahead symbol.  */
 
     /* Number of tokens to shift before error messages enabled.  */
     int		    yyerrstatus;
@@ -47,9 +47,9 @@ typedef struct yy_parser {
     int		lex_expect;	/* expect after determined token */
     I32		lex_formbrack;	/* bracket count at outer format level */
     OP		*lex_inpat;	/* in pattern $) and $| are special */
-    I32		lex_inwhat;	/* what kind of quoting are we in */
     OP		*lex_op;	/* extra info to pass back on op */
     SV		*lex_repl;	/* runtime replacement from s/// */
+    I32		lex_inwhat;	/* what kind of quoting are we in */
     I32		lex_starts;	/* how many interps done on level */
     SV		*lex_stuff;	/* runtime pattern from m// or s/// */
     I32		multi_start;	/* 1st line of multi-line string */

perl.h

@@ -5013,8 +5013,8 @@ struct am_table {
   U32 flags;
   U32 was_ok_sub;
   long was_ok_am;
-  CV* table[NofAMmeth];
   long fallback;
+  CV* table[NofAMmeth];
 };
 struct am_table_short {
   U32 flags;