Omnibus removal of register declarations

This removes most register declarations in C code (and accompanying
documentation) in the Perl core.  Retained are those in the ext
directory, Configure, and those that are associated with assembly
language.

See:
http://stackoverflow.com/questions/314994/whats-a-good-example-of-register-variable-usage-in-c

which says, in part:

There is no good example of register usage when using modern compilers
(read: last 10+ years) because it almost never does any good and can do
some bad. When you use register, you are telling the compiler "I know
how to optimize my code better than you do" which is almost never the
case. One of three things can happen when you use register:

    The compiler ignores it, this is most likely. In this case the only
        harm is that you cannot take the address of the variable in the
        code.
    The compiler honors your request and as a result the code runs slower.
    The compiler honors your request and the code runs faster, this is the least likely scenario.

Even if one compiler produces better code when you use register, there
is no reason to believe another will do the same. If you have some
critical code that the compiler is not optimizing well enough your best
bet is probably to use assembler for that part anyway but of course do
the appropriate profiling to verify the generated code is really a
problem first.

6 files changed, 57 insertions, 57 deletions

diff --git a/x2p/a2p.c b/x2p/a2p.c
index 1a7a77851e..8d6e9cde57 100644
--- a/x2p/a2p.c
+++ b/x2p/a2p.c
@@ -2191,9 +2191,9 @@ EXTERN_C char *getenv(const char *);
 int
 yyparse(void)
 {
-    register int yym, yyn, yystate;
+    int yym, yyn, yystate;
 #if YYDEBUG
-    register const char *yys;
+    const char *yys;
 
     if ((yys = getenv("YYDEBUG")))
     {
diff --git a/x2p/a2py.c b/x2p/a2py.c
index f6944b9005..2f41ca86ec 100644
--- a/x2p/a2py.c
+++ b/x2p/a2py.c
@@ -61,7 +61,7 @@ usage()
 int
 main(register int argc, register const char **argv, register const char **env)
 {
-    register STR *str;
+    STR *str;
     int i;
     STR *tmpstr;
     /* char *namelist;    */
@@ -221,9 +221,9 @@ int idtype;
 int
 yylex(void)
 {
-    register char *s = bufptr;
-    register char *d;
-    register int tmp;
+    char *s = bufptr;
+    char *d;
+    int tmp;
 
   retry:
 #if YYDEBUG
@@ -828,7 +828,7 @@ yylex(void)
 char *
 scanpat(register char *s)
 {
-    register char *d;
+    char *d;
 
     switch (*s++) {
     case '/':
@@ -880,7 +880,7 @@ yyerror(const char *s)
 char *
 scannum(register char *s)
 {
-    register char *d;
+    char *d;
 
     switch (*s) {
     case '1': case '2': case '3': case '4': case '5':
@@ -1027,9 +1027,9 @@ int depth = 0;
 void
 dump(int branch)
 {
-    register int type;
-    register int len;
-    register int i;
+    int type;
+    int len;
+    int i;
 
     type = ops[branch].ival;
     len = type >> 8;
@@ -1067,8 +1067,8 @@ bl(int arg, int maybe)
 void
 fixup(STR *str)
 {
-    register char *s;
-    register char *t;
+    char *s;
+    char *t;
 
     for (s = str->str_ptr; *s; s++) {
 	if (*s == ';' && s[1] == ' ' && s[2] == '\n') {
@@ -1092,8 +1092,8 @@ fixup(STR *str)
 void
 putlines(STR *str)
 {
-    register char *d, *s, *t, *e;
-    register int pos, newpos;
+    char *d, *s, *t, *e;
+    int pos, newpos;
 
     d = tokenbuf;
     pos = 0;
@@ -1168,7 +1168,7 @@ putlines(STR *str)
 void
 putone(void)
 {
-    register char *t;
+    char *t;
 
     for (t = tokenbuf; *t; t++) {
 	*t &= 127;
diff --git a/x2p/hash.c b/x2p/hash.c
index 9cc50f8dba..1620175584 100644
--- a/x2p/hash.c
+++ b/x2p/hash.c
@@ -19,10 +19,10 @@ char *savestr(char *str);
 STR *
 hfetch(register HASH *tb, char *key)
 {
-    register char *s;
-    register int i;
-    register int hash;
-    register HENT *entry;
+    char *s;
+    int i;
+    int hash;
+    HENT *entry;
 
     if (!tb)
 	return NULL;
@@ -45,11 +45,11 @@ hfetch(register HASH *tb, char *key)
 bool
 hstore(register HASH *tb, char *key, STR *val)
 {
-    register char *s;
-    register int i;
-    register int hash;
-    register HENT *entry;
-    register HENT **oentry;
+    char *s;
+    int i;
+    int hash;
+    HENT *entry;
+    HENT **oentry;
 
     if (!tb)
 	return FALSE;
@@ -94,12 +94,12 @@ void
 hsplit(HASH *tb)
 {
     const int oldsize = tb->tbl_max + 1;
-    register int newsize = oldsize * 2;
-    register int i;
-    register HENT **a;
-    register HENT **b;
-    register HENT *entry;
-    register HENT **oentry;
+    int newsize = oldsize * 2;
+    int i;
+    HENT **a;
+    HENT **b;
+    HENT *entry;
+    HENT **oentry;
 
     a = (HENT**) saferealloc((char*)tb->tbl_array, newsize * sizeof(HENT*));
     memset(&a[oldsize], 0, oldsize * sizeof(HENT*)); /* zero second half */
@@ -130,7 +130,7 @@ hsplit(HASH *tb)
 HASH *
 hnew(void)
 {
-    register HASH *tb = (HASH*)safemalloc(sizeof(HASH));
+    HASH *tb = (HASH*)safemalloc(sizeof(HASH));
 
     tb->tbl_array = (HENT**) safemalloc(8 * sizeof(HENT*));
     tb->tbl_fill = 0;
diff --git a/x2p/str.c b/x2p/str.c
index d54d08818b..c10e974374 100644
--- a/x2p/str.c
+++ b/x2p/str.c
@@ -22,7 +22,7 @@ str_numset(register STR *str, double num)
 char *
 str_2ptr(register STR *str)
 {
-    register char *s;
+    char *s;
 
     if (!str)
 	return (char *)"";	/* probably safe - won't be written to */
@@ -69,7 +69,7 @@ str_nset(register STR *str, register const char *ptr, register int len)
 void
 str_set(register STR *str, register const char *ptr)
 {
-    register int len;
+    int len;
 
     if (!ptr)
 	ptr = "";
@@ -106,7 +106,7 @@ str_scat(STR *dstr, register STR *sstr)
 void
 str_cat(register STR *str, register const char *ptr)
 {
-    register int len;
+    int len;
 
     if (!ptr)
 	return;
@@ -123,7 +123,7 @@ str_cat(register STR *str, register const char *ptr)
 STR *
 str_new(int len)
 {
-    register STR *str;
+    STR *str;
     
     if (freestrroot) {
 	str = freestrroot;
@@ -173,10 +173,10 @@ str_gets(register STR *str, register FILE *fp)
 #if defined(USE_STDIO_PTR) && defined(STDIO_PTR_LVALUE) && defined(STDIO_CNT_LVALUE)
     /* Here is some breathtakingly efficient cheating */
 
-    register char *bp;		/* we're going to steal some values */
-    register int cnt;		/*  from the stdio struct and put EVERYTHING */
-    register STDCHAR *ptr;	/*   in the innermost loop into registers */
-    register char newline = '\n';	/* (assuming at least 6 registers) */
+    char *bp;		/* we're going to steal some values */
+    int cnt;		/*  from the stdio struct and put EVERYTHING */
+    STDCHAR *ptr;	/*   in the innermost loop into registers */
+    char newline = '\n';	/* (assuming at least 6 registers) */
     int i;
     int bpx;
 
@@ -252,7 +252,7 @@ thats_all_folks:
 STR *
 str_make(const char *s)
 {
-    register STR *str = str_new(0);
+    STR *str = str_new(0);
 
     str_set(str,s);
     return str;
diff --git a/x2p/util.c b/x2p/util.c
index 464dd8f5e9..da17c862df 100644
--- a/x2p/util.c
+++ b/x2p/util.c
@@ -121,8 +121,8 @@ cpy2(register char *to, register char *from, register int delim)
 char *
 instr(char *big, const char *little)
 {
-    register char *t, *x;
-    register const char *s;
+    char *t, *x;
+    const char *s;
 
     for (t = big; *t; t++) {
 	for (x=t,s=little; *s; x++,s++) {
@@ -142,7 +142,7 @@ instr(char *big, const char *little)
 char *
 savestr(const char *str)
 {
-    register char * const newaddr = (char *) safemalloc((MEM_SIZE)(strlen(str)+1));
+    char * const newaddr = (char *) safemalloc((MEM_SIZE)(strlen(str)+1));
 
     (void)strcpy(newaddr,str);
     return newaddr;
diff --git a/x2p/walk.c b/x2p/walk.c
index 03cc5944b5..a92808f432 100644
--- a/x2p/walk.c
+++ b/x2p/walk.c
@@ -42,11 +42,11 @@ char *instr(char *big, const char *little);
 STR *
 walk(int useval, int level, register int node, int *numericptr, int minprec)
 {
-    register int len;
-    register STR *str;
-    register int type;
-    register int i;
-    register STR *tmpstr;
+    int len;
+    STR *str;
+    int type;
+    int i;
+    STR *tmpstr;
     STR *tmp2str;
     STR *tmp3str;
     char *t;
@@ -1559,7 +1559,7 @@ tab(register STR *str, register int lvl)
 static void
 fixtab(register STR *str, register int lvl)
 {
-    register char *s;
+    char *s;
 
     /* strip trailing white space */
 
@@ -1577,7 +1577,7 @@ fixtab(register STR *str, register int lvl)
 static void
 addsemi(register STR *str)
 {
-    register char *s;
+    char *s;
 
     s = str->str_ptr+str->str_cur - 1;
     while (s >= str->str_ptr && (*s == ' ' || *s == '\t' || *s == '\n'))
@@ -1589,7 +1589,7 @@ addsemi(register STR *str)
 static void
 emit_split(register STR *str, int level)
 {
-    register int i;
+    int i;
 
     if (split_to_array)
 	str_cat(str,"@Fld");
@@ -1622,9 +1622,9 @@ emit_split(register STR *str, int level)
 int
 prewalk(int numit, int level, register int node, int *numericptr)
 {
-    register int len;
-    register int type;
-    register int i;
+    int len;
+    int type;
+    int i;
     int numarg;
     int numeric = FALSE;
     STR *tmpstr;
@@ -2039,8 +2039,8 @@ prewalk(int numit, int level, register int node, int *numericptr)
 static void
 numericize(register int node)
 {
-    register int len;
-    register int type;
+    int len;
+    int type;
     STR *tmpstr;
     STR *tmp2str;
     int numarg;