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.

1 files changed, 12 insertions, 12 deletions

diff --git a/vms/vms.c b/vms/vms.c
index a8e42c44bc..e20150db69 100644
--- a/vms/vms.c
+++ b/vms/vms.c
@@ -1421,7 +1421,7 @@ prime_env_iter(void)
     while (1) {
       char *cp1, *cp2, *key;
       unsigned long int sts, iosb[2], retlen, keylen;
-      register U32 hash;
+      U32 hash;
 
       sts = sys$qiow(0,chan,IO$_READVBLK,iosb,0,0,buf,mbxbufsiz,0,0,0,0);
       if (sts & 1) sts = iosb[0] & 0xffff;
@@ -8270,7 +8270,7 @@ static char *int_tovmsspec
    (const char *path, char *rslt, int dir_flag, int * utf8_flag) {
   char *dirend;
   char *lastdot;
-  register char *cp1;
+  char *cp1;
   const char *cp2;
   unsigned long int infront = 0, hasdir = 1;
   int rslt_len;
@@ -9705,7 +9705,7 @@ int
 Perl_trim_unixpath(pTHX_ char *fspec, const char *wildspec, int opts)
 {
   char *unixified, *unixwild, *tplate, *base, *end, *cp1, *cp2;
-  register int tmplen, reslen = 0, dirs = 0;
+  int tmplen, reslen = 0, dirs = 0;
 
   if (!wildspec || !fspec) return 0;
 
@@ -10359,9 +10359,9 @@ static char *
 setup_argstr(pTHX_ SV *really, SV **mark, SV **sp)
 {
   char *junk, *tmps = NULL;
-  register size_t cmdlen = 0;
+  size_t cmdlen = 0;
   size_t rlen;
-  register SV **idx;
+  SV **idx;
   STRLEN n_a;
 
   idx = mark;
@@ -10413,10 +10413,10 @@ setup_cmddsc(pTHX_ const char *incmd, int check_img, int *suggest_quote,
   struct dsc$descriptor_s *vmscmd;
   struct dsc$descriptor_s imgdsc = {0, DSC$K_DTYPE_T, DSC$K_CLASS_S, 0};
   unsigned long int cxt = 0, flags = 1, retsts = SS$_NORMAL;
-  register char *s, *rest, *cp, *wordbreak;
+  char *s, *rest, *cp, *wordbreak;
   char * cmd;
   int cmdlen;
-  register int isdcl;
+  int isdcl;
 
   vmscmd = (struct dsc$descriptor_s *)PerlMem_malloc(sizeof(struct dsc$descriptor_s));
   if (vmscmd == NULL) _ckvmssts_noperl(SS$_INSFMEM);
@@ -10569,7 +10569,7 @@ setup_cmddsc(pTHX_ const char *incmd, int check_img, int *suggest_quote,
       isdcl = 1;
       if (suggest_quote) *suggest_quote = 1;
   } else {
-    register char *filespec = strpbrk(s,":<[.;");
+    char *filespec = strpbrk(s,":<[.;");
     rest = wordbreak = strpbrk(s," \"\t/");
     if (!wordbreak) wordbreak = s + strlen(s);
     if (*s == '$') check_img = 0;
@@ -11060,10 +11060,10 @@ int my_fclose(FILE *fp) {
 int
 my_fwrite(const void *src, size_t itmsz, size_t nitm, FILE *dest)
 {
-  register char *cp, *end, *cpd;
+  char *cp, *end, *cpd;
   char *data;
-  register unsigned int fd = fileno(dest);
-  register unsigned int fdoff = fd / sizeof(unsigned int);
+  unsigned int fd = fileno(dest);
+  unsigned int fdoff = fd / sizeof(unsigned int);
   int retval;
   int bufsize = itmsz * nitm + 1;
 
@@ -11603,7 +11603,7 @@ int Perl_my_utime(pTHX_ const char *file, const struct utimbuf *utimes)
 
 #else /* __CRTL_VER < 70300000 */
 
-  register int i;
+  int i;
   int sts;
   long int bintime[2], len = 2, lowbit, unixtime,
            secscale = 10000000; /* seconds --> 100 ns intervals */