RFR: 8171855: Move package name transformations during module bootstrap into native code

[Peter Levart]

Hi Claes,

On 01/06/2017 03:36 AM, Claes Redestad wrote:
>
> New webrevs:
> http://cr.openjdk.java.net/~redestad/8171855/hotspot.04/
> http://cr.openjdk.java.net/~redestad/8171855/jdk.04/

In Module.c, it seems you applied the "techinique" of conditional 
allocation (lines 49...57), but forgot to remove the old code (58...62):

   49     if (len >= buf_size) {
   50         utf_str = malloc(len + 1);
   51         if (utf_str == NULL) {
   52             JNU_ThrowOutOfMemoryError(env, NULL);
   53             return NULL;
   54         }
   55     } else {
   56         utf_str = buf;
   57     }
   58     utf_str = malloc(len + 1);
   59     if (utf_str == NULL) {
   60         JNU_ThrowOutOfMemoryError(env, NULL);
   61         return NULL;
   62     }

Also, in line 84, you allocate pkgs array only when num_packages != 0:

   84     if (num_packages != 0 && (pkgs = calloc(num_packages, 
sizeof(char*))) == NULL) {

...but you free it unconditionally (does free(NULL) work as no-op?):

  110     free(pkgs);


In multiple methods of Module.c, you repeatedly use the following idiom:

  131     pkg_name = GetInternalPackageName(env, pkg, buf, 
(jsize)sizeof(buf));
  132     if (pkg_name == NULL) {
  133         JNU_ThrowOutOfMemoryError(env, NULL);
  134     } else {

...but there's no need to call JNU_ThrowOutOfMemoryError if 
GetInternalPackageName returns NULL since GetInternalPackageName already 
does it.


Otherwise the jdk part looks good.


Regards, Peter

>
> In addition to fixing comments I couldn't resist applying the technique
> used in Class.c to get rid of some mallocs in places where we can use a
> stack allocated char buf[128] instead, which seems to have a tiny, but
> measurable effect.
>
> Thanks!
>
> /Claes