Patch from Dan Nicolaescu

Patch from Dan Nicolaescu
* rtl.h (dump_rtx_statistics): Declare it.
* rtl.c (rtx_alloc_counts, rtx_alloc_sizes, rtvec_alloc_counts,
rtx_alloc_sizes): New static vars.
(rtx_alloc, rtvec_alloc): Update them.
(dump_rtx_statistics): New function.
* toplev.c (finalize): Call it.
* ggc-page.c (struct globals): Fix comments. Add new member
total_allocated_per_order.
(ggc_alloc): Keep track of the total allocated memory.
(ggc_print_statistics): Clarify message. Print total allocated
memory stats.
* configure.in (gather-detailed-mem-stats): New flag.
* configure: Regenerate.
* config.in: Regenerate.
* doc/install.texi (Configuration): Document
--enable-gather-detailed-mem-stats.

From-SVN: r74930