(histograms, num_histograms): New.
* hist.c (find_histogram, find_histogram_for_pc)
(read_histogram_header): New.
(s_lowpc, s_highpc, lowpc, highpc, hist_num_bins)
(hist_sample): Remove.
(hist_read_rec): Use the above, and handle multiple
histogram records with disjoint address ranges.
(hist_write_hist): Support several histogram records.
(scale_and_align_entries): Adjust for multiple histograms.
(hist_assign_samples_1): New.
(hist_assign_samples): Use the above.
(hist_clip_symbol_address): New.
* hist.h (hist_check_address)
(hist_clip_symbol_address): Declare.
* gmon_io.c (gmon_out_read, gmon_out_write): Adjust handling
of legacy format for multiple histogram changes.
* corefile.c (find_call): Check for core_text_space and
clip symbol address range here.
* vax.c (vax_find_call): Don't check for
core_text_space, or clip the symbol's address range here.
Use hist_check_address to check call's target address.
* sparc.c: Likewise.
* tahoe.c: Likewise.
* i386.c: Likewise.
* mips.c: Likewise. Also use core_text_sect->vma as the base
address for code accesses, just like other machine-specific
routines do.
* gprof.texi: Adjust for the new logic.
