Bug 689488

Created attachment 3424 [details]
profile.txt

Customer supplied profile for gs8.60

Created attachment 3425 [details]
patch

This patch fixes the problem.

Please ignore comment #2 (the patch is for a different bug).

I attempted to find the revision responsible for the increase in processing time but my results were not 
definitive:

rev   run time (minutes:seconds)
6375  0:36
7004  0:36
7005  4:30
7158  4:34
7159  7:08
7187  7:18
7188  doesn't build
7189  8:56
7902  9:51
7903 10:48
8257 10:21

The change made in the rev. 7005 is the most significant factor.
Reverting this change speeds in the current version gives 7 times
speed improvement.

My testing with reverting the 7005 change is more significant:

8.60 stock: 9:32
8.60 without r7005: 0:33

There is no difference in the output.

Created attachment 3431 [details]
patch for gs8.60

The gstate is placed into the 2nd element of the implementation array
for a purpose - to simulate Adobe interpreters for CET compliance.
It is not used anywhere by Ghostscript.

We can place the same gstate (e.g. saved during the start-up) to all
Implementation arrays.

Created attachment 4006 [details]
patch

Reduce generation of garbage and the time spent on garbage collection by
placing gstate into the 2nd element of the patterm implementation array
in Adobe compatibility mode only. Ghostscript doesn't use this gstate
at all.

The patch is committed as a rev. 8727.
Regression testing shows no differences.

Profiling shows that most of the time is now goes into evaluation
of FunctionType 0. Perhaps, Leonardo can commend on the new profile.

  %   cumulative   self              self     total
 time   seconds   seconds    calls   s/call   s/call  name
 23.39     18.75    18.75   292343     0.00     0.00 
fn_Sd_1arg_linear_monotonic_rec
  8.97     25.94     7.19      564     0.01     0.14  interp
  6.86     31.44     5.50 22009901     0.00     0.00  fn_Sd_evaluate_general
  5.25     35.65     4.21 22009901     0.00     0.00  fn_interpolate_linear
  2.73     37.84     2.19 100041115     0.00     0.00  gx_unit_frac
  2.72     40.02     2.18  8251347     0.00     0.00  function_linearity
  2.11     41.71     1.69 12493371     0.00     0.00  is_dc_nearly_linear
  2.07     43.36     1.66  7294089     0.00     0.00  dstack_find_name_by_index
  2.00     44.97     1.61 96265099     0.00     0.00  fn_gets_8
  1.52     46.19     1.22 25715695     0.00     0.00  cmap_cmyk_direct
  1.47     47.37     1.18                             __divdi3
  1.42     48.51     1.14     3330     0.00     0.00  ht_tiles_reloc_ptrs
  1.24     49.50     0.99  2671943     0.00     0.00  gx_fill_trapezoid_ns_lc
  0.87     50.20     0.70 22202185     0.00     0.00  gx_restrict01_paint_3
  0.86     50.89     0.69   449342     0.00     0.00  gstate_clone
  0.80     51.53     0.64  2986374     0.00     0.00  names_ref
  0.79     52.16     0.63  6045239     0.00     0.00  get_color_index_cache_elem
  0.75     52.76     0.60  5252479     0.00     0.00  gc_trace
  0.71     53.32     0.57 96265099     0.00     0.00  data_source_access_string
  0.68     53.87     0.55   192081     0.00     0.00  fill_quadrangle
  0.68     54.41     0.55  9038352     0.00     0.00  dict_find
  0.62     54.91     0.50 25009847     0.00     0.00  gx_remap_DeviceCMYK
  0.61     55.40     0.49  4245114     0.00     0.00  gx_cspace_is_linear_in_line
  0.61     55.89     0.49  4161726     0.00     0.00  scan_token
  0.57     56.35     0.46 11725605     0.00     0.00  array_get
  0.56     56.80     0.45 22202185     0.00     0.00  gx_restrict01_paint_4
  0.55     57.24     0.44 25715659     0.00     0.00  fwd_map_cmyk_cs
  0.52     57.66     0.42  3995994     0.00     0.00 
gx_default_fill_linear_color_scanline
  0.50     58.06     0.40  4250542     0.00     0.00  init_gradient
  0.47     58.44     0.38  1108625     0.00     0.00  fn_Sd_1arg_linear_monotonic
  0.46     58.81     0.37  2894170     0.00     0.00  chunk_locate_ptr
  0.45     59.17     0.36 11285539     0.00     0.00  obj_eq
  0.43     59.51     0.35 12277041     0.00     0.00  igc_reloc_refs
  0.42     59.85     0.34  1528525     0.00     0.00  decompose_linear_color
  0.41     60.18     0.33  6045239     0.00     0.00  gs_cached_color_index
  0.41     60.51     0.33   510756     0.00     0.00  quadrangle_color_change
  0.40     60.83     0.32  1251747     0.00     0.00 
gx_cspace_is_linear_in_triangle
  0.39     61.14     0.31    23420     0.00     0.00  inflate_fast
  0.37     61.44     0.30 25715695     0.00     0.00  color_cmyk_to_rgb
  0.37     61.74     0.30    88276     0.00     0.00  gc_trace_chunk
  0.35     62.02     0.28  8081889     0.00     0.00  i_alloc_struct
  0.35     62.30     0.28  7244635     0.00     0.00  i_free_object
  0.35     62.58     0.28  5553158     0.00     0.00  refs_clear_reloc
  0.31     62.83     0.25  7147969     0.00     0.00  refs_clear_marks
  0.30     63.07     0.24    63007     0.00     0.00  gc_objects_compact
  0.29     63.30     0.24   192087     0.00     0.00  patch_fill
  0.27     63.52     0.22  1108625     0.00     0.00  get_scaled_range
  0.27     63.74     0.22   151283     0.00     0.00  gc_objects_clear_marks
  0.26     63.95     0.21 25715659     0.00     0.00 
gx_forward_get_color_mapping_procs
  0.25     64.15     0.20  2228571     0.00     0.00  gx_fill_trapezoid_ns_fd
  0.24     64.34     0.19   151283     0.00     0.00  gc_do_reloc
  0.24     64.53     0.19 13480160     0.00     0.00  zexec
  0.24     64.72     0.19 25715709     0.00     0.00  gx_default_rgb_map_rgb_color
  0.23     64.91     0.19   767372     0.00     0.00  triangle_by_4
  0.22     65.09     0.18  7290582     0.00     0.00  ztype

Rev. 8842 makes gs about 40% faster than v. 8.53 on the
given sample file.