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From: Xinliang David Li <davidxl@google.com>
To: Richard Guenther <richard.guenther@gmail.com>
Cc: GCC Patches <gcc-patches@gcc.gnu.org>
Subject: Re: -fdump-passes -fenable-xxx=func_name_list
Date: Thu, 02 Jun 2011 07:13:00 -0000	[thread overview]
Message-ID: <BANLkTimKpnPxF7iFWq7D01U-KZV0RL9Lew@mail.gmail.com> (raw)
In-Reply-To: <BANLkTi=y6cr4auzTps9eakr0Uo8X3zxHennB8cCENh8SdFP+mg@mail.gmail.com>

[-- Attachment #1: Type: text/plain, Size: 3386 bytes --]

This is the version of the patch that walks through pass lists.

Ok with this one?

David

On Wed, Jun 1, 2011 at 12:45 PM, Xinliang David Li <davidxl@google.com> wrote:
> On Wed, Jun 1, 2011 at 12:29 PM, Richard Guenther
> <richard.guenther@gmail.com> wrote:
>> On Wed, Jun 1, 2011 at 6:16 PM, Xinliang David Li <davidxl@google.com> wrote:
>>> On Wed, Jun 1, 2011 at 1:51 AM, Richard Guenther
>>> <richard.guenther@gmail.com> wrote:
>>>> On Wed, Jun 1, 2011 at 1:34 AM, Xinliang David Li <davidxl@google.com> wrote:
>>>>> The following patch implements the a new option that dumps gcc PASS
>>>>> configuration. The sample output is attached.  There is one
>>>>> limitation: some placeholder passes that are named with '*xxx' are
>>>>> note registered thus they are not listed. They are not important as
>>>>> they can not be turned on/off anyway.
>>>>>
>>>>> The patch also enhanced -fenable-xxx and -fdisable-xx to allow a list
>>>>> of function assembler names to be specified.
>>>>>
>>>>> Ok for trunk?
>>>>
>>>> Please split the patch.
>>>>
>>>> I'm not too happy how you dump the pass configuration.  Why not simply,
>>>> at a _single_ place, walk the pass tree?  Instead of doing pieces of it
>>>> at pass execution time when it's not already dumped - that really looks
>>>> gross.
>>>
>>> Yes, that was the original plan -- but it has problems
>>> 1) the dumper needs to know the root pass lists -- which can change
>>> frequently -- it can be a long term maintanance burden;
>>> 2) the centralized dumper needs to be done after option processing
>>> 3) not sure if gate functions have any side effects or have dependencies on cfun
>>>
>>> The proposed solutions IMHO is not that intrusive -- just three hooks
>>> to do the dumping and tracking indentation.
>>
>> Well, if you have a CU that is empty or optimized to nothing at some point
>> you will not get a complete pass list.  I suppose optimize attributes might
>> also confuse output.  Your solution might not be that intrusive
>> but it is still ugly.  I don't see 1) as an issue, for 2) you can just call the
>> dumping from toplev_main before calling do_compile (), 3) gate functions
>> shouldn't have side-effects, but as they could gate on optimize_for_speed ()
>> your option summary output will be bogus anyway.
>>
>> So - what is the output intended for if it isn't reliable?
>
> This needs to be cleaned up at some point -- the gate function should
> behave the same for all functions and per-function decisions need to
> be pushed down to the executor body.  I will try to rework the patch
> as you suggested to see if there are problems.
>
> David
>
>
>>
>> Richard.
>>
>>>>
>>>> The documentation should also link this option to the -fenable/disable
>>>> options as obviously the pass names in that dump are those to be
>>>> used for those flags (and not readily available anywhere else).
>>>
>>> Ok.
>>>
>>>>
>>>> I also think that it would be way more useful to note in the individual
>>>> dump files the functions (at the place they would usually appear) that
>>>> have the pass explicitly enabled/disabled.
>>>
>>> Ok -- for ipa passes or tree/rtl passes where all functions are
>>> explicitly disabled.
>>>
>>> Thanks,
>>>
>>> David
>>>
>>>>
>>>> Richard.
>>>>
>>>>> Thanks,
>>>>>
>>>>> David
>>>>>
>>>>
>>>
>>
>

[-- Attachment #2: dump-pass3.p --]
[-- Type: application/octet-stream, Size: 7243 bytes --]

Index: doc/invoke.texi
===================================================================
--- doc/invoke.texi	(revision 174550)
+++ doc/invoke.texi	(working copy)
@@ -291,6 +291,7 @@ Objective-C and Objective-C++ Dialects}.
 -fdump-translation-unit@r{[}-@var{n}@r{]} @gol
 -fdump-class-hierarchy@r{[}-@var{n}@r{]} @gol
 -fdump-ipa-all -fdump-ipa-cgraph -fdump-ipa-inline @gol
+-fdump-passes @gol
 -fdump-statistics @gol
 -fdump-tree-all @gol
 -fdump-tree-original@r{[}-@var{n}@r{]}  @gol
@@ -5060,7 +5061,8 @@ seperated list of function ranges.  Each
 The range is inclusive in both ends.  If the range is trivial, the number pair can be
 simplified a a single number.  If the function's cgraph node's @var{uid} is falling
 within one of the specified ranges, the @var{pass} is disabled for that function.
-The @var{uid} is shown in the function header of a dump file.
+The @var{uid} is shown in the function header of a dump file, and pass names can be
+dumped by using option @option{-fdump-passes}.
 
 @item -fdisable-tree-@var{pass}
 @item -fdisable-tree-@var{pass}=@var{range-list}
@@ -5483,6 +5485,11 @@ Dump after function inlining.
 
 @end table
 
+@item -fdump-passes
+@opindex fdump-passes
+Dump the list of optimization passes that are turned on and off by
+the current command line options.
+
 @item -fdump-statistics-@var{option}
 @opindex fdump-statistics
 Enable and control dumping of pass statistics in a separate file.  The
Index: tree-pass.h
===================================================================
--- tree-pass.h	(revision 174550)
+++ tree-pass.h	(working copy)
@@ -639,5 +639,6 @@ extern void do_per_function_toporder (vo
 
 extern void disable_pass (const char *);
 extern void enable_pass (const char *);
+extern void dump_passes (void);
 
 #endif /* GCC_TREE_PASS_H */
Index: cgraphunit.c
===================================================================
--- cgraphunit.c	(revision 174550)
+++ cgraphunit.c	(working copy)
@@ -1112,6 +1112,9 @@ cgraph_finalize_compilation_unit (void)
       fflush (stderr);
     }
 
+  if (flag_dump_passes)
+    dump_passes ();
+
   /* Gimplify and lower all functions, compute reachability and
      remove unreachable nodes.  */
   cgraph_analyze_functions ();
Index: common.opt
===================================================================
--- common.opt	(revision 174550)
+++ common.opt	(working copy)
@@ -1012,6 +1012,10 @@ fdump-noaddr
 Common Report Var(flag_dump_noaddr)
 Suppress output of addresses in debugging dumps
 
+fdump-passes
+Common Var(flag_dump_passes) Init(0)
+Dump optimization passes
+
 fdump-unnumbered
 Common Report Var(flag_dump_unnumbered)
 Suppress output of instruction numbers, line number notes and addresses in debugging dumps
Index: passes.c
===================================================================
--- passes.c	(revision 174550)
+++ passes.c	(working copy)
@@ -478,7 +478,7 @@ passr_eq (const void *p1, const void *p2
   return !strcmp (s1->unique_name, s2->unique_name);
 }
 
-static htab_t pass_name_tab = NULL;
+static htab_t name_to_pass_map = NULL;
 
 /* Register PASS with NAME.  */
 
@@ -488,11 +488,11 @@ register_pass_name (struct opt_pass *pas
   struct pass_registry **slot;
   struct pass_registry pr;
 
-  if (!pass_name_tab)
-    pass_name_tab = htab_create (256, passr_hash, passr_eq, NULL);
+  if (!name_to_pass_map)
+    name_to_pass_map = htab_create (256, passr_hash, passr_eq, NULL);
 
   pr.unique_name = name;
-  slot = (struct pass_registry **) htab_find_slot (pass_name_tab, &pr, INSERT);
+  slot = (struct pass_registry **) htab_find_slot (name_to_pass_map, &pr, INSERT);
   if (!*slot)
     {
       struct pass_registry *new_pr;
@@ -506,6 +506,127 @@ register_pass_name (struct opt_pass *pas
     return; /* Ignore plugin passes.  */
 }
 
+/* Map from pass id to canonicalized pass name.  */
+
+typedef const char *char_ptr;
+DEF_VEC_P(char_ptr);
+DEF_VEC_ALLOC_P(char_ptr, heap);
+static VEC(char_ptr, heap) *pass_tab = NULL;
+
+/* Callback function for traversing NAME_TO_PASS_MAP.  */
+
+static int
+pass_traverse (void **slot, void *data ATTRIBUTE_UNUSED)
+{
+  struct pass_registry **p = (struct pass_registry **)slot;
+  struct opt_pass *pass = (*p)->pass;
+
+  gcc_assert (pass->static_pass_number > 0);
+  gcc_assert (pass_tab);
+
+  VEC_replace (char_ptr, pass_tab, pass->static_pass_number,
+               (*p)->unique_name);
+
+  return 1;
+}
+
+/* The function traverses NAME_TO_PASS_MAP and creates a pass info
+   table for dumping purpose.  */
+
+static void
+create_pass_tab (void)
+{
+  if (!flag_dump_passes)
+    return;
+
+  VEC_safe_grow_cleared (char_ptr, heap,
+                         pass_tab, passes_by_id_size + 1);
+  htab_traverse (name_to_pass_map, pass_traverse, NULL);
+}
+
+static bool override_gate_status (struct opt_pass *, tree, bool);
+
+/* Dump the instantiated name for PASS. IS_ON indicates if PASS
+   is turned on or not.  */
+
+static void
+dump_one_pass (struct opt_pass *pass, int pass_indent)
+{
+  int indent = 3 * pass_indent;
+  const char *pn;
+  bool is_on, is_really_on;
+
+  is_on = (pass->gate == NULL) ? true : pass->gate();
+  is_really_on = override_gate_status (pass, current_function_decl, is_on);
+
+  if (pass->static_pass_number <= 0)
+    pn = pass->name;
+  else
+    pn = VEC_index (char_ptr, pass_tab, pass->static_pass_number);
+
+  fprintf (stderr, "%*s%-40s%*s:%s%s\n", indent, " ", pn,
+           (15 - indent < 0 ? 0 : 15 - indent), " ",
+           is_on ? "  ON" : "  OFF",
+           ((!is_on) == (!is_really_on) ? ""
+            : (is_really_on ? " (FORCED_ON)" : " (FORCED_OFF)")));
+}
+
+/* Dump pass list PASS with indentation INDENT.  */
+
+static void
+dump_pass_list (struct opt_pass *pass, int indent)
+{
+  do
+    {
+      dump_one_pass (pass, indent);
+      if (pass->sub)
+        dump_pass_list (pass->sub, indent + 1);
+      pass = pass->next;
+    }
+  while (pass);
+}
+
+/* Dump all optimization passes.  */
+
+void
+dump_passes (void)
+{
+  struct cgraph_node *n, *node = NULL;
+  tree save_fndecl = current_function_decl;
+
+  fprintf (stderr, "MAX_UID = %d\n", cgraph_max_uid);
+
+  create_pass_tab();
+  gcc_assert (pass_tab);
+
+  n = cgraph_nodes;
+  while (n)
+    {
+      if (DECL_STRUCT_FUNCTION (n->decl))
+        {
+          node = n;
+          break;
+        }
+      n = n->next;
+    }
+
+  if (!node)
+    return;
+
+  push_cfun (DECL_STRUCT_FUNCTION (node->decl));
+  current_function_decl = node->decl;
+
+  dump_pass_list (all_lowering_passes, 1);
+  dump_pass_list (all_small_ipa_passes, 1);
+  dump_pass_list (all_regular_ipa_passes, 1);
+  dump_pass_list (all_lto_gen_passes, 1);
+  dump_pass_list (all_passes, 1);
+
+  pop_cfun ();
+  current_function_decl = save_fndecl;
+}
+
+
 /* Returns the pass with NAME.  */
 
 static struct opt_pass *
@@ -513,9 +634,9 @@ get_pass_by_name (const char *name)
 {
   struct pass_registry **slot, pr;
 
-  gcc_assert (pass_name_tab);
+  gcc_assert (name_to_pass_map);
   pr.unique_name = name;
-  slot = (struct pass_registry **) htab_find_slot (pass_name_tab,
+  slot = (struct pass_registry **) htab_find_slot (name_to_pass_map,
                                                    &pr, NO_INSERT);
 
   if (!slot || !*slot)

[-- Attachment #3: out --]
[-- Type: application/octet-stream, Size: 14902 bytes --]

cc1: note: enable pass tree-unswitch for functions in the range of [0, 4294967295]
cc1: note: disable pass ipa-inline for functions in the range of [0, 4294967295]
MAX_UID = 4
   *warn_unused_result                                 :  ON
   *diagnose_omp_blocks                                :  OFF
   tree-mudflap1                                       :  OFF
   tree-omplower                                       :  ON
   tree-lower                                          :  ON
   tree-ehopt                                          :  OFF
   tree-eh                                             :  ON
   tree-cfg                                            :  ON
   *warn_function_return                               :  ON
   *build_cgraph_edges                                 :  ON
   *free_lang_data                                     :  ON
   ipa-visibility                                      :  ON
   ipa-early_local_cleanups                            :  ON
      *free_cfg_annotations                            :  ON
      *init_datastructures                             :  ON
      tree-ompexp                                      :  OFF
      *referenced_vars                                 :  ON
      tree-ssa                                         :  ON
      tree-veclower                                    :  ON
      *early_warn_uninitialized                        :  OFF
      *rebuild_cgraph_edges                            :  ON
      tree-inline_param1                               :  ON
      tree-einline                                     :  ON
      tree-early_optimizations                         :  ON
         *remove_cgraph_callee_edges                   :  ON
         tree-copyrename1                              :  ON
         tree-ccp1                                     :  ON
         tree-forwprop1                                :  ON
         tree-ealias                                   :  ON
         tree-esra                                     :  ON
         tree-fre1                                     :  ON
         tree-copyprop1                                :  ON
         tree-mergephi1                                :  ON
         tree-cddce1                                   :  ON
         tree-eipa_sra                                 :  ON
         tree-tailr1                                   :  ON
         tree-switchconv                               :  ON
         tree-ehcleanup1                               :  OFF
         tree-profile_estimate                         :  ON
         tree-local-pure-const1                        :  ON
         tree-fnsplit                                  :  ON
      tree-release_ssa                                 :  ON
      *rebuild_cgraph_edges                            :  ON
      tree-inline_param2                               :  ON
   ipa-profile                                         :  OFF
      tree-feedback_fnsplit                            :  OFF
   ipa-increase_alignment                              :  OFF
   ipa-matrix-reorg                                    :  OFF
   ipa-emutls                                          :  OFF
   ipa-whole-program                                   :  ON
   ipa-profile_estimate                                :  ON
   ipa-cp                                              :  ON
   ipa-cdtor                                           :  OFF
   ipa-inline                                          :  ON (FORCED_OFF)
   ipa-pure-const                                      :  ON
   ipa-static-var                                      :  ON
   ipa-pta                                             :  OFF
   ipa-lto_gimple_out                                  :  OFF
   ipa-lto_decls_out                                   :  OFF
   tree-ehdisp                                         :  OFF
   *all_optimizations                                  :  ON
      *remove_cgraph_callee_edges                      :  ON
      *strip_predict_hints                             :  ON
      tree-copyrename2                                 :  ON
      tree-cunrolli                                    :  ON
      tree-ccp2                                        :  ON
      tree-forwprop2                                   :  ON
      tree-cdce                                        :  ON
      tree-alias                                       :  ON
      tree-retslot                                     :  ON
      tree-phiprop                                     :  ON
      tree-fre2                                        :  ON
      tree-copyprop2                                   :  ON
      tree-mergephi2                                   :  ON
      tree-vrp1                                        :  ON
      tree-dce1                                        :  ON
      tree-cselim                                      :  ON
      tree-ifcombine                                   :  ON
      tree-phiopt1                                     :  ON
      tree-tailr2                                      :  ON
      tree-ch                                          :  ON
      tree-stdarg                                      :  OFF
      tree-cplxlower                                   :  ON
      tree-sra                                         :  ON
      tree-copyrename3                                 :  ON
      tree-dom1                                        :  ON
      tree-phicprop1                                   :  ON
      tree-dse1                                        :  ON
      tree-reassoc1                                    :  ON
      tree-dce2                                        :  ON
      tree-forwprop3                                   :  ON
      tree-phiopt2                                     :  ON
      tree-objsz                                       :  ON
      tree-ccp3                                        :  ON
      tree-copyprop3                                   :  ON
      tree-sincos                                      :  ON
      tree-bswap                                       :  ON
      tree-crited                                      :  ON
      tree-pre                                         :  ON
      tree-sink                                        :  ON
      tree-loop                                        :  ON
         tree-loopinit                                 :  ON
         tree-lim1                                     :  ON
         tree-copyprop4                                :  ON
         tree-dceloop1                                 :  ON
         tree-unswitch                                 :  OFF (FORCED_ON)
         tree-sccp                                     :  ON
         *record_bounds                                :  ON
         tree-ckdd                                     :  OFF
         tree-ldist                                    :  OFF
         tree-copyprop5                                :  ON
         tree-graphite0                                :  OFF
            tree-graphite                              :  OFF
            tree-lim2                                  :  ON
            tree-copyprop6                             :  ON
            tree-dceloop2                              :  ON
         tree-ivcanon                                  :  ON
         tree-ifcvt                                    :  OFF
         tree-vect                                     :  OFF
            tree-veclower2                             :  OFF
            tree-dceloop3                              :  ON
         tree-pcom                                     :  OFF
         tree-cunroll                                  :  ON
         tree-slp                                      :  OFF
         tree-parloops                                 :  OFF
         tree-aprefetch                                :  OFF
         tree-ivopts                                   :  ON
         tree-loopdone                                 :  ON
      tree-recip                                       :  OFF
      tree-reassoc2                                    :  ON
      tree-vrp2                                        :  ON
      tree-dom2                                        :  ON
      tree-phicprop2                                   :  ON
      tree-cddce2                                      :  ON
      tree-tracer                                      :  OFF
      tree-uninit                                      :  OFF
      tree-dse2                                        :  ON
      tree-forwprop4                                   :  ON
      tree-phiopt3                                     :  ON
      tree-fab                                         :  ON
      tree-widening_mul                                :  ON
      tree-tailc                                       :  ON
      tree-copyrename4                                 :  ON
      tree-uncprop                                     :  ON
      tree-local-pure-const2                           :  ON
   tree-cplxlower0                                     :  ON
   tree-ehcleanup2                                     :  OFF
   tree-resx                                           :  OFF
   tree-nrv                                            :  ON
   tree-mudflap2                                       :  OFF
   tree-optimized                                      :  ON
   *warn_function_noreturn                             :  OFF
   rtl-expand                                          :  ON
   *rest_of_compilation                                :  ON
      *init_function                                   :  ON
      rtl-sibling                                      :  ON
      rtl-rtl_eh                                       :  OFF
      rtl-initvals                                     :  ON
      rtl-unshare                                      :  ON
      rtl-vregs                                        :  ON
      rtl-into_cfglayout                               :  ON
      rtl-jump                                         :  ON
      rtl-subreg1                                      :  ON
      rtl-dfinit                                       :  ON
      rtl-cse1                                         :  ON
      rtl-fwprop1                                      :  ON
      rtl-cprop1                                       :  ON
      rtl-rtl pre                                      :  ON
      rtl-hoist                                        :  OFF
      rtl-cprop2                                       :  ON
      rtl-store_motion                                 :  OFF
      rtl-cse_local                                    :  OFF
      rtl-ce1                                          :  ON
      rtl-reginfo                                      :  ON
      rtl-loop2                                        :  ON
         rtl-loop2_init                                :  ON
         rtl-loop2_invariant                           :  ON
         rtl-loop2_unswitch                            :  OFF
         rtl-loop2_unroll                              :  OFF
         rtl-loop2_doloop                              :  OFF
         rtl-loop2_done                                :  ON
      rtl-web                                          :  OFF
      rtl-cprop3                                       :  ON
      rtl-cse2                                         :  ON
      rtl-dse1                                         :  ON
      rtl-fwprop2                                      :  ON
      rtl-auto_inc_dec                                 :  OFF
      rtl-init-regs                                    :  ON
      rtl-ud_dce                                       :  ON
      rtl-combine                                      :  ON
      rtl-ce2                                          :  ON
      rtl-bbpart                                       :  OFF
      rtl-regmove                                      :  ON
      rtl-outof_cfglayout                              :  ON
      rtl-split1                                       :  ON
      rtl-subreg2                                      :  ON
      rtl-no-opt dfinit                                :  OFF
      *stack_ptr_mod                                   :  ON
      rtl-mode_sw                                      :  ON
      rtl-asmcons                                      :  ON
      rtl-sms                                          :  OFF
      rtl-sched1                                       :  OFF
      rtl-ira                                          :  ON
      *all-postreload                                  :  OFF
         rtl-postreload                                :  OFF
         rtl-gcse2                                     :  OFF
         rtl-split2                                    :  ON
         rtl-zee                                       :  ON
         rtl-cmpelim                                   :  OFF
         rtl-btl1                                      :  OFF
         rtl-pro_and_epilogue                          :  ON
         rtl-dse2                                      :  ON
         rtl-csa                                       :  ON
         rtl-peephole2                                 :  ON
         rtl-ce3                                       :  ON
         rtl-rnreg                                     :  OFF
         rtl-cprop_hardreg                             :  ON
         rtl-rtl_dce                                   :  ON
         rtl-bbro                                      :  ON
         rtl-btl2                                      :  OFF
         *leaf_regs                                    :  ON
         rtl-split4                                    :  ON
         rtl-sched2                                    :  ON
         *stack_regs                                   :  ON
            rtl-split3                                 :  OFF
            rtl-stack                                  :  ON
         rtl-alignments                                :  ON
         rtl-compgotos                                 :  ON
         rtl-vartrack                                  :  OFF
         *free_cfg                                     :  ON
         rtl-mach                                      :  ON
         rtl-barriers                                  :  ON
         rtl-dbr                                       :  OFF
         rtl-split5                                    :  OFF
         rtl-eh_ranges                                 :  OFF
         rtl-shorten                                   :  ON
         rtl-nothrow                                   :  ON
         rtl-final                                     :  ON
      rtl-dfinish                                      :  ON
   *clean_state                                        :  ON

  reply	other threads:[~2011-06-02  7:13 UTC|newest]

Thread overview: 30+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <BANLkTikXRUTmZZokg4OtJA5fBrWUG+7yZux3=CLDBox1Q+Qhtw@mail.gmail.com>
2011-06-01  8:51 ` Richard Guenther
2011-06-01 16:17   ` Xinliang David Li
2011-06-01 17:24     ` Xinliang David Li
2011-06-05 17:25       ` Xinliang David Li
2011-06-06 11:22       ` Richard Guenther
2011-06-06 15:54         ` Xinliang David Li
2011-06-06 15:59           ` Richard Guenther
2011-06-06 19:21         ` Xinliang David Li
2011-06-07 10:11           ` Richard Guenther
2011-06-01 19:29     ` Richard Guenther
2011-06-01 19:46       ` Xinliang David Li
2011-06-02  7:13         ` Xinliang David Li [this message]
2011-06-05 17:25           ` Xinliang David Li
2011-06-06 11:38           ` Richard Guenther
2011-06-06 16:00             ` Xinliang David Li
2011-06-06 19:23               ` Xinliang David Li
2011-06-07 10:10               ` Richard Guenther
2011-06-07 16:24                 ` Xinliang David Li
2011-06-07 19:09                   ` Xinliang David Li
2011-06-07 20:39                     ` Xinliang David Li
2011-06-08  9:06                       ` Richard Guenther
2011-06-08  8:54                     ` Richard Guenther
2011-06-09 22:16                     ` H.J. Lu
2011-06-09 22:24                       ` Carrot Wei
2011-06-09 22:32                       ` Xinliang David Li
2011-06-09 22:51                       ` Xinliang David Li
2011-06-09 23:28                         ` Xinliang David Li
2011-06-10  9:10                           ` Richard Guenther
2011-06-10 16:37                             ` Xinliang David Li
2011-06-01 19:29     ` Xinliang David Li

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