[PATCH 04/16] gcc: Don't keep reinitializing RTL

[David Malcolm <dmalcolm@redhat.com>]

This may be something of a hack; it appears to work for x86_64.

Before:
initialize rtl          :   1.50 (63%) usr   0.02 (10%) sys   1.34 (23%) wall    1156 kB ( 5%) ggc
rest of compilation     :   0.01 ( 0%) usr   0.00 ( 0%) sys   0.03 ( 1%) wall     232 kB ( 1%) ggc
TOTAL                 :   2.37             0.21             5.86              21438 kB
./test-benchmark.c.exe: 100 iterations at optlevel 0 took a total of 5.870s (0.059s per iteration)

After:
initialize rtl          :   0.01 ( 1%) usr   0.01 ( 4%) sys   0.02 ( 0%) wall      12 kB ( 0%) ggc
rest of compilation     :   0.03 ( 3%) usr   0.01 ( 4%) sys   0.03 ( 1%) wall     232 kB ( 1%) ggc
TOTAL                 :   1.03             0.24             4.53              20294 kB
./test-benchmark.c.exe: 100 iterations at optlevel 0 took a total of 4.530s (0.045s per iteration)

(i.e. saves about 10-15ms per iteration)

gcc/ChangeLog:
	* ira-costs.c (ira_costs_c_finalize): Delete.
	* ira.h (void ira_costs_c_finalize): Delete.
	* toplev.c (lang_dependent_init_target): Remove assertion tha
	this_target_rtl->target_specific_initialized is false.
	(finalize): Remove call to lra_finish_once.
	(toplev::finalize): Don't unset "rtl_initialized" and
	"this_target_rtl->target_specific_initialized".  Remove call t
	ira_costs_c_finalize.
---
 gcc/ira-costs.c | 6 ------
 gcc/ira.h       | 3 ---
 gcc/toplev.c    | 8 --------
 3 files changed, 17 deletions(-)

diff --git a/gcc/ira-costs.c b/gcc/ira-costs.c
index fa6aec4..cfe416d 100644
--- a/gcc/ira-costs.c
+++ b/gcc/ira-costs.c
@@ -2367,9 +2367,3 @@ ira_adjust_equiv_reg_cost (unsigned regno, int cost)
   else
     regno_equiv_gains[regno] += cost;
 }
-
-void
-ira_costs_c_finalize (void)
-{
-  this_target_ira_int->free_ira_costs ();
-}
diff --git a/gcc/ira.h b/gcc/ira.h
index 5b52cb1..306692d 100644
--- a/gcc/ira.h
+++ b/gcc/ira.h
@@ -206,7 +206,4 @@ extern bool ira_bad_reload_regno (int, rtx, rtx);
 
 extern void ira_adjust_equiv_reg_cost (unsigned, int);
 
-/* ira-costs.c */
-extern void ira_costs_c_finalize (void);
-
 #endif /* GCC_IRA_H */
diff --git a/gcc/toplev.c b/gcc/toplev.c
index 3527b5d..12806d0 100644
--- a/gcc/toplev.c
+++ b/gcc/toplev.c
@@ -1806,8 +1806,6 @@ lang_dependent_init_target (void)
      front end is initialized.  It also depends on the HAVE_xxx macros
      generated from the target machine description.  */
   init_optabs ();
-
-  gcc_assert (!this_target_rtl->target_specific_initialized);
 }
 
 /* Perform initializations that are lang-dependent or target-dependent.
@@ -1998,8 +1996,6 @@ finalize (bool no_backend)
       statistics_fini ();
 
       g->get_passes ()->finish_optimization_passes ();
-
-      lra_finish_once ();
     }
 
   if (mem_report)
@@ -2207,9 +2203,6 @@ toplev::main (int argc, char **argv)
 void
 toplev::finalize (void)
 {
-  rtl_initialized = false;
-  this_target_rtl->target_specific_initialized = false;
-
   /* Needs to be called before cgraph_c_finalize since it uses symtab.  */
   ipa_reference_c_finalize ();
 
@@ -2218,7 +2211,6 @@ toplev::finalize (void)
   dwarf2out_c_finalize ();
   gcse_c_finalize ();
   ipa_cp_c_finalize ();
-  ira_costs_c_finalize ();
   params_c_finalize ();
 
   finalize_options_struct (&global_options);
-- 
1.8.5.3