[PATCH 19/21] PR jit/63854: Fix leak of ipa hooks

[David Malcolm <dmalcolm at redhat dot com>]

This fixes three leaks in IPA seen in jit testcases with valgrind:

This one:
96 bytes in 4 blocks are definitely lost in loss record 102 of 205
   at 0x4A0645D: malloc (in /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so)
   by 0x5D76447: xmalloc (xmalloc.c:147)
   by 0x4E35C23: symbol_table::add_cgraph_insertion_hook(void (*)(cgraph_node*, void*), void*) (cgraph.c:383)
   by 0x51070C6: ipa_register_cgraph_hooks() (ipa-prop.c:3864)
   by 0x5C753D8: ipcp_generate_summary() (ipa-cp.c:3786)
   by 0x5223540: execute_ipa_summary_passes(ipa_opt_pass_d*) (passes.c:2102)
   by 0x4E49A60: ipa_passes() (cgraphunit.c:2074)
   by 0x4E49E2C: symbol_table::compile() (cgraphunit.c:2172)
   by 0x4E4A1C2: symbol_table::finalize_compilation_unit() (cgraphunit.c:2325)
   by 0x4DC999C: jit_langhook_write_globals() (dummy-frontend.c:216)
   by 0x532B3A6: compile_file() (toplev.c:583)
   by 0x532E15F: do_compile() (toplev.c:2020)

appears to be caused by
  ipa-prop.c (ipa_register_cgraph_hooks)
unconditionally inserting ipa_add_new_function as
"function_insertion_hook_holder", rather than if the latter is
non-NULL, like the other hooks.

These two in ipa-reference.c:
96 bytes in 4 blocks are definitely lost in loss record 103 of 205
   at 0x4A0645D: malloc (in /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so)
   by 0x5D76447: xmalloc (xmalloc.c:147)
   by 0x4E35AA9: symbol_table::add_cgraph_removal_hook(void (*)(cgraph_node*, void*), void*) (cgraph.c:329)
   by 0x5CA446E: ipa_init() (ipa-reference.c:435)
   by 0x5CA47D1: generate_summary() (ipa-reference.c:551)
   by 0x5CA4E70: propagate() (ipa-reference.c:684)
   by 0x5CA640E: (anonymous namespace)::pass_ipa_reference::execute(function*) (ipa-reference.c:1178)
   by 0x5223CC1: execute_one_pass(opt_pass*) (passes.c:2306)
   by 0x5224B9B: execute_ipa_pass_list(opt_pass*) (passes.c:2700)
   by 0x4E49B0D: ipa_passes() (cgraphunit.c:2088)
   by 0x4E49E2C: symbol_table::compile() (cgraphunit.c:2172)
   by 0x4E4A1C2: symbol_table::finalize_compilation_unit() (cgraphunit.c:2325)

96 bytes in 4 blocks are definitely lost in loss record 104 of 205
   at 0x4A0645D: malloc (in /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so)
   by 0x5D76447: xmalloc (xmalloc.c:147)
   by 0x4E35E29: symbol_table::add_cgraph_duplication_hook(void (*)(cgraph_node*, cgraph_node*, void*), void*) (cgraph.c:453)
   by 0x5CA4493: ipa_init() (ipa-reference.c:437)
   by 0x5CA47D1: generate_summary() (ipa-reference.c:551)
   by 0x5CA4E70: propagate() (ipa-reference.c:684)
   by 0x5CA640E: (anonymous namespace)::pass_ipa_reference::execute(function*) (ipa-reference.c:1178)
   by 0x5223CC1: execute_one_pass(opt_pass*) (passes.c:2306)
   by 0x5224B9B: execute_ipa_pass_list(opt_pass*) (passes.c:2700)
   by 0x4E49B0D: ipa_passes() (cgraphunit.c:2088)
   by 0x4E49E2C: symbol_table::compile() (cgraphunit.c:2172)
   by 0x4E4A1C2: symbol_table::finalize_compilation_unit() (cgraphunit.c:2325)

appear to be due to th hooks never being removed.

My patch hacks in a removal of them into ipa_reference_c_finalize, but
I suspect there's a cleaner place to put this.

gcc/ChangeLog:
	PR jit/63854
	* ipa-prop.c (ipa_register_cgraph_hooks): Guard insertion of
	ipa_add_new_function on function_insertion_hook_holder being
	non-NULL.
	* ipa-reference.c (ipa_reference_c_finalize): Remove
	node_removal_hook_holder and node_duplication_hook_holder if
	they've been added to symtab.
	* toplev.c (toplev::finalize): Call ipa_reference_c_finalize
	before cgraph_c_finalize so that the former can access "symtab".
---
 gcc/ipa-prop.c      |  3 ++-
 gcc/ipa-reference.c | 11 +++++++++++
 gcc/toplev.c        |  4 +++-
 3 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/gcc/ipa-prop.c b/gcc/ipa-prop.c
index f87243c..a8238ac 100644
--- a/gcc/ipa-prop.c
+++ b/gcc/ipa-prop.c
@@ -3552,7 +3552,8 @@ ipa_register_cgraph_hooks (void)
   if (!node_duplication_hook_holder)
     node_duplication_hook_holder =
       symtab->add_cgraph_duplication_hook (&ipa_node_duplication_hook, NULL);
-  function_insertion_hook_holder =
+  if (!function_insertion_hook_holder)
+    function_insertion_hook_holder =
       symtab->add_cgraph_insertion_hook (&ipa_add_new_function, NULL);
 }
 
diff --git a/gcc/ipa-reference.c b/gcc/ipa-reference.c
index 1ce06d1..b046f9e 100644
--- a/gcc/ipa-reference.c
+++ b/gcc/ipa-reference.c
@@ -1198,4 +1198,15 @@ ipa_reference_c_finalize (void)
       bitmap_obstack_release (&optimization_summary_obstack);
       ipa_init_p = false;
     }
+
+  if (node_removal_hook_holder)
+    {
+      symtab->remove_cgraph_removal_hook (node_removal_hook_holder);
+      node_removal_hook_holder = NULL;
+    }
+  if (node_duplication_hook_holder)
+    {
+      symtab->remove_cgraph_duplication_hook (node_duplication_hook_holder);
+      node_duplication_hook_holder = NULL;
+    }
 }
diff --git a/gcc/toplev.c b/gcc/toplev.c
index c0c418c..96e7af9 100644
--- a/gcc/toplev.c
+++ b/gcc/toplev.c
@@ -2162,12 +2162,14 @@ 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 ();
+
   cgraph_c_finalize ();
   cgraphunit_c_finalize ();
   dwarf2out_c_finalize ();
   gcse_c_finalize ();
   ipa_cp_c_finalize ();
-  ipa_reference_c_finalize ();
   ira_costs_c_finalize ();
   params_c_finalize ();
 
-- 
1.8.5.3