Re: [PATCH] Introduce TARGET_SUPPORTS_ALIASES

[Yuri Gribov]

On Mon, Jul 31, 2017 at 9:04 AM, Martin Liška  wrote:
> Hi.
>
> Doing the transformation suggested by Honza.
>
> Patch can bootstrap on ppc64le-redhat-linux and x86_64-linux-gnu and survives 
> regression tests.
> And I also verified that works on hppa2.0w-hp-hpux11.11 (target w/o aliasing 
> support).
>
> Ready to be installed?

A nit - you can probly get rid of ATTRIBUTE_UNUSED in note_mangling_alias now.

-Y

[PATCH] Introduce TARGET_SUPPORTS_ALIASES

[Martin Liška]

Hi.

Doing the transformation suggested by Honza.

Patch can bootstrap on ppc64le-redhat-linux and x86_64-linux-gnu and survives 
regression tests.
And I also verified that works on hppa2.0w-hp-hpux11.11 (target w/o aliasing 
support).

Ready to be installed?
Martin
>From f8584bcb678dba92241c20b3e81895a52fc865f3 Mon Sep 17 00:00:00 2001
From: marxin <mli...@suse.cz>
Date: Tue, 25 Jul 2017 13:11:28 +0200
Subject: [PATCH] Introduce TARGET_SUPPORTS_ALIASES

gcc/c-family/ChangeLog:

2017-07-25  Martin Liska  <mli...@suse.cz>

	* c-opts.c (c_common_post_options): Replace ASM_OUTPUT_DEF with
	TARGET_SUPPORTS_ALIASES.

gcc/ChangeLog:

2017-07-25  Martin Liska  <mli...@suse.cz>

	* asan.c (asan_protect_global): Replace ASM_OUTPUT_DEF with
	TARGET_SUPPORTS_ALIASES.
	* cgraph.c (cgraph_node::create_same_body_alias): Likewise.
	* ipa-visibility.c (can_replace_by_local_alias): Likewise.
	(optimize_weakref): Likewise.
	* symtab.c (symtab_node::noninterposable_alias): Likewise.
	* varpool.c (varpool_node::create_extra_name_alias): Likewise.
	* defaults.h: Introduce TARGET_SUPPORTS_ALIASES.

gcc/cp/ChangeLog:

2017-07-25  Martin Liska  <mli...@suse.cz>

	* decl2.c (get_tls_init_fn): Replace ASM_OUTPUT_DEF with
	TARGET_SUPPORTS_ALIASES.
	(handle_tls_init): Likewise.
	(note_mangling_alias): Likewise.
	* optimize.c (can_alias_cdtor): Likewise.
---
 gcc/asan.c|  4 +---
 gcc/c-family/c-opts.c | 22 --
 gcc/cgraph.c  |  7 ---
 gcc/cp/decl2.c| 23 ++-
 gcc/cp/optimize.c |  6 +++---
 gcc/defaults.h|  9 +
 gcc/ipa-visibility.c  | 15 +--
 gcc/symtab.c  |  6 +++---
 gcc/varpool.c |  6 +++---
 9 files changed, 50 insertions(+), 48 deletions(-)

diff --git a/gcc/asan.c b/gcc/asan.c
index 5f9275f6425..d8cb2b52c8b 100644
--- a/gcc/asan.c
+++ b/gcc/asan.c
@@ -1663,10 +1663,8 @@ asan_protect_global (tree decl)
   if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
 return false;
 
-#ifndef ASM_OUTPUT_DEF
-  if (asan_needs_local_alias (decl))
+  if (!TARGET_SUPPORTS_ALIASES && asan_needs_local_alias (decl))
 return false;
-#endif
 
   return true;
 }
diff --git a/gcc/c-family/c-opts.c b/gcc/c-family/c-opts.c
index 1657e7a4390..0b13a188c1b 100644
--- a/gcc/c-family/c-opts.c
+++ b/gcc/c-family/c-opts.c
@@ -957,16 +957,18 @@ c_common_post_options (const char **pfilename)
 
   if (flag_extern_tls_init)
 {
-#if !defined (ASM_OUTPUT_DEF) || !SUPPORTS_WEAK
-  /* Lazy TLS initialization for a variable in another TU requires
-	 alias and weak reference support. */
-  if (flag_extern_tls_init > 0)
-	sorry ("external TLS initialization functions not supported "
-	   "on this target");
-  flag_extern_tls_init = 0;
-#else
-  flag_extern_tls_init = 1;
-#endif
+  if (!TARGET_SUPPORTS_ALIASES || !SUPPORTS_WEAK)
+	{
+	  /* Lazy TLS initialization for a variable in another TU requires
+	 alias and weak reference support.  */
+	  if (flag_extern_tls_init > 0)
+	sorry ("external TLS initialization functions not supported "
+		   "on this target");
+
+	  flag_extern_tls_init = 0;
+	}
+  else
+	flag_extern_tls_init = 1;
 }
 
   if (num_in_fnames > 1)
diff --git a/gcc/cgraph.c b/gcc/cgraph.c
index 2f820f1bb67..356bcd311e1 100644
--- a/gcc/cgraph.c
+++ b/gcc/cgraph.c
@@ -582,10 +582,11 @@ cgraph_node *
 cgraph_node::create_same_body_alias (tree alias, tree decl)
 {
   cgraph_node *n;
-#ifndef ASM_OUTPUT_DEF
+
   /* If aliases aren't supported by the assembler, fail.  */
-  return NULL;
-#endif
+  if (!TARGET_SUPPORTS_ALIASES)
+return NULL;
+
   /* Langhooks can create same body aliases of symbols not defined.
  Those are useless. Drop them on the floor.  */
   if (symtab->global_info_ready)
diff --git a/gcc/cp/decl2.c b/gcc/cp/decl2.c
index 2a52f8ca3e2..5119d4e62cc 100644
--- a/gcc/cp/decl2.c
+++ b/gcc/cp/decl2.c
@@ -3156,11 +3156,9 @@ get_tls_init_fn (tree var)
   if (!flag_extern_tls_init && DECL_EXTERNAL (var))
 return NULL_TREE;
 
-#ifdef ASM_OUTPUT_DEF
   /* If the variable is internal, or if we can't generate aliases,
  call the local init function directly.  */
-  if (!TREE_PUBLIC (var))
-#endif
+  if (!TREE_PUBLIC (var) || !TARGET_SUPPORTS_ALIASES)
 return get_local_tls_init_fn ();
 
   tree sname = mangle_tls_init_fn (var);
@@ -4241,9 +4239,8 @@ handle_tls_init (void)
   tree init = TREE_PURPOSE (vars);
   one_static_initialization_or_destruction (var, init, true);
 
-#ifdef ASM_OUTPUT_DEF
   /* Output init aliases even with -fno-extern-tls-init.  */
-  if (TREE_PUBLIC (var))
+  if (TARGET_SUPPORTS_ALIASES && TREE_PUBLIC (var))
 	{
   tree single_init_fn = get_tls_init_fn (var);
 	  if (single_init_fn == NULL_TREE)
@@ -4253,7 +4250,6 @@ handle_tls_init (void)
 		(single_init_fn, fn);
 	  gcc_assert (alias != NULL);
 	}
-