* alias.c (can_address_p): Compnonents are not addressable if

	the containing type has alias set 0.
	(get_alias_set): Rework to use STRIP_NOPS.
	Only call front-end routine on object, type, or object with
	NOPs stripped, not inner values.
	Use language hook to call front-end routine.
	* builtins.c (get_memory_rtx): Always call set_mem_attributes.
	(expand_builtin_apply): Call set_mem_align on MEMs we make.
	Don't pass alignment to emit_block_move.
	(expand_builtin_memcpy, expand_builtin_va_copy): Likewise.
	(expand_builtin_memset): Likewise, but for clear_storage.
	* c-common.c (lang_get_alias_set): Renamed to c_common_alias_set
	and remove C++ specific parts.
	* c-common.h (c_common_get_alias_set): Add declaration.
	* c-lang.c (LANG_HOOKS_GET_ALIAS_SET): New macro.
	* calls.c (emit_call_1): Fix typo in sibcall_pop case.
	(save_fixed_argument_area): Call set_mem_align.
	Remove alignment in call to emit_block_move.
	(emit_library_call_value_1, store_one_arg): Likewise.
	(target_for_arg): Remove; disabled long ago.
	* emit-rtl.c (set_mem_attributes): Rework to only call get_mem_attrs
	once and similar cleanups.
	(offset_address): Use proper introductory comment.
	* expr.c (emit_block_move): Use alignment from that of MEM args, not
	from explicit operand; all callers changed.
	(clear_storage): Likewise.
	(expand_assignment): Don't call set_mem_alias_set on to_rtx.
	(store_field): Remove kludge on alias set used for to_rtx.
	(highest_pow2_factor, case *_DIV_EXPR): Never return 0.
	(expand_expr_unaligned): Call set_mem_attributes instead of
	set_mem_alias_set.
	* expr.h (emit_block_move, clear_storage): Remove ALIGN argument.
	* function.c (assign_stack_temp_for_type): Set MEM alignment.
	(expand_function_end): Track MEM attributes of trampolines.
	* ifcvt.c (noce_try_cmove_arith): Set alignment of new MEM.
	* integrate.c (copy_rtx_and_substitute, case CALL): Copy memory
	attributes from original.
	* langhooks.c (lang_hook_default_get_alias_set): New function.
	(hook_get_alias_set_0): New function.
	* langhooks.h (hook_get_alias_set_0): New declaration.
	(lang_hook_default_get_alias_set): Likewise.
	(LANG_HOOKS_GET_ALIAS_SET): New macro; add to initializer.
	* reload1.c (alter_reg): Use adjust_address_nv.
	* rtl.c (get_mode_alignment): Moved to here.
	* rtl.h (MEM_ALIGN): Take default from mode, if not BLKmode, and
	change default if unknown from 1 to BITS_PER_UNIT.
	* stor-layout.c (get_mode_alignment): Remove from here.
	* toplev.h (struct lang_hoks): Add get_alias_set field.
	* tree.h (lang_get_alias_set): Delete declaration.
	* config/arc/arc.c (arc_setup_incoming_varags): Set MEM alignment.
	* config/i386/i386.c (ix86_setup_incoming_varargs): Likewise.
	(ix86_va_arg): Likewise.
	* config/i960/i960.c (i960_setup_incoming_varargs): Likewise.
	* config/pa/pa.c (hppa_builtin_saveregs): Likewise.
	* config/sparc/sparc.c (sparc_va_arg): Likewise.
	* config/rs6000/rs6000.c (setup_incoming_varargs): Likewise.
	(expand_block_move_mem): Remove dead code.
	* cp/cp-lang.c (cxx_get_alias_set): New function.
	Point LANG_HOOKS_GET_ALIAS_SET to it.
	* f/com.c (LANG_HOOKS_GET_ALIAS_SET): New macro.
	(lang_get_alias_set): Delete.
	* java/lang.c (lang_get_alias_set): Deleted.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@46440 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 21 insertions, 23 deletions

diff --git a/gcc/alias.c b/gcc/alias.c
index af0141f8cb3..3de48b2973b 100644
--- a/gcc/alias.c
+++ b/gcc/alias.c
@@ -438,13 +438,18 @@ can_address_p (t)
   else if (TREE_CODE (t) == BIT_FIELD_REF)
     return 0;
 
+  /* Fields are addressable unless they are marked as nonaddressable or
+     the containing type has alias set 0.  */
   else if (TREE_CODE (t) == COMPONENT_REF
 	   && ! DECL_NONADDRESSABLE_P (TREE_OPERAND (t, 1))
+	   && get_alias_set (TREE_TYPE (TREE_OPERAND (t, 0))) != 0
 	   && can_address_p (TREE_OPERAND (t, 0)))
     return 1;
 
+  /* Likewise for arrays.  */
   else if ((TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF)
 	   && ! TYPE_NONALIASED_COMPONENT (TREE_TYPE (TREE_OPERAND (t, 0)))
+	   && get_alias_set (TREE_TYPE (TREE_OPERAND (t, 0))) != 0
 	   && can_address_p (TREE_OPERAND (t, 0)))
     return 1;
 
@@ -478,22 +483,25 @@ get_alias_set (t)
       tree inner = t;
       tree placeholder_ptr = 0;
 
+      /* Remove any nops, then give the language a chance to do
+	 something with this tree before we look at it.  */
+      STRIP_NOPS (t);
+      set = (*lang_hooks.get_alias_set) (t);
+      if (set != -1)
+	return set;
+
       /* First see if the actual object referenced is an INDIRECT_REF from a
-	 restrict-qualified pointer or a "void *".  Start by removing nops
-	 since we care only about the actual object.  Also replace
+	 restrict-qualified pointer or a "void *".  Replace
 	 PLACEHOLDER_EXPRs.  */
-      while (((TREE_CODE (inner) == NOP_EXPR
-	       || TREE_CODE (inner) == CONVERT_EXPR)
-	      && (TYPE_MODE (TREE_TYPE (inner))
-		  == TYPE_MODE (TREE_TYPE (TREE_OPERAND (inner, 0)))))
-	     || TREE_CODE (inner) == NON_LVALUE_EXPR
-	     || TREE_CODE (inner) == PLACEHOLDER_EXPR
+      while (TREE_CODE (inner) == PLACEHOLDER_EXPR
 	     || handled_component_p (inner))
 	{
 	  if (TREE_CODE (inner) == PLACEHOLDER_EXPR)
 	    inner = find_placeholder (inner, &placeholder_ptr);
 	  else
 	    inner = TREE_OPERAND (inner, 0);
+
+	  STRIP_NOPS (inner);
 	}
 
       /* Check for accesses through restrict-qualified pointers.  */
@@ -540,27 +548,16 @@ get_alias_set (t)
       /* Otherwise, pick up the outermost object that we could have a pointer
 	 to, processing conversion and PLACEHOLDER_EXPR as above.  */
       placeholder_ptr = 0;
-      while (((TREE_CODE (t) == NOP_EXPR || TREE_CODE (t) == CONVERT_EXPR)
- 	      && (TYPE_MODE (TREE_TYPE (t))
-		  == TYPE_MODE (TREE_TYPE (TREE_OPERAND (t, 0)))))
-	     || TREE_CODE (t) == NON_LVALUE_EXPR
-	     || TREE_CODE (t) == PLACEHOLDER_EXPR
+      while (TREE_CODE (t) == PLACEHOLDER_EXPR
 	     || (handled_component_p (t) && ! can_address_p (t)))
 	{
-	  /* Give the language a chance to do something with this tree
-	     before we go inside it.  */
-	  if ((set = lang_get_alias_set (t)) != -1)
-	    return set;
-
 	  if (TREE_CODE (t) == PLACEHOLDER_EXPR)
 	    t = find_placeholder (t, &placeholder_ptr);
 	  else
 	    t = TREE_OPERAND (t, 0);
-	}
 
-      /* Give the language another chance to do something.  */
-      if ((set = lang_get_alias_set (t)) != -1)
-	return set;
+	  STRIP_NOPS (t);
+	}
 
       /* If we've already determined the alias set for a decl, just return
 	 it.  This is necessary for C++ anonymous unions, whose component
@@ -580,7 +577,8 @@ get_alias_set (t)
     return TYPE_ALIAS_SET (t);
 
   /* See if the language has special handling for this type.  */
-  if ((set = lang_get_alias_set (t)) != -1)
+  set = (*lang_hooks.get_alias_set) (t);
+  if (set != -1)
     return set;
 
   /* There are no objects of FUNCTION_TYPE, so there's no point in