alias.c (nonlocal_reference_p): Take a care for CALL_INSNS's fusage field.

	* alias.c (nonlocal_reference_p): Take a care for
	CALL_INSNS's fusage field.
	* calls.c (ECF_PURE): New flag.
	(emit_call_1): Handle ECF_PURE calls.
	(initialize_argument_information): Unset ECF_PURE flag too.
	(precompute_arguments): Precompute for ECF_PURE too.
	(expand_call): Handle ECF_PURE calls too.
	(emit_library_call_value_1): Rename no_queue argument to
	fn_type, accept value of 2 as pure function.
	(emit_library_call_value, emit_library_call): Rename no_queue argument
	to fn_type.
	* optabs.c (prepare_cmp_insn): Pass fn_type 2 to memcmp call.

	* tree.h (DECL_IS_PURE): New macro.
	(struct tree_decl): Add pure_flag.
	* c-common.c (enum attrs): Add attribute "pure".
	(init_attributes): Initialize attribute "pure"
	(decl_attributes): Handle attribute "pure".
	* extend.texi (Attribute "pure"): Document.
	* calls.c (expand_call): Add (mem:BLK (scratch)) to "equal from"
	in pure function.
	(flags_from_decl_or_type): Support attribute "pure".

From-SVN: r33138

1 files changed, 5 insertions, 0 deletions

diff --git a/gcc/tree.h b/gcc/tree.h
index 0332102..9c426fa 100644
--- a/gcc/tree.h
+++ b/gcc/tree.h
@@ -1253,6 +1253,10 @@ struct tree_type
    not an alias.  */
 #define DECL_IS_MALLOC(NODE) (FUNCTION_DECL_CHECK (NODE)->decl.malloc_flag)
 
+/* Nonzero in a FUNCTION_DECL means this function should be treated
+   as "pure" function (like const function, but may read global memory).  */
+#define DECL_IS_PURE(NODE) (FUNCTION_DECL_CHECK (NODE)->decl.pure_flag)
+
 /* Nonzero in a FIELD_DECL means it is a bit field, and must be accessed
    specially.  */
 #define DECL_BIT_FIELD(NODE) (FIELD_DECL_CHECK (NODE)->decl.bit_field_flag)
@@ -1392,6 +1396,7 @@ struct tree_decl
   unsigned comdat_flag : 1;
   unsigned malloc_flag : 1;
   unsigned no_limit_stack : 1;
+  unsigned pure_flag : 1;
 #ifdef ONLY_INT_FIELDS
   unsigned int built_in_class : 2;
 #else