[Mid-end] Add TARGET_GIMPLE_FOLD_BUILTIN target hook.

gcc/

	* coretypes.h (gimple_stmt_iterator_d): Forward declare.
	(gimple_stmt_iterator): New typedef.
	* gimple.h (gimple_stmt_iterator): Rename to...
	(gimple_stmt_iterator_d): ... This.
	* doc/tm.texi.in (TARGET_FOLD_BUILTIN): Detail restriction that
	trees be valid for GIMPLE and GENERIC.
	(TARGET_GIMPLE_FOLD_BUILTIN): New.
	* gimple-fold.c (gimple_fold_call): Call target hook
	gimple_fold_builtin.
	* hooks.c (hook_bool_gsiptr_false): New.
	* hooks.h (hook_bool_gsiptr_false): New.
	* target.def (fold_stmt): New.
	* doc/tm.texi: Regenerate.

From-SVN: r198142

gcc/ChangeLog

@@ -1,3 +1,19 @@
+2013-04-22  James Greenhalgh  <james.greenhalgh@arm.com>
+
+	* coretypes.h (gimple_stmt_iterator_d): Forward declare.
+	(gimple_stmt_iterator): New typedef.
+	* gimple.h (gimple_stmt_iterator): Rename to...
+	(gimple_stmt_iterator_d): ... This.
+	* doc/tm.texi.in (TARGET_FOLD_BUILTIN): Detail restriction that
+	trees be valid for GIMPLE and GENERIC.
+	(TARGET_GIMPLE_FOLD_BUILTIN): New.
+	* gimple-fold.c (gimple_fold_call): Call target hook
+	gimple_fold_builtin.
+	* hooks.c (hook_bool_gsiptr_false): New.
+	* hooks.h (hook_bool_gsiptr_false): New.
+	* target.def (fold_stmt): New.
+	* doc/tm.texi: Regenerate.
+
 2013-04-22  Vladimir Makarov  <vmakarov@redhat.com>
 
 	PR target/57018

gcc/coretypes.h

@@ -62,6 +62,8 @@ union gimple_statement_d;
 typedef union gimple_statement_d *gimple;
 typedef const union gimple_statement_d *const_gimple;
 typedef gimple gimple_seq;
+struct gimple_stmt_iterator_d;
+typedef gimple_stmt_iterator_d gimple_stmt_iterator;
 union section;
 typedef union section section;
 struct gcc_options;

gcc/doc/tm.texi

@@ -10931,8 +10931,16 @@ Fold a call to a machine specific built-in function that was set up by
 @samp{TARGET_INIT_BUILTINS}.  @var{fndecl} is the declaration of the
 built-in function.  @var{n_args} is the number of arguments passed to
 the function; the arguments themselves are pointed to by @var{argp}.
-The result is another tree containing a simplified expression for the
+The result is another tree, valid for both GIMPLE and GENERIC,
-call's result.  If @var{ignore} is true the value will be ignored.
+containing a simplified expression for the call's result.  If
+@var{ignore} is true the value will be ignored.
+@end deftypefn
+
+@deftypefn {Target Hook} bool TARGET_GIMPLE_FOLD_BUILTIN (gimple_stmt_iterator *@var{gsi})
+Fold a call to a machine specific built-in function that was set up
+by @samp{TARGET_INIT_BUILTINS}.  @var{gsi} points to the gimple
+statement holding the function call.  Returns true if any change
+was made to the GIMPLE stream.
 @end deftypefn
 
 @deftypefn {Target Hook} int TARGET_COMPARE_VERSION_PRIORITY (tree @var{decl1}, tree @var{decl2})

gcc/doc/tm.texi.in

@@ -10775,10 +10775,13 @@ Fold a call to a machine specific built-in function that was set up by
 @samp{TARGET_INIT_BUILTINS}.  @var{fndecl} is the declaration of the
 built-in function.  @var{n_args} is the number of arguments passed to
 the function; the arguments themselves are pointed to by @var{argp}.
-The result is another tree containing a simplified expression for the
+The result is another tree, valid for both GIMPLE and GENERIC,
-call's result.  If @var{ignore} is true the value will be ignored.
+containing a simplified expression for the call's result.  If
+@var{ignore} is true the value will be ignored.
 @end deftypefn
 
+@hook TARGET_GIMPLE_FOLD_BUILTIN
+
 @hook TARGET_COMPARE_VERSION_PRIORITY
 This hook is used to compare the target attributes in two functions to
 determine which function's features get higher priority.  This is used

gcc/gimple-fold.c

@@ -1143,6 +1143,8 @@ gimple_fold_call (gimple_stmt_iterator *gsi, bool inplace)
 	    gimplify_and_update_call_from_tree (gsi, result);
 	  changed = true;
 	}
+      else if (DECL_BUILT_IN_CLASS (callee) == BUILT_IN_MD)
+	changed |= targetm.gimple_fold_builtin (gsi);
     }
 
   return changed;

gcc/gimple.h

@@ -139,7 +139,7 @@ enum plf_mask {
 
 /* Iterator object for GIMPLE statement sequences.  */
 
-typedef struct
+struct gimple_stmt_iterator_d
 {
   /* Sequence node holding the current statement.  */
   gimple_seq_node ptr;
@@ -150,8 +150,7 @@ typedef struct
      block/sequence is removed.  */
   gimple_seq *seq;
   basic_block bb;
-} gimple_stmt_iterator;
+};
-
 
 /* Data structure definitions for GIMPLE tuples.  NOTE: word markers
    are for 64 bit hosts.  */

gcc/hooks.c

@@ -147,6 +147,14 @@ hook_bool_FILEptr_rtx_false (FILE *a ATTRIBUTE_UNUSED,
   return false;
 }
 
+/* Generic hook that takes (gimple_stmt_iterator *) and returns
+   false.  */
+bool
+hook_bool_gsiptr_false (gimple_stmt_iterator *a ATTRIBUTE_UNUSED)
+{
+  return false;
+}
+
 /* Used for the TARGET_ASM_CAN_OUTPUT_MI_THUNK hook.  */
 bool
 hook_bool_const_tree_hwi_hwi_const_tree_false (const_tree a ATTRIBUTE_UNUSED,

gcc/hooks.h

@@ -42,6 +42,7 @@ extern bool hook_bool_tree_false (tree);
 extern bool hook_bool_const_tree_false (const_tree);
 extern bool hook_bool_tree_true (tree);
 extern bool hook_bool_const_tree_true (const_tree);
+extern bool hook_bool_gsiptr_false (gimple_stmt_iterator *);
 extern bool hook_bool_const_tree_hwi_hwi_const_tree_false (const_tree,
 							   HOST_WIDE_INT,
 							   HOST_WIDE_INT,

gcc/target.def

@@ -1289,13 +1289,24 @@ DEFHOOK
  "",
  tree, (unsigned int /*location_t*/ loc, tree fndecl, void *arglist), NULL)
 
-/* Fold a target-specific builtin.  */
+/* Fold a target-specific builtin to a tree valid for both GIMPLE
+   and GENERIC.  */
 DEFHOOK
 (fold_builtin,
  "",
  tree, (tree fndecl, int n_args, tree *argp, bool ignore),
  hook_tree_tree_int_treep_bool_null)
 
+/* Fold a target-specific builtin to a valid GIMPLE tree.  */
+DEFHOOK
+(gimple_fold_builtin,
+ "Fold a call to a machine specific built-in function that was set up\n\
+by @samp{TARGET_INIT_BUILTINS}.  @var{gsi} points to the gimple\n\
+statement holding the function call.  Returns true if any change\n\
+was made to the GIMPLE stream.",
+ bool, (gimple_stmt_iterator *gsi),
+ hook_bool_gsiptr_false)
+
 /* Target hook is used to compare the target attributes in two functions to
    determine which function's features get higher priority.  This is used
    during function multi-versioning to figure out the order in which two