Simplify {gimplify_and_,}update_call_from_tree API

Simplify {gimplify_and_,}update_call_from_tree API

This removes update_call_from_tree in favor of
gimplify_and_update_call_from_tree, removing some code duplication
and simplifying the API use.  Some users of update_call_from_tree
have been transitioned to replace_call_with_value and the API
and its dependences have been moved to gimple-fold.h.

This shaves off another user of valid_gimple_rhs_p which is now
only used from within gimple-fold.c and thus moved and made private.

2021-04-14  Richard Biener  <rguenther@suse.de>

	* tree-ssa-propagate.h (valid_gimple_rhs_p): Remove.
	(update_gimple_call): Likewise.
	(update_call_from_tree): Likewise.
	* tree-ssa-propagate.c (valid_gimple_rhs_p): Remove.
	(valid_gimple_call_p): Likewise.
	(move_ssa_defining_stmt_for_defs): Likewise.
	(finish_update_gimple_call): Likewise.
	(update_gimple_call): Likewise.
	(update_call_from_tree): Likewise.
	(propagate_tree_value_into_stmt): Use replace_call_with_value.
	* gimple-fold.h (update_gimple_call): Declare.
	* gimple-fold.c (valid_gimple_rhs_p): Move here from
	tree-ssa-propagate.c.
	(update_gimple_call): Likewise.
	(valid_gimple_call_p): Likewise.
	(finish_update_gimple_call): Likewise, and simplify.
	(gimplify_and_update_call_from_tree): Implement
	update_call_from_tree functionality, avoid excessive
	push/pop_gimplify_context.
	(gimple_fold_builtin): Use only gimplify_and_update_call_from_tree.
	(gimple_fold_call): Likewise.
	* gimple-ssa-sprintf.c (try_substitute_return_value): Likewise.
	* tree-ssa-ccp.c (ccp_folder::fold_stmt): Likewise.
	(pass_fold_builtins::execute): Likewise.
	(optimize_stack_restore): Use replace_call_with_value.
	* tree-cfg.c (fold_loop_internal_call): Likewise.
	* tree-ssa-dce.c (maybe_optimize_arith_overflow): Use
	only gimplify_and_update_call_from_tree.
	* tree-ssa-strlen.c (handle_builtin_strlen): Likewise.
	(handle_builtin_strchr): Likewise.
	* tsan.c: Include gimple-fold.h instead of tree-ssa-propagate.h.

	* config/rs6000/rs6000-call.c (rs6000_gimple_fold_builtin):
	Use replace_call_with_value.