Gimple match results are represented by a code_helper for the operation,
a tree for the type, and an array of three trees for the operands.
This patch wraps them up in a class so that they don't need to be
passed around individually.

The main reason for doing this is to make it easier to increase the
number of operands (for calls) or to support more complicated kinds
of operation.  But passing around fewer operands also helps to reduce
the size of gimple-match.o (about 7% for development builds and 4% for
release builds).

2018-05-24  Richard Sandiford  <richard.sandiford@linaro.org>

gcc/
	* gimple-match.h (gimple_match_op): New class.
	(mprts_hook): Replace parameters with a gimple_match_op *.
	(maybe_build_generic_op): Likewise.
	(gimple_simplified_result_is_gimple_val): Replace parameters with
	a const gimple_match_op *.
	(gimple_simplify): Replace code_helper * and tree * parameters with
	a gimple_match_op * parameter.
	(gimple_resimplify1): Replace code_helper *, tree and tree *
	parameters with a gimple_match_op * parameter.
	(gimple_resimplify2): Likewise.
	(gimple_resimplify3): Likewise.
	(maybe_push_res_to_seq): Replace code_helper, tree and tree *
	parameters with a gimple_match_op * parameter.
	* gimple-match-head.c (gimple_simplify): Change prototypes of
	auto-generated functions to take a gimple_match_op * instead of
	separate code_helper * and tree * parameters.  Make the same
	change in the top-level overload and update calls to the
	gimple_resimplify routines.  Update calls to the auto-generated
	functions and to maybe_push_res_to_seq in the publicly-facing
	operation-specific gimple_simplify overloads.
	(gimple_match_op::MAX_NUM_OPS): Define.
	(gimple_resimplify1): Replace rcode and ops with a single res_op
	parameter.  Update call to gimple_simplify.
	(gimple_resimplify2): Likewise.
	(gimple_resimplify3): Likewise.
	(mprts_hook): Replace parameters with a gimple_match_op *.
	(maybe_build_generic_op): Likewise.
	(build_call_internal): Replace type, nargs and ops with
	a gimple_match_op *.
	(maybe_push_res_to_seq): Replace res_code, type and ops parameters
	with a single gimple_match_op *.  Update calls to mprts_hook,
	build_call_internal and gimple_simplified_result_is_gimple_val.
	Factor out code that is common to the tree_code and combined_fn cases.
	* genmatch.c (expr::gen_transform): Replace tem_code and
	tem_ops with a gimple_match_op called tem_op.  Update calls
	to the gimple_resimplify functions and maybe_push_res_to_seq.
	(dt_simplify::gen_1): Manipulate res_op instead of res_code and
	res_ops.  Update call to the gimple_resimplify functions.
	(dt_simplify::gen): Pass res_op instead of res_code and res_ops.
	(decision_tree::gen): Make the functions take a gimple_match_op *
	called res_op instead of separate res_code and res_ops parameters.
	Update call accordingly.
	* gimple-fold.c (replace_stmt_with_simplification): Replace rcode
	and ops with a single res_op parameter.  Update calls to
	maybe_build_generic_op and maybe_push_res_to_seq.
	(fold_stmt_1): Update calls to gimple_simplify and
	replace_stmt_with_simplification.
	(gimple_fold_stmt_to_constant_1): Update calls to gimple_simplify
	and gimple_simplified_result_is_gimple_val.
	* tree-cfgcleanup.c (cleanup_control_expr_graph): Update call to
	gimple_simplify.
	* tree-ssa-sccvn.c (vn_lookup_simplify_result): Replace parameters
	with a gimple_match_op *.
	(vn_nary_build_or_lookup): Likewise.  Update call to
	vn_nary_build_or_lookup_1.
	(vn_nary_build_or_lookup_1): Replace rcode, type and ops with a
	gimple_match_op *.  Update calls to the gimple_resimplify routines
	and to gimple_simplified_result_is_gimple_val.
	(vn_nary_simplify): Update call to vn_nary_build_or_lookup_1.
	Use gimple_match_op::MAX_NUM_OPS instead of a hard-coded 3.
	(vn_reference_lookup_3): Update call to vn_nary_build_or_lookup.
	(visit_nary_op): Likewise.
	(visit_reference_op_load): Likewise.

From-SVN: r260634