re PR tree-optimization/81741 (Misoptimisation : replacing a constant field read access by a function call)

	PR tree-optimization/81741
	PR tree-optimization/71947
	* tree-ssa-dom.c: Include tree-inline.h.
	(record_temporary_equivalences): Only record SSA_NAME = SSA_NAME
	equivalences if one is more expensive to compute than the other.
	* tree-ssa-scopedtables.h (class const_or_copies): Make
	record_const_or_copy_raw method private.
	(class avail_exprs_stack): New method simplify_binary_operation.
	* tree-ssa-scopedtables.c (avail_exprs_stack::lookup_avail_expr): Call
	avail_exprs_stack::simplify_binary_operation as needed.
	(avail_exprs_stack::simplify_binary_operation): New function.

	PR tree-optimization/81741
	PR tree-optimization/71947
	* gcc.dg/tree-ssa/pr81741.c: New test.
	* gcc.dg/tree-ssa/pr71947-7.c: New test.
	* gcc.dg/tree-ssa/pr71947-8.c: New test.
	* gcc.dg/tree-ssa/pr71947-9.c: New test.
	* gcc.dg/tree-ssa/pr71941-1.c: Tweak expected output.
	* gcc.dg/tree-ssa/pr71941-2.c: Tweak expected output.
	* gcc.dg/tree-ssa/pr71941-3.c: Tweak expected output.
	* gcc.dg/tree-ssa/20030922-2.c: xfail.

From-SVN: r251279