re PR middle-end/29274 (not using mulsidi3)

re PR middle-end/29274 (not using mulsidi3)

gcc/
	PR middle-end/29274
	* optabs.h (expand_widening_mult): Declare.
	* tree-pass.h (pass_optimize_widening_mul): Declare.
	* tree-ssa-math-opts.c (execute_optimize_widening_mul,
	gate_optimize_widening_mul): New static functions.
	(pass_optimize_widening_mul): New.
	* expr.c (expand_expr_real_2) <case WIDEN_MULT_EXPR>: New
	case.
	<case MULT_EXPR>: Remove support for widening multiplies.
	* tree.def (WIDEN_MULT_EXPR): Tweak comment.
	* cfgexpand.c (expand_debug_expr) <case WIDEN_MULT_EXPR>: Use
	simplify_gen_unary rather than directly building extensions.
	* tree-cfg.c (verify_gimple_assign_binary): Add tests for
	WIDEN_MULT_EXPR.
	* expmed.c (expand_widening_mult): New function.
	* passes.c (init_optimization_passes): Add pass_optimize_widening_mul.

gcc/testsuite/
	PR middle-end/29274
	* gcc.target/i386/wmul-1.c: New test.
	* gcc.target/i386/wmul-2.c: New test.
	* gcc.target/bfin/wmul-1.c: New test.
	* gcc.target/bfin/wmul-2.c: New test.

From-SVN: r158633