CSE conversions within sincos

CSE conversions within sincos

On platforms in which Aux_[Real_Type] involves non-NOP conversions
(e.g., between single- and double-precision, or between short float
and float), the conversions before the calls are CSEd too late for
sincos to combine calls.

This patch enables the sincos pass to CSE type casts used as arguments
to eligible calls before looking for other calls using the same
operand.

for  gcc/ChangeLog

	* tree-ssa-math-opts.c (sincos_stats): Add conv_removed.
	(execute_cse_conv_1): New.
	(execute_cse_sincos_1): Call it.  Fix return within
	FOR_EACH_IMM_USE_STMT.
	(pass_cse_sincos::execute): Report conv_inserted.

for  gcc/testsuite/ChangeLog

	* gnat.dg/sin_cos.ads: New.
	* gnat.dg/sin_cos.adb: New.
	* gcc.dg/sin_cos.c: New.