This patch makes the scalar_mode_supported_p target hook take a
scalar_mode rather than a machine_mode.

2017-08-30  Richard Sandiford  <richard.sandiford@linaro.org>
	    Alan Hayward  <alan.hayward@arm.com>
	    David Sherwood  <david.sherwood@arm.com>

gcc/
	* target.def (scalar_mode_supported_p): Take a scalar_mode
	instead of a machine_mode.
	* targhooks.h (default_scalar_mode_supported_p): Likewise.
	* targhooks.c (default_scalar_mode_supported_p): Likewise.
	* config/aarch64/aarch64.c (aarch64_scalar_mode_supported_p): Likewise.
	* config/alpha/alpha.c (alpha_scalar_mode_supported_p): Likewise.
	* config/arm/arm.c (arm_scalar_mode_supported_p): Likewise.
	* config/avr/avr.c (avr_scalar_mode_supported_p): Likewise.
	* config/c6x/c6x.c (c6x_scalar_mode_supported_p): Likewise.
	* config/i386/i386.c (ix86_scalar_mode_supported_p): Likewise.
	* config/ia64/ia64.c (ia64_scalar_mode_supported_p): Likewise.
	* config/mips/mips.c (mips_scalar_mode_supported_p): Likewise.
	* config/msp430/msp430.c (msp430_scalar_mode_supported_p): Likewise.
	* config/pa/pa.c (pa_scalar_mode_supported_p): Likewise.
	* config/pdp11/pdp11.c (pdp11_scalar_mode_supported_p): Likewise.
	* config/powerpcspe/powerpcspe.c (rs6000_scalar_mode_supported_p):
	Likewise.
	* config/rs6000/rs6000.c (rs6000_scalar_mode_supported_p): Likewise.
	* config/s390/s390.c (s390_scalar_mode_supported_p): Likewise.
	* config/spu/spu.c (spu_scalar_mode_supported_p): Likewise.
	* config/tilegx/tilegx.c (tilegx_scalar_mode_supported_p): Likewise.
	* config/tilepro/tilepro.c (tilepro_scalar_mode_supported_p):
	Likewise.
	* doc/tm.texi: Regenerate.

gcc/c-family/
	* c-attribs.c (vector_mode_valid_p) Fold GET_MODE_INNER call
	into scalar_mode_supported_p call.
	(handle_mode_attribute): Update call to scalar_mode_supported_p.

Co-Authored-By: Alan Hayward <alan.hayward@arm.com>
Co-Authored-By: David Sherwood <david.sherwood@arm.com>

From-SVN: r251523