Hi All, 


This patch adds support for creating floating point constants
using mov immediate instructions.  The movi SIMD instruction can
be used for HFmode and SFmode constants, eg. for -0.0f we generate:

        movi     v0.2s, 0x80, lsl 24

More complex constants can be generated using an integer MOV or
MOV+MOVK:

     mov   w0, 48128
     movk  w0, 0x47f0, lsl 16
     fmov  s0, w0

We allow up to 3 instructions as this allows all HF, SF and most DF
constants to be generated without a literal load, and is overall best
for codesize.


Regression tested on aarch64-none-linux-gnu and no regressions.

OK for trunk?

Thanks,
Tamar


gcc/
2017-06-07  Tamar Christina  <tamar.christina@arm.com>

	* config/aarch64/aarch64.md (mov<mode>): Generalize.
	(*movhf_aarch64, *movsf_aarch64, *movdf_aarch64):
	Add integer and movi cases.