[GAS, ARM, 2/16] Add CLI extension support for Armv8.1-M Mainline

This patch implements the dsp, fp and fp.dp extensions for Armv8.1-M Mainline.

This patch also removes the fp-armv8 check from the half-precision move
instructions 'do_neon_movhf', as checking that the FP16 instructions extension
feature bit is enabled 'ARM_EXT2_FP16_INST' is enough.

gas/ChangeLog:
2019-04-15  Andre Vieira  <andre.simoesdiasvieira@arm.com>

	* config/tc-arm.c (do_neon_movhf): Remove fp-armv8 check.
	(armv8_1m_main_ext_table): New extension table.
	(arm_archs): Use the new extension table.
	* doc/c-arm.texi: Add missing arch and document new extensions.
	* testsuite/gas/arm/armv8.1-m.main-fp.d: New.
	* testsuite/gas/arm/armv8.1-m.main-fp-dp.d: New.
	* testsuite/gas/arm/armv8.1-m.main-hp.d: New.

1 files changed, 11 insertions, 0 deletions

diff --git a/gas/doc/c-arm.texi b/gas/doc/c-arm.texi
index 184d716..4c595d8 100644
--- a/gas/doc/c-arm.texi
+++ b/gas/doc/c-arm.texi
@@ -250,6 +250,7 @@ names are recognized:
 @code{armv8.5-a},
 @code{armv8-m.base},
 @code{armv8-m.main},
+@code{armv8.1-m.main},
 @code{iwmmxt},
 @code{iwmmxt2}
 and
@@ -355,6 +356,16 @@ double-word registers.
 @code{+nofp}: Disables all FPU instructions.
 @code{+nodsp}: Disables DSP Extension.
 
+For @code{armv8.1-m.main}:
+
+@code{+dsp}: Enables DSP Extension.
+@code{+fp}: Enables single and half precision scalar Floating Point Extensions
+for Armv8.1-M Mainline with 16 double-word registers.
+@code{+fp.dp}: Enables double precision scalar Floating Point Extensions for
+Armv8.1-M Mainline, implies @code{+fp}.
+@code{+nofp}: Disables all FPU instructions.
+@code{+nodsp}: Disables DSP Extension.
+
 For @code{armv8-a}:
 
 @code{+crc}: Enables CRC32 Extension.