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    Fix AArch64 encodings for by element instructions. · 48d86a7a
    Tamar Christina authored
    Some instructions in Armv8-a place a limitation on FP16 registers that can be
    used as the register from which to select an element from.
    
    e.g. fmla restricts Rm to 4 bits when using an FP16 register.  This restriction
    does not apply for all instructions, e.g. fcmla does not have this restriction
    as it gets an extra bit from the M field.
    
    Unfortunately, this restriction to S_H was added for all _Em operands before,
    meaning for a large number of instructions you couldn't use the full register
    file.
    
    This fixes the issue by introducing a new operand _Em16 which applies this
    restriction only when paired with S_H and leaves the _Em and the other
    qualifiers for _Em16 unbounded (i.e. using the full 5 bit range).
    
    Also the patch updates all instructions that should be affected by this.
    
    opcodes/
    
    	PR binutils/23192
    	* aarch64-asm-2.c: Regenerate.
    	* aarch64-dis-2.c: Likewise.
    	* aarch64-opc-2.c: Likewise.
    	* aarch64-dis.c (aarch64_ext_reglane): Add AARCH64_OPND_Em16 constraint.
    	* aarch64-opc.c (operand_general_constraint_met_p,
    	aarch64_print_operand): Likewise.
    	* aarch64-tbl.h (aarch64_opcode_table): Change Em to Em16 for smlal,
    	smlal2, fmla, fmls, fmul, fmulx, sqrdmlah, sqrdlsh, fmlal, fmlsl,
    	fmlal2, fmlsl2.
    	(AARCH64_OPERANDS): Add Em2.
    
    gas/
    
    	PR binutils/23192
    	* config/tc-aarch64.c (process_omitted_operand, parse_operands): Add
    	AARCH64_OPND_Em16
    	* testsuite/gas/aarch64/advsimd-armv8_3.s: Expand tests to cover upper
    	16 registers.
    	* testsuite/gas/aarch64/advsimd-armv8_3.d: Likewise.
    	* testsuite/gas/aarch64/advsimd-compnum.s: Likewise.
    	* testsuite/gas/aarch64/advsimd-compnum.d: Likewise.
    	* testsuite/gas/aarch64/sve.d: Likewise.
    
    include/
    
    	PR binutils/23192
    	*opcode/aarch64.h (aarch64_opnd): Add AARCH64_OPND_Em16.
    
    (cherry picked from commit 369c9167
    
    )
    Signed-off-by: default avatarTamar Christina <tamar.christina@arm.com>
    48d86a7a