> Date: Mon, 19 Oct 2020 20:03:01 +0200
> From: Christian Weisgerber <na...@mips.inka.de>
>
> This decodes the UDF ("permanently undefined") instruction in ddb's
> arm64 disassembler. The particular immediate16 format appears to
> be unique to this instruction.
>
> OK? Or don't bother?
ok kettenis@
> Index: arch/arm64/arm64/disasm.c
> ===================================================================
> RCS file: /cvs/src/sys/arch/arm64/arm64/disasm.c,v
> retrieving revision 1.2
> diff -u -p -r1.2 disasm.c
> --- arch/arm64/arm64/disasm.c 11 Sep 2020 09:27:10 -0000 1.2
> +++ arch/arm64/arm64/disasm.c 19 Oct 2020 16:17:55 -0000
> @@ -3107,6 +3107,11 @@ OP4FUNC(op_tbz, b5, b40, imm14, Rt)
> PRINTF("\n");
> }
>
> +OP1FUNC(op_udf, imm16)
> +{
> + PRINTF("udf\t#0x%"PRIx64"\n", imm16);
> +}
> +
> OP4FUNC(op_udiv, sf, Rm, Rn, Rd)
> {
> PRINTF("udiv\t%s, %s, %s\n",
> @@ -3668,6 +3673,8 @@ struct insn_info {
> {{ 5,16}, { 0, 0}, { 0, 0}, { 0, 0}, { 0, 0}, { 0, 0}, { 0, 0}, { 0, 0}}
> #define FMT_IMM16_LL \
> {{ 5,16}, { 0, 2}, { 0, 0}, { 0, 0}, { 0, 0}, { 0, 0}, { 0, 0}, { 0, 0}}
> +#define FMT_IMM16_UDF \
> + {{ 0,16}, { 0, 0}, { 0, 0}, { 0, 0}, { 0, 0}, { 0, 0}, { 0, 0}, { 0, 0}}
> #define FMT_OP0_OP1_CRN_CRM_OP2_RT \
> {{19, 2}, {16, 3}, {12, 4}, { 8, 4}, { 5, 3}, { 0, 5}, { 0, 0}, { 0, 0}}
> #define FMT_IMM7_RT2_RN_RT \
> @@ -3786,6 +3793,7 @@ static const struct insn_info insn_table
> { 0xffffd800, 0xdac10000, FMT_Z_M_RN_RD, op_pacia },
> { 0xffffcc00, 0x4e284800, FMT_M_D_RN_RD, op_simd_aes },
> { 0xffff8c00, 0x5e280800, FMT_OP3_RN_RD, op_simd_sha_reg2 },
> + { 0xffff0000, 0x00000000, FMT_IMM16_UDF, op_udf },
> { 0xfff8f01f, 0xd500401f, FMT_OP1_CRM_OP2, op_msr_imm },
> { 0xfff80000, 0xd5080000, FMT_OP1_CRN_CRM_OP2_RT, op_sys },
> { 0xfff80000, 0xd5280000, FMT_OP1_CRN_CRM_OP2_RT, op_sysl },
> --
> Christian "naddy" Weisgerber na...@mips.inka.de
>
>
