Re: [Qemu-devel] [PATCH] target/arm: Allow ARMv6-M Thumb2 instructions

[Peter Maydell]

On 12 June 2018 at 21:46, Julia Suvorova <address@hidden> wrote:
> ARMv6-M supports 6 Thumb2 instructions. This patch checks for these
> instructions and allows their execution.
> Like Thumb2 cores, ARMv6-M always interprets BL instruction as 32-bit.
>
> This patch is required for future Cortex-M0 support.
>
> Signed-off-by: Julia Suvorova <address@hidden>
> @@ -10075,6 +10076,11 @@ static void disas_thumb2_insn(DisasContext *s, 
> uint32_t insn)
>  {
>      uint32_t imm, shift, offset;
>      uint32_t rd, rn, rm, rs;
> +    uint32_t armv6m_insn[] = {0xf3808000 /* msr */, 0xf3b08040 /* dsb */,
> +                              0xf3b08050 /* dmb */, 0xf3b08060 /* isb */,
> +                              0xf3e08000 /* mrs */, 0xf000d000 /* bl */};
> +    uint32_t armv6m_mask[] = {0xffe0d000, 0xfff0d0f0, 0xfff0d0f0,
> +                              0xfff0d0f0, 0xffe0d000, 0xf800d000};

I think these arrays should be 'const'; we can also move them closer
to their point of use, inside the scope of the if() below.

Since those are trivial tweaks, I'm going to put this into
target-arm.next with those changes made, if that's OK.

thanks
-- PMM