Re: [PATCH 12/24] bsd-user/arm/target_arch_sigtramp.h: Signal Trampoline for arm

[Richard Henderson]

On 10/19/21 9:44 AM, Warner Losh wrote:
> +    /*
> +     * The code has to load r7 manually rather than using
> +     * "ldr r7, =SYS_return to make sure the size of the
> +     * code is correct.
> +     */

This comment was applicable to the original freebsd asm source; it has no bearing on the 
hex instructions below.

> +    uint32_t sigtramp_code[] = {
> +    /* 1 */ 0xE1A0000D,                  /* mov r0, sp */
> +    /* 2 */ 0xE2800000 + sigf_uc,        /* add r0, r0, #SIGF_UC */

I guess this was a bit of thumb1 source that accidentally became ABI?
Otherwise I can't think why you wouldn't squish the mov into the add.

Anyway,
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

r~