On Wed, 18 Aug 2021 at 22:42, Richard Henderson
<[email protected]> wrote:
>
> Use the environment variable to test an older ISA from
> the one supported by the host.
>
> Signed-off-by: Richard Henderson <[email protected]>
I think we should document this environment variable somewhere...
> + /*
> + * For debugging/testing purposes, allow the ISA to be reduced
> + * (but not extended) from the set detected above.
> + */
> +#ifdef CONFIG_DEBUG_TCG
> + {
> + char *opt = g_strdup(getenv("QEMU_TCG_DEBUG"));
Consider g_autofree ?
> + if (opt) {
> + for (char *o = strtok(opt, ","); o ; o = strtok(NULL, ",")) {
> + if (o[0] == 'v' &&
> + o[1] >= '4' &&
> + o[1] <= '0' + arm_arch &&
> + o[2] == 0) {
> + arm_arch = o[1] - '0';
> + continue;
> + }
> + if (strcmp(o, "!neon") == 0) {
> + use_neon_instructions = false;
> + continue;
> + }
> + if (strcmp(o, "help") == 0) {
> + printf("QEMU_TCG_DEBUG=<opt>{,<opt>} where <opt> is\n"
> + " v<N> select ARMv<N>\n"
> + " !neon disable ARM NEON\n");
> + exit(0);
> + }
We should complain about something in the variable we don't understand,
rather than just ignoring it.
> + }
> + g_free(opt);
> + }
> + }
> +#endif
> +
-- PMM
