Re: [PATCH bpf-next v2 1/2] bpf: Get better reg range with ldsx and 32bit compare

Yonghong Song <yonghong.song@xxxxxxxxx> · Fri, 12 Jul 2024 14:24:52 -0700

On 7/12/24 1:30 PM, Alexei Starovoitov wrote:
On Fri, Jul 12, 2024 at 1:28 PM Yonghong Song <yonghong.song@xxxxxxxxx> wrote:
+       if (reg->s32_min_value >= 0) {
+               if ((reg->smin_value >= S32_MIN && reg->smax_value <= S32_MAX) ||
+                   (reg->smin_value >= S16_MIN && reg->smax_value <= S16_MAX) ||
+                   (reg->smin_value >= S8_MIN && reg->smax_value <= S8_MAX)) {
Could you do:
if (reg->s32_min_value >= 0 &&
     (reg->smin_value >= S32_MIN ...

to remove one indent below.

Ack. Will make proper change in the next revision.

+                       reg->smin_value = reg->umin_value = reg->s32_min_value;
+                       reg->smax_value = reg->umax_value = reg->s32_max_value;
+                       reg->var_off = tnum_intersect(reg->var_off,
+                                                     tnum_range(reg->smin_value,
+                                                                reg->smax_value));