[Arith] Support eq in detect_clip_bound

[wrongtest-intellif]

Hi~ this is a patch to handle EqNode in detect_clip_bound. We got some regression failure when using this methodology as the power of upstream arithmetic simplifier grows.

Many trivial cases like x >= 4, x in [0, 4] seems to get well simplified to x==4 and certain assumptions on some condition be non-eq comparation do not hold then.

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• cc @junrushao _{See #10317 for details}

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[wrongtest-intellif]

Could you kindly take a look at this? @Lunderberg

[Lunderberg]

I like it overall, especially as you pointed out that simplification preferentially changes inequalities into equalities where possible. I have a couple of suggestions, mostly to prevent letting conditions overwrite each other, but overall looks good!

[Lunderberg]

Should this also be conditioned on p.min_value.defined()? Otherwise, if p.max_value has already been set by another condition, this would overwrite that earlier bound. This would be a repetition of the condition inside the if(is_const_int(ret.coeff, -1)).

[Lunderberg]

Now that I think of it, maybe it would be better to collect an Optional<PrimExpr> min_value and Optional<PrimExpr> max_value. For inequalities, only one of the two is non-empty. For equality expressions, both are non-empty. That way, the logic of how to adjust p.min_value and p.max_value wouldn't need to be duplicated. I'm thinking something like the following:

Optional<PrimExpr> min_value = NullOpt;
Optional<PrimExpr> max_value = NullOpt;

if(is_const_int(ret.coeff, 1)) {
  min_value = -ret.base;
  if(is_eq) {
    max_value = min_value;
  }
} else if(is_const_int(ret.coeff, -1)) {
  max_value = ret.base;
  if(is_eq) {
    min_value = max_value;
  }
}

[Lunderberg]

For consistency, should this have the same check for if(!op->a.dtype().is_int()) as the other cases?

[Lunderberg]

Thank you for the changes, and LGTM!

Also, the current CI failure has appeared on a few other PRs as well, and should be fixable by rebasing onto main.