Re: [PATCH v2 7/8] transform (A << S) >> S into A & (-1 >> S)

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On Mon, Aug 7, 2017 at 12:12 PM, Luc Van Oostenryck
<luc.vanoostenryck@xxxxxxxxx> wrote:
> +               // replace (A << S) >> S
> +               // by      A & (-1 >> S)

Umm. This seems misleading.

Don't you mean "value of all ones of the same size as A, shifted right by S"

> +               insn->src2 = value_pseudo(-1ULL >> value);

..and this seems buggy. There's a lot of bits in -1ULL, but what if
the size of 'S' is only 32-bit?

So I think you should take the size of A into account?

Or am I missing something?

             Linus
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