match.pd: Some build_nonstandard_integer_type tweaks
As discussed earlier, using build_nonstandard_integer_type blindly for all INTEGRAL_TYPE_Ps is problematic now that we have BITINT_TYPE, because it always creates an INTEGRAL_TYPE with some possibly very large precision. The following patch attempts to deal with 3 such spots in match.pd, others still need looking at. In the first case, I think it is quite expensive/undesirable to create a non-standard INTEGER_TYPE with possibly huge precision and then immediately just see type_has_mode_precision_p being false for it, or even worse introducing a cast to TImode or OImode or XImode INTEGER_TYPE which nothing will be able to actually handle. 128-bit or 64-bit (on 32-bit targets) types are the largest supported by the backend, so the following patch avoids creating and matching conversions to larger types, it is an optimization anyway and so should be used when it is cheap that way. In the second hunk, I believe the uses of build_nonstandard_integer_type aren't useful at all. It is when matching a ? -1 : 0 and trying to express it as say -(type) (bool) a etc., but this is all GIMPLE only, where most of integral types with same precision/signedness are compatible and we know -1 is representable in that type, so I really don't see any reason not to perform the negation of a [0, 1] valued expression in type, rather than doing it in build_nonstandard_integer_type (TYPE_PRECISION (type), TYPE_UNSIGNED (type)) (except that it breaks the BITINT_TYPEs). I don't think we need to do something like range_check_type. While in there, I've also noticed it was using a (with { tree booltrue = constant_boolean_node (true, boolean_type_node); } and removed that + replaced uses of booltrue with boolean_true_node which the above function always returns. 2023-09-19 Jakub Jelinek <jakub@redhat.com> * match.pd ((x << c) >> c): Don't call build_nonstandard_integer_type nor check type_has_mode_precision_p for width larger than [TD]Imode precision. (a ? CST1 : CST2): Don't use build_nonstandard_type, just convert to type. Use boolean_true_node instead of constant_boolean_node (true, boolean_type_node). Formatting fixes.
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