[Bug tree-optimization/24021] VRP does not work with floating points

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=24021

--- Comment #27 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Aldy Hernandez <aldyh@gcc.gnu.org>:

https://gcc.gnu.org/g:9d96a286992a0fd9ecdd6a58cd9a413c8c49f477

commit r13-3812-g9d96a286992a0fd9ecdd6a58cd9a413c8c49f477
Author: Aldy Hernandez <aldyh@redhat.com>
Date:   Thu Oct 13 08:14:16 2022 +0200

    [PR24021] Implement PLUS_EXPR range-op entry for floats.

    This is the range-op entry for floating point PLUS_EXPR.  It's the
    most intricate range entry we have so far, because we need to keep
    track of rounding and target FP formats.  This will be the last FP
    entry I commit, mostly to avoid disturbing the tree any further, and
    also because what we have so far is enough for a solid VRP.

    So far we track NANs and signs correctly.  We also handle relationals
    (symbolics and numeric), both ordered and unordered, ABS_EXPR and
    NEGATE_EXPR which are used to fold __builtin_isinf, and __builtin_sign
    (__builtin_copysign is coming up).  All in all, I think this provide
    more than enough for basic VRP on floats, as well as provide a basis
    to flesh out the rest if there's interest.

    My goal with this entry is to provide a template for additional binary
    operators, as they tend to follow a similar pattern: handle NANs, do
    the arithmetic while keeping track of rounding, and adjust for NAN.  I
    may abstract the general parts as we do for irange's fold_range and
    wi_fold.

            PR tree-optimization/24021

    gcc/ChangeLog:

            * range-op-float.cc (propagate_nans): New.
            (frange_nextafter): New.
            (frange_arithmetic): New.
            (class foperator_plus): New.
            (floating_op_table::floating_op_table): Add PLUS_EXPR entry.

    gcc/testsuite/ChangeLog:

            * gcc.dg/tree-ssa/vrp-float-plus.c: New test.