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Re: [PATCH, Fix PR 31098] a*C == b*C is not foldded to a == b with --fast-math/floating point


... I think swap_tree_comparison is only correct here if OP is a
multiplicative operator.  (And offhand I don't remember what modulus
does here.)

Pranav> +int f3(float a, float b)
Pranav> +{
Pranav> +  return a*-10 >= b*-10;
Pranav> +}

E.g., what if this read: return (a + -10) >= (b + -10) ?
(a + -10 >= (b + -10) becomes (a - 10 ) >= (b - 10) before it enters fold_comparison and so real_isneg (cst0)
returns false and swap_tree_comparison doesnt come into the picture.

cheers!
Pranav

Pranav Bhandarkar
GNU Tools
Celunite, Inc.
(www.celunite.com)
+91-98220 82881



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