dxc marks compares fast, so `lo == lo ? lo : -inf` was deleted under default flags and an
overflowed form ranged to NaN on HLSL targets. The guard now tests (asuint(lo) & 0x7fffffff)
> 0x7f800000, in HLSL, the Unity copy, math.Affine.cs and the regenerated CultMath.glsl.
dxc 1.9.0.5402 -T ps_6_0 default flags: before, no fcmp/select/and in the af_range body;
after, and/icmp ugt/select to +-inf for both endpoints (also under -Gis).
AffineRangeMirrorMatchesCSharpBitForBitAtTheFloatExtremes pins the mirror at zero to the
float maximum, infinities and NaN components.
Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
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