Function eval_lanewise_fadd_f32x2 

pub fn eval_lanewise_fadd_f32x2(a: u64, b: u64) -> u64

Packed-float add for F32×2 (two IEEE-754 f32 lanes in one 64-bit word, lane 0 low) — the SPEC: each lane an independent scalar f32 add. A NaN/Inf/subnormal in one lane cannot perturb the other; SAT cannot bitblast IEEE arithmetic, so simd_tile_lock certifies this by per-lane bit-exactness + a cross-lane non-contamination battery (the way the scalar float lane is already proven). This is the model the parallel fp32 FPU lanes realize in silicon.