SIMD: Fix compile error by using MaxLanes instead of Lanes for array size

seiko2plus · seiko2plus · commit c7884f0f7a99 · 2025-04-17T16:39:28.000+02:00
Replace hn::Lanes(f64) with hn::MaxLanes(f64) when defining the index array
  size to fix error C2131: "expression did not evaluate to a constant". This error
  occurs because Lanes() isn't always constexpr compatible, especially with
  scalable vector extensions. MaxLanes() provides a compile-time constant value
  suitable for static array allocation and should be used with non-scalable SIMD
  extensions when defining fixed-size arrays.
diff --git a/numpy/_core/src/umath/loops_hyperbolic.dispatch.cpp.src b/numpy/_core/src/umath/loops_hyperbolic.dispatch.cpp.src
@@ -393,7 +393,7 @@ simd_tanh_f64(const double *src, npy_intp ssrc, double *dst, npy_intp sdst, npy_
         vec_f64 b, c0, c1, c2, c3, c4, c5, c6, c7, c8, c9, c10, c11, c12, c13, c14, c15, c16;
         if constexpr(hn::MaxLanes(f64) == 2){
             vec_f64 e0e1_0, e0e1_1;
-            uint64_t index[hn::Lanes(f64)];
+            uint64_t index[hn::MaxLanes(f64)];
             hn::StoreU(idx, u64, index);
 
             /**begin repeat
diff --git a/numpy/_core/src/umath/loops_trigonometric.dispatch.cpp b/numpy/_core/src/umath/loops_trigonometric.dispatch.cpp
@@ -186,7 +186,7 @@ simd_sincos_f32(const float *src, npy_intp ssrc, float *dst, npy_intp sdst,
                           "larger than 256 bits.");
             simd_maski = ((uint8_t *)&simd_maski)[0];
 #endif
-            float NPY_DECL_ALIGNED(NPY_SIMD_WIDTH) ip_fback[hn::Lanes(f32)];
+            float NPY_DECL_ALIGNED(NPY_SIMD_WIDTH) ip_fback[hn::MaxLanes(f32)];
             hn::Store(x_in, f32, ip_fback);
 
             // process elements using libc for large elements
