arm, neon: neon/fma support for glm_mul()

include/cglm/affine-mat.h

@@ -26,6 +26,10 @@
 #  include "simd/avx/affine.h"
 #endif
 
+#ifdef CGLM_NEON_FP
+#  include "simd/neon/affine.h"
+#endif
+
 /*!
  * @brief this is similar to glm_mat4_mul but specialized to affine transform
  *
@@ -49,6 +53,8 @@ glm_mul(mat4 m1, mat4 m2, mat4 dest) {
   glm_mul_avx(m1, m2, dest);
 #elif defined( __SSE__ ) || defined( __SSE2__ )
   glm_mul_sse2(m1, m2, dest);
+#elif defined(CGLM_NEON_FP)
+  glm_mul_neon(m1, m2, dest);
 #else
   float a00 = m1[0][0], a01 = m1[0][1], a02 = m1[0][2], a03 = m1[0][3],
         a10 = m1[1][0], a11 = m1[1][1], a12 = m1[1][2], a13 = m1[1][3],

include/cglm/simd/neon/affine.h

@@ -0,0 +1,51 @@
+/*
+ * Copyright (c), Recep Aslantas.
+ *
+ * MIT License (MIT), http://opensource.org/licenses/MIT
+ * Full license can be found in the LICENSE file
+ */
+
+#ifndef cglm_affine_neon_h
+#define cglm_affine_neon_h
+#if defined(__ARM_NEON_FP)
+
+#include "../../common.h"
+#include "../intrin.h"
+
+CGLM_INLINE
+void
+glm_mul_neon(mat4 m1, mat4 m2, mat4 dest) {
+  /* D = R * L (Column-Major) */
+
+  glmm_128 l0, l1, l2, l3, r0, r1, r2, r3, v0, v1, v2, v3;
+
+  l0 = glmm_load(m1[0]);    r0 = glmm_load(m2[0]);
+  l1 = glmm_load(m1[1]);    r1 = glmm_load(m2[1]);
+  l2 = glmm_load(m1[2]);    r2 = glmm_load(m2[2]);
+  l3 = glmm_load(m1[3]);    r3 = glmm_load(m2[3]);
+
+  v0 = vmulq_f32(glmm_splat_x(r0), l0);
+  v1 = vmulq_f32(glmm_splat_x(r1), l0);
+  v2 = vmulq_f32(glmm_splat_x(r2), l0);
+  v3 = vmulq_f32(glmm_splat_x(r3), l0);
+
+  v0 = glmm_fmadd(glmm_splat_y(r0), l1, v0);
+  v1 = glmm_fmadd(glmm_splat_y(r1), l1, v1);
+  v2 = glmm_fmadd(glmm_splat_y(r2), l1, v2);
+  v3 = glmm_fmadd(glmm_splat_y(r3), l1, v3);
+
+  v0 = glmm_fmadd(glmm_splat_z(r0), l2, v0);
+  v1 = glmm_fmadd(glmm_splat_z(r1), l2, v1);
+  v2 = glmm_fmadd(glmm_splat_z(r2), l2, v2);
+  v3 = glmm_fmadd(glmm_splat_z(r3), l2, v3);
+
+  v3 = glmm_fmadd(glmm_splat_w(r3), l3, v3);
+
+  glmm_store(dest[0], v0);
+  glmm_store(dest[1], v1);
+  glmm_store(dest[2], v2);
+  glmm_store(dest[3], v3);
+}
+
+#endif
+#endif /* cglm_affine_neon_h */

include/cglm/simd/neon/mat4.h

@@ -41,7 +41,7 @@ glm_mat4_transp_neon(mat4 m, mat4 dest) {
 CGLM_INLINE
 void
 glm_mat4_mul_neon(mat4 m1, mat4 m2, mat4 dest) {
-   /* D = R * L (Column-Major) */
+  /* D = R * L (Column-Major) */
 
   glmm_128 l0, l1, l2, l3, r0, r1, r2, r3, v0, v1, v2, v3;