Gelu afp fix (#5039)

src/layer/vulkan/shader/gelu.comp

@@ -64,9 +64,9 @@ void main()
     // y = 0.5x * (1 + tanh(sqrt(2/Pi) * (x + 0.044715x^3)))
 
 #if NCNN_moltenvk
-    v = 0.5f * v * (1.0f + afp(tanh(float(0.79788452f * (v + 0.044715f * v * v * v)))));
+    v = afp(0.5f) * v * (afp(1.0f) + afp(tanh(float(afp(0.79788452f) * (v + afp(0.044715f) * v * v * v)))));
 #else
-    v = 0.5f * v * (1.0f + tanh(0.79788452f * (v + 0.044715f * v * v * v)));
+    v = afp(0.5f) * v * (afp(1.0f) + tanh(afp(0.79788452f) * (v + afp(0.044715f) * v * v * v)));
 #endif
 
 #if NCNN_image_shader

src/layer/vulkan/shader/gelu_pack4.comp

@@ -64,9 +64,9 @@ void main()
     // y = 0.5x * (1 + tanh(sqrt(2/Pi) * (x + 0.044715x^3)))
 
 #if NCNN_moltenvk
-    v = 0.5f * v * (1.0f + afpvec4(tanh(vec4(0.79788452f * (v + 0.044715f * v * v * v)))));
+    v = afpvec4(0.5f) * v * (afpvec4(1.0f) + afpvec4(tanh(vec4(afpvec4(0.79788452f) * (v + afpvec4(0.044715f) * v * v * v)))));
 #else
-    v = 0.5f * v * (1.0f + tanh(0.79788452f * (v + 0.044715f * v * v * v)));
+    v = afpvec4(0.5f) * v * (afpvec4(1.0f) + tanh(afpvec4(0.79788452f) * (v + afpvec4(0.044715f) * v * v * v)));
 #endif
 
 #if NCNN_image_shader

src/layer/vulkan/shader/gelu_pack8.comp

@@ -65,11 +65,11 @@ void main()
     // y = 0.5x * (1 + tanh(sqrt(2/Pi) * (x + 0.044715x^3)))
     
 #if NCNN_moltenvk
-    v[0] = 0.5f * v[0] * (1.0f + afpvec4(tanh(vec4(0.79788452f * (v[0] + 0.044715f * v[0] * v[0] * v[0])))));
-    v[1] = 0.5f * v[1] * (1.0f + afpvec4(tanh(vec4(0.79788452f * (v[1] + 0.044715f * v[1] * v[1] * v[1])))));
+    v[0] = afpvec4(0.5f) * v[0] * (afpvec4(1.0f) + afpvec4(tanh(vec4(afpvec4(0.79788452f) * (v[0] + afpvec4(0.044715f) * v[0] * v[0] * v[0])))));
+    v[1] = afpvec4(0.5f) * v[1] * (afpvec4(1.0f) + afpvec4(tanh(vec4(afpvec4(0.79788452f) * (v[1] + afpvec4(0.044715f) * v[1] * v[1] * v[1])))));
 #else
-    v[0] = 0.5f * v[0] * (1.0f + tanh(0.79788452f * (v[0] + 0.044715f * v[0] * v[0] * v[0])));
-    v[1] = 0.5f * v[1] * (1.0f + tanh(0.79788452f * (v[1] + 0.044715f * v[1] * v[1] * v[1])));
+    v[0] = afpvec4(0.5f) * v[0] * (afpvec4(1.0f) + tanh(afpvec4(0.79788452f) * (v[0] + afpvec4(0.044715f) * v[0] * v[0] * v[0])));
+    v[1] = afpvec4(0.5f) * v[1] * (afpvec4(1.0f) + tanh(afpvec4(0.79788452f) * (v[1] + afpvec4(0.044715f) * v[1] * v[1] * v[1])));
 #endif
 
 #if NCNN_image_shader