Engage!

1 files changed, 27 insertions, 0 deletions

diff --git a/llama.cpp/ggml/src/ggml-vulkan/vulkan-shaders/geglu_erf.comp b/llama.cpp/ggml/src/ggml-vulkan/vulkan-shaders/geglu_erf.comp
new file mode 100644
index 0000000..759a184
--- /dev/null
+++ b/llama.cpp/ggml/src/ggml-vulkan/vulkan-shaders/geglu_erf.comp
@@ -0,0 +1,27 @@
+#version 450
+
+#include "glu_head.glsl"
+
+// based on Abramowitz and Stegun formula 7.1.26 or similar Hastings' approximation
+// ref: https://www.johndcook.com/blog/python_erf/
+const float p_erf  = 0.3275911f;
+const float a1_erf = 0.254829592f;
+const float a2_erf = -0.284496736f;
+const float a3_erf = 1.421413741f;
+const float a4_erf = -1.453152027f;
+const float a5_erf = 1.061405429f;
+
+const float SQRT_2_INV = 0.70710678118654752440084436210484f;
+
+float op(float a, float b) {
+    const float a_div_sqr2 = a * SQRT_2_INV;
+    const float sign_x = sign(a_div_sqr2);
+    const float x = abs(a_div_sqr2);
+    const float t = 1.0f / (1.0f + p_erf * x);
+    const float y = 1.0f - (((((a5_erf * t + a4_erf) * t) + a3_erf) * t + a2_erf) * t + a1_erf) * t * exp(-x * x);
+    const float erf_approx = sign_x * y;
+
+    return 0.5f * a * (1.0f + erf_approx) * b;
+}
+
+#include "glu_main.glsl"