From be5679c5e82c3d2100633d52b26bf7851b7ae28f Mon Sep 17 00:00:00 2001
From: Vassil Vassilev <v.g.vassilev@gmail.com>
Date: Sun, 4 Aug 2024 07:59:56 +0000
Subject: [PATCH] Add builtin_exp

---
 include/clad/Differentiator/BuiltinDerivatives.h | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/include/clad/Differentiator/BuiltinDerivatives.h b/include/clad/Differentiator/BuiltinDerivatives.h
index 557274a56..c7acaa0bb 100644
--- a/include/clad/Differentiator/BuiltinDerivatives.h
+++ b/include/clad/Differentiator/BuiltinDerivatives.h
@@ -147,6 +147,11 @@ CUDA_HOST_DEVICE inline void __builtin_powf_pullback(float x, float exponent,
   *d_exponent += t.pushforward * d_y;
 }
 
+CUDA_HOST_DEVICE ValueAndPushforward<double, double>
+inline __builtin_exp_pushforward(double x, double d_x) {
+  return {__builtin_exp(x), __builtin_exp(x) * d_x};
+}
+
 // FIXME: Add the rest of the __builtin_ routines for log, sqrt, abs, etc.
 
 namespace std {