From f7f0dcadd3b2aca4c0bcd03a96e11c617cf69fc2 Mon Sep 17 00:00:00 2001
From: Sai Praveen Bangaru <31557731+saipraveenb25@users.noreply.github.com>
Date: Wed, 26 Oct 2022 22:21:29 -0400
Subject: Adding a differentiable standard library (#2465)

---
 source/slang/diff.meta.slang | 63 ++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 61 insertions(+), 2 deletions(-)

(limited to 'source/slang/diff.meta.slang')

diff --git a/source/slang/diff.meta.slang b/source/slang/diff.meta.slang
index f314e0487..ea204c839 100644
--- a/source/slang/diff.meta.slang
+++ b/source/slang/diff.meta.slang
@@ -5,7 +5,7 @@
 syntax __differentiate_jvp : JVPDerivativeModifier;
 
 // Custom JVP Function reference
-__attributeTarget(FuncDecl)
+__attributeTarget(FunctionDeclBase)
 attribute_syntax [__custom_jvp(function)]   : CustomJVPAttribute;
 
 /// Interface to denote types as differentiable.
@@ -39,7 +39,7 @@ extension float : IDifferentiable
     [__unsafeForceInlineEarly]
     static Differential zero()
     {
-        return 0.f;
+        return float(0.f);
     }
 
     [__unsafeForceInlineEarly]
@@ -151,3 +151,62 @@ struct __DifferentialPair
         return p();
     }
 };
+
+typealias IDFloat = IFloat & IDifferentiable;
+
+namespace dstd
+{
+    // Natural Exponent
+    __generic<T : IDFloat>
+    __target_intrinsic(hlsl)
+    __target_intrinsic(glsl)
+    __target_intrinsic(cuda, "$P_exp($0)")
+    __target_intrinsic(cpp, "$P_exp($0)")
+    __target_intrinsic(spirv_direct, "12 resultType resultId glsl450 27 _0")
+    [__custom_jvp(d_exp<T>)]
+    T exp(T x);
+
+    __generic<T : IDFloat>
+    __DifferentialPair<T> d_exp(__DifferentialPair<T> dpx)
+    {
+        return __DifferentialPair<T>(
+            exp(dpx.p()),
+            T.dmul(exp(dpx.p()), dpx.d()));
+    }
+
+    // Sine
+    __generic<T : IDFloat>
+    __target_intrinsic(hlsl)
+    __target_intrinsic(glsl)
+    __target_intrinsic(cuda, "$P_sin($0)")
+    __target_intrinsic(cpp, "$P_sin($0)")
+    __target_intrinsic(spirv_direct, "12 resultType resultId glsl450 13 _0")
+    [__custom_jvp(d_sin<T>)]
+    T sin(T x);
+
+    __generic<T : IDFloat>
+    __DifferentialPair<T> d_sin(__DifferentialPair<T> dpx)
+    {
+        return __DifferentialPair<T>(
+            sin(dpx.p()),
+            T.dmul(cos(dpx.p()), dpx.d()));
+    }
+
+    // Cosine
+    __generic<T : IDFloat>
+    __target_intrinsic(hlsl)
+    __target_intrinsic(glsl)
+    __target_intrinsic(cuda, "$P_cos($0)")
+    __target_intrinsic(cpp, "$P_cos($0)")
+    __target_intrinsic(spirv_direct, "12 resultType resultId glsl450 14 _0")
+    [__custom_jvp(d_cos<T>)]
+    T cos(T x);
+
+    __generic<T : IDFloat>
+    __DifferentialPair<T> d_cos(__DifferentialPair<T> dpx)
+    {
+        return __DifferentialPair<T>(
+            cos(dpx.p()),
+            T.dmul(-sin(dpx.p()), dpx.d()));
+    }
+};
-- 
cgit v1.2.3