From 49c1b2ee83100c9cbff901dd03d3d8d248790612 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Christian=20K=C3=B6gler?= <ck3d@gmx.de>
Date: Wed, 20 May 2026 13:52:09 +0200
Subject: [PATCH] onnxruntime: add CoreML support on Darwin

Add optional CoreML execution provider for macOS builds. Fetches
coremltools, FP16, and psimd as external sources via CMake's
FetchContent. Tests are disabled when CoreML is enabled.
---
 pkgs/by-name/on/onnxruntime/package.nix | 36 ++++++++++++++++++++++++-
 1 file changed, 35 insertions(+), 1 deletion(-)

diff --git a/pkgs/by-name/on/onnxruntime/package.nix b/pkgs/by-name/on/onnxruntime/package.nix
index 08514fbd6c7c..0bfb17de83b2 100644
--- a/pkgs/by-name/on/onnxruntime/package.nix
+++ b/pkgs/by-name/on/onnxruntime/package.nix
@@ -25,6 +25,7 @@
   cudaSupport ? config.cudaSupport,
   ncclSupport ? cudaSupport && cudaPackages.nccl.meta.available,
   rocmSupport ? config.rocmSupport,
+  coremlSupport ? stdenv.hostPlatform.isDarwin,
   withFullProtobuf ? false,
   cudaPackages ? { },
   rocmPackages,
@@ -80,6 +81,30 @@ let
     hash = "sha256-YqgzCyNywixebpHGx16tUuczmFS5pjCz5WjR89mv9eI=";
   };
 
+  coremltools-src = fetchFromGitHub {
+    name = "coremltools-src";
+    owner = "apple";
+    repo = "coremltools";
+    tag = "7.1";
+    hash = "sha256-kajQFHpl+4UK6fp+rM8TP0GiqIFYXPVFc2x1p19rBSw=";
+  };
+
+  fp16-src = fetchFromGitHub {
+    name = "fp16-src";
+    owner = "Maratyszcza";
+    repo = "FP16";
+    rev = "0a92994d729ff76a58f692d3028ca1b64b145d91";
+    hash = "sha256-m2d9bqZoGWzuUPGkd29MsrdscnJRtuIkLIMp3fMmtRY=";
+  };
+
+  psimd-src = fetchFromGitHub {
+    name = "psimd-src";
+    owner = "Maratyszcza";
+    repo = "psimd";
+    rev = "072586a71b55b7f8c584153d223e95687148a900";
+    hash = "sha256-lV+VZi2b4SQlRYrhKx9Dxc6HlDEFz3newvcBjTekupo=";
+  };
+
   isCudaJetson = cudaSupport && cudaPackages.flags.isJetsonBuild;
 in
 effectiveStdenv.mkDerivation (finalAttrs: {
@@ -263,6 +288,7 @@ effectiveStdenv.mkDerivation (finalAttrs: {
     (lib.cmakeBool "onnxruntime_USE_CUDA" cudaSupport)
     (lib.cmakeBool "onnxruntime_USE_NCCL" (cudaSupport && ncclSupport))
     (lib.cmakeBool "onnxruntime_USE_MIGRAPHX" rocmSupport)
+    (lib.cmakeBool "onnxruntime_USE_COREML" coremlSupport)
     (lib.cmakeBool "onnxruntime_ENABLE_LTO" (!cudaSupport || cudaPackages.cudaOlder "12.8"))
   ]
   ++ lib.optionals pythonSupport [
@@ -284,6 +310,12 @@ effectiveStdenv.mkDerivation (finalAttrs: {
     # Incompatible with packaged version, far too slow to build vendored version
     (lib.cmakeBool "onnxruntime_USE_COMPOSABLE_KERNEL" false)
     (lib.cmakeBool "onnxruntime_USE_COMPOSABLE_KERNEL_CK_TILE" false)
+  ]
+  ++ lib.optionals coremlSupport [
+    (lib.cmakeFeature "FETCHCONTENT_SOURCE_DIR_COREMLTOOLS" "${coremltools-src}")
+    (lib.cmakeFeature "FETCHCONTENT_SOURCE_DIR_FP16" "${fp16-src}")
+    (lib.cmakeFeature "FETCHCONTENT_SOURCE_DIR_PSIMD" "${psimd-src}")
+    (lib.cmakeFeature "CMAKE_POLICY_VERSION_MINIMUM" "3.5") # needed for psimd
   ];
 
   env =
@@ -314,6 +346,7 @@ effectiveStdenv.mkDerivation (finalAttrs: {
     !(
       cudaSupport
       || rocmSupport
+      || coremlSupport
       # cross-compiled test binaries can't execute on the build platform
       || (effectiveStdenv.hostPlatform != effectiveStdenv.buildPlatform)
       || builtins.elem effectiveStdenv.buildPlatform.system [
@@ -337,7 +370,8 @@ effectiveStdenv.mkDerivation (finalAttrs: {
     install -m644 -Dt $out/include \
       ../include/onnxruntime/core/framework/provider_options.h \
       ../include/onnxruntime/core/providers/cpu/cpu_provider_factory.h \
-      ../include/onnxruntime/core/session/onnxruntime_*.h
+      ../include/onnxruntime/core/session/onnxruntime_*.h \
+      ../include/onnxruntime/core/providers/coreml/coreml_provider_factory.h
   '';
 
   # See comments in `cudaPackages.nccl`