[llvm] [ORC] Add UUID support to MachOPlatform::HeaderOptions. (PR #191873)

[Lang Hames via llvm-commits]

https://github.com/lhames created https://github.com/llvm/llvm-project/pull/191873

MachOPlatform::HeaderOptions now includes an optional UUID field. If set, this will be used to build an LC_UUID load command for the JITDylib's MachO header.

No testcase: MachOPlatform construction requires the ORC runtime, which we can't require in LLVM regression or unit tests. In the future we should test this through the ORC runtime.

>From 6768502e3fe3aefd81a64ff5cc751103f5f1303a Mon Sep 17 00:00:00 2001
From: Lang Hames <lhames at gmail.com>
Date: Tue, 14 Apr 2026 04:45:22 +1000
Subject: [PATCH] [ORC] Add UUID support to MachOPlatform::HeaderOptions.

MachOPlatform::HeaderOptions now includes an optional UUID field. If set, this
will be used to build an LC_UUID load command for the JITDylib's MachO header.

No testcase: MachOPlatform construction requires the ORC runtime, which we
can't require in LLVM regression or unit tests. In the future we should test
this through the ORC runtime.
---
 llvm/include/llvm/ExecutionEngine/Orc/MachOBuilder.h  | 5 +++++
 llvm/include/llvm/ExecutionEngine/Orc/MachOPlatform.h | 5 +++++
 llvm/lib/ExecutionEngine/Orc/MachOPlatform.cpp        | 3 +++
 3 files changed, 13 insertions(+)

diff --git a/llvm/include/llvm/ExecutionEngine/Orc/MachOBuilder.h b/llvm/include/llvm/ExecutionEngine/Orc/MachOBuilder.h
index 3d833348b9b2d..2af2dfed1c41a 100644
--- a/llvm/include/llvm/ExecutionEngine/Orc/MachOBuilder.h
+++ b/llvm/include/llvm/ExecutionEngine/Orc/MachOBuilder.h
@@ -88,6 +88,11 @@ struct MachOBuilderLoadCommand<MachO::LC_UUID>
       : MachOBuilderLoadCommandImplBase<MachO::LC_UUID>() {
     memcpy(uuid, UUID, sizeof(uuid));
   }
+
+  MachOBuilderLoadCommand(const std::array<uint8_t, 16> &UUID)
+      : MachOBuilderLoadCommandImplBase<MachO::LC_UUID>() {
+    memcpy(uuid, UUID.data(), sizeof(uuid));
+  }
 };
 
 template <MachO::LoadCommandType LCType>
diff --git a/llvm/include/llvm/ExecutionEngine/Orc/MachOPlatform.h b/llvm/include/llvm/ExecutionEngine/Orc/MachOPlatform.h
index 753c322a9121f..944f099c38b61 100644
--- a/llvm/include/llvm/ExecutionEngine/Orc/MachOPlatform.h
+++ b/llvm/include/llvm/ExecutionEngine/Orc/MachOPlatform.h
@@ -20,7 +20,9 @@
 #include "llvm/ExecutionEngine/Orc/Shared/ExecutorAddress.h"
 #include "llvm/Support/Compiler.h"
 
+#include <array>
 #include <future>
+#include <optional>
 #include <thread>
 #include <vector>
 
@@ -88,6 +90,9 @@ class LLVM_ABI MachOPlatform : public Platform {
     /// List of LC_BUILD_VERSIONs.
     std::vector<BuildVersionOpts> BuildVersions;
 
+    /// Optional UUID. If set, this will be used to add an LC_UUID command.
+    std::optional<std::array<uint8_t, 16>> UUID;
+
     HeaderOptions() = default;
     HeaderOptions(Dylib D) : IDDylib(std::move(D)) {}
   };
diff --git a/llvm/lib/ExecutionEngine/Orc/MachOPlatform.cpp b/llvm/lib/ExecutionEngine/Orc/MachOPlatform.cpp
index f8bdb6e541df1..410f972589531 100644
--- a/llvm/lib/ExecutionEngine/Orc/MachOPlatform.cpp
+++ b/llvm/lib/ExecutionEngine/Orc/MachOPlatform.cpp
@@ -1765,6 +1765,9 @@ jitlink::Block &createHeaderBlock(MachOPlatform &MOP,
   else
     B.template addLoadCommand<MachO::LC_ID_DYLIB>(JD.getName(), 0, 0, 0);
 
+  if (Opts.UUID)
+    B.template addLoadCommand<MachO::LC_UUID>(*Opts.UUID);
+
   for (auto &BV : Opts.BuildVersions)
     B.template addLoadCommand<MachO::LC_BUILD_VERSION>(
         BV.Platform, BV.MinOS, BV.SDK, static_cast<uint32_t>(0));