[compiler-rt] [compiler-rt] Add option to build standalone AArch64 SME builtins shared library (PR #72545)

[Benjamin Maxwell via llvm-commits]

https://github.com/MacDue created https://github.com/llvm/llvm-project/pull/72545

This adds a `COMPILER_RT_BUILD_STANDALONE_AARCH64_SME_RUNTIME` CMake option, which allows building the AArch64 SME builtins into a standalone shared library. This allows loading the builtins into the MLIR Arm SME integration tests via the `-shared-libs` flag on the `mlir-cpu-runner`.

>From 35d0e876f90fa1380c5ca556ec361bd219e7340a Mon Sep 17 00:00:00 2001
From: Benjamin Maxwell <benjamin.maxwell at arm.com>
Date: Thu, 16 Nov 2023 18:03:10 +0000
Subject: [PATCH] [compiler-rt] Add option to build standalone AArch64 SME
 builtins shared library

This adds a COMPILER_RT_BUILD_STANDALONE_AARCH64_SME_RUNTIME CMake
option whichs allows building the AArch64 SME builtins into a standalone
shared library. This allows loading the builtins into the MLIR Arm SME
tests, via the `-shared-libs` flag on the `mlir-cpu-runner`.
---
 compiler-rt/lib/builtins/CMakeLists.txt | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/compiler-rt/lib/builtins/CMakeLists.txt b/compiler-rt/lib/builtins/CMakeLists.txt
index 069d33bfd3d309b..d6189dd67a18afe 100644
--- a/compiler-rt/lib/builtins/CMakeLists.txt
+++ b/compiler-rt/lib/builtins/CMakeLists.txt
@@ -553,9 +553,23 @@ set(aarch64_SOURCES
   aarch64/fp_mode.c
 )
 
-if(COMPILER_RT_HAS_ASM_SME AND (COMPILER_RT_HAS_AUXV OR COMPILER_RT_BAREMETAL_BUILD))
+option(COMPILER_RT_BUILD_STANDALONE_AARCH64_SME_RUNTIME
+  "Build standalone shared aarch64 SME runtime library."
+  OFF)
+
+if (COMPILER_RT_HAS_ASM_SME AND (COMPILER_RT_HAS_AUXV OR COMPILER_RT_BAREMETAL_BUILD))
   list(APPEND aarch64_SOURCES aarch64/sme-abi.S aarch64/sme-abi-init.c)
   message(STATUS "AArch64 SME ABI routines enabled")
+  if (COMPILER_RT_BUILD_STANDALONE_AARCH64_SME_RUNTIME)
+    message(STATUS "Standalone AArch64 SME runtime enabled")
+    add_custom_target(builtins-standalone-aarch64-sme-runtime)
+    add_compiler_rt_runtime(arm_sme_rt
+        SHARED
+        ARCHS "aarch64"
+        SOURCES aarch64/sme-abi.S aarch64/sme-abi-init.c
+        PARENT_TARGET builtins-standalone-aarch64-sme-runtime)
+    add_dependencies(compiler-rt builtins-standalone-aarch64-sme-runtime)
+  endif()
 else()
   message(STATUS "AArch64 SME ABI routines disabled")
 endif()