[compiler-rt] Create a combined compiler-rt builtin bitcode for SPIRV64 target (PR #214149)

[via llvm-commits]

https://github.com/jinge90 updated https://github.com/llvm/llvm-project/pull/214149

>From d5da7915086770b9cf0371d9264459adb7d46e36 Mon Sep 17 00:00:00 2001
From: jinge90 <ge.jin at intel.com>
Date: Wed, 5 Aug 2026 16:04:19 +0800
Subject: [PATCH] Create a combined compiler-rt builtin bitcode for SPIRV64
 target

Signed-off-by: jinge90 <ge.jin at intel.com>
---
 compiler-rt/lib/builtins/CMakeLists.txt | 32 +++++++++++++++++++++++++
 1 file changed, 32 insertions(+)

diff --git a/compiler-rt/lib/builtins/CMakeLists.txt b/compiler-rt/lib/builtins/CMakeLists.txt
index aca50c78aa147..357fb2238a9d6 100644
--- a/compiler-rt/lib/builtins/CMakeLists.txt
+++ b/compiler-rt/lib/builtins/CMakeLists.txt
@@ -1168,6 +1168,38 @@ else ()
       get_compiler_rt_output_dir(${arch} BUILTIN_LIB_OUTPUT_DIR)
       set_output_name(BUILTIN_LIB_OUTPUT_NAME clang_rt.builtins ${arch})
       file(WRITE "${BUILTIN_LIB_OUTPUT_DIR}/${BUILTIN_LIB_OUTPUT_NAME}.sources.txt" "${${arch}_SOURCES}")
+
+      # For spirv64, produce a combined bitcode file alongside the static archive.
+      # -mlink-builtin-bitcode expects raw LLVM IR and cannot unpack a static archive,
+      # so we use llvm-link to merge the archive members into a single .bc file.
+      if("${arch}" MATCHES "^spirv64")
+        find_program(LLVM_LINK llvm-link
+          PATHS ${LLVM_TOOLS_BINARY_DIR}
+          NO_DEFAULT_PATH)
+        if(LLVM_LINK)
+          set(SPIRV64_BC_OUTPUT "${BUILTIN_LIB_OUTPUT_DIR}/lib${BUILTIN_LIB_OUTPUT_NAME}.bc")
+          add_custom_command(
+            OUTPUT "${SPIRV64_BC_OUTPUT}"
+            COMMAND "${LLVM_LINK}"
+                    "$<TARGET_FILE:clang_rt.builtins-spirv64>"
+                    -o "${SPIRV64_BC_OUTPUT}"
+            DEPENDS clang_rt.builtins-${arch}
+            COMMENT "Linking lib${BUILTIN_LIB_OUTPUT_NAME}.bc"
+            VERBATIM)
+          add_custom_target(clang_rt.builtins-spirv64-bc ALL
+            DEPENDS "${SPIRV64_BC_OUTPUT}")
+          add_dependencies(builtins clang_rt.builtins-spirv64-bc)
+          get_compiler_rt_install_dir(${arch} BUILTIN_INSTALL_DIR)
+          install(FILES "${SPIRV64_BC_OUTPUT}"
+                  DESTINATION "${BUILTIN_INSTALL_DIR}"
+                  COMPONENT builtins)
+        else()
+          message(WARNING
+            "llvm-link not found (LLVM_TOOLS_BINARY_DIR='${LLVM_TOOLS_BINARY_DIR}'); "
+            "skipping libclang_rt.builtins.bc for spirv64")
+        endif()
+      endif()
+
       cmake_pop_check_state()
     endif ()
   endforeach ()