[libc-commits] [libc] 0fa53d5 - [libc] Make `crt1.o` available to clang for GPU builds (#100599)

[via libc-commits]

Author: Joseph Huber
Date: 2024-07-26T08:51:25-05:00
New Revision: 0fa53d5183ec3c0654631d719dd6dfa7a270ca98

URL: https://github.com/llvm/llvm-project/commit/0fa53d5183ec3c0654631d719dd6dfa7a270ca98
DIFF: https://github.com/llvm/llvm-project/commit/0fa53d5183ec3c0654631d719dd6dfa7a270ca98.diff

LOG: [libc] Make `crt1.o` available to clang for GPU builds (#100599)

Summary:
We want to provide the `crt1.o` object inside of the current build so
that other projects can use it for tests. Because it's currently an
object library (as is also required for the dependencies for the
hermetic tests) this cannot be renamed and is not emitted by default.
Here we simply add an executable that emits bitcode so that CMake will
give it a name.

Added: 
    

Modified: 
    libc/startup/gpu/CMakeLists.txt

Removed: 
    


################################################################################
diff  --git a/libc/startup/gpu/CMakeLists.txt b/libc/startup/gpu/CMakeLists.txt
index 6f67fa9ff44f7..701ea63e1e2d5 100644
--- a/libc/startup/gpu/CMakeLists.txt
+++ b/libc/startup/gpu/CMakeLists.txt
@@ -26,6 +26,16 @@ function(add_startup_object name)
     PROPERTIES
       OUTPUT_NAME ${name}.o
   )
+
+  # Make an executable target of relocatable bitcode for clang if needed.
+  if(LLVM_ENABLE_PER_TARGET_RUNTIME_DIR)
+    add_executable(${fq_target_name}.exe $<TARGET_OBJECTS:${fq_target_name}>)
+    set_target_properties(${fq_target_name}.exe PROPERTIES
+      RUNTIME_OUTPUT_DIRECTORY ${LIBC_LIBRARY_DIR}
+      RUNTIME_OUTPUT_NAME ${name}.o)
+    target_link_options(${fq_target_name}.exe PRIVATE
+                        "-flto" "-Wl,--lto-emit-llvm" "-march= ")
+  endif()
 endfunction()
 
 if(EXISTS ${CMAKE_CURRENT_SOURCE_DIR}/${LIBC_TARGET_ARCHITECTURE})