[compiler-rt] d0797e6 - Re-apply "[CMake][compiler-rt][AArch64] Avoid preprocessing LSE builtins separately"

[Raul Tambre via llvm-commits]

Author: Raul Tambre
Date: 2020-12-14T16:45:48+02:00
New Revision: d0797e62fa8a73ad75dcaca7c0e1a71c2001c855

URL: https://github.com/llvm/llvm-project/commit/d0797e62fa8a73ad75dcaca7c0e1a71c2001c855
DIFF: https://github.com/llvm/llvm-project/commit/d0797e62fa8a73ad75dcaca7c0e1a71c2001c855.diff

LOG: Re-apply "[CMake][compiler-rt][AArch64] Avoid preprocessing LSE builtins separately"

aa772fc85e0f526615c78b9c3979c2be945a754c (D92530) has landed fixing Apple builds.
Previous quick-fix d9697c2e6b153ac7dc40a69450d9b672f71b1029 (D93198) included in this commit.

Invoking the preprocessor ourselves is fragile and would require us to replicate CMake's handling of definitions, compiler flags, etc for proper compatibility.
In my toolchain builds this notably resulted in a bunch of warnings from unused flags as my CMAKE_C_FLAGS includes CPU-specific optimization options.
Notably this part was already duplicating the logic for VISIBILITY_HIDDEN define.

Instead, symlink the files and set the proper set of defines on each.
This should also be faster as we avoid invoking the compiler multiple times.

Fixes https://llvm.org/PR48494

Differential Revision: https://reviews.llvm.org/D93211

Added: 
    

Modified: 
    compiler-rt/cmake/Modules/CompilerRTDarwinUtils.cmake
    compiler-rt/lib/builtins/CMakeLists.txt
    compiler-rt/lib/builtins/aarch64/lse.S

Removed: 
    


################################################################################
diff  --git a/compiler-rt/cmake/Modules/CompilerRTDarwinUtils.cmake b/compiler-rt/cmake/Modules/CompilerRTDarwinUtils.cmake
index f6689c2e79ad..456a8dcda59f 100644
--- a/compiler-rt/cmake/Modules/CompilerRTDarwinUtils.cmake
+++ b/compiler-rt/cmake/Modules/CompilerRTDarwinUtils.cmake
@@ -395,7 +395,9 @@ macro(darwin_add_builtin_libraries)
   set(CMAKE_CXX_FLAGS "")
   set(CMAKE_ASM_FLAGS "")
 
-  set(PROFILE_SOURCES ../profile/InstrProfiling 
+  append_string_if(COMPILER_RT_HAS_ASM_LSE " -DHAS_ASM_LSE" CFLAGS)
+
+  set(PROFILE_SOURCES ../profile/InstrProfiling
                       ../profile/InstrProfilingBuffer
                       ../profile/InstrProfilingPlatformDarwin
                       ../profile/InstrProfilingWriter

diff  --git a/compiler-rt/lib/builtins/CMakeLists.txt b/compiler-rt/lib/builtins/CMakeLists.txt
index d84f4d09e53e..5259e951dff3 100644
--- a/compiler-rt/lib/builtins/CMakeLists.txt
+++ b/compiler-rt/lib/builtins/CMakeLists.txt
@@ -509,31 +509,24 @@ set(aarch64_SOURCES
 )
 
 # Generate outline atomics helpers from lse.S base
-set(CUSTOM_FLAGS ${CMAKE_C_FLAGS})
-if(NOT ANDROID)
-  append_list_if(COMPILER_RT_HAS_VISIBILITY_HIDDEN_FLAG -DVISIBILITY_HIDDEN CUSTOM_FLAGS)
-endif()
-append_list_if(COMPILER_RT_HAS_ASM_LSE -DHAS_ASM_LSE CUSTOM_FLAGS)
-string(REPLACE " " "\t" CUSTOM_FLAGS "${CUSTOM_FLAGS}")
 set(OA_HELPERS_DIR "${CMAKE_CURRENT_BINARY_DIR}/outline_atomic_helpers.dir")
-file(MAKE_DIRECTORY ${OA_HELPERS_DIR})
+file(MAKE_DIRECTORY "${OA_HELPERS_DIR}")
 
 foreach(pat cas swp ldadd ldclr ldeor ldset)
   foreach(size 1 2 4 8 16)
     foreach(model 1 2 3 4)
       if(pat STREQUAL "cas" OR NOT size STREQUAL "16")
-        set(helper_asm ${OA_HELPERS_DIR}/outline_atomic_${pat}${size}_${model}.S)
+        set(helper_asm "${OA_HELPERS_DIR}/outline_atomic_${pat}${size}_${model}.S")
         add_custom_command(
           OUTPUT ${helper_asm}
-          COMMAND ${CMAKE_C_COMPILER} -E ${CUSTOM_FLAGS} -DL_${pat} -DSIZE=${size} -DMODEL=${model}
-                  ${CMAKE_CURRENT_SOURCE_DIR}/aarch64/lse.S -o ${helper_asm}
-          DEPENDS aarch64/lse.S assembly.h
+          COMMAND ${CMAKE_COMMAND} -E create_symlink "${CMAKE_CURRENT_SOURCE_DIR}/aarch64/lse.S" "${helper_asm}"
         )
-        set_source_files_properties(${helper_asm} PROPERTIES GENERATED TRUE)
-        set(aarch64_SOURCES
-          ${aarch64_SOURCES}
-          ${helper_asm}
+        set_source_files_properties("${helper_asm}"
+          PROPERTIES
+          COMPILE_DEFINITIONS "L_${pat};SIZE=${size};MODEL=${model}"
+          INCLUDE_DIRECTORIES "${CMAKE_CURRENT_SOURCE_DIR}"
         )
+        list(APPEND aarch64_SOURCES "${helper_asm}")
       endif()
     endforeach(model)
   endforeach(size)
@@ -687,6 +680,8 @@ else ()
     append_list_if(COMPILER_RT_HAS_VISIBILITY_HIDDEN_FLAG VISIBILITY_HIDDEN BUILTIN_DEFS)
   endif()
 
+  append_list_if(COMPILER_RT_HAS_ASM_LSE HAS_ASM_LSE BUILTIN_DEFS)
+
   foreach (arch ${BUILTIN_SUPPORTED_ARCH})
     if (CAN_TARGET_${arch})
       # For ARM archs, exclude any VFP builtins if VFP is not supported

diff  --git a/compiler-rt/lib/builtins/aarch64/lse.S b/compiler-rt/lib/builtins/aarch64/lse.S
index 770f098b7cf1..7a9433fd89cf 100644
--- a/compiler-rt/lib/builtins/aarch64/lse.S
+++ b/compiler-rt/lib/builtins/aarch64/lse.S
@@ -2,7 +2,7 @@
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 
-#include "../assembly.h"
+#include "assembly.h"
 
 // Out-of-line LSE atomics helpers. Ported from libgcc library.
 // N = {1, 2, 4, 8}