[libclc] [libclc] Append file_specific_compile_options after ARG_COMPILE_FLAGS (PR #139871)

[Wenju He via cfe-commits]

https://github.com/wenju-he created https://github.com/llvm/llvm-project/pull/139871

This enables file_specific_compile_options to take precedence over ARG_COMPILE_FLAGS. For example, if we add -fno-slp-vectorize to COMPILE_OPTIONS of a file, the behavior changes as follows:
* Before this PR: -fno-slp-vectorize is overwritten by -O3, resulting in SLP vectorizer remaining enabled.
* After this PR: -fno-slp-vectorize overwrites -O3, effectively disabling SLP vectorizer.

>From f1d805ed5467d6ca3b8162e4cc5baddf2961f26d Mon Sep 17 00:00:00 2001
From: Wenju He <wenju.he at intel.com>
Date: Wed, 14 May 2025 02:58:35 -0700
Subject: [PATCH] [libclc] Append file_specific_compile_options after
 ARG_COMPILE_FLAGS

This enables file_specific_compile_options to take precedence over
ARG_COMPILE_FLAGS. For example, if we add -fno-slp-vectorize to
COMPILE_OPTIONS of a file, the behavior changes as follows:
* Before this PR: -fno-slp-vectorize is overwritten by -O3, resulting in
  SLP vectorizer remaining enabled.
* After this PR: -fno-slp-vectorize overwrites -O3, effectively
  disabling SLP vectorizer.
---
 libclc/cmake/modules/AddLibclc.cmake | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/libclc/cmake/modules/AddLibclc.cmake b/libclc/cmake/modules/AddLibclc.cmake
index 3be2bf231eb30..d00b16a899664 100644
--- a/libclc/cmake/modules/AddLibclc.cmake
+++ b/libclc/cmake/modules/AddLibclc.cmake
@@ -284,8 +284,9 @@ function(add_libclc_builtin_set)
       TRIPLE ${ARG_TRIPLE}
       INPUT ${input_file}
       OUTPUT ${output_file}
-      EXTRA_OPTS -fno-builtin -nostdlib "${file_specific_compile_options}"
-        "${ARG_COMPILE_FLAGS}" -I${CMAKE_CURRENT_SOURCE_DIR}/${file_dir}
+      EXTRA_OPTS -fno-builtin -nostdlib "${ARG_COMPILE_FLAGS}"
+        "${file_specific_compile_options}"
+        -I${CMAKE_CURRENT_SOURCE_DIR}/${file_dir}
       DEPENDENCIES ${input_file_dep}
     )
     list( APPEND compile_tgts ${tgt} )