[libclc] [libclc] Skip opt command if opt_flags is empty (PR #130882)

[Wenju He via cfe-commits]

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@@ -342,22 +342,32 @@ function(add_libclc_builtin_set)
 
   set( builtins_opt_lib_tgt builtins.opt.${ARG_ARCH_SUFFIX} )
 
-  # Add opt target
-  add_custom_command( OUTPUT ${builtins_opt_lib_tgt}.bc
-    COMMAND ${opt_exe} ${ARG_OPT_FLAGS} -o ${builtins_opt_lib_tgt}.bc
-      ${builtins_link_lib}
-    DEPENDS ${opt_target} ${builtins_link_lib} ${builtins_link_lib_tgt}
-  )
-  add_custom_target( ${builtins_opt_lib_tgt}
-    ALL DEPENDS ${builtins_opt_lib_tgt}.bc
-  )
+  if( ${ARG_OPT_FLAGS} STREQUAL "" )
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wenju-he wrote:

just curious would this Pr unifies the this code and avoid the early exit and duplicate code for prepare target?

https://github.com/llvm/llvm-project/pull/130882