[PGO][Offload] Hide GPU entrypoint on Darwin

Author: EthanLuisMcDonough

clang/lib/Driver/ToolChains/Darwin.cpp

@@ -1481,15 +1481,11 @@ void Darwin::addProfileRTLibs(const ArgList &Args,
   // If we have a symbol export directive and we're linking in the profile
   // runtime, automatically export symbols necessary to implement some of the
   // runtime's functionality.
-  if (hasExportSymbolDirective(Args)) {
-    if (ForGCOV) {
-      addExportedSymbol(CmdArgs, "___gcov_dump");
-      addExportedSymbol(CmdArgs, "___gcov_reset");
-      addExportedSymbol(CmdArgs, "_writeout_fn_list");
-      addExportedSymbol(CmdArgs, "_reset_fn_list");
-    } else {
-      addExportedSymbol(CmdArgs, "___llvm_write_custom_profile");
-    }
+  if (hasExportSymbolDirective(Args) && ForGCOV) {
+    addExportedSymbol(CmdArgs, "___gcov_dump");
+    addExportedSymbol(CmdArgs, "___gcov_reset");
+    addExportedSymbol(CmdArgs, "_writeout_fn_list");
+    addExportedSymbol(CmdArgs, "_reset_fn_list");
   }
 
   // Align __llvm_prf_{cnts,bits,data} sections to the maximum expected page

compiler-rt/lib/profile/InstrProfilingFile.c

@@ -1273,13 +1273,11 @@ COMPILER_RT_VISIBILITY int __llvm_profile_set_file_object(FILE *File,
   return 0;
 }
 
-int __llvm_write_custom_profile(const char *Target,
-                                const __llvm_profile_data *DataBegin,
-                                const __llvm_profile_data *DataEnd,
-                                const char *CountersBegin,
-                                const char *CountersEnd, const char *NamesBegin,
-                                const char *NamesEnd,
-                                const uint64_t *VersionOverride) {
+COMPILER_RT_GPU_ENTRYPOINT int __llvm_write_custom_profile(
+    const char *Target, const __llvm_profile_data *DataBegin,
+    const __llvm_profile_data *DataEnd, const char *CountersBegin,
+    const char *CountersEnd, const char *NamesBegin, const char *NamesEnd,
+    const uint64_t *VersionOverride) {
   int ReturnValue = 0, FilenameLength, TargetLength;
   char *FilenameBuf, *TargetFilename;
   const char *Filename;

compiler-rt/lib/profile/InstrProfilingPort.h

@@ -43,8 +43,10 @@
 
 #if defined(__APPLE__)
 #define COMPILER_RT_SEG "__DATA,"
+#define COMPILER_RT_GPU_ENTRYPOINT COMPILER_RT_VISIBILITY
 #else
 #define COMPILER_RT_SEG ""
+#define COMPILER_RT_GPU_ENTRYPOINT
 #endif
 
 #ifdef _MSC_VER