[NFC][hwasan][Fuchsia] Instead wrap contents of InitLoadedGlobals with if constexpr (!SANITIZER_FUCHSIA)

[leonardchan]

Summary

This prevents spamming the build log with unused InitLoadedGlobals when building fuchsia runtimes.

[mcgrathr]

lgtm

compiler-rt/lib/hwasan/hwasan.cpp

static bool InitializeSingleGlobal(const hwasan_global &global) {
   uptr full_granule_size = RoundDownTo(global.size(), 16);
   TagMemoryAligned(global.addr(), full_granule_size, global.tag());
   if (global.size() % 16)
     TagMemoryAligned(global.addr() + full_granule_size, 16, global.size() % 16);
   return false;
 }
 
 static void InitLoadedGlobals() {
+  // Fuchsia's libc provides a hook (__sanitizer_module_loaded) that runs on
+  // the startup path which calls into __hwasan_library_loaded on all
+  // initially loaded modules, so explicitly registering the globals here
+  // isn't needed.
+  if constexpr (!SANITIZER_FUCHSIA) {
     dl_iterate_phdr(
         [](dl_phdr_info *info, size_t /* size */, void * /* data */) -> int {
           for (const hwasan_global &global : HwasanGlobalsFor(
                    info->dlpi_addr, info->dlpi_phdr, info->dlpi_phnum))
             InitializeSingleGlobal(global);
           return 0;
         },
         nullptr);
   }
+}
 
 // Prepare to run instrumented code on the main thread.
 static void InitInstrumentation() {
   if (hwasan_instrumentation_inited) return;
 
   InitializeOsSupport();
 
   if (!InitShadow()) {
__attribute__((constructor(0))) void __hwasan_init() {
 
   __sanitizer_set_report_path(common_flags()->log_path);
 
   AndroidTestTlsSlot();
 
   DisableCoreDumperIfNecessary();
 
   InitInstrumentation();
-  if constexpr (!SANITIZER_FUCHSIA) {
-    // Fuchsia's libc provides a hook (__sanitizer_module_loaded) that runs on
-    // the startup path which calls into __hwasan_library_loaded on all
-    // initially loaded modules, so explicitly registering the globals here
-    // isn't needed.
-    InitLoadedGlobals();
-  }
 
   // Needs to be called here because flags()->random_tags might not have been
   // initialized when InitInstrumentation() was called.
   GetCurrentThread()->EnsureRandomStateInited();
 
   SetPrintfAndReportCallback(AppendToErrorMessageBuffer);
   // This may call libc -> needs initialized shadow.
   AndroidLogInit();