Bug 1859954 - Use XP_DARWIN rather than XP_MACOS in PHC r=glandium

Differential Revision: https://phabricator.services.mozilla.com/D191600

memory/build/PHC.cpp

@@ -223,7 +223,7 @@ void StackTrace::Fill() {
   PNT_TIB pTib = reinterpret_cast<PNT_TIB>(NtCurrentTeb());
   void* stackEnd = static_cast<void*>(pTib->StackBase);
   FramePointerStackWalk(StackWalkCallback, kMaxFrames, this, fp, stackEnd);
-#elif defined(XP_MACOSX)
+#elif defined(XP_DARWIN)
   // This avoids MozStackWalk(), which has become unusably slow on Mac due to
   // changes in libunwind.
   //
@@ -293,7 +293,7 @@ using Delay = uint32_t;  // A time duration.
 // on ARM processors. For the latter we make an exception because the minimum
 // page size supported is 16KiB so there's no way to go below that.
 static const size_t kPageSize =
-#if defined(XP_MACOSX) && defined(__aarch64__)
+#if defined(XP_DARWIN) && defined(__aarch64__)
     16384
 #else
     4096

memory/build/test/gtest/TestPHC.cpp

@@ -382,7 +382,7 @@ TEST(PHC, TestPHCDisablingGlobal)
 // {
 void DisabledPHCExhaustionTest() {
   // PHC hardcodes the amount of allocations to track.
-#if defined(XP_MACOSX) && defined(__aarch64__)
+#if defined(XP_DARWIN) && defined(__aarch64__)
   const unsigned NUM_ALLOCATIONS = 1024;
 #else
   const unsigned NUM_ALLOCATIONS = 4096;