Refer to _LIBCPP_MSVC macro where applicable

Replace preprocess conditions of defined(_MSC_VER) &&
!defined(__clang__) with defined(_LIBCPP_MSVC).  NFC.

Patch by Dave Lee!

llvm-svn: 294171
Cr-Mirrored-From: sso://chromium.googlesource.com/_direct/external/github.com/llvm/llvm-project
Cr-Mirrored-Commit: bcc85cbcde661e8bf02a5e0c385f9aa509a8dc39
diff --git a/src/exception.cpp b/src/exception.cpp
index f25041d..35a3a9a 100644
--- a/src/exception.cpp
+++ b/src/exception.cpp
@@ -138,7 +138,7 @@
 #elif defined(_LIBCPP_ABI_MICROSOFT)
     return __uncaught_exceptions();
 #else
-#   if defined(_MSC_VER) && ! defined(__clang__)
+#   if defined(_LIBCPP_MSVC)
         _LIBCPP_WARNING("uncaught_exceptions not yet implemented")
 #   else
 #       warning uncaught_exception not yet implemented
@@ -211,7 +211,7 @@
 #elif defined(__GLIBCXX__)
     reinterpret_cast<__exception_ptr::exception_ptr*>(this)->~exception_ptr();
 #else
-#   if defined(_MSC_VER) && ! defined(__clang__)
+#   if defined(_LIBCPP_MSVC)
         _LIBCPP_WARNING("exception_ptr not yet implemented")
 #   else
 #       warning exception_ptr not yet implemented
@@ -230,7 +230,7 @@
     new (reinterpret_cast<void*>(this)) __exception_ptr::exception_ptr(
         reinterpret_cast<const __exception_ptr::exception_ptr&>(other));
 #else
-#   if defined(_MSC_VER) && ! defined(__clang__)
+#   if defined(_LIBCPP_MSVC)
         _LIBCPP_WARNING("exception_ptr not yet implemented")
 #   else
 #       warning exception_ptr not yet implemented
@@ -255,7 +255,7 @@
         reinterpret_cast<const __exception_ptr::exception_ptr&>(other);
     return *this;
 #else
-#   if defined(_MSC_VER) && ! defined(__clang__)
+#   if defined(_LIBCPP_MSVC)
         _LIBCPP_WARNING("exception_ptr not yet implemented")
 #   else
 #       warning exception_ptr not yet implemented
@@ -299,7 +299,7 @@
     ptr.__ptr_ = __cxa_current_primary_exception();
     return ptr;
 #else
-#   if defined(_MSC_VER) && ! defined(__clang__)
+#   if defined(_LIBCPP_MSVC)
         _LIBCPP_WARNING( "exception_ptr not yet implemented" )
 #   else
 #       warning exception_ptr not yet implemented
@@ -321,7 +321,7 @@
 #elif defined(__GLIBCXX__)
     rethrow_exception(reinterpret_cast<__exception_ptr::exception_ptr&>(p));
 #else
-#   if defined(_MSC_VER) && ! defined(__clang__)
+#   if defined(_LIBCPP_MSVC)
         _LIBCPP_WARNING("exception_ptr not yet implemented")
 #   else
 #       warning exception_ptr not yet implemented