Use libcxx's default rune table with the Musl C library.

Summary:
Also, there are no exported character type tables from Musl so we have to
Fallback to the standard functions. This reduces the number of libcxx's
test-suite failures down to ~130 for MIPS. Most of the remaining failures
come from the atomics (due to the lack of 8-byte atomic-ops in MIPS32) and
thread tests.

Reviewers: mclow.lists, EricWF, dalias, jroelofs

Subscribers: tberghammer, danalbert, srhines, cfe-commits

Differential Revision: http://reviews.llvm.org/D14926

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@253972 91177308-0d34-0410-b5e6-96231b3b80d8

include/__config

@@ -804,7 +804,7 @@ extern "C" void __sanitizer_annotate_contiguous_container(
 #define _LIBCPP_HAS_NO_STDOUT
 #endif
 
-#if defined(__ANDROID__) || defined(__CloudABI__)
+#if defined(__ANDROID__) || defined(__CloudABI__) || defined(_LIBCPP_HAS_MUSL_LIBC)
 #define _LIBCPP_PROVIDES_DEFAULT_RUNE_TABLE
 #endif
 

include/__locale

@@ -361,7 +361,7 @@ public:
     typedef __uint32_t mask;
 # elif defined(__FreeBSD__)
     typedef unsigned long mask;
-# elif defined(__EMSCRIPTEN__) || defined(__NetBSD__) || defined(_LIBCPP_HAS_MUSL_LIBC)
+# elif defined(__EMSCRIPTEN__) || defined(__NetBSD__)
     typedef unsigned short mask;
 # endif
     static const mask space  = _CTYPE_S;
@@ -407,12 +407,8 @@ public:
 # define _LIBCPP_CTYPE_MASK_IS_COMPOSITE_PRINT
 # define _LIBCPP_CTYPE_MASK_IS_COMPOSITE_ALPHA
 # define _LIBCPP_CTYPE_MASK_IS_COMPOSITE_XDIGIT
-#else
-#if defined(_LIBCPP_HAS_MUSL_LIBC)
-    typedef unsigned short mask;
 #else
     typedef unsigned long mask;
-#endif
     static const mask space  = 1<<0;
     static const mask print  = 1<<1;
     static const mask cntrl  = 1<<2;
@@ -634,7 +630,7 @@ public:
 #endif
     _LIBCPP_ALWAYS_INLINE const mask* table() const  _NOEXCEPT {return __tab_;}
     static const mask* classic_table()  _NOEXCEPT;
-#if defined(__GLIBC__) || defined(__EMSCRIPTEN__) || defined(_LIBCPP_HAS_MUSL_LIBC)
+#if defined(__GLIBC__) || defined(__EMSCRIPTEN__)
     static const int* __classic_upper_table() _NOEXCEPT;
     static const int* __classic_lower_table() _NOEXCEPT;
 #endif