[PATCH, PR83492] Fix selection of aarch64 big-endian shift parameters based on __AARCH64EB__

[Michael Weiser]

Hello,

below patch fixes PR 83492.

Running the preprocessor on any source gives various errors on
aarch64_be. These suggest that the proprocessor misidentifies token
boundaries. This can be traced to an optimized search_line_fast for
aarch64 in libcpp/lex.c which has a special provision for aarch64_be
based on the __AARCH64EB. This check can never succeed since the correct
name of the macro is __AARCH64EB__. Consequently the code for big-endian
aarch64 is never activated. As expected, changing __AARCH64EB to
__AARCH64EB__ or disabling the accelerated routine by substituting
search_line_acc_char() fixes the problem.

Thanks,
Michael

2017-12-19  Michael Weiser  <michael.wei...@gmx.de>

        PR preprocessor/83492
        * lex.c (search_line_fast) [__ARM_NEON && __ARM_64BIT_STATE]:
        Fix selection of big-endian shift parameters based on __AARCH64EB__.

Index: lex.c
===================================================================
--- lex.c       (revision 255828)
+++ lex.c       (working copy)
@@ -772,7 +772,7 @@
   const uint8x16_t repl_qm = vdupq_n_u8 ('?');
   const uint8x16_t xmask = (uint8x16_t) vdupq_n_u64 (0x8040201008040201ULL);
 
-#ifdef __AARCH64EB
+#ifdef __AARCH64EB__
   const int16x8_t shift = {8, 8, 8, 8, 0, 0, 0, 0};
 #else
   const int16x8_t shift = {0, 0, 0, 0, 8, 8, 8, 8};