[libc-commits] [PATCH] D104897: [libc] Use __builtin_ctzll instead of __builtin_ctzl in elements_x86.h.

[Siva Chandra via Phabricator via libc-commits]

sivachandra created this revision.
sivachandra added a reviewer: gchatelet.
Herald added subscribers: libc-commits, ecnelises, tschuett.
Herald added a project: libc-project.
sivachandra requested review of this revision.

__builtin_ctzl takes an unsigned long argument which need not be 64-bit
long on all platforms. Using __builtin_ctzll, which takes an unsigned
long long argument, ensures that 64-bit values will be handled on a
wider range of platforms.

Without this change, the test corresponding to M512 fails in Windows.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D104897

Files:
  libc/src/string/memory_utils/elements_x86.h


Index: libc/src/string/memory_utils/elements_x86.h
===================================================================
--- libc/src/string/memory_utils/elements_x86.h
+++ libc/src/string/memory_utils/elements_x86.h
@@ -46,7 +46,7 @@
   }
 
   static int CharDiff(const char *a, const char *b, uint64_t mask) {
-    const size_t diff_index = __builtin_ctzl(mask);
+    const size_t diff_index = __builtin_ctzll(mask);
     const int ca = (unsigned char)a[diff_index];
     const int cb = (unsigned char)b[diff_index];
     return ca - cb;


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D104897.354433.patch
Type: text/x-patch
Size: 538 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/libc-commits/attachments/20210625/5285c2f5/attachment.bin>