svn commit: r357965 - projects/clang1000-import/contrib/llvm-project/libunwind/src

[Dimitry Andric]

Author: dim
Date: Sat Feb 15 15:03:26 2020
New Revision: 357965
URL: https://svnweb.freebsd.org/changeset/base/357965

Log:
  Merge commit 221c5af4e from llvm git (by Nico Weber):
  
    Fix a -Wbitwise-conditional-parentheses warning in
    _LIBUNWIND_ARM_EHABI libunwind builds
  
    ```
    src/UnwindCursor.hpp:1344:51: error: operator '?:' has lower precedence than '|'; '|' will be evaluated first [-Werror,-Wbitwise-conditional-parentheses]
      _info.flags = isSingleWordEHT ? 1 : 0 | scope32 ? 0x2 : 0;  // Use enum?
  					~~~~~~~~~~~ ^
    src/UnwindCursor.hpp:1344:51: note: place parentheses around the '|' expression to silence this warning
      _info.flags = isSingleWordEHT ? 1 : 0 | scope32 ? 0x2 : 0;  // Use enum?
  						    ^
  					(          )
    src/UnwindCursor.hpp:1344:51: note: place parentheses around the '?:' expression to evaluate it first
      _info.flags = isSingleWordEHT ? 1 : 0 | scope32 ? 0x2 : 0;  // Use enum?
  						    ^
  					    (                )
    ```
  
    But `0 |` is a no-op for either of those two interpretations, so I
    think what was meant here was
  
    ```
      _info.flags = (isSingleWordEHT ? 1 : 0) | (scope32 ? 0x2 : 0);  // Use enum?
    ```
  
    Previously, if `isSingleWordEHT` was set, bit 2 would never be set.
    Now it is. From what I can tell, the only thing that checks these
    bitmask is ProcessDescriptors in Unwind-EHABI.cpp, and that only
    cares about bit 1, so in practice this shouldn't have much of an
    effect.
  
    Differential Revision: https://reviews.llvm.org/D73890
  
  This fixes the above errors when building libunwind for arm variants.

Modified:
  projects/clang1000-import/contrib/llvm-project/libunwind/src/UnwindCursor.hpp

Modified: projects/clang1000-import/contrib/llvm-project/libunwind/src/UnwindCursor.hpp
==============================================================================
--- projects/clang1000-import/contrib/llvm-project/libunwind/src/UnwindCursor.hpp	Sat Feb 15 14:58:40 2020	(r357964)
+++ projects/clang1000-import/contrib/llvm-project/libunwind/src/UnwindCursor.hpp	Sat Feb 15 15:03:26 2020	(r357965)
@@ -1353,7 +1353,8 @@ bool UnwindCursor<A, R>::getInfoFromEHABISection(
 
   // If the high bit is set, the exception handling table entry is inline inside
   // the index table entry on the second word (aka |indexDataAddr|). Otherwise,
-  // the table points at an offset in the exception handling table (section 5 EHABI).
+  // the table points at an offset in the exception handling table (section 5
+  // EHABI).
   pint_t exceptionTableAddr;
   uint32_t exceptionTableData;
   bool isSingleWordEHT;
@@ -1452,7 +1453,7 @@ bool UnwindCursor<A, R>::getInfoFromEHABISection(
   _info.unwind_info = exceptionTableAddr;
   _info.lsda = lsda;
   // flags is pr_cache.additional. See EHABI #7.2 for definition of bit 0.
-  _info.flags = isSingleWordEHT ? 1 : 0 | scope32 ? 0x2 : 0;  // Use enum?
+  _info.flags = (isSingleWordEHT ? 1 : 0) | (scope32 ? 0x2 : 0);  // Use enum?
 
   return true;
 }