[Bug tree-optimization/120031] Fails to pattern match ctz from DeBruijn

[fxue at os dot amperecomputing.com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120031

Feng Xue <fxue at os dot amperecomputing.com> changed:

           What    |Removed                     |Added
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                 CC|                            |fxue at os dot 
amperecomputing.com

--- Comment #6 from Feng Xue <fxue at os dot amperecomputing.com> ---
Also fail to capture the pattern if we change type of DeBruijnBytePos[32] to
long 

  static const unsigned long DeBruijnBytePos[32] = {0, 1, 28, 2, 29, 14, 24, 3,
            30, 22, 20, 15, 25, 17, 4, 8,
            31, 27, 13, 23, 21, 19, 16, 7,
            26, 12, 18, 6, 11, 5, 10, 9};
  return DeBruijnBytePos[((unsigned int) ((val & -(int) val) * 0x077CB531U)) >>
27];