Commits on Dec 8, 2023

1. Fix x86 SSE4.1 ptestnzc …

   `(op & mask) == 0` and `(op & mask) == mask` need each to be calculated for the whole vector.
   
   For example, given
   * `op = [0b100, 0b010]`
   * `mask = [0b100, 0b110]`
   
   The correct result would be:
   * `op & mask = [0b100, 0b010]`
   Comparisons are done on the vector as a whole:
   * `all_zero = (op & mask) == [0, 0] = false`
   * `masked_set = (op & mask) == mask = false`
   * `!all_zero && !masked_set = true`
   
   The previous method:
   `op & mask = [0b100, 0b010]`
   Comparisons are done element-wise:
   * `all_zero = (op & mask) == [0, 0] = [true, true]`
   * `masked_set = (op & mask) == mask = [true, false]`
   * `!all_zero && !masked_set = [true, false]`
   After folding with AND, the final result would be `false`, which is incorrect.

   

   eduardosm committed Dec 8, 2023
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