Can PTEST be used to test if two registers are both zero or some other condition?
No, unless I’m missing something clever, ptest with two unknown registers is generally not useful for checking some property about both of them. (Other than obvious stuff you’d already want a bitwise-AND for, like intersection between two bitmaps). To test two registers for both being all-zero, OR them together and PTEST that against itself. ptest … Read more