On Wed, 12 Feb 2014 18:06:56 -0500, Tony Harminc wrote: > >..., but some instructions are allowed by the architecture to >recognize access exceptions in the case where no data is stored, e.g. >STCM with a zero mask. > Ouch! How does this work when the 4 bytes that might be accessed span a page boundary so that some might be accessible and others not? If no bytes selected by the mask are inaccessible, there should be no access exception *except* that for recognizing access exceptions the behavior is may be as if one (only?) byte were selected, even if the mask is zero? Ouch! Or may recognizing access exceptions be performed as if the mask were B'1111'? Ouch!
Is recognizing an access exception performed according to rules different from recognizing a protection exception when a page might be accessible but not writable? -- gil ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
