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   Message 129,870 of 131,241   
   Brian G. Lucas to Kent Dickey   
   Re: sign/zero/garbage extension   
   09 Oct 25 16:30:38   
   
   From: bagel99@gmail.com   
      
   On 10/6/25 8:38 PM, Kent Dickey wrote:   
   [SNIP]   
   > For C and C++ code, the standard dictates that all integer operations are   
   > done with "int" precision, unless some operand is larger than int, and then   
   > do it in that precision.  So there's no real need for 8-bit and 16-bit   
   > operations to be natively by the CPU--these operations are actually done   
   > as int's already.  If you have a variable which is a byte, then assigning   
   > to that variable, and then using that variable again you will need to   
   > zero-extend, but honestly, this is not usually a performance path.  It's   
   > likely to be stored to memory instead, so no masking or sign extending   
   > should be needed.   
   >   
   [SNIP]   
   > Kent   
      
   Can you point me to the section in "the standard" which indicates   
   'all integer operations are done with "int" precision'?   
      
   What if the wording was changed to:   
   'all integer operations are done with _at least_ "int" precision',   
   e.g. one could use long.  Would that break conforming code?   
      
   Brian   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)   

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