From: terje.mathisen@nospicedham.tmsw.no   
      
   Kerr-Mudd, John wrote:   
   > On Tue, 23 Nov 2021 07:40:41 +0100   
   > wolfgang kern  wrote:   
   >   
   >> On 22/11/2021 20:16, Nicolae Nasturica posted:   
   >> ---   
   >>>>> Can someone please explain why MASM is reporting "Jump out of   
   >>>>> range by 130(bytes)   
   >>   
   >> because the range is a signed byte (+127..-128) and because MASM   
   >> don't know about long CC-instructions (perhaps it knows with hint   
   >> "long"):   
   >>   
   >> 0F 8x 43 21  jmp cc rel+4+2143   
   >   
   > There are also the unconditional jmps   
   > E9 xx xx     jmp   
   > EB xx        jmp near[/short]   
   > has the same +127-128 range, but means a slightly increased jmp   
   > forward, ability as the jmp is from the address of the next op code.   
   >>   
   >> versus short:   
   >> 7x 12        jmp cc rel+2+12   
   >>   
   >> both variants use signed values relative to the address after the   
   >> jump. __   
   >> wolfgang   
   >>   
   >   
   > It might be useful to someone here; but Alexei answered Vassone's   
   > question back in 2000.   
      
   2000?   
      
   You young wippersnappers! :-)   
      
   This particular issue came up regularly even before the 808x was   
   invented, the solution was always the same, i.e. use some other method   
   for the far jump and a short branch past this code to avoid it.   
      
   TASM (maybe around 1986?) had options to handle this automatically: By   
   starting with the long jump macro at every branch location and then make   
   one or a couple of passes, nearly all of them could be converted to the   
   short form.   
      
   By starting with the long form   
      
   Long branch on Greater to target   
      jle $+3   
      jmp target   
      
   and then for each target checking the offset and if in the -128 to +127   
   range, convert to the two-byte form, no previously converted branch can   
   go out of range, so the process is stable. After 2 or 3 iterations   
   you'll probably find that either all of them are now short, or that no   
   more can be converted.   
      
   I think there were other assemblers which did the same trick.   
      
   Terje   
      
      
   --   
   -    
   "almost all programming can be viewed as an exercise in caching"   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)