[TUHS] Memory management in Dennis Ritchie's C Compiler

Noel Chiappa jnc at mercury.lcs.mit.edu
Thu Aug 27 01:59:08 AEST 2020

    > From: John Cowan

    > That's always true on the PDP-11 and Vax ... because the processor
    > architecture (which has pre-increment and post-decrement instructions,
    > but not their counterparts)

After Doug's message, I carefull re-read this, and I'm not sure it's correct?
The PDP-11 has pre-decrement and post-increment, not the other way around (as
above) - unless I'm misunderstanding what you meant by those terms?

That's why:

	*p++ = 0;

turns (if p is in R2) into

	CLR	(R2)+

R2 is used, and then incremented after it has been used.


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