Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!uflorida!haven!rutgers!rochester!pt.cs.cmu.edu!andrew.cmu.edu!jk3k+
From: jk3k+@andrew.cmu.edu (Joe Keane)
Newsgroups: comp.arch
Subject: Re: Endian reversing MOVEs
Message-ID: <MXvZBhy00W428s8WI0@andrew.cmu.edu>
Date: 7 Feb 89 02:24:45 GMT
References: <759@atanasoff.cs.iastate.edu>
Organization: Mathematics, Carnegie Mellon, Pittsburgh, PA
Lines: 16
In-Reply-To: <759@atanasoff.cs.iastate.edu>

John Hascall writes:
> ;
> ;     Move and Reverse Endian-ness Longword
> ;
>       .macro  MREL    src,dst
>       PUSHL   src                     ; stack source operand
>       MOVB    0(SP),-(SP)             ; re-stack HI byte
>       MOVB    2(SP),-(SP)             ; re-stack HI-MID byte
>       MOVB    4(SP),-(SP)             ; re-stack LO-MID byte
>       MOVB    6(SP),-(SP)             ; re-stack LO byte
>       MOVL    (SP)+,dst               ; pop it into destination operand
>       TSTL    (SP)+                   ; clear stack, set cond code
>       .endm

That's 11 memory references for something which has nothing to do with memory.
It only takes 6 instructions (0 memory references) on the RT.