Getting away with coding murder, have you ever seen code like this?

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AvidStudent

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Example Snip:

CODE

mov esi, eax ; Update source index.
mov [edi].spEnd, esi ; Store current source index into destination (end.)

cmp ecx, dwSliceNumber ; See if this is the slice requested.
jne @B ; if not requested slice, re-enter loop.

sub eax, [edi].spBegin ; Calculate destination (length.)

mov [edi].spLen, eax ; Store destination (length.)

.IF eax == 0 ; This is a zero width element
inc [edi].spLen ; Zero size would not be useful for allocation of an item
; and may raise an error. EAX is still zero.

mov [edi].spFlag, ZTSLICEFLAG[ZTSLICE_ZERO_WIDTH]

.endif

This is some code from my ZTSS SDK v 3.2 B current release is 2.0 A. Why do I say "Getting away with coding murder" ? This particular procedure has no local variables, checks for and flags six different errors, contains a loop, calls two different procedures (which both require two parameters) and only uses four registers directly. (if you count eax.)

If you are interested in learning these high level addressing techniques download the ZTSS SDK from the projects source code section here @ WinASM.net

If we are going to share source code, we should all write "better" code. No?

P.S. the code pointed to by EDI is a MASM STRUCT. ZTSLICEFLAG is an ENUM.

JimG

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I don't see anything unusual about the snippet you posted, other than it's really messy. And it does none of the things you mentioned. ?

CODE

mov esi,eax ; Update source index.
mov [edi].spEnd,esi ; Store current source index into destination (end.)
cmp ecx,dwSliceNumber; See if this is the slice requested.
jne @B ; if not requested slice, re-enter loop.
sub eax,[edi].spBegin; Calculate destination (length.)
mov [edi].spLen, eax ; Store destination (length.)
.IF eax == 0 ; This is a zero width element
inc [edi].spLen ; Zero size would not be useful for allocation of an item
; and may raise an error. EAX is still zero.
mov [edi].spFlag, ZTSLICEFLAG[ZTSLICE_ZERO_WIDTH]
.endif

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