ASSUME is evil

[oex]

Used it once and it breaks in macros right?

Any way for a macro to push an assume state?

x macro arg:REQ
mov edi, arg <---- Cant, assume:nothing and cant restore in macro as assume struct is unknown
endm

.code
assume edi:PTR sStruct
x var
<---- can not restore assume here in macro?
assume edi:nothing

[dedndave]

don't use ASSUME   :P

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        mov     eax,[edi].sStruct.MemberName

[dedndave]

come to think of it - there should be no problem
ASSUME is an assembler directive
it is applied in a "serial" manner to the source text
so, if your macros are defined at the beginning of the program, or in an INC file,
then ASSUME should only apply to that macro

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        ASSUME Something:Something

;macro code

        ASSUME Something:Nothing
;
;
;
;
;
        ASSUME Something:SomethingElse

;macro call

;SomethingElse is still assumed, here

applying ASSUME inside the macro may be a different story   :P

[dedndave]

oops

[qWord]

you can use PUSH/POPCONTEXT to save the current ASUMME-settings:

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mymacro macro
PUSHCONTEXT ASSUMES
assume whatever
...
POPCONTEXT ASSUMES
endm

[dedndave]

i thought that only applied to the ASSUME for segment registers

[Vortex]

Another example :

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mov eax,[esi+IMAGE_NT_HEADERS.OptionalHeader.DataDirectory.VirtualAddress+SIZEOF IMAGE_DATA_DIRECTORY]

[oex]

Another example :

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mov eax,[esi+IMAGE_NT_HEADERS.OptionalHeader.DataDirectory.VirtualAddress+SIZEOF IMAGE_DATA_DIRECTORY]

yes I use this.... [esi].IMAGE_NT_HEADERS.OptionalHeader.....

I thought I'd post as I had once used assume in all my code, it errored on compile and I knew no work-around

you can use PUSH/POPCONTEXT to save the current ASUMME-settings:

Code Select Expand

mymacro macro
PUSHCONTEXT ASSUMES
assume whatever
...
POPCONTEXT ASSUMES
endm

nice 1

i thought that only applied to the ASSUME for segment registers

I didnt test :lol

[dedndave]

well - that's the wording used in the masm manual
however, it could be a carry-over from previous versions of masm
i.e., the text in the manual could be out of date

You can save the contexts inside macros with PUSHCONTEXT and
POPCONTEXT. The options for these keywords are:

Option Description
ASSUMES Saves segment register information
RADIX Saves current default radix
LISTING Saves listing and CREF information
CPU Saves current CPU and processor
ALL All of the above

[jj2007]

well - that's the wording used in the masm manual
however, it could be a carry-over from previous versions of masm
i.e., the text in the manual could be out of date

MSDN still says segment register assumes

But let's just test it... try commenting out the P*CONTEXT inside the macro:

Code Select Expand

include \masm32\include\masm32rt.inc

mypt MACRO ptArg
LOCAL tmp$, is
PUSHCONTEXT assumes
  Assume esi:PTR POINT
  tmp$ CATSTR <mov eax, [esi.>, <ptArg>, <]>
  % echo tmp$
  tmp$
POPCONTEXT assumes
  EXITM <eax>
ENDM

.code
TheRect RECT <12, 34, 56, 78>
ThePoint POINT <88, 99>

start:
Assume esi:PTR RECT
mov esi, offset TheRect
print str$([esi.left]), ", "
print str$([esi.right]), 13, 10
mov esi, offset ThePoint
print str$(mypt(x)), ", "
print str$(mypt(y)), 13, 10
mov esi, offset TheRect
print str$([esi.left]), ", "
print str$([esi.right]), 13, 10
exit

end start