Help for a MACRO

[jj2007]

.if bh & 80h

:t

[frktons]

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.if  btx(ebx, 15)

It's readable for my n00b's sight.

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.if ebx & (1 SHL 15) 8)

It's NOT readable for my n00b's sight.
In other words [sequence of instructions] what we do?
(1 SHL 15) is not a common syntax, I didn'know
it existed. What are we shifting left? Probably ebx, before
a compare, but exactly what this line does?  ::)

.if bh & 80h

This is readable as well.  :icon_eek: 

[jj2007]

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.if ebx & (1 SHL 15) 8)

It's NOT readable for my n00b's sight.
In other words [sequence of instructions] what we do?
(1 SHL 15) is not a common syntax, I didn'know
it existed. What are we shifting left?

The "1", actually.
(1 shl 15) is 32768 or 100000000000000b, same as 2^15

I don't like the shl syntax either, but Masm doesn't understand 2^15 :(

[frktons]

The "1", actually.
(1 shl 15) is 32768 or 100000000000000b, same as 2^15

I don't like the shl syntax either, but Masm doesn't understand 2^15 :(

I have to confess I suspected it.

I didn't find in Intel manuals this possibility to shift a constant, is it
a feature of MASM?

[MichaelW]

Yes, the shifting is done by the MASM "preprocessor" and the result is encoded as a constant.

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.if ebx & (1 SHL 15)
.endif


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00401000 F7C300800000           test    ebx,8000h
00401006 7400                   jz      loc_00401008


[frktons]

Yes, the shifting is done by the MASM "preprocessor" and the result is encoded as a constant.

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.if ebx & (1 SHL 15)
.endif


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00401000 F7C300800000           test    ebx,8000h
00401006 7400                   jz      loc_00401008


Thanks Michael, good to know I can do so many things with
MACROS, preprocessor engine, and so on.

Something I could use is:

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P2_15  EQU 1 SHL 15 ; The Power of 2 ^ 15

....

.if  ebx & P2_15
     jmp ItsThere
.endif



at least it should be doable, and quite readable for my eyes.  :lol: