load/store type auto-detection

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mike.dld

Joined: 03 Oct 2003
Posts: 235
Location: Belarus, Minsk

mike.dld 31 Dec 2011, 09:03

I've just got a feature in my mind which is nice to have (for me at least, and would simplify the code a bit), but I'm not sure if it's possible to implement it now to not break existing projects and whether it's needed at all by anyone else.
What I'm thinking about is to allow 'load' and 'store' directives to guess type of value being loaded/stored from the given location. So, for example, having a declaration of 'x dd ?' one'd be able to write 'store 0x12345678 at x' instead of 'store dword 0x12345678 at x'. Old rules would still apply if it's not possible to determine the type, and one would still be able to specify the type even if it's possible to determine it.
Alternatively, it could be acceptable to implement it so that no backward compatibility is affected by using a bit different syntax of 'store 0x12345678 at [x]' (same as one used in instructions, huh). This way, type casting would [also] be acceptable as part of location specification, such as 'store 0x12345678 at dword[x]'.
This should increase type safety while still allowing non-safe operations to be done. On the other hand, this changes default behavoir of defaulting to 'byte' type.

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31 Dec 2011, 09:03

cod3b453

Joined: 25 Aug 2004
Posts: 618

cod3b453 31 Dec 2011, 11:34

This can be achieved using macros:

Code:

struc dw val
{
        . dw val
        .typeof equ word
}

struc dd val
{
        . dd val
        .typeof equ dword
}

macro store val,id
{
        store id#.typeof val at id
}


x dd 0

store 0x12345678,x

;y dw 0
;
;store 0x10000,y

Obviously this means overriding all data constructs and the load/store and I'm not sure how this affects other macros such as proc and struct but hopefully this doesn't affect anything.

31 Dec 2011, 11:34

AsmGuru62

Joined: 28 Jan 2004
Posts: 1561
Location: Toronto, Canada

AsmGuru62 31 Dec 2011, 12:32

If something declared as DD -- it is already a DWORD, so no need for the override, the following works with no macros:

Code:

x dd ?
...
mov [x], 0x12345678

What am I missing?

31 Dec 2011, 12:32

cod3b453

Joined: 25 Aug 2004
Posts: 618

cod3b453 31 Dec 2011, 12:41

store is a compile time operation (and may be performed inside a virtual) but mov is a runtime operation.

31 Dec 2011, 12:41

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