syntax issues

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tthsqe

Joined: 20 May 2009
Posts: 767

tthsqe 19 Sep 2009, 05:31

What am I doing wrong? / What is the best way to do this?

Code:

f:      push    rbp
        sub     rsp,8*4
        mov     rbp,rsp

  Frequency = rbp+8*0
  StartTime = rbp+8*1
  EndTime   = rbp+8*2
  LocVar    = rbp+8*3

        invoke  QueryPerformanceFrequency, addr Frequency
        invoke  QueryPerformanceCounter, addr StartTime
        ...

        add     rsp,8*4
        pop     rbp
        ret

19 Sep 2009, 05:31

Fanael

Joined: 03 Jul 2009
Posts: 168

Fanael 19 Sep 2009, 08:01

Code:

foo = sth

declares an assembly-time constant or variable. Value of rbp register of course isn't known at compile time, so this is invalid.
Use equ:

Code:

Frequency equ rbp+8*0
StartTime equ rbp+8*1
;and so on

19 Sep 2009, 08:01

roxaz

Joined: 27 Jul 2008
Posts: 25

roxaz 19 Sep 2009, 08:02

how about using struct?

Code:

include '%fasminc%\win64a.inc'

struct Structure
  Frequency dq ?
  StartTime dq ?
  EndTime   dq ?
  LocVar    dq ?
ends

section '.text' code readable executable

  start:
        push    rbp
        sub     rsp,8*4
        mov     rbp,rsp

        invoke  QueryPerformanceFrequency, [rbp+Structure.Frequency]
        invoke  QueryPerformanceCounter, [rbp+Structure.StartTime]


        add     rsp,8*4
        pop     rbp
        ret

19 Sep 2009, 08:02

LocoDelAssembly
Your code has a bug

Joined: 06 May 2005
Posts: 4624
Location: Argentina

LocoDelAssembly 19 Sep 2009, 16:33

Or this:

Code:

  start:

  virtual at rbp - .locals_size
      .Frequency dq ?
      .StartTime dq ?
      .EndTime   dq ?
      .LocVar    dq ?

  .locals_size = ($ - $$ + 7) and -8
  end virtual

        push    rbp
        mov     rbp, rsp
        sub     rsp, .locals_size


        invoke  QueryPerformanceFrequency, addr .Frequency
        invoke  QueryPerformanceCounter, addr .StartTime


        mov     rsp, rbp
        pop     rbp
        ret

[edit]Replaced code with one using rbp in a more "canonical" way.
[edit2]Parameters modified to the correct ones.[/edit2]

Last edited by LocoDelAssembly on 19 Sep 2009, 16:54; edited 2 times in total

19 Sep 2009, 16:33

tthsqe

Joined: 20 May 2009
Posts: 767

tthsqe 19 Sep 2009, 16:35

thanks, I didn't know about equ.
But, the code generated for the invoke should be:

Code:

        sub     rsp,8*2
        lea     rcx,[Frequency]
        call    [QueryPerformanceFrequency]
        add     rsp,8*2

and I haven't been able to get inoke to do this

19 Sep 2009, 16:35

LocoDelAssembly
Your code has a bug

Joined: 06 May 2005
Posts: 4624
Location: Argentina

LocoDelAssembly 19 Sep 2009, 16:40

What do you get instead?

19 Sep 2009, 16:40

tthsqe

Joined: 20 May 2009
Posts: 767

tthsqe 19 Sep 2009, 16:51

revolution,
that code has the same problem in that it generates
mov rcx,[rbp+8]
When calling QueryPF, rcx should be a pointer to the stack location:
sub rsp,8*2
lea rcx,[rbp+8*n]
call [QueryPerformanceFrequency]
add rsp,8*2

19 Sep 2009, 16:51

LocoDelAssembly
Your code has a bug

Joined: 06 May 2005
Posts: 4624
Location: Argentina

LocoDelAssembly 19 Sep 2009, 16:55

Well, I guess you are talking to me actually Wink

Yes sorry, I used the wrong parameters, I edited my code again, check it if it now works.

19 Sep 2009, 16:55

tthsqe

Joined: 20 May 2009
Posts: 767

tthsqe 19 Sep 2009, 16:56

I though
invoke QueryPF, addr Frequency
would do it, but this doesn't assemble. maybe a bug in the invoke macro?

19 Sep 2009, 16:56

tthsqe

Joined: 20 May 2009
Posts: 767

tthsqe 19 Sep 2009, 17:01

Sorry! LocoDelAssembly,
With your edited code, on the first invoke line I get a
Error: invalid operand
insruction: inc addr .Frequency
source: timingtest.asm[28]
proc64,inc [5]
proc64.inc [41]

using FASM 1.68

19 Sep 2009, 17:01

LocoDelAssembly
Your code has a bug

Joined: 06 May 2005
Posts: 4624
Location: Argentina

LocoDelAssembly 19 Sep 2009, 17:33

Oh, I'm using FASM 1.69.04. "addr" is present in PROC64.INC (in the case of 32-bit programming "addr" is located in win32{a|w}x.inc instead of PROC32.INC).

However, I see that FASM 1.68 also has "addr" defined in PROC64.INC. Perhaps you are not using the very latest version? (last update: 24 Aug 2009 14:13:10 UTC)

19 Sep 2009, 17:33

tthsqe

Joined: 20 May 2009
Posts: 767

tthsqe 19 Sep 2009, 19:30

I got the new version, and it assembled it correctly.

19 Sep 2009, 19:30

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