Am Mittwoch, 26. August 2020, 15:35:45 CEST schrieb anthony:
I try to use amd64 assembly with addressing mode base with displacement,
scaled index and scaled index with displacement gforth i.e.
mov (%rdx,%rcx,1),%rax
mov (%rdx,%rcx,4),%rax
mov 40(%rdx,%rcx,4),%rax
I installed gforth from git version 0.7.9_20200820 on linux opensuse
15.1 64 bit.
I included this code to test:
ABI-CODE A ( -- )
500 # AX MOV \ AX := 500
DX AX MOV \ AX := DX
200 AX MOV \ AX := (200)
DX ) AX MOV \ AX := (DX)
40 DX D) AX MOV \ AX := (DX + 40)
\ DX CX I) AX MOV \ AX := (DX + CX)
\ DX CX *4 I) AX MOV \ AX := (DX + CX * 4) *1/2/4/8
\ 40 DX CX *4 DI) AX MOV \ AX := (DX + CX * 4 + 40)
DI AX MOV
RET
END-CODE
Compiling any of the now commented three lines results in an "invalid
memory address" error.
Maybe I am using an invalid syntax? Thought this was the correct syntax
after reading asm.fs
Every help is very much appreciated.
Anthony
This here works:
abi-code test ok 1
ax cx *4 i) dx mov ok 1
3 ax cx *8 di) dx mov ok 1
ret ok 1
end-code
see test
ABI-Code test
7F38B25582B0: mov rdx,[rax][rcx*4]
7F38B25582B4: mov rdx,$03[rax][rcx*8]
7F38B25582B9: ret
end-code
Your example doesn't work, though. Looks like some storage is not cleaned
after finishing with one instruction. Your syntax is ok.