[worked around]How to use adr instruction in AArch64?

[pik33]

I tried to get an address of a label in Raspbian 64bit on RPi4 using Lazarus 2.10/fpc 3.3.1

Code: [Select]


function test:pointer;

label aaa;
var a:pointer;

begin

     asm
aaa: adr x1,aaa
     str x1,a
     end;

result:=a;

end;


and got "invalid reference syntax" compiler error in line labelled "aaa:"

What I did wrong?  How to use adr instruction here? In the standalone assembler as the syntax adr reg,label is ok. 

[pik33]

Partially solved.

Syntax that works is is adr Xn,#imm

Incompatible with all A64 assembly manuals (use adr reg,label); compatible with the raw instruction code

The label position in code can be translated to #imm manually but it can be broken with changes in the code.

[PascalDragon]

I can't test it right now (I can test more once I'm at home in the evening), but the following might work (considering that I used similar code in the Rtti unit):

Code: Pascal  [Select][+][-]

1. asm
2. .LAddr:
3.   adr x1, .LAddr
4.   str x1, a
5. end;

This is a local assembly-only label in contrast to a Pascal label.

[pik33]

I can't test it right now (I can test more once I'm at home in the evening), but the following might work (considering that I used similar code in the Rtti unit):

Code: Pascal  [Select][+][-]

1. asm
2. .LAddr:
3.   adr x1, .LAddr
4.   str x1, a
5. end;

This is a local assembly-only label in contrast to a Pascal label.

This didn't work with the same error message.