What calling convention is used for assembly language in Linux AMD64?
Normally the parameters go in fixed order into designated registers.

import std.stdio;
// Linux AMD64
float* test(float *x,ulong y){
	asm{
		naked;
		align 16;
		mov RAX,RDI;
		ret;
	}
}

void main(){
	float[] f=new float[16];
	writeln(&f[0]);
	float* a=test(&f[0],7);
	writeln(a);
}

If the ulong y parameter is removed from the function definition the pointer x goes into RDI as expected.  When y is added it all goes wrong. According to AMD64 the pointer should stay in RDI and the ulong go into RSI.

On Saturday, 18 August 2018 at 04:16:11 UTC, Sean O'Connor wrote:
> What calling convention is used for assembly language in Linux AMD64?
> Normally the parameters go in fixed order into designated registers.
>
> import std.stdio;
> // Linux AMD64
> float* test(float *x,ulong y){
> 	asm{
> 		naked;
> 		align 16;
> 		mov RAX,RDI;
> 		ret;
> 	}
> }
>
> void main(){
> 	float[] f=new float[16];
> 	writeln(&f[0]);
> 	float* a=test(&f[0],7);
> 	writeln(a);
> }
>
> If the ulong y parameter is removed from the function definition the pointer x goes into RDI as expected.  When y is added it all goes wrong. According to AMD64 the pointer should stay in RDI and the ulong go into RSI.

If you compile with DMD, DMD passes the arguments in reverse order. LDC and GDC use normal C calling conventions.

On Saturday, 18 August 2018 at 06:47:36 UTC, Eugene Wissner wrote:
> On Saturday, 18 August 2018 at 04:16:11 UTC, Sean O'Connor wrote:
>> What calling convention is used for assembly language in Linux AMD64?
>> Normally the parameters go in fixed order into designated registers.
>>
>> import std.stdio;
>> // Linux AMD64
>> float* test(float *x,ulong y){
>> 	asm{
>> 		naked;
>> 		align 16;
>> 		mov RAX,RDI;
>> 		ret;
>> 	}
>> }
>>
>> void main(){
>> 	float[] f=new float[16];
>> 	writeln(&f[0]);
>> 	float* a=test(&f[0],7);
>> 	writeln(a);
>> }
>>
>> If the ulong y parameter is removed from the function definition the pointer x goes into RDI as expected.  When y is added it all goes wrong. According to AMD64 the pointer should stay in RDI and the ulong go into RSI.
>
> If you compile with DMD, DMD passes the arguments in reverse order. LDC and GDC use normal C calling conventions.

You can define test() as exter(C) to force dmd to use the expected arguments order.

Okay, cool, thanks for the information.  The main reason for using D versus Java for me at the moment is that array slices allow me avoid lots of intermediate buffers that Java is forcing me to use.
Also the line count is about 2/3 of Java. Further I can directly embed any assembly language I need, rather than using JNI.
Maybe some day a version of D for graal can be written, though you would lose native assembly language.
https://github.com/oracle/graal
All I really want though is a sane low level programming language or a sane version of C.