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[davidgf]

Hi!

I've got a problem with gcc. My code block:

[WosRet]

How about using a simple label in c like:

[davidgf]

It removes too!
The problem are not the labels. The problems is that gcc removes absolutely everything after a return instruction, as it assumes I can't jump over a return.
It doesn't understand that the instruction bvt is a jump instruction!

[crazyc]

[jimparis]

I'd just write the whole function in asm if you need that much control.

[davidgf]

Anything is welcome!
But my problem is that Gcc doesn't do well with inline assembly.

Now I have:

[jimparis]

GCC does just fine with inline assembly. What you are trying to do is wrong and will not work. Read the GCC manual, which pretty clearly says:

[davidgf]

I didn't know that, none of my assembler teachers told me.
The fact is that inline assembly is weird, it could be better to use pure assembly functions.

Where can I find Gcc calling conventions for PSP MIPS? And how can I know the offset of each struct element? Because gcc optimizations can pack or align data as the compiler wants.

Thanks again!

[sauron_le_noir]

Have you try to compile with gcc optimization set to -G0 no optimization ?

[davidgf]

Already done, but dead code removal seems to apply even with no optimization.
Another think that GCC does is:

[crazyc]

How about this;

[davidgf]

I'll try the noreorder later, but I don't know for sure if I need to place nops after comparisions.
I don't get at all what push and pop statements do, but anyway I'll give a try.

The label problem I solved this way. My code has a lot of C comparisions with early out:

if (dist> radius) return 0;

I the last jump I changed the C code to this

if (bla bal ) {
exit_label: return 0;
} else {
bla bla
return 1;
}

so I can do
bvt 0, exit_label

There's no way the code exits function without returning anything, but this way gcc does'nt remove anything from my code and I can jump.

I'll post the conclusions so it might help someone.

Thanks for all!

David