[GXemul-devel] GXemul 0.4 target PPC

[claude v. <vit...@wa...>]

Hi,

I implement Float instructions in PPC target with softfloat.

I m looking for an advice.

Each float instruction, need to test if FPU is enable. Thus I need the reel PC to launch fpu exception.
In ic->args, I can only give 3 parameters (Rd, Ra, Rb). I don't want to provide the word in args and to decode it in the instruction.

I try to use this code.

int low_pc = ((size_t)cpu->cd.DYNTRANS_ARCH.next_ic - 
       (size_t)cpu->cd.DYNTRANS_ARCH.cur_ic_page) 
       sizeof(struct DYNTRANS_IC);   
   cpu->pc &= ~((DYNTRANS_IC_ENTRIES_PER_PAGE-1) << 
       DYNTRANS_INSTR_ALIGNMENT_SHIFT);  
   cpu->pc += (low_pc << DYNTRANS_INSTR_ALIGNMENT_SHIFT);

I get the pc+4 where is the instruction. It seems fine.

But I see your implementation of mtmsr and I don't understand why you don't use the code, above, when the instruction is executed. I don't find argument...

Other question
If I want to give a fourth argument in ic (arch ## _instr_call), I need to reduce the number of translated instructions ? I don't test this modification because I don't see all impacts...

Best regards,
Claude