Re: [Qemu-devel] [PATCH v3 2/8] target/mips: Add all MXU opcodes

[Janeczek, Craig]

I will re-work each of the mxu_gen_<ins> functions to check for MXUEN and jump 
over the implementation of the instruction if not enabled.

I would like to clarify the structure of the switch statement before 
implementing it.

I was originally planning on checking if there was a MXU hit and MXUEN was set, 
in that case use the MXU instruction, else use the original switch. This will 
not work as MXUEN is in a TCGv and cant be used in an if statement at that 
level. That is why I plan on putting the MXUEN check in each of the 
mxu_gen_<ins> functions.

What should the re-worked switch statement look like which runs the 
mxu_gen_<ins> functions? 

-----Original Message-----
From: Aleksandar Markovic <address@hidden> 
Sent: Tuesday, August 28, 2018 12:51 PM
To: Janeczek, Craig <address@hidden>; address@hidden
Cc: address@hidden
Subject: Re: [PATCH v3 2/8] target/mips: Add all MXU opcodes

> I see that I can check the loongson instructions by checking for 
> INSN_LOONGSON2F. Using MXU if that is not set

One more thing to check is MXUEN bit of MXU control register. This should be 
done before handling any MXU instructions, except S32M2I/S32I2M.

> What should I check for the mult or misc instructions that were there first?

It should be is somewhere in LOONGSON docs.