This makes codegen faster (by perhaps 10-20% in the case of Jit64,
I didn't measure too closely), which helps speed up NBA Live 2005
a little. But the game still has serious performance issues.
These tends to get requested from either pure GDB or Ghidra. They reduce the verbosity of the communications. The QSupported packet is also important to implemnent for future proofing too.
The stub was made with the assumption that the GDB architecture is rs6000:6000, but the closest is actually powerpc:750 which features much more SPR that the gekko supports, but it also has slightly different ID. This commit now assumes the more proper powerpc:750.
It's always a good sign when the comments say "this will definitely
crash" and "I don't know if this is for a good reason".
Fixes https://bugs.dolphin-emu.org/issues/12762.
This piece of code is rather hard to understand, but my best guess
at what it's trying to do is that it tries to create opportunities
to skip writing CRs back to ppcState if we know that there are no
CR instructions (or branch instructions, etc) between an instruction
that writes to a CR register and the next blr. This is technically
inaccurate emulation, but as long as games don't do anything too
weird with their ABIs, I suppose it doesn't break anything.
So why do I want to get rid of it? Well, other than breaking some
hypothetical weird game, I imagine it could trip up people trying
to debug a game who are looking at the CR contents. And the code
is just plain confusing. (blr clearly doesn't write to CRs!)
It became irrelevant in 952dfcd610, when the define was removed; now, the code the comment is referring to is in JitRegister.cpp, and oprofile is controlled by cmake.
My change in 867cd99 caused farcode to fill up much more than before.
Most games still ran fine, but certain games would have multiple
cache clears per minute, on top of being overall slow.
Maybe there's something prettier we can do about this than just
allocating more RAM, but we have the resource budget for making
Dolphin use more RAM, so I consider increasing the size of the
cache to be a good solution at least for the time being.
At least for Prince of Persia: The Forgotten Sands, 48 MB isn't
enough to stop the cache clears, but 64 MB is. (I only played the
game for a few minutes when testing, though.)