video_core: compile Turing MME macro code to x86-64

Title 1 calls macros ~1.3 million times a second; most were replayed from the macro memo,
whose lookups missed the CPU caches inside the GPU thread (~8%), and the rest interpreted.
macro_turing_jit.h compiles all of the uploaded macro memory with Xbyak: each instruction a
block falling through to the next, branches and loops through a jump table, with the
interpreter's semantics (lanes reading operands before either writes, predication as two
variants, the END delay slot, loops, carry). Loop checks only where a loop can end, END
checks only after an END, the instruction limit counted on indirect jumps. Emits and register
reads call back into C++. It is recompiled when the macro code changes and used for 3D and
compute macros on x86-64; EDEN_NX2_MME_JIT=0 goes back to the memo and the interpreter.

Checked against the interpreter on 200,000 recorded calls (registers, data RAM, every
method write, FIFO use): identical. In the game: macro calls 148 ns instead of 174 (two
profiled runs each), no failures, 0 crashes in 3 runs. NX2_GPU_THREAD_SPLIT.md describes
the next step, splitting the GPU thread.

0 files changed, 0 insertions, 0 deletions