eglantine-cirakg/NX2_GPU_THREAD_SPLIT.md, branch nx2Mirror of github.com/cira0100/Eglantine-public nx2, a fork of Djihads80/Eglantine.https://git.cirakg.xyz/eglantine-cirakg/atom?h=nx22026-10-30T00:49:48+00:00video_core: GPU thread split on by default for Switch 2 titles; cheaper front paths2026-10-30T00:49:48+00:00Takoroka137927095+Takoroka@users.noreply.github.com2026-10-29T15:55:07+00:00urn:sha1:15e953cafd5cb348833cb373d7ddd996b81307f7
Clean A/B in title 1 (3 rounds each): 1.46x the draws a second of one
thread, frames 17% shorter, no crashes, front register copies equal to
the back's in 57,089 checks. EDEN_NX2_SPLIT=0 runs everything on one
thread, =1 keeps macros on the back.
The front's per-write paths no longer check guarded statics
(GpuSplit::Get, Nx2Profile::Enabled, the skip-same switches) and the
ring's method writes are inline. Notes row 145.
nx2: notes 142-144 (GPU thread split, scheduler race, front register copies)2026-10-30T00:49:48+00:00Takoroka137927095+Takoroka@users.noreply.github.com2026-10-29T15:18:19+00:00urn:sha1:17c10c3690eab1ab461318f7e3e8850d490fb753video_core: compile Turing MME macro code to x86-642026-10-30T00:49:48+00:00Takoroka137927095+Takoroka@users.noreply.github.com2026-10-29T13:39:25+00:00urn:sha1:c0643a675b1382cfa7357626a63a623b56a72666
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.