[Joey-Magnus]

The last of OoT's programs that fail to translate (f24a3ebf686232fb, a compute program with matrix multiplies) is refused as "native program has no unconditional EXIT". It's a loop that leaves only through @P0 EXIT, so it has no unconditional EXIT. It ends the way NVIDIA's compiler closes such programs: the loop's unconditional BRA back, then a BRA to itself that nothing reaches.

The end of the program (instructions 1808-1809, then NOP padding to 1823; its five EXITs at 646, 956, 1244, 1525 and 1528 are all @P0):

1808  00007947 ffffb710 0383ffff 000fea00   BRA 642     (the loop, unconditional)
1809  00007947 fffffff0 0383ffff 000fc000   BRA 1809    (the closing self-branch)

Change (lower_to_maxwell.h, BRA): the closing self-branch already ended a program after a jump table (computed_branch). It now also ends one when the instruction before it is an unconditional BRA or EXIT, so nothing can fall into it, and the program makes no calls. finish still refuses if any branch points past the end. A self-branch that can be fallen into is still not an end, and programs that end at an unconditional EXIT end there as before.

Tests

• New tests/test_lower_end_at_closing_branch.py: @P0 EXIT; BRA 0; BRA self lowers and ends at the self-branch (refused on main). After a NOP, the self-branch is no end. @P0 EXIT; EXIT; BRA self ends at the EXIT as before.
• run_all.py: all pass except nx2/test_nup_stand_in.py, red on main (fixed by test(nup): the stand-in test's stub takes the progress #1764 passes (main is red) #1790).
• In game (Linux, RTX 4070 Ti, 595.99.02, tensor emulation on as by default), stacked on fix(shaders): lower TLD.MS (multisampled texel fetch) to Maxwell TLDS 2D.LZ.MS #1769/fix(shaders): LDG/STG [URn+imm] with ordering bit 78 lower (2 compute programs) #1778/fix(shaders): ISBERD.O, a task program reading back its payload (12 failing pipelines) #1789/fix(shaders): two large compute programs lower (an immediate is not R254) and get their local memory #1800/fix(shaders): R2UR's source is one register, not a pair (a vertex program refused) #1806: no program fails to lower any more (10 this morning). The startup build's failed programs are 22 → 1; the one left is a saved seed whose stage could not be rebuilt, not a translation failure.

🤖 Generated with Claude Code