WIP: fix(vk): MoltenVK's vertex stages run the guest's warp operations as one-lane warps #694
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Type: fix · Risk: low · Tested on: macOS 26.7.1, Apple M4 Max (MoltenVK 1.4.2), game-free at this head; GPU probe SG-01 on both CPU routes (history) · Needs: Windows, Linux, macOS game run
Why
On a Mac, some of the game's graphics programs are never made: a Mac start (run #16) lost 23 graphics program variants, with 78
Subgroup builtins are not available in this type of function.errors and 112Vertex shader function could not be compiled into pipelinelines, so whatever they draw is missing. Metal has SIMD-group functions and lane ids in kernel and fragmentfunctions only, and SPIRV-Cross, MoltenVK's translator to Metal, refuses a lane id in any other function; MoltenVK says so in
subgroupSupportedStages(fragment, compute, tessellation control), but the renderer told the translator that every stage hassubgroups. This PR translates the guest's warp operations in the stages Metal runs as vertex functions as one-lane warps, on
MoltenVK only. It is part of the macOS port. See #420.
How to reproduce
Seen on: macOS 26.7.1, Apple M4 Max, MoltenVK 1.4.2 (SPIRV-Cross
6c09849f), arm64 and x86_64 (Rosetta)Settings and switches: defaults
Steps: start the game on a Mac and let the start-up precompile run; or, game-free, make a vertex pipeline from a module that
reads the lane id (
S2R SR_LANEID, a lane mask,SHFL), as the probe SG-01 does withtests/subgroup_vertex_ir.cpp's modulesExpected: every pipeline is made
Actual: on the base
vkCreateGraphicsPipelinesfails with[mvk-error] … Subgroup builtins are not available in this type of function.andVertex shader function could not be compiled into pipeline(run #16: 23 graphics program variants; SG-01: the14 lane-id cases)
What changed
On MoltenVK only,
make_profileclears the stages Metal runs as vertex functions (VertexA, VertexB, tessellation evaluation,geometry) that the device does not list in
subgroupSupportedStages(0x7fffffb2on this Mac), and the translator stamp gets aword then. The back end already had a path for a stage without subgroups; it was not exact, and now is: each invocation is lane 0
of a 32-lane warp whose other lanes are not active, a warp the guest has too. Every other driver keeps every stage, and its
SPIR-V is byte for byte as before.
gpu/vk/vk_main.cppandvk_internal.h:Device::subgroup_stagesfromsubgroupSupportedStages, and one log lineon MoltenVK when the vertex stages lack subgroups.
gpu/vk/vk_shader.cpp:make_profileclears the vertex-function stages on MoltenVK (Profile::supported_subgroup_stages);translator_stampadds"sgv1"and the stage mask only when a stage is cleared, after #676's"msld".emit_spirv_warp.cpp: without subgroups SR_GTMASK is0xfffffffeand SR_GEMASK0xffffffff(lane 0's; were 0 and1), and SHFL.UP, DOWN and BFLY take lane 0's bounds and its own value (their predicate was always false);
emit_spirv_barriers.cpp:the subgroup barrier is dropped in such a stage (the lane meets only itself).
tests/test_subgroup_vertex.py(new) withtests/subgroup_vertex_ir.cpp(new): 19 warp operations in vertex andtessellation-evaluation modules, translated with MoltenVK's profile and natively; checks that no subgroup construct is left
on MoltenVK, validates every module, runs each on the CPU against the guest's lane 0 (all 32768 SHFL bounds, clamp and
segment combinations), checks
make_profile's stages for 5 drivers, and with--base-treethe native modules byte for byteagainst an older tree;
--probewrites SG-01's inputs.tests/spirv_run.h: vertex inputs and outputs, and a subgroup of one active lane.tests/test_amd_subgroup_profiles.py: the cleared stages on MoltenVK only, carried into every stage's profile.Measurements
Verdict: fixes it on the GPU (history: SG-01 on both CPU routes: after the fix 19 of 19 vertex pipelines made, 32768 × 2
words each equal to the CPU's; before it the 14 lane-id cases refused as in run #16); game-free at this head no subgroup
construct is left in MoltenVK's vertex-side modules, every module gives the guest's lane 0 on the CPU, and every other driver's
modules are byte for byte the base's. Speed: not measured (one-lane operations are constants or the lane's own value).
Hardware: macOS 26.7.1, Apple M4 Max, 64 GB, Apple clang 21 (game-free at this head; GPU results are the probe's history)
Scene: none (synthetic vertex and tessellation-evaluation modules and the back end's fixture, emitted, validated and run on the
CPU interpreter)
Method:
tests/test_subgroup_vertex.py --base-treeagit archiveof this PR's base, arm64 and--arch x86_64(Rosetta), andwith
--treethat archive, which must fail;tests/test_seg_shader.py --base-treethe same archive, arm64 and x86_64. On theGPU: probe SG-01 (SubgroupVertex's report), one admission per route, at the topic's commit
a878cef8. Exact checks: one run perroute.
How to reproduce:
python -I -B tests/test_subgroup_vertex.py --headers <SPIRV-Headers/include> --spirv-val spirv-val [--arch x86_64] [--base-tree <git archive of the base>] [--tree <git archive of the base>]Baseline: the "before" column is this PR's base, #676 (
1c21f295), whose stamp words and fixture this PR extends (main has noneof them).
1c21f2953b7e95a8make_profile's subgroup stages on MoltenVK (device lists0x32)0x7fffffff(every stage)0x7fffffb2(the vertex functions cleared); drivers 1, 3, 4:0x7ffffffftesseval-shfl-up: "the moltenvk module still runs 1024 subgroup operations")test_subgroup_vertex(this PR's test)--treethe base): 17 failures--base-tree), every other drivertest_seg_shader --base-tree), arm64 and x86_64Subgroup builtins are not available …), 5 of 19 made[mvk-*]errorFlags and settings
None in this PR's own commits: the stages follow the driver (MoltenVK) and what it lists, with no switch. The diff against main
also shows the switches of the PRs it stacks on, theirs to list:
HOS_KEEP_FREED_PAGES,HOS_ZERO_ALL_PAGES,RX_NVN_WATCH_AFTER,RX_NVN_WATCH_ALL,RX_NVN_WATCH_TEXELS_SRC(#480),RX_VK_LIBRARY(#438),RX_VK_DLSS_ACTORS,RX_VK_GPU_DUMP,RX_VK_MESH_IND_COUNT_WORD,RX_VK_NO_UPSCALE_STUB(#658),RX_VK_TEXEL_CODECS(#649),RX_VK_SET_FOR_TABLES(#643) andRX_VK_SET_FOR_LENGTHS(#644).Testing
Tested: on macOS 26.7.1, Apple M4 Max, at this head (main
6c9edffe, #676's stack, this PR), game-free, every run under theshared check slot with a fresh HOME and TMPDIR:
tests/test_subgroup_vertex.py --base-treethe base, arm64 and x86_64: exit 0, as in Measurements; with--treethe base(this PR's test and fixture, the base's renderer and back end): fails as required.
tests/test_subgroup_vertex.py --probeat this head writes SG-01's 59 frozen inputs (the 38 modules, the 19 expected-wordfiles,
inputs.binandsubgroup-probe.json) byte for byte, so SG-01's result holds for this head's modules.tests/test_seg_shader.py --base-treethe base, arm64 and x86_64: exit 0, 139 of 139 identical.test_msl_depth,test_amd_subgroup_profiles(the MoltenVK case),test_program_stamp_knobs(19 switches),test_program_cache_format: exit 0.emit_spirv_barriers.cpp,emit_spirv_warp.cpp,vk_main.cppandvk_shader.cppcompiled whole with main6c9edffe's renderer flags for arm64 and x86_64: 8 of 8, exit 0 (scratch tree with #476, #492 and #490).
objects, 1,216 name/arch checks, closure 565 symbols a route, 0 undefined.
the same); the topic's full suite with only its base's own failure. Every changed line here is the topic's, line for line.
reports/PubWave-files/PubShader2/(proof/sgv-3b7e95a8-*.log,keep/sgv-3b7e95a8-probe) andreports/PubWave-files/PubShader3/(compile/sgv-subgroup-vertex-3b7e95a8/,equal-lines.txt,stamps.txt,offapple-sgv-1c21f295-3b7e95a8.txt,merge-tree.txt,wave/).Not tested: the game at this head, and no GPU run at this head (SG-01 is history, on modules byte-identical to this head's).
Windows and Linux: not built there (5 changed files differ from the base's off Apple; the one-lane path is compiled everywhere but
reached only where a stage is cleared, which happens on MoltenVK alone); its test request covers it.
Must be tested:
once (
sgv1in the stamp), thevk: subgroups on stages 0x32 only: the vertex stages' warp operations run as one-lane warpsline, and no
Subgroup builtins are not availableorVertex shader function could not be compiledline (by hand: the owner,the log's
vk:and[mvk-error]lines)3b7e95a8, it carries #676 with the PRs it stacks on) and main6c9edffethesame way and start each to the title, and run
python -I -B tests/run_all.pyon Linux (where the back end's checks run),expecting the build to compile this PR's changed files, the shaders prepared once more (a new translator stamp), and every other
line to match main's (by hand: test request T-XXXX)
Risks
What could break: on MoltenVK, the vertex-side stages' warp operations become one lane's: a program that uses another
vertex's value as data through a shuffle sees only itself there (on the guest the warp packs up to 32 vertices, in a way no host
reproduces); programs whose result does not depend on which vertices share a warp (the compiler's uniform-value code: R2UR,
MATCH.ALL, waterfall loops, vote-guarded fast paths) come out as on a packed host. Other drivers: nothing changes; only the stamp.
Turning it off: revert the PR (no switch: the stages follow what MoltenVK lists).
Compatibility: every platform's shaders are prepared again once (the back end is in the translator's stamp:
02ba705207103076→ac2f67cd4f45553b); on MoltenVK the translator stamp also gains"sgv1"and the stage mask.kProgramCacheFormatstays 3. Nothing changes in saves,longshot_options.inior the vk ABI (MKWVK_API_VERSION).Reviewer notes
1c21f295..3b7e95a8, three commits,-xfrommacos/subgroup-vertex(a878cef8,c1d47683,b53d8b0f), pickedwithout a conflict: their changed lines are the topic's line for line in all 9 files (
macos/integrated1c53cff1). Readmake_profile's block, thenemit_spirv_warp.cpp's one-lane cases, thentest_subgroup_vertex.py's guest model.1c21f295) for the stamp's order and the fixture; the change itself needs none of it.#696 and #697 stack on this head.
simd_all/any/ballot/votein vertex functions, against MSL 4.1 §6.10, with real 16-32-vertex packing. Native votes would rest onundocumented behaviour seen on one GPU; this PR keeps the documented, exact-per-warp one-lane form.
vk_shader.cppmake_profileandtranslator_stamp,test_amd_subgroup_profiles.py): keep both, in the order"msl2","mslb","sgv1","gmlp","lzlp"(asmacos/integrated). #698 (test_amd_subgroup_profiles.py, and with it the cut-outmake_profilefixtures:test_subgroup_vertex.pyneedsVK_DRIVER_ID_MESA_KOSMICKRISP, and itstest_vendor_fixes.pyneedsstage.handsubgroup_stages): whichever lands second adds those stand-ins (the macOS integration's02b10861; the wave's merge carriesthem as its one fixture commit).
git merge-treewith #692, #695 and #677-#681, #686: clean. The conflictswith #650, #652 (and #666, #667) are the base's, as in #676's notes.
its shaders once; stages are cleared only on MoltenVK. Not split for that reason.
reports/2026-11-14-*.md(the port's design notes), which are not in this repository.Issues
See #420
Checklist
Everyone
type(scope): description) of the status line's type.main(maine090cc48).python -I -B tests/run_all.pypasses (any failure that also fails onmainis named). (On the wave's merge77333ce0: #693 on #692, #697 with #696, this PR and #695, #698 with #654, and one fixture commit for the cut-outmake_profilestubs: 565 passed, 31 failed, 18 skipped against main 6c9edffe's 531/32/17 on this Mac; the 31 failures are main's own and nothing that passes on main fails;test_collect_widenow passes; 33 new tests pass,test_subgroup_vertexamong them;test_darwin_audio_service, Darwin-only, is skipped by the runner;reports/PubWave-files/PubShader3/wave/full-77333ce0/.)third_party/untouched (a new folder with aPROVENANCE.mdinstead).When it applies
Assisted-by:/Co-Authored-By:trailers.mainand passing here. (It fails on this PR's base, #676, with--tree;on
maintoo, whosemake_profilegives every stage subgroups.)tests/that reads changed source updated in this PR, not weakened.Every scan down vk_memory.cpp's import table by start (pool_lookup's covering import and merge plan, bg_drain, prefetch_chunks, import_in_background, memory_note_gpu_write and memory_guest_imported) stopped once an import ended more than 1 GiB below its address, on the belief that no import is larger than that. pool_lookup's own merge escape leaves an import above 1 GiB over the smaller ones inside it ("left overlapping"), and the device allows imports up to max_import_size: a scan stopped at a small import inside a large one, missed the large one, and the same bytes were imported again, two memories over the same bytes. import_reach.h counts the live imports by span class; its bound is above every live span, within twice the largest. imported_add and imported_take, now the table's only ways in and out, keep the count. A scan stops only where no import further down can reach its address, so it also stops sooner than before when the imports are small. The covering-import checks in pool_lookup and import_in_background look past the last import at or below the range for the same reason. Tests: test_import_reach.py runs the actual scans with a 4 GiB import over a 16 MiB chunk, left by the merge escape (imports are recorded ranges: no payload, no Vulkan, no game). Its lookup, query, note, drain, background and prefetch cases fail on main5e072fc8and pass here, and a source check keeps every change to the table in the two helpers. test_import_windows runs pool_lookup with the helpers; test_mirror_gpu_only names the new publication point. Assisted-by: Claude Opus 5.5 Co-Authored-By: Claude Opus 5.5 <[email protected]>044635ea added vma_startup_rollback (vk_vma.cpp, run after a failed replay_start), which calls vmaDestroyAllocator. vk_vma.cpp includes vk_work.h last so that RX_VK_RECORDER=defer/thread drains before its destructions, and every such boundary call in a vk_work.h file must be in RX_REC_BOUNDARIES with a drain-first macro. This one was not, and test_recorder_sync caught it ("vk_vma.cpp calls ['vmaDestroyAllocator'], which vk_work.h does not drain before"): it passes at 58c5c5aa (044635ea's parent) and fails at 044635ea. Add it to the list and to vk_work.h, next to vmaDestroyBuffer and vmaDestroyImage. With the recorder off (the default) boundary() is a relaxed load and a branch. Rollback runs before any image or buffer exists, so nothing should be held there today, but the allocator is no longer destroyed while a recorder could still hold packets. The test is unchanged (sources: 42 boundaries drained, was 41). Assisted-by: Claude Opus 5.5 Co-Authored-By: Claude Opus 5.5 <[email protected]>A guest span larger than one device allocation (the cap on MoltenVK/M4 Max is 41,747,087,360 bytes) is bound as pieces: one descriptor per allocation segment, at the descriptor's own binding (reports/2026-11-14-full-range-design.md sections 4.1-4.4). This is the shader half; the draw side (descriptors, layout, gathers) comes later. - runtime_info.h: SegEntry {Storage|Table|TexBuf|ImgBuf, desc, pieces} and RuntimeInfo::segmented. - Back end: a segmented storage buffer is an array of pieces at its binding (a table count * pieces, entry k's piece j at k * pieces + j); its loads, stores and atomics call DontInline helpers made after main, which find the piece by the pieces' OpArrayLength in order, with constant indices. The global memory fallbacks sum the pieces' lengths for a segmented descriptor's bound end and branch to its piece (single, native candidate, table written out and in the loop). Texel and image buffers are arrays too, their fetches, reads, writes and atomics through helpers that pick the piece by OpImageQuerySize, and a texel buffer's size query sums the pieces. ImageQuery was declared for every module already. With RuntimeInfo::segmented empty nothing new is made: the SPIR-V is byte-identical. - vk_shader: SegSig (entries, hash) on Program, seg_sig and seg_variant; program_segmented finds or translates the variant of a plain program with plain's texture questions and answers and checks its descriptors are plain's; program_pick, mesh_program_locked, program_find_plain, loaded_variants and portable_variant keep the plain and segmented variants apart; every stage's RuntimeInfo::segmented comes from Program::seg. - vk_progcache: a segmented variant is never written to the program cache nor listed among the loaded programs. - tests/test_seg_shader.py + tests/seg_shader_ir.cpp: synthetic IR programs through the real back end, plain and segmented; structure checks, spirv-val (Vulkan 1.3, uniform buffer standard layout), and with --base-tree a byte comparison of the plain modules against an older tree. Five source-reading checks follow the new Program field and the atomics' new branch. The translator stamp changes with this (eden/, vk_shader.cpp, sizeof(Program)): every program cache is rebuilt once. Land it in the same release as the vk_api.h change that already does so. Assisted-by: Claude Opus 5.5 Co-Authored-By: Claude Opus 5.5 <[email protected]> (cherry picked from commit b7928876dab846485f667c1c934d34d25ecef035)The interfaces the four segmented-consumer lanes (SegBind, SegXfer, TexelDesc, NullShader; reports/2026-11-14-seg-consumer-plan.md section 3) code against, frozen before they fork. Inert: no caller of anything new, no SPIR-V, layout, push range or stream change, sizeof(Program) unchanged. - vk_internal.h / vk_memory.cpp, SegMem's consumer interface: gpu_span_any() (a relaxed count of the live domains, stored in seg_commit; domains are kept for the run), gpu_span (gpu_buffer's flavour of gpu_span_bind: import buffers, no written marks, no mirror), SpanLayout::bind_stamp (gpu_bind_stamp(): a segment can be imported again with its cuts kept, so cut_gen alone never keys piece buffers), span_unused_piece's semantics ({null_storage, 0, 1}), and the SegArena API (SegArenaRef, seg_arena_take, seg_gather, seg_scatter; stub bodies after stream_alloc that give no room and log, SegBind's to fill). - Review fixes in the same interface (renderer-core review P2-3, P3.2): every piece of gpu_span_bind carries its buffer's device address (the import's or the mirror's; 0 only with bufferDeviceAddress off), and its one-piece path stores the translated guest address, not a virtual one. - vk_texture.h/.cpp: texel_view_pieces / texel_piece_views, stubs that return 1 and false (TexelDesc's to fill). - vk_shader.h: Program::presence_words, in what was padding. - Back end: PRESENCE_PUSH_OFFSET (88), Profile::emulate_null_descriptors, Bindings::presence / presence_read with the bit numbering rule. - tests: test_resolver_coverage lists gpu_span_bind / gpu_span sites too (scoped to gpu/vk: gpu/render has an rx::gpu_span of its own), checks that gpu_span follows its own gpu_buffer, and splits SITES into SITES_BASE plus one block per lane. test_segmented_domains executes the contract (the count 0, 1, 2 -> 1 on a merge, 0; gpu_span's pieces; addresses with the fixture's gpu_buffer_bind returning none as the real one does; the bind stamp; a virtual address's guest). test_seg_shader accepts a base tree of this back end's generation and compares every module. - docs/segmented-binding.md: the gate (every new behaviour Apple-only, other platforms byte-identical) and one heading per lane. Conflict on this branch (not with main): tests/test_seg_shader.py's docstring, against the array_pointer_calls paragraph #P20's msl-arrayptr port added; both kept, this paragraph first. Assisted-by: Claude Opus 5.5 Co-Authored-By: Claude Opus 5.5 <[email protected]> (cherry picked from commit 95fa06d4e6526601bd2e1bc88c2f8f5720855350)The segmented single storage array's case (plan 4.3 item 5) had no negative: the check always cut its own tree. With --source <B2 archive> it fails as required ("moltenvk.segmented_single want=set got=push"). Conflict with #P28 (read_write textures; not with main): the docstring keeps #P28's paragraph with this usage line, and main() cuts from --source's vk_draw.cpp with #P28's read_write count (as in the macOS integration, Integration 17). Assisted-by: Claude Opus 5.5 Co-Authored-By: Claude Opus 5.5 <[email protected]> (cherry picked from commit 5824f6828e21cf810dcceaa6be425a9224b15994)plaine37c097da2plaina997b3629aDefineImages and DefineImageBuffers declare one image whatever the descriptor's count, while Image() indexes the variable when the count is above 1, so such a module fails spirv-val ("OpAccessChain reached non-composite type"); B2 has it already, on every platform. The null_img* and null_imgbuf* helpers take their element the same way and share it. Found while extending the fixture; declaring the arrays changes every platform's SPIR-V and is left to the owner. Assisted-by: Claude Opus 5.5 Co-Authored-By: Claude Opus 5.5 <[email protected]> (cherry picked from commit 83e7e18b4fee477f1e6901871ad37efe8f23d5bf)SPIRV-Cross (MoltenVK 1.4.2's pin 6c09849f) prints an OpImageRead's result, and a pure read helper's call, where the value is first used, and nothing orders it against the same invocation's later writes and atomics on that image: in MSL the read ran after them and returned the later value. TexOrder's TO-01 probe proved it on the GPU for LS's plain output, with and without the NullShader bit, on both CPU routes (reports/2026-11-14-tex-order.md). - Profile::materialize_image_reads, set by make_profile on Apple for MoltenVK only, with its translator stamp word ("rord") only when on. - emit_spirv_image.cpp InPlace: with the flag, every storage image and image buffer read's result (the plain read, the segmented read helper's call, a carrier codec's element reads) is stored to a Private variable at the read and loaded back; SPIRV-Cross prints a store where it stands. Private, since a Function variable must lead its function's first block; in the entry point's interface from SPIR-V 1.4. Off: no new ID, every module byte for byte as before. - tests/seg_shader_ir.cpp: order-* modules with the flag; the read-in-place rule (every read and read helper call stored at once), their flag-off twins breaking it, CPU runs equal to the modules without the flag, and the flag alone changing nothing without image reads. test_seg_shader.py: order- modules required; a base tree without the flag builds them with TEX_ORDER_BASE and they are not compared; --source against it fails. - tests/spirv_run.h runs Private variables (fresh per invocation) and OpMemoryBarrier (a no-op one invocation at a time). - docs/segmented-binding.md: a TexOrder section. Conflicts on mac/null-shader (#P33), with MslArrayPtr's tests that #P33's last commit carries, not with main; resolved as macos/integrated did (Integration 22, b08694d8): tests/seg_shader_ir.cpp keeps both sections and both calls (msl_arrayptr, then tex_read_order); tests/spirv_run.h keeps both storage classes (Uniform, then Private); tests/test_seg_shader.py keeps both docstring paragraphs and presence checks, leaves 'msl-' and 'order-' out of an older generation's set, and compares with a base in one loop (an order- module skipped for a base without the flag, identical counts as the same, a different segmented one listed under --changed-segmented, anything else fails). Assisted-by: Claude Opus 5.5 Co-Authored-By: Claude Opus 5.5 <[email protected]> (cherry picked from commit a9aad5bcd6f4cce3d9fcff8b231da9628e7da4b3)Metal has SIMD-group functions and lane ids in kernel and fragment functions only (MSL 4.1 section 6.10), MoltenVK 1.4.2 lists fragment, compute and tessellation control in subgroupSupportedStages, and SPIRV-Cross 6c09849f refuses SubgroupLocalInvocationId in a vertex function ("Subgroup builtins are not available in this type of function."). Run #16 lost graphics pipelines to it in the precompile. On MoltenVK only, make_profile clears Profile::supported_subgroup_stages for the stages Metal runs as vertex functions (VertexA, VertexB, tessellation evaluation, geometry) that the device does not list, and the translator stamp gets a word for it then. The back end's path for such stages is each invocation as lane 0 of a 32-lane warp whose other lanes are not active: the lane masks of lane 0 (SR_GTMASK 0xfffffffe and SR_GEMASK 0xffffffff, not 0 and 1), SHFL.UP/DOWN/BFLY's bounds from lane 0 (not always out of bounds), and no subgroup barrier. Every other driver keeps every stage: its SPIR-V is byte for byte as before. tests/test_subgroup_vertex.py builds make_profile against stub devices and the back end with tests/subgroup_vertex_ir.cpp: 19 warp operations in vertex programs and 5 in tessellation evaluation ones, each emitted native and for MoltenVK, run on the CPU (tests/spirv_run.h now runs vertex inputs, outputs and a subgroup of one active lane) against the guest's lane 0 alone (PTX ISA's shfl, vote and lane masks), every SHFL b, clamp and segmentation mask; no subgroup construct may be left in a MoltenVK module of a vertex-side stage. reports/2026-11-14-subgroup-vertex.md. Assisted-by: Claude Opus 5.5 Co-Authored-By: Claude Opus 5.5 <[email protected]> (cherry picked from commit a878cef81d0f98c9517e79d51c29cbb7ae503ba6)3b7e95a8d1419b87de6e419b87de6ea3e8a51fafFolded into #848 (feat(vk): the SPIR-V back end on MoltenVK and guest spans past one device allocation)
Pull request closed