DecodeState and the draw precheck rejected DB_SHADER_CONTROL bit 16,
PRIMITIVE_ORDERED_PIXEL_SHADER (POPS), which runs the ordered section
of overlapping pixels' shaders in primitive order. The bit now reaches
the recompiler as a pixel stage field, and such a pixel shader declares
PixelInterlockOrderedEXT and runs its whole body between
OpBeginInvocationInterlockEXT and OpEndInvocationInterlockEXT; an
invocation that a BDA read fault kills ends the interlock first. The
POPS collision SGPRs read 0, so a title skips its POPS wait and runs
its per-collision loop once. An image_load still reads a sampled
binding, which misses an earlier overlapping primitive's image_store in
the same draw. The device enables VK_EXT_fragment_shader_interlock when
it has fragmentShaderPixelInterlock; without it the recompile throws,
as does a nonzero POPS_OVERLAP_NUM_SAMPLES. The field is part of the
recompile cache key, the draw key and the serialized request (version 10).
A compute program with COMPUTE_PGM_RSRC2.SCRATCH_EN takes its per-lane private size from the AGC
shader header (scratch_size_dw_per_thread) instead of being refused. The size travels in
ShaderComputeStageInfo (cache key, request serialization version 10) to the translator, whose
scratch accesses already lower to a per-invocation Function array of that many dwords.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
NVIDIA 610.62 cannot sample R8G8_SRGB, and lavapipe can sample neither
it nor R8_SRGB, so an 8_8 sRGB T# made an image the device does not
support: creating it crashes the NVIDIA driver and lavapipe loads zeros.
The device's format support is read once. An 8 or 8_8 sRGB texture the
device cannot sample is created and viewed as R8_UNORM or R8G8_UNORM,
and SpirvTarget::srgbDecodeFormats makes the materializer mark the
image, so image loads map every channel through a 256-entry table of
the sRGB EOTF rounded to nearest even at bf16 precision, which is what
RDNA2 (gfx1035) returns; both channels of 8_8 are sRGB, and DST_SEL 0
and 1 map to themselves. Samples and gathers of such an image throw,
and its bindless table entries are unmapped like converted formats.
APS5_SRGB_SHADER_DECODE=1 takes this path on every device. Shader disk
cache entries and keys carry the mark: cache format version 7.
DecodeState, the draw precheck and DecodePixelStageInfo rejected every
nonzero CONSERVATIVE_Z_EXPORT (DB_SHADER_CONTROL bits 13-14).
EXPORT_LESS_THAN_Z (1) and EXPORT_GREATER_THAN_Z (2) promise that the
exported Z stays on one side of the interpolated Z. The value now
reaches the recompiler as a pixel stage field, and a pixel shader that
writes FragDepth declares DepthLess or DepthGreater next to
DepthReplacing, the SPIR-V modes RADV maps to these values. Vulkan lets
those modes only add a depth test of the interpolated Z before shading,
so a shader that keeps the promise renders the same. The reserved value
3 still throws.
The field is part of the recompile cache key, the draw key and the
serialized request (version 7), and ValidateShaders accepts both modes.
image_sample_*_o takes its texel offset from an address VGPR. The emitter
accepted only an immediate there and failed with "requires a constant texel
offset for image sampling" for any other, including an offset the program
moves into the VGPR under EXEC.
An offset that resolves to a constant at its packed address position stays a
ConstOffset. Any other becomes the Offset image operand, which Vulkan allows
on sampling instructions only with VK_KHR_maintenance8's maintenance8 feature
and the ImageGatherExtended capability. The device enables maintenance8 when
available and reports it through SpirvTarget::nonConstantImageOffsets, which
the cache key, the request serialization (version 6) and the SPIRV-Tools
validator options follow. Without it the sample still fails.
agc_shader_replay --maintenance8 recompiles a request for such a device.
SPI_PS_INPUT_ENA/ADDR with PERSP_CENTROID (bit 2) or LINEAR_CENTROID
(bit 6) was rejected; PPSA21564 binds 0x326 (perspective center and
centroid, linear center, POS_X/Y).
The PS input VGPR layout now follows the hardware rule: SPI_PS_INPUT_ADDR
places every input it names in SPI order (two VGPRs per I/J pair, three
for the pull model, one otherwise), loaded or not, and ENA & ADDR selects
the loaded ones. ShaderPixelStageInfo carries inputAddr (replacing
perspectiveCenterVgpr) plus perspectiveCentroid and linearCentroid; the
recompiler places each loaded input with PixelInputVgpr. This also fixes
the system inputs, which were always written from v0 (psSystemInputBase
was never set), so POS_X overwrote the center I in any draw with
barycentrics enabled.
Draws are rasterized single-sampled, where the centroid is the pixel
center: with fragment barycentrics the centroid pairs carry the center
barycentrics (BaryCoordKHR for perspective; the linear center and
centroid pairs now get BaryCoordNoPerspKHR).
NoPerspective was decided for every parameter by one flag (LINEAR_CENTER
loaded). v_interp_p2 now records whether it reads the J of a linear or a
perspective pair, and a parameter is NoPerspective when it is read
through a linear pair; parameters read through neither keep the old
rule. A parameter read through both kinds of pair throws. Only pixel
stages consult this.
The request serializer moves to version 5 (older requests read back with
their loaded inputs as the layout); the cache key and the driver's draw
key compare and hash the new fields. The unsupported-input error names
ENA and ADDR.
The geometry path's merged ES/GS programs (VGT_SHADER_STAGES_EN.GS_EN)
were compiled as mesh-stage programs whose input metadata was never
filled in, so every such draw failed with "mesh shader translation
configuration is not supported".
Recompiler:
- BuildShaderStageInputInfo takes the draw's MeshConfiguration; the mesh
input helpers (primitive size, step and counts) are implemented.
- The prologue emulates one NGG subgroup per workgroup: s2 GS_TG_INFO,
s3 the merged wave info per wave, the GS vertex offsets (ES thread
index times VGT_ESGS_RING_ITEMSIZE, odd strip triangles swapped), the
primitive id, and the ES vertex and instance ids. An indexed draw's
vertex id is read from the index buffer through a raw V# the driver
puts in hidden user words 4..7.
- s_sendmsg GS_ALLOC_REQ becomes MeshAllocate. The epilogue zeroes the
allocation first, clamps it to the output limits, culls primitives no
thread exported and decodes the 9-bit vertex indices.
- The draw parameters live in the last six push dwords. A BDA fault in
a mesh program no longer stops the invocation (as for other programs
with barriers, the fault is recorded and the read returns zero), so
every invocation reaches the subgroup barriers and the epilogue.
- The cache keys cover the mesh configuration; requests serialize its
new esgsItemSize field (version 4).
Driver:
- DecodeShaderStages reads VGT_ESGS_RING_ITEMSIZE (now in the draw key)
and sizes the subgroup for its ES vertices, GS primitives and outputs.
- Stages compile below the mesh draw parameters, which every mesh draw
pushes; the mesh stage always takes part in the push range.
- The index-buffer V# is set per draw (per record on the CPU-resolved
indirect path); the index-buffer alias check spares read-only
elements.
- The workgroup and LocalSize checks count two guest lanes per
invocation on 32-wide subgroups; mesh draws may carry a first vertex
or instance.
agc_driver_mesh_tests (EXCLUDE_FROM_ALL, needs VK_EXT_mesh_shader)
recompiles a hand-assembled merged ES/GS program in the PS5 compiler's
layout and draws indexed and non-indexed triangle lists in one- and
two-wave subgroups and a triangle strip across odd-starting subgroups,
reading the pixels back. agc_shader_replay prints a request's draw and
mesh configuration.
Only the lines this branch added lose their comments; the commits before
keep them, with the reasoning behind each change, for whoever digs into
that code later.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
A dispatch sized in threads (USE_THREAD_DIMENSIONS) launches a partial last
workgroup on RDNA2, but the host rounds it up to whole groups, so the extra
threads ran: past the end of a node list they read past it and wrote over
live records.
Such dispatches now compile a separate variant (ShaderComputeStageInfo::
partialThreads, keyed only on whether it is set) whose entry EXEC excludes
threads at or past the requested size. The size reaches the shader as three
shader data dwords after the memory offsets (StageInputKind::
DispatchThreadLimit), is mixed into the dispatch cache key and the result
memo hash, and serialized in recompile requests (version 3). Whole-group
dispatches keep their variant.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Celegans12