With FP16_OVFL=1 the hardware writes an f16 result that would round to
infinity as the largest finite value of that sign, unless a source
operand is infinite. v_div_fixup_f16 keeps the infinity it writes for a
zero denominator or an infinite numerator. Measured on RDNA2 (gfx1036)
at IEEE=0 and IEEE=1 with f16 denormals kept and flushed.
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
The f16 min/max/min3/max3/med3 now pick NaN results on the bits and
quiet a signaling NaN only with IEEE=1. With IEEE=0, v_min_f64 and
v_max_f64 return the other operand for a NaN, not a quieted NaN. This
completes #1826 for these forms, as measured on RDNA2 (gfx1036).
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
With IEEE_MODE=1 the hardware quiets a signaling NaN that v_cubesc,
v_cubetc or v_cubema_f32 returns, keeping the sign the instruction gives
it; with IEEE=0 the bits pass through. Same rule as #1867, measured on
gfx1036 in both modes.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
A draw that rasterizes both faces with different front and back depth
bias was rejected, since Vulkan has one depth bias per draw and the
cull mode is pipeline state. Such a draw is now recorded twice in the
same pass: front faces with the back faces culled and the front bias,
then back faces with the front faces culled and the back bias. A face
whose offset is disabled gets no bias.
With f32 denormals flushed, as in the 0xc0 float mode titles use, the
hardware flushes all three v_mullit_f32 sources and its product like
v_mul_f32, so a positive denormal limit selects -FLT_MAX and a tiny
product gives zero. The recompiler kept denormals in every mode.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
With IEEE_MODE=1 the hardware quiets each signaling NaN half that
v_pack_b32_f16 packs, after neg and abs; with IEEE=0 it copies the bits.
The recompiler always copied them. Same rule as #1867, measured on
gfx1036 in both modes.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
A title that opens a main and an overlay port flips both, and every flip
was presented as a whole frame, so the window alternated between the two
buses: PPSA01736 shows its intro on the main bus and an empty overlay,
and the intro blinked black on every other frame. Overlay flips now
complete and signal their events without being shown. Compositing the
overlay over the main output is not implemented.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Vulkan counts the framebuffer colour attachments against maxPerStageResources
for the fragment stage. The draw's attachment count now seeds the fragment
stage's resource total in ShaderResources, so a pixel shader whose buffers and
images fit the limit but whose pipeline exceeds it throws instead of creating
an invalid pipeline. The draw resource cache key carries the attachment count,
so a cached build is never reused by a draw with more attachments.
The f16 forms of v_fma_mix computed an f32 FMA and converted it to f16,
so a result that lands on an f16 tie after the f32 rounding was rounded
twice. RDNA2 rounds the exact product-sum once. They now use the exact
f64 path of v_interp_p2_f16 and flush f32 sources like v_fma_mix_f32.
They follow the f16 round and denormal fields on hardware, so another
f16 mode throws, as packed f16 does.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
DEPTH_CLEAR_ENABLE (DB_RENDER_CONTROL bit 0, Mesa sid.h) makes the DB
write DB_DEPTH_CLEAR wherever the draw covers. Such a draw is now
rasterized as submitted with an always-passing depth write, no depth
bounds, no depth bias and the viewport depth range pinned to the clear
value, so it touches exactly the pixels the title's geometry covers.
Clearing a read-only or absent depth plane throws, at decode and in the
draw precheck. Depth and stencil clears combine; copy, resummarize and
decompress draws still throw.
Uncharted: Legacy of Thieves Collection (PPSA05684) clears with draws
that set DB_RENDER_CONTROL to 0x3 and stopped with "depth/stencil
clear, copy, resummarize or decompress draws (DB_RENDER_CONTROL) is
unsupported (register 0x0 = 0x00000003)".
VOP3 0x140 is v_mad_legacy_f32 on gfx10.1. Measured on gfx1010 (RX 5700
XT) in wave32 and wave64, IEEE 0 and 1 and f32 denormal modes 0 to 3, it
rounds the product before the add, flushes f32 denormal sources, product
and result in every mode, and gives a +0 product for a zero factor.
The translation multiplies, applies the zero rule and flushTinyProduct,
adds, and keeps the nanResultF32 wrapper. f32DenormalFlushFor returns 3
for the instruction before reading FLOAT_MODE. A sum of two zeros takes
its sign on the bits, as lavapipe returned -0 for +0 + -0. The execution
test pins the measured results and compares NaN bits exactly. RDNA2
(gfx1031), where the encoding is v_fma_legacy_f32 and fused, is noted in
TechnicalDebt.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>