mirror of
https://gitlab.freedesktop.org/mesa/mesa.git
synced 2024-12-14 04:34:23 +08:00
7b0bda2e55
We never enable this feature, so let's rip it out completely. Acked-by: Roland Scheidegger <sroland@vmware.com> Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/12505>
3852 lines
94 KiB
ReStructuredText
3852 lines
94 KiB
ReStructuredText
TGSI
|
|
====
|
|
|
|
TGSI, Tungsten Graphics Shader Infrastructure, is an intermediate language
|
|
for describing shaders. Since Gallium is inherently shaderful, shaders are
|
|
an important part of the API. TGSI is the only intermediate representation
|
|
used by all drivers.
|
|
|
|
Basics
|
|
------
|
|
|
|
All TGSI instructions, known as *opcodes*, operate on arbitrary-precision
|
|
floating-point four-component vectors. An opcode may have up to one
|
|
destination register, known as *dst*, and between zero and three source
|
|
registers, called *src0* through *src2*, or simply *src* if there is only
|
|
one.
|
|
|
|
Some instructions, like :opcode:`I2F`, permit re-interpretation of vector
|
|
components as integers. Other instructions permit using registers as
|
|
two-component vectors with double precision; see :ref:`doubleopcodes`.
|
|
|
|
When an instruction has a scalar result, the result is usually copied into
|
|
each of the components of *dst*. When this happens, the result is said to be
|
|
*replicated* to *dst*. :opcode:`RCP` is one such instruction.
|
|
|
|
Source Modifiers
|
|
^^^^^^^^^^^^^^^^
|
|
|
|
TGSI supports 32-bit negate and absolute value modifiers on floating-point
|
|
inputs, and 32-bit integer negates on some drivers. The negate applies after
|
|
absolute value if both are present.
|
|
|
|
The type of an input can be found by ``tgsi_opcode_infer_src_type()``, and
|
|
TGSI_OPCODE_MOV and the second and third operands of TGSI_OPCODE_UCMP (which
|
|
return TGSI_TYPE_UNTYPED) are also considered floats for the purpose of source
|
|
modifiers.
|
|
|
|
|
|
Other Modifiers
|
|
^^^^^^^^^^^^^^^
|
|
|
|
The saturate modifier clamps 32-bit destination stores to [0.0, 1.0].
|
|
|
|
For arithmetic instruction having a precise modifier certain optimizations
|
|
which may alter the result are disallowed. Example: *add(mul(a,b),c)* can't be
|
|
optimized to TGSI_OPCODE_MAD, because some hardware only supports the fused
|
|
MAD instruction.
|
|
|
|
Instruction Set
|
|
---------------
|
|
|
|
Core ISA
|
|
^^^^^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
These opcodes are guaranteed to be available regardless of the driver being
|
|
used.
|
|
|
|
.. opcode:: ARL - Address Register Load
|
|
|
|
.. math::
|
|
|
|
dst.x = (int) \lfloor src.x\rfloor
|
|
|
|
dst.y = (int) \lfloor src.y\rfloor
|
|
|
|
dst.z = (int) \lfloor src.z\rfloor
|
|
|
|
dst.w = (int) \lfloor src.w\rfloor
|
|
|
|
|
|
.. opcode:: MOV - Move
|
|
|
|
.. math::
|
|
|
|
dst.x = src.x
|
|
|
|
dst.y = src.y
|
|
|
|
dst.z = src.z
|
|
|
|
dst.w = src.w
|
|
|
|
|
|
.. opcode:: LIT - Light Coefficients
|
|
|
|
.. math::
|
|
|
|
dst.x &= 1 \\
|
|
dst.y &= max(src.x, 0) \\
|
|
dst.z &= (src.x > 0) ? max(src.y, 0)^{clamp(src.w, -128, 128))} : 0 \\
|
|
dst.w &= 1
|
|
|
|
|
|
.. opcode:: RCP - Reciprocal
|
|
|
|
This instruction replicates its result.
|
|
|
|
.. math::
|
|
|
|
dst = \frac{1}{src.x}
|
|
|
|
|
|
.. opcode:: RSQ - Reciprocal Square Root
|
|
|
|
This instruction replicates its result. The results are undefined for src <= 0.
|
|
|
|
.. math::
|
|
|
|
dst = \frac{1}{\sqrt{src.x}}
|
|
|
|
|
|
.. opcode:: SQRT - Square Root
|
|
|
|
This instruction replicates its result. The results are undefined for src < 0.
|
|
|
|
.. math::
|
|
|
|
dst = {\sqrt{src.x}}
|
|
|
|
|
|
.. opcode:: EXP - Approximate Exponential Base 2
|
|
|
|
.. math::
|
|
|
|
dst.x &= 2^{\lfloor src.x\rfloor} \\
|
|
dst.y &= src.x - \lfloor src.x\rfloor \\
|
|
dst.z &= 2^{src.x} \\
|
|
dst.w &= 1
|
|
|
|
|
|
.. opcode:: LOG - Approximate Logarithm Base 2
|
|
|
|
.. math::
|
|
|
|
dst.x &= \lfloor\log_2{|src.x|}\rfloor \\
|
|
dst.y &= \frac{|src.x|}{2^{\lfloor\log_2{|src.x|}\rfloor}} \\
|
|
dst.z &= \log_2{|src.x|} \\
|
|
dst.w &= 1
|
|
|
|
|
|
.. opcode:: MUL - Multiply
|
|
|
|
.. math::
|
|
|
|
dst.x = src0.x \times src1.x
|
|
|
|
dst.y = src0.y \times src1.y
|
|
|
|
dst.z = src0.z \times src1.z
|
|
|
|
dst.w = src0.w \times src1.w
|
|
|
|
|
|
.. opcode:: ADD - Add
|
|
|
|
.. math::
|
|
|
|
dst.x = src0.x + src1.x
|
|
|
|
dst.y = src0.y + src1.y
|
|
|
|
dst.z = src0.z + src1.z
|
|
|
|
dst.w = src0.w + src1.w
|
|
|
|
|
|
.. opcode:: DP3 - 3-component Dot Product
|
|
|
|
This instruction replicates its result.
|
|
|
|
.. math::
|
|
|
|
dst = src0.x \times src1.x + src0.y \times src1.y + src0.z \times src1.z
|
|
|
|
|
|
.. opcode:: DP4 - 4-component Dot Product
|
|
|
|
This instruction replicates its result.
|
|
|
|
.. math::
|
|
|
|
dst = src0.x \times src1.x + src0.y \times src1.y + src0.z \times src1.z + src0.w \times src1.w
|
|
|
|
|
|
.. opcode:: DST - Distance Vector
|
|
|
|
.. math::
|
|
|
|
dst.x &= 1\\
|
|
dst.y &= src0.y \times src1.y\\
|
|
dst.z &= src0.z\\
|
|
dst.w &= src1.w
|
|
|
|
|
|
.. opcode:: MIN - Minimum
|
|
|
|
.. math::
|
|
|
|
dst.x = min(src0.x, src1.x)
|
|
|
|
dst.y = min(src0.y, src1.y)
|
|
|
|
dst.z = min(src0.z, src1.z)
|
|
|
|
dst.w = min(src0.w, src1.w)
|
|
|
|
|
|
.. opcode:: MAX - Maximum
|
|
|
|
.. math::
|
|
|
|
dst.x = max(src0.x, src1.x)
|
|
|
|
dst.y = max(src0.y, src1.y)
|
|
|
|
dst.z = max(src0.z, src1.z)
|
|
|
|
dst.w = max(src0.w, src1.w)
|
|
|
|
|
|
.. opcode:: SLT - Set On Less Than
|
|
|
|
.. math::
|
|
|
|
dst.x = (src0.x < src1.x) ? 1.0F : 0.0F
|
|
|
|
dst.y = (src0.y < src1.y) ? 1.0F : 0.0F
|
|
|
|
dst.z = (src0.z < src1.z) ? 1.0F : 0.0F
|
|
|
|
dst.w = (src0.w < src1.w) ? 1.0F : 0.0F
|
|
|
|
|
|
.. opcode:: SGE - Set On Greater Equal Than
|
|
|
|
.. math::
|
|
|
|
dst.x = (src0.x >= src1.x) ? 1.0F : 0.0F
|
|
|
|
dst.y = (src0.y >= src1.y) ? 1.0F : 0.0F
|
|
|
|
dst.z = (src0.z >= src1.z) ? 1.0F : 0.0F
|
|
|
|
dst.w = (src0.w >= src1.w) ? 1.0F : 0.0F
|
|
|
|
|
|
.. opcode:: MAD - Multiply And Add
|
|
|
|
Perform a * b + c. The implementation is free to decide whether there is an
|
|
intermediate rounding step or not.
|
|
|
|
.. math::
|
|
|
|
dst.x = src0.x \times src1.x + src2.x
|
|
|
|
dst.y = src0.y \times src1.y + src2.y
|
|
|
|
dst.z = src0.z \times src1.z + src2.z
|
|
|
|
dst.w = src0.w \times src1.w + src2.w
|
|
|
|
|
|
.. opcode:: LRP - Linear Interpolate
|
|
|
|
.. math::
|
|
|
|
dst.x = src0.x \times src1.x + (1 - src0.x) \times src2.x
|
|
|
|
dst.y = src0.y \times src1.y + (1 - src0.y) \times src2.y
|
|
|
|
dst.z = src0.z \times src1.z + (1 - src0.z) \times src2.z
|
|
|
|
dst.w = src0.w \times src1.w + (1 - src0.w) \times src2.w
|
|
|
|
|
|
.. opcode:: FMA - Fused Multiply-Add
|
|
|
|
Perform a * b + c with no intermediate rounding step.
|
|
|
|
.. math::
|
|
|
|
dst.x = src0.x \times src1.x + src2.x
|
|
|
|
dst.y = src0.y \times src1.y + src2.y
|
|
|
|
dst.z = src0.z \times src1.z + src2.z
|
|
|
|
dst.w = src0.w \times src1.w + src2.w
|
|
|
|
|
|
.. opcode:: FRC - Fraction
|
|
|
|
.. math::
|
|
|
|
dst.x = src.x - \lfloor src.x\rfloor
|
|
|
|
dst.y = src.y - \lfloor src.y\rfloor
|
|
|
|
dst.z = src.z - \lfloor src.z\rfloor
|
|
|
|
dst.w = src.w - \lfloor src.w\rfloor
|
|
|
|
|
|
.. opcode:: FLR - Floor
|
|
|
|
.. math::
|
|
|
|
dst.x = \lfloor src.x\rfloor
|
|
|
|
dst.y = \lfloor src.y\rfloor
|
|
|
|
dst.z = \lfloor src.z\rfloor
|
|
|
|
dst.w = \lfloor src.w\rfloor
|
|
|
|
|
|
.. opcode:: ROUND - Round
|
|
|
|
.. math::
|
|
|
|
dst.x = round(src.x)
|
|
|
|
dst.y = round(src.y)
|
|
|
|
dst.z = round(src.z)
|
|
|
|
dst.w = round(src.w)
|
|
|
|
|
|
.. opcode:: EX2 - Exponential Base 2
|
|
|
|
This instruction replicates its result.
|
|
|
|
.. math::
|
|
|
|
dst = 2^{src.x}
|
|
|
|
|
|
.. opcode:: LG2 - Logarithm Base 2
|
|
|
|
This instruction replicates its result.
|
|
|
|
.. math::
|
|
|
|
dst = \log_2{src.x}
|
|
|
|
|
|
.. opcode:: POW - Power
|
|
|
|
This instruction replicates its result.
|
|
|
|
.. math::
|
|
|
|
dst = src0.x^{src1.x}
|
|
|
|
|
|
.. opcode:: LDEXP - Multiply Number by Integral Power of 2
|
|
|
|
src1 is an integer.
|
|
|
|
.. math::
|
|
|
|
dst.x = src0.x * 2^{src1.x}
|
|
dst.y = src0.y * 2^{src1.y}
|
|
dst.z = src0.z * 2^{src1.z}
|
|
dst.w = src0.w * 2^{src1.w}
|
|
|
|
|
|
.. opcode:: COS - Cosine
|
|
|
|
This instruction replicates its result.
|
|
|
|
.. math::
|
|
|
|
dst = \cos{src.x}
|
|
|
|
|
|
.. opcode:: DDX, DDX_FINE - Derivative Relative To X
|
|
|
|
The fine variant is only used when ``PIPE_CAP_TGSI_FS_FINE_DERIVATIVE`` is
|
|
advertised. When it is, the fine version guarantees one derivative per row
|
|
while DDX is allowed to be the same for the entire 2x2 quad.
|
|
|
|
.. math::
|
|
|
|
dst.x = partialx(src.x)
|
|
|
|
dst.y = partialx(src.y)
|
|
|
|
dst.z = partialx(src.z)
|
|
|
|
dst.w = partialx(src.w)
|
|
|
|
|
|
.. opcode:: DDY, DDY_FINE - Derivative Relative To Y
|
|
|
|
The fine variant is only used when ``PIPE_CAP_TGSI_FS_FINE_DERIVATIVE`` is
|
|
advertised. When it is, the fine version guarantees one derivative per column
|
|
while DDY is allowed to be the same for the entire 2x2 quad.
|
|
|
|
.. math::
|
|
|
|
dst.x = partialy(src.x)
|
|
|
|
dst.y = partialy(src.y)
|
|
|
|
dst.z = partialy(src.z)
|
|
|
|
dst.w = partialy(src.w)
|
|
|
|
|
|
.. opcode:: PK2H - Pack Two 16-bit Floats
|
|
|
|
This instruction replicates its result.
|
|
|
|
.. math::
|
|
|
|
dst = f32\_to\_f16(src.x) | f32\_to\_f16(src.y) << 16
|
|
|
|
|
|
.. opcode:: PK2US - Pack Two Unsigned 16-bit Scalars
|
|
|
|
This instruction replicates its result.
|
|
|
|
.. math::
|
|
|
|
dst = f32\_to\_unorm16(src.x) | f32\_to\_unorm16(src.y) << 16
|
|
|
|
|
|
.. opcode:: PK4B - Pack Four Signed 8-bit Scalars
|
|
|
|
This instruction replicates its result.
|
|
|
|
.. math::
|
|
|
|
dst = f32\_to\_snorm8(src.x) |
|
|
(f32\_to\_snorm8(src.y) << 8) |
|
|
(f32\_to\_snorm8(src.z) << 16) |
|
|
(f32\_to\_snorm8(src.w) << 24)
|
|
|
|
|
|
.. opcode:: PK4UB - Pack Four Unsigned 8-bit Scalars
|
|
|
|
This instruction replicates its result.
|
|
|
|
.. math::
|
|
|
|
dst = f32\_to\_unorm8(src.x) |
|
|
(f32\_to\_unorm8(src.y) << 8) |
|
|
(f32\_to\_unorm8(src.z) << 16) |
|
|
(f32\_to\_unorm8(src.w) << 24)
|
|
|
|
|
|
.. opcode:: SEQ - Set On Equal
|
|
|
|
.. math::
|
|
|
|
dst.x = (src0.x == src1.x) ? 1.0F : 0.0F
|
|
|
|
dst.y = (src0.y == src1.y) ? 1.0F : 0.0F
|
|
|
|
dst.z = (src0.z == src1.z) ? 1.0F : 0.0F
|
|
|
|
dst.w = (src0.w == src1.w) ? 1.0F : 0.0F
|
|
|
|
|
|
.. opcode:: SGT - Set On Greater Than
|
|
|
|
.. math::
|
|
|
|
dst.x = (src0.x > src1.x) ? 1.0F : 0.0F
|
|
|
|
dst.y = (src0.y > src1.y) ? 1.0F : 0.0F
|
|
|
|
dst.z = (src0.z > src1.z) ? 1.0F : 0.0F
|
|
|
|
dst.w = (src0.w > src1.w) ? 1.0F : 0.0F
|
|
|
|
|
|
.. opcode:: SIN - Sine
|
|
|
|
This instruction replicates its result.
|
|
|
|
.. math::
|
|
|
|
dst = \sin{src.x}
|
|
|
|
|
|
.. opcode:: SLE - Set On Less Equal Than
|
|
|
|
.. math::
|
|
|
|
dst.x = (src0.x <= src1.x) ? 1.0F : 0.0F
|
|
|
|
dst.y = (src0.y <= src1.y) ? 1.0F : 0.0F
|
|
|
|
dst.z = (src0.z <= src1.z) ? 1.0F : 0.0F
|
|
|
|
dst.w = (src0.w <= src1.w) ? 1.0F : 0.0F
|
|
|
|
|
|
.. opcode:: SNE - Set On Not Equal
|
|
|
|
.. math::
|
|
|
|
dst.x = (src0.x != src1.x) ? 1.0F : 0.0F
|
|
|
|
dst.y = (src0.y != src1.y) ? 1.0F : 0.0F
|
|
|
|
dst.z = (src0.z != src1.z) ? 1.0F : 0.0F
|
|
|
|
dst.w = (src0.w != src1.w) ? 1.0F : 0.0F
|
|
|
|
|
|
.. opcode:: TEX - Texture Lookup
|
|
|
|
for array textures src0.y contains the slice for 1D,
|
|
and src0.z contain the slice for 2D.
|
|
|
|
for shadow textures with no arrays (and not cube map),
|
|
src0.z contains the reference value.
|
|
|
|
for shadow textures with arrays, src0.z contains
|
|
the reference value for 1D arrays, and src0.w contains
|
|
the reference value for 2D arrays and cube maps.
|
|
|
|
for cube map array shadow textures, the reference value
|
|
cannot be passed in src0.w, and TEX2 must be used instead.
|
|
|
|
.. math::
|
|
|
|
coord = src0
|
|
|
|
shadow_ref = src0.z or src0.w (optional)
|
|
|
|
unit = src1
|
|
|
|
dst = texture\_sample(unit, coord, shadow_ref)
|
|
|
|
|
|
.. opcode:: TEX2 - Texture Lookup (for shadow cube map arrays only)
|
|
|
|
this is the same as TEX, but uses another reg to encode the
|
|
reference value.
|
|
|
|
.. math::
|
|
|
|
coord = src0
|
|
|
|
shadow_ref = src1.x
|
|
|
|
unit = src2
|
|
|
|
dst = texture\_sample(unit, coord, shadow_ref)
|
|
|
|
|
|
|
|
|
|
.. opcode:: TXD - Texture Lookup with Derivatives
|
|
|
|
.. math::
|
|
|
|
coord = src0
|
|
|
|
ddx = src1
|
|
|
|
ddy = src2
|
|
|
|
unit = src3
|
|
|
|
dst = texture\_sample\_deriv(unit, coord, ddx, ddy)
|
|
|
|
|
|
.. opcode:: TXP - Projective Texture Lookup
|
|
|
|
.. math::
|
|
|
|
coord.x = src0.x / src0.w
|
|
|
|
coord.y = src0.y / src0.w
|
|
|
|
coord.z = src0.z / src0.w
|
|
|
|
coord.w = src0.w
|
|
|
|
unit = src1
|
|
|
|
dst = texture\_sample(unit, coord)
|
|
|
|
|
|
.. opcode:: UP2H - Unpack Two 16-Bit Floats
|
|
|
|
.. math::
|
|
|
|
dst.x = f16\_to\_f32(src0.x \& 0xffff)
|
|
|
|
dst.y = f16\_to\_f32(src0.x >> 16)
|
|
|
|
dst.z = f16\_to\_f32(src0.x \& 0xffff)
|
|
|
|
dst.w = f16\_to\_f32(src0.x >> 16)
|
|
|
|
.. note::
|
|
|
|
Considered for removal.
|
|
|
|
.. opcode:: UP2US - Unpack Two Unsigned 16-Bit Scalars
|
|
|
|
TBD
|
|
|
|
.. note::
|
|
|
|
Considered for removal.
|
|
|
|
.. opcode:: UP4B - Unpack Four Signed 8-Bit Values
|
|
|
|
TBD
|
|
|
|
.. note::
|
|
|
|
Considered for removal.
|
|
|
|
.. opcode:: UP4UB - Unpack Four Unsigned 8-Bit Scalars
|
|
|
|
TBD
|
|
|
|
.. note::
|
|
|
|
Considered for removal.
|
|
|
|
|
|
.. opcode:: ARR - Address Register Load With Round
|
|
|
|
.. math::
|
|
|
|
dst.x = (int) round(src.x)
|
|
|
|
dst.y = (int) round(src.y)
|
|
|
|
dst.z = (int) round(src.z)
|
|
|
|
dst.w = (int) round(src.w)
|
|
|
|
|
|
.. opcode:: SSG - Set Sign
|
|
|
|
.. math::
|
|
|
|
dst.x = (src.x > 0) ? 1 : (src.x < 0) ? -1 : 0
|
|
|
|
dst.y = (src.y > 0) ? 1 : (src.y < 0) ? -1 : 0
|
|
|
|
dst.z = (src.z > 0) ? 1 : (src.z < 0) ? -1 : 0
|
|
|
|
dst.w = (src.w > 0) ? 1 : (src.w < 0) ? -1 : 0
|
|
|
|
|
|
.. opcode:: CMP - Compare
|
|
|
|
.. math::
|
|
|
|
dst.x = (src0.x < 0) ? src1.x : src2.x
|
|
|
|
dst.y = (src0.y < 0) ? src1.y : src2.y
|
|
|
|
dst.z = (src0.z < 0) ? src1.z : src2.z
|
|
|
|
dst.w = (src0.w < 0) ? src1.w : src2.w
|
|
|
|
|
|
.. opcode:: KILL_IF - Conditional Discard
|
|
|
|
Conditional discard. Allowed in fragment shaders only.
|
|
|
|
.. math::
|
|
|
|
if (src.x < 0 || src.y < 0 || src.z < 0 || src.w < 0)
|
|
discard
|
|
endif
|
|
|
|
|
|
.. opcode:: KILL - Discard
|
|
|
|
Unconditional discard. Allowed in fragment shaders only.
|
|
|
|
|
|
.. opcode:: DEMOTE - Demote Invocation to a Helper
|
|
|
|
This demotes the current invocation to a helper, but continues
|
|
execution (while KILL may or may not terminate the
|
|
invocation). After this runs, all the usual helper invocation rules
|
|
apply about discarding buffer and render target writes. This is
|
|
useful for having accurate derivatives in the other invocations
|
|
which have not been demoted.
|
|
|
|
Allowed in fragment shaders only.
|
|
|
|
|
|
.. opcode:: READ_HELPER - Reads Invocation Helper Status
|
|
|
|
This is identical to ``TGSI_SEMANTIC_HELPER_INVOCATION``, except
|
|
this will read the current value, which might change as a result of
|
|
a ``DEMOTE`` instruction.
|
|
|
|
Allowed in fragment shaders only.
|
|
|
|
|
|
.. opcode:: TXB - Texture Lookup With Bias
|
|
|
|
for cube map array textures and shadow cube maps, the bias value
|
|
cannot be passed in src0.w, and TXB2 must be used instead.
|
|
|
|
if the target is a shadow texture, the reference value is always
|
|
in src.z (this prevents shadow 3d and shadow 2d arrays from
|
|
using this instruction, but this is not needed).
|
|
|
|
.. math::
|
|
|
|
coord.x = src0.x
|
|
|
|
coord.y = src0.y
|
|
|
|
coord.z = src0.z
|
|
|
|
coord.w = none
|
|
|
|
bias = src0.w
|
|
|
|
unit = src1
|
|
|
|
dst = texture\_sample(unit, coord, bias)
|
|
|
|
|
|
.. opcode:: TXB2 - Texture Lookup With Bias (some cube maps only)
|
|
|
|
this is the same as TXB, but uses another reg to encode the
|
|
LOD bias value for cube map arrays and shadow cube maps.
|
|
Presumably shadow 2d arrays and shadow 3d targets could use
|
|
this encoding too, but this is not legal.
|
|
|
|
if the target is a shadow cube map array, the reference value is in
|
|
src1.y.
|
|
|
|
.. math::
|
|
|
|
coord = src0
|
|
|
|
bias = src1.x
|
|
|
|
unit = src2
|
|
|
|
dst = texture\_sample(unit, coord, bias)
|
|
|
|
|
|
.. opcode:: DIV - Divide
|
|
|
|
.. math::
|
|
|
|
dst.x = \frac{src0.x}{src1.x}
|
|
|
|
dst.y = \frac{src0.y}{src1.y}
|
|
|
|
dst.z = \frac{src0.z}{src1.z}
|
|
|
|
dst.w = \frac{src0.w}{src1.w}
|
|
|
|
|
|
.. opcode:: DP2 - 2-component Dot Product
|
|
|
|
This instruction replicates its result.
|
|
|
|
.. math::
|
|
|
|
dst = src0.x \times src1.x + src0.y \times src1.y
|
|
|
|
|
|
.. opcode:: TEX_LZ - Texture Lookup With LOD = 0
|
|
|
|
This is the same as TXL with LOD = 0. Like every texture opcode, it obeys
|
|
pipe_sampler_view::u.tex.first_level and pipe_sampler_state::min_lod.
|
|
There is no way to override those two in shaders.
|
|
|
|
.. math::
|
|
|
|
coord.x = src0.x
|
|
|
|
coord.y = src0.y
|
|
|
|
coord.z = src0.z
|
|
|
|
coord.w = none
|
|
|
|
lod = 0
|
|
|
|
unit = src1
|
|
|
|
dst = texture\_sample(unit, coord, lod)
|
|
|
|
|
|
.. opcode:: TXL - Texture Lookup With explicit LOD
|
|
|
|
for cube map array textures, the explicit LOD value
|
|
cannot be passed in src0.w, and TXL2 must be used instead.
|
|
|
|
if the target is a shadow texture, the reference value is always
|
|
in src.z (this prevents shadow 3d / 2d array / cube targets from
|
|
using this instruction, but this is not needed).
|
|
|
|
.. math::
|
|
|
|
coord.x = src0.x
|
|
|
|
coord.y = src0.y
|
|
|
|
coord.z = src0.z
|
|
|
|
coord.w = none
|
|
|
|
lod = src0.w
|
|
|
|
unit = src1
|
|
|
|
dst = texture\_sample(unit, coord, lod)
|
|
|
|
|
|
.. opcode:: TXL2 - Texture Lookup With explicit LOD (for cube map arrays only)
|
|
|
|
this is the same as TXL, but uses another reg to encode the
|
|
explicit LOD value.
|
|
Presumably shadow 3d / 2d array / cube targets could use
|
|
this encoding too, but this is not legal.
|
|
|
|
if the target is a shadow cube map array, the reference value is in
|
|
src1.y.
|
|
|
|
.. math::
|
|
|
|
coord = src0
|
|
|
|
lod = src1.x
|
|
|
|
unit = src2
|
|
|
|
dst = texture\_sample(unit, coord, lod)
|
|
|
|
|
|
Compute ISA
|
|
^^^^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
These opcodes are primarily provided for special-use computational shaders.
|
|
Support for these opcodes indicated by a special pipe capability bit (TBD).
|
|
|
|
XXX doesn't look like most of the opcodes really belong here.
|
|
|
|
.. opcode:: CEIL - Ceiling
|
|
|
|
.. math::
|
|
|
|
dst.x = \lceil src.x\rceil
|
|
|
|
dst.y = \lceil src.y\rceil
|
|
|
|
dst.z = \lceil src.z\rceil
|
|
|
|
dst.w = \lceil src.w\rceil
|
|
|
|
|
|
.. opcode:: TRUNC - Truncate
|
|
|
|
.. math::
|
|
|
|
dst.x = trunc(src.x)
|
|
|
|
dst.y = trunc(src.y)
|
|
|
|
dst.z = trunc(src.z)
|
|
|
|
dst.w = trunc(src.w)
|
|
|
|
|
|
.. opcode:: MOD - Modulus
|
|
|
|
.. math::
|
|
|
|
dst.x = src0.x \bmod src1.x
|
|
|
|
dst.y = src0.y \bmod src1.y
|
|
|
|
dst.z = src0.z \bmod src1.z
|
|
|
|
dst.w = src0.w \bmod src1.w
|
|
|
|
|
|
.. opcode:: UARL - Integer Address Register Load
|
|
|
|
Moves the contents of the source register, assumed to be an integer, into the
|
|
destination register, which is assumed to be an address (ADDR) register.
|
|
|
|
|
|
.. opcode:: TXF - Texel Fetch
|
|
|
|
As per NV_gpu_shader4, extract a single texel from a specified texture
|
|
image or PIPE_BUFFER resource. The source sampler may not be a CUBE or
|
|
SHADOW. src 0 is a
|
|
four-component signed integer vector used to identify the single texel
|
|
accessed. 3 components + level. If the texture is multisampled, then
|
|
the fourth component indicates the sample, not the mipmap level.
|
|
Just like texture instructions, an optional
|
|
offset vector is provided, which is subject to various driver restrictions
|
|
(regarding range, source of offsets). This instruction ignores the sampler
|
|
state.
|
|
|
|
TXF(uint_vec coord, int_vec offset).
|
|
|
|
|
|
.. opcode:: TXQ - Texture Size Query
|
|
|
|
As per NV_gpu_program4, retrieve the dimensions of the texture depending on
|
|
the target. For 1D (width), 2D/RECT/CUBE (width, height), 3D (width, height,
|
|
depth), 1D array (width, layers), 2D array (width, height, layers).
|
|
Also return the number of accessible levels (last_level - first_level + 1)
|
|
in W.
|
|
|
|
For components which don't return a resource dimension, their value
|
|
is undefined.
|
|
|
|
.. math::
|
|
|
|
lod = src0.x
|
|
|
|
dst.x = texture\_width(unit, lod)
|
|
|
|
dst.y = texture\_height(unit, lod)
|
|
|
|
dst.z = texture\_depth(unit, lod)
|
|
|
|
dst.w = texture\_levels(unit)
|
|
|
|
|
|
.. opcode:: TXQS - Texture Samples Query
|
|
|
|
This retrieves the number of samples in the texture, and stores it
|
|
into the x component as an unsigned integer. The other components are
|
|
undefined. If the texture is not multisampled, this function returns
|
|
(1, undef, undef, undef).
|
|
|
|
.. math::
|
|
|
|
dst.x = texture\_samples(unit)
|
|
|
|
|
|
.. opcode:: TG4 - Texture Gather
|
|
|
|
As per ARB_texture_gather, gathers the four texels to be used in a bi-linear
|
|
filtering operation and packs them into a single register. Only works with
|
|
2D, 2D array, cubemaps, and cubemaps arrays. For 2D textures, only the
|
|
addressing modes of the sampler and the top level of any mip pyramid are
|
|
used. Set W to zero. It behaves like the TEX instruction, but a filtered
|
|
sample is not generated. The four samples that contribute to filtering are
|
|
placed into xyzw in clockwise order, starting with the (u,v) texture
|
|
coordinate delta at the following locations (-, +), (+, +), (+, -), (-, -),
|
|
where the magnitude of the deltas are half a texel.
|
|
|
|
PIPE_CAP_TEXTURE_SM5 enhances this instruction to support shadow per-sample
|
|
depth compares, single component selection, and a non-constant offset. It
|
|
doesn't allow support for the GL independent offset to get i0,j0. This would
|
|
require another CAP is hw can do it natively. For now we lower that before
|
|
TGSI.
|
|
|
|
PIPE_CAP_TGSI_TG4_COMPONENT_IN_SWIZZLE changes the encoding so that component
|
|
is stored in the sampler source swizzle x.
|
|
|
|
.. math::
|
|
|
|
coord = src0
|
|
|
|
(without TGSI_TG4_COMPONENT_IN_SWIZZLE)
|
|
component = src1
|
|
|
|
dst = texture\_gather4 (unit, coord, component)
|
|
|
|
(with TGSI_TG4_COMPONENT_IN_SWIZZLE)
|
|
dst = texture\_gather4 (unit, coord)
|
|
component is encoded in sampler swizzle.
|
|
|
|
(with SM5 - cube array shadow)
|
|
|
|
.. math::
|
|
|
|
coord = src0
|
|
|
|
compare = src1
|
|
|
|
dst = texture\_gather (uint, coord, compare)
|
|
|
|
.. opcode:: LODQ - level of detail query
|
|
|
|
Compute the LOD information that the texture pipe would use to access the
|
|
texture. The Y component contains the computed LOD lambda_prime. The X
|
|
component contains the LOD that will be accessed, based on min/max LODs
|
|
and mipmap filters.
|
|
|
|
.. math::
|
|
|
|
coord = src0
|
|
|
|
dst.xy = lodq(uint, coord);
|
|
|
|
.. opcode:: CLOCK - retrieve the current shader time
|
|
|
|
Invoking this instruction multiple times in the same shader should
|
|
cause monotonically increasing values to be returned. The values
|
|
are implicitly 64-bit, so if fewer than 64 bits of precision are
|
|
available, to provide expected wraparound semantics, the value
|
|
should be shifted up so that the most significant bit of the time
|
|
is the most significant bit of the 64-bit value.
|
|
|
|
.. math::
|
|
|
|
dst.xy = clock()
|
|
|
|
|
|
Integer ISA
|
|
^^^^^^^^^^^^^^^^^^^^^^^^
|
|
These opcodes are used for integer operations.
|
|
Support for these opcodes indicated by PIPE_SHADER_CAP_INTEGERS (all of them?)
|
|
|
|
|
|
.. opcode:: I2F - Signed Integer To Float
|
|
|
|
Rounding is unspecified (round to nearest even suggested).
|
|
|
|
.. math::
|
|
|
|
dst.x = (float) src.x
|
|
|
|
dst.y = (float) src.y
|
|
|
|
dst.z = (float) src.z
|
|
|
|
dst.w = (float) src.w
|
|
|
|
|
|
.. opcode:: U2F - Unsigned Integer To Float
|
|
|
|
Rounding is unspecified (round to nearest even suggested).
|
|
|
|
.. math::
|
|
|
|
dst.x = (float) src.x
|
|
|
|
dst.y = (float) src.y
|
|
|
|
dst.z = (float) src.z
|
|
|
|
dst.w = (float) src.w
|
|
|
|
|
|
.. opcode:: F2I - Float to Signed Integer
|
|
|
|
Rounding is towards zero (truncate).
|
|
Values outside signed range (including NaNs) produce undefined results.
|
|
|
|
.. math::
|
|
|
|
dst.x = (int) src.x
|
|
|
|
dst.y = (int) src.y
|
|
|
|
dst.z = (int) src.z
|
|
|
|
dst.w = (int) src.w
|
|
|
|
|
|
.. opcode:: F2U - Float to Unsigned Integer
|
|
|
|
Rounding is towards zero (truncate).
|
|
Values outside unsigned range (including NaNs) produce undefined results.
|
|
|
|
.. math::
|
|
|
|
dst.x = (unsigned) src.x
|
|
|
|
dst.y = (unsigned) src.y
|
|
|
|
dst.z = (unsigned) src.z
|
|
|
|
dst.w = (unsigned) src.w
|
|
|
|
|
|
.. opcode:: UADD - Integer Add
|
|
|
|
This instruction works the same for signed and unsigned integers.
|
|
The low 32bit of the result is returned.
|
|
|
|
.. math::
|
|
|
|
dst.x = src0.x + src1.x
|
|
|
|
dst.y = src0.y + src1.y
|
|
|
|
dst.z = src0.z + src1.z
|
|
|
|
dst.w = src0.w + src1.w
|
|
|
|
|
|
.. opcode:: UMAD - Integer Multiply And Add
|
|
|
|
This instruction works the same for signed and unsigned integers.
|
|
The multiplication returns the low 32bit (as does the result itself).
|
|
|
|
.. math::
|
|
|
|
dst.x = src0.x \times src1.x + src2.x
|
|
|
|
dst.y = src0.y \times src1.y + src2.y
|
|
|
|
dst.z = src0.z \times src1.z + src2.z
|
|
|
|
dst.w = src0.w \times src1.w + src2.w
|
|
|
|
|
|
.. opcode:: UMUL - Integer Multiply
|
|
|
|
This instruction works the same for signed and unsigned integers.
|
|
The low 32bit of the result is returned.
|
|
|
|
.. math::
|
|
|
|
dst.x = src0.x \times src1.x
|
|
|
|
dst.y = src0.y \times src1.y
|
|
|
|
dst.z = src0.z \times src1.z
|
|
|
|
dst.w = src0.w \times src1.w
|
|
|
|
|
|
.. opcode:: IMUL_HI - Signed Integer Multiply High Bits
|
|
|
|
The high 32bits of the multiplication of 2 signed integers are returned.
|
|
|
|
.. math::
|
|
|
|
dst.x = (src0.x \times src1.x) >> 32
|
|
|
|
dst.y = (src0.y \times src1.y) >> 32
|
|
|
|
dst.z = (src0.z \times src1.z) >> 32
|
|
|
|
dst.w = (src0.w \times src1.w) >> 32
|
|
|
|
|
|
.. opcode:: UMUL_HI - Unsigned Integer Multiply High Bits
|
|
|
|
The high 32bits of the multiplication of 2 unsigned integers are returned.
|
|
|
|
.. math::
|
|
|
|
dst.x = (src0.x \times src1.x) >> 32
|
|
|
|
dst.y = (src0.y \times src1.y) >> 32
|
|
|
|
dst.z = (src0.z \times src1.z) >> 32
|
|
|
|
dst.w = (src0.w \times src1.w) >> 32
|
|
|
|
|
|
.. opcode:: IDIV - Signed Integer Division
|
|
|
|
TBD: behavior for division by zero.
|
|
|
|
.. math::
|
|
|
|
dst.x = \frac{src0.x}{src1.x}
|
|
|
|
dst.y = \frac{src0.y}{src1.y}
|
|
|
|
dst.z = \frac{src0.z}{src1.z}
|
|
|
|
dst.w = \frac{src0.w}{src1.w}
|
|
|
|
|
|
.. opcode:: UDIV - Unsigned Integer Division
|
|
|
|
For division by zero, 0xffffffff is returned.
|
|
|
|
.. math::
|
|
|
|
dst.x = \frac{src0.x}{src1.x}
|
|
|
|
dst.y = \frac{src0.y}{src1.y}
|
|
|
|
dst.z = \frac{src0.z}{src1.z}
|
|
|
|
dst.w = \frac{src0.w}{src1.w}
|
|
|
|
|
|
.. opcode:: UMOD - Unsigned Integer Remainder
|
|
|
|
If second arg is zero, 0xffffffff is returned.
|
|
|
|
.. math::
|
|
|
|
dst.x = src0.x \bmod src1.x
|
|
|
|
dst.y = src0.y \bmod src1.y
|
|
|
|
dst.z = src0.z \bmod src1.z
|
|
|
|
dst.w = src0.w \bmod src1.w
|
|
|
|
|
|
.. opcode:: NOT - Bitwise Not
|
|
|
|
.. math::
|
|
|
|
dst.x = \sim src.x
|
|
|
|
dst.y = \sim src.y
|
|
|
|
dst.z = \sim src.z
|
|
|
|
dst.w = \sim src.w
|
|
|
|
|
|
.. opcode:: AND - Bitwise And
|
|
|
|
.. math::
|
|
|
|
dst.x = src0.x \& src1.x
|
|
|
|
dst.y = src0.y \& src1.y
|
|
|
|
dst.z = src0.z \& src1.z
|
|
|
|
dst.w = src0.w \& src1.w
|
|
|
|
|
|
.. opcode:: OR - Bitwise Or
|
|
|
|
.. math::
|
|
|
|
dst.x = src0.x | src1.x
|
|
|
|
dst.y = src0.y | src1.y
|
|
|
|
dst.z = src0.z | src1.z
|
|
|
|
dst.w = src0.w | src1.w
|
|
|
|
|
|
.. opcode:: XOR - Bitwise Xor
|
|
|
|
.. math::
|
|
|
|
dst.x = src0.x \oplus src1.x
|
|
|
|
dst.y = src0.y \oplus src1.y
|
|
|
|
dst.z = src0.z \oplus src1.z
|
|
|
|
dst.w = src0.w \oplus src1.w
|
|
|
|
|
|
.. opcode:: IMAX - Maximum of Signed Integers
|
|
|
|
.. math::
|
|
|
|
dst.x = max(src0.x, src1.x)
|
|
|
|
dst.y = max(src0.y, src1.y)
|
|
|
|
dst.z = max(src0.z, src1.z)
|
|
|
|
dst.w = max(src0.w, src1.w)
|
|
|
|
|
|
.. opcode:: UMAX - Maximum of Unsigned Integers
|
|
|
|
.. math::
|
|
|
|
dst.x = max(src0.x, src1.x)
|
|
|
|
dst.y = max(src0.y, src1.y)
|
|
|
|
dst.z = max(src0.z, src1.z)
|
|
|
|
dst.w = max(src0.w, src1.w)
|
|
|
|
|
|
.. opcode:: IMIN - Minimum of Signed Integers
|
|
|
|
.. math::
|
|
|
|
dst.x = min(src0.x, src1.x)
|
|
|
|
dst.y = min(src0.y, src1.y)
|
|
|
|
dst.z = min(src0.z, src1.z)
|
|
|
|
dst.w = min(src0.w, src1.w)
|
|
|
|
|
|
.. opcode:: UMIN - Minimum of Unsigned Integers
|
|
|
|
.. math::
|
|
|
|
dst.x = min(src0.x, src1.x)
|
|
|
|
dst.y = min(src0.y, src1.y)
|
|
|
|
dst.z = min(src0.z, src1.z)
|
|
|
|
dst.w = min(src0.w, src1.w)
|
|
|
|
|
|
.. opcode:: SHL - Shift Left
|
|
|
|
The shift count is masked with 0x1f before the shift is applied.
|
|
|
|
.. math::
|
|
|
|
dst.x = src0.x << (0x1f \& src1.x)
|
|
|
|
dst.y = src0.y << (0x1f \& src1.y)
|
|
|
|
dst.z = src0.z << (0x1f \& src1.z)
|
|
|
|
dst.w = src0.w << (0x1f \& src1.w)
|
|
|
|
|
|
.. opcode:: ISHR - Arithmetic Shift Right (of Signed Integer)
|
|
|
|
The shift count is masked with 0x1f before the shift is applied.
|
|
|
|
.. math::
|
|
|
|
dst.x = src0.x >> (0x1f \& src1.x)
|
|
|
|
dst.y = src0.y >> (0x1f \& src1.y)
|
|
|
|
dst.z = src0.z >> (0x1f \& src1.z)
|
|
|
|
dst.w = src0.w >> (0x1f \& src1.w)
|
|
|
|
|
|
.. opcode:: USHR - Logical Shift Right
|
|
|
|
The shift count is masked with 0x1f before the shift is applied.
|
|
|
|
.. math::
|
|
|
|
dst.x = src0.x >> (unsigned) (0x1f \& src1.x)
|
|
|
|
dst.y = src0.y >> (unsigned) (0x1f \& src1.y)
|
|
|
|
dst.z = src0.z >> (unsigned) (0x1f \& src1.z)
|
|
|
|
dst.w = src0.w >> (unsigned) (0x1f \& src1.w)
|
|
|
|
|
|
.. opcode:: UCMP - Integer Conditional Move
|
|
|
|
.. math::
|
|
|
|
dst.x = src0.x ? src1.x : src2.x
|
|
|
|
dst.y = src0.y ? src1.y : src2.y
|
|
|
|
dst.z = src0.z ? src1.z : src2.z
|
|
|
|
dst.w = src0.w ? src1.w : src2.w
|
|
|
|
|
|
|
|
.. opcode:: ISSG - Integer Set Sign
|
|
|
|
.. math::
|
|
|
|
dst.x = (src0.x < 0) ? -1 : (src0.x > 0) ? 1 : 0
|
|
|
|
dst.y = (src0.y < 0) ? -1 : (src0.y > 0) ? 1 : 0
|
|
|
|
dst.z = (src0.z < 0) ? -1 : (src0.z > 0) ? 1 : 0
|
|
|
|
dst.w = (src0.w < 0) ? -1 : (src0.w > 0) ? 1 : 0
|
|
|
|
|
|
|
|
.. opcode:: FSLT - Float Set On Less Than (ordered)
|
|
|
|
Same comparison as SLT but returns integer instead of 1.0/0.0 float
|
|
|
|
.. math::
|
|
|
|
dst.x = (src0.x < src1.x) ? \sim 0 : 0
|
|
|
|
dst.y = (src0.y < src1.y) ? \sim 0 : 0
|
|
|
|
dst.z = (src0.z < src1.z) ? \sim 0 : 0
|
|
|
|
dst.w = (src0.w < src1.w) ? \sim 0 : 0
|
|
|
|
|
|
.. opcode:: ISLT - Signed Integer Set On Less Than
|
|
|
|
.. math::
|
|
|
|
dst.x = (src0.x < src1.x) ? \sim 0 : 0
|
|
|
|
dst.y = (src0.y < src1.y) ? \sim 0 : 0
|
|
|
|
dst.z = (src0.z < src1.z) ? \sim 0 : 0
|
|
|
|
dst.w = (src0.w < src1.w) ? \sim 0 : 0
|
|
|
|
|
|
.. opcode:: USLT - Unsigned Integer Set On Less Than
|
|
|
|
.. math::
|
|
|
|
dst.x = (src0.x < src1.x) ? \sim 0 : 0
|
|
|
|
dst.y = (src0.y < src1.y) ? \sim 0 : 0
|
|
|
|
dst.z = (src0.z < src1.z) ? \sim 0 : 0
|
|
|
|
dst.w = (src0.w < src1.w) ? \sim 0 : 0
|
|
|
|
|
|
.. opcode:: FSGE - Float Set On Greater Equal Than (ordered)
|
|
|
|
Same comparison as SGE but returns integer instead of 1.0/0.0 float
|
|
|
|
.. math::
|
|
|
|
dst.x = (src0.x >= src1.x) ? \sim 0 : 0
|
|
|
|
dst.y = (src0.y >= src1.y) ? \sim 0 : 0
|
|
|
|
dst.z = (src0.z >= src1.z) ? \sim 0 : 0
|
|
|
|
dst.w = (src0.w >= src1.w) ? \sim 0 : 0
|
|
|
|
|
|
.. opcode:: ISGE - Signed Integer Set On Greater Equal Than
|
|
|
|
.. math::
|
|
|
|
dst.x = (src0.x >= src1.x) ? \sim 0 : 0
|
|
|
|
dst.y = (src0.y >= src1.y) ? \sim 0 : 0
|
|
|
|
dst.z = (src0.z >= src1.z) ? \sim 0 : 0
|
|
|
|
dst.w = (src0.w >= src1.w) ? \sim 0 : 0
|
|
|
|
|
|
.. opcode:: USGE - Unsigned Integer Set On Greater Equal Than
|
|
|
|
.. math::
|
|
|
|
dst.x = (src0.x >= src1.x) ? \sim 0 : 0
|
|
|
|
dst.y = (src0.y >= src1.y) ? \sim 0 : 0
|
|
|
|
dst.z = (src0.z >= src1.z) ? \sim 0 : 0
|
|
|
|
dst.w = (src0.w >= src1.w) ? \sim 0 : 0
|
|
|
|
|
|
.. opcode:: FSEQ - Float Set On Equal (ordered)
|
|
|
|
Same comparison as SEQ but returns integer instead of 1.0/0.0 float
|
|
|
|
.. math::
|
|
|
|
dst.x = (src0.x == src1.x) ? \sim 0 : 0
|
|
|
|
dst.y = (src0.y == src1.y) ? \sim 0 : 0
|
|
|
|
dst.z = (src0.z == src1.z) ? \sim 0 : 0
|
|
|
|
dst.w = (src0.w == src1.w) ? \sim 0 : 0
|
|
|
|
|
|
.. opcode:: USEQ - Integer Set On Equal
|
|
|
|
.. math::
|
|
|
|
dst.x = (src0.x == src1.x) ? \sim 0 : 0
|
|
|
|
dst.y = (src0.y == src1.y) ? \sim 0 : 0
|
|
|
|
dst.z = (src0.z == src1.z) ? \sim 0 : 0
|
|
|
|
dst.w = (src0.w == src1.w) ? \sim 0 : 0
|
|
|
|
|
|
.. opcode:: FSNE - Float Set On Not Equal (unordered)
|
|
|
|
Same comparison as SNE but returns integer instead of 1.0/0.0 float
|
|
|
|
.. math::
|
|
|
|
dst.x = (src0.x != src1.x) ? \sim 0 : 0
|
|
|
|
dst.y = (src0.y != src1.y) ? \sim 0 : 0
|
|
|
|
dst.z = (src0.z != src1.z) ? \sim 0 : 0
|
|
|
|
dst.w = (src0.w != src1.w) ? \sim 0 : 0
|
|
|
|
|
|
.. opcode:: USNE - Integer Set On Not Equal
|
|
|
|
.. math::
|
|
|
|
dst.x = (src0.x != src1.x) ? \sim 0 : 0
|
|
|
|
dst.y = (src0.y != src1.y) ? \sim 0 : 0
|
|
|
|
dst.z = (src0.z != src1.z) ? \sim 0 : 0
|
|
|
|
dst.w = (src0.w != src1.w) ? \sim 0 : 0
|
|
|
|
|
|
.. opcode:: INEG - Integer Negate
|
|
|
|
Two's complement.
|
|
|
|
.. math::
|
|
|
|
dst.x = -src.x
|
|
|
|
dst.y = -src.y
|
|
|
|
dst.z = -src.z
|
|
|
|
dst.w = -src.w
|
|
|
|
|
|
.. opcode:: IABS - Integer Absolute Value
|
|
|
|
.. math::
|
|
|
|
dst.x = |src.x|
|
|
|
|
dst.y = |src.y|
|
|
|
|
dst.z = |src.z|
|
|
|
|
dst.w = |src.w|
|
|
|
|
Bitwise ISA
|
|
^^^^^^^^^^^
|
|
These opcodes are used for bit-level manipulation of integers.
|
|
|
|
.. opcode:: IBFE - Signed Bitfield Extract
|
|
|
|
Like GLSL bitfieldExtract. Extracts a set of bits from the input, and
|
|
sign-extends them if the high bit of the extracted window is set.
|
|
|
|
Pseudocode::
|
|
|
|
def ibfe(value, offset, bits):
|
|
if offset < 0 or bits < 0 or offset + bits > 32:
|
|
return undefined
|
|
if bits == 0: return 0
|
|
# Note: >> sign-extends
|
|
return (value << (32 - offset - bits)) >> (32 - bits)
|
|
|
|
.. opcode:: UBFE - Unsigned Bitfield Extract
|
|
|
|
Like GLSL bitfieldExtract. Extracts a set of bits from the input, without
|
|
any sign-extension.
|
|
|
|
Pseudocode::
|
|
|
|
def ubfe(value, offset, bits):
|
|
if offset < 0 or bits < 0 or offset + bits > 32:
|
|
return undefined
|
|
if bits == 0: return 0
|
|
# Note: >> does not sign-extend
|
|
return (value << (32 - offset - bits)) >> (32 - bits)
|
|
|
|
.. opcode:: BFI - Bitfield Insert
|
|
|
|
Like GLSL bitfieldInsert. Replaces a bit region of 'base' with the low bits
|
|
of 'insert'.
|
|
|
|
Pseudocode::
|
|
|
|
def bfi(base, insert, offset, bits):
|
|
if offset < 0 or bits < 0 or offset + bits > 32:
|
|
return undefined
|
|
# << defined such that mask == ~0 when bits == 32, offset == 0
|
|
mask = ((1 << bits) - 1) << offset
|
|
return ((insert << offset) & mask) | (base & ~mask)
|
|
|
|
.. opcode:: BREV - Bitfield Reverse
|
|
|
|
See SM5 instruction BFREV. Reverses the bits of the argument.
|
|
|
|
.. opcode:: POPC - Population Count
|
|
|
|
See SM5 instruction COUNTBITS. Counts the number of set bits in the argument.
|
|
|
|
.. opcode:: LSB - Index of lowest set bit
|
|
|
|
See SM5 instruction FIRSTBIT_LO. Computes the 0-based index of the first set
|
|
bit of the argument. Returns -1 if none are set.
|
|
|
|
.. opcode:: IMSB - Index of highest non-sign bit
|
|
|
|
See SM5 instruction FIRSTBIT_SHI. Computes the 0-based index of the highest
|
|
non-sign bit of the argument (i.e. highest 0 bit for negative numbers,
|
|
highest 1 bit for positive numbers). Returns -1 if all bits are the same
|
|
(i.e. for inputs 0 and -1).
|
|
|
|
.. opcode:: UMSB - Index of highest set bit
|
|
|
|
See SM5 instruction FIRSTBIT_HI. Computes the 0-based index of the highest
|
|
set bit of the argument. Returns -1 if none are set.
|
|
|
|
Geometry ISA
|
|
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
These opcodes are only supported in geometry shaders; they have no meaning
|
|
in any other type of shader.
|
|
|
|
.. opcode:: EMIT - Emit
|
|
|
|
Generate a new vertex for the current primitive into the specified vertex
|
|
stream using the values in the output registers.
|
|
|
|
|
|
.. opcode:: ENDPRIM - End Primitive
|
|
|
|
Complete the current primitive in the specified vertex stream (consisting of
|
|
the emitted vertices), and start a new one.
|
|
|
|
|
|
GLSL ISA
|
|
^^^^^^^^^^
|
|
|
|
These opcodes are part of :term:`GLSL`'s opcode set. Support for these
|
|
opcodes is determined by a special capability bit, ``GLSL``.
|
|
Some require glsl version 1.30 (UIF/SWITCH/CASE/DEFAULT/ENDSWITCH).
|
|
|
|
.. opcode:: CAL - Subroutine Call
|
|
|
|
push(pc)
|
|
pc = target
|
|
|
|
|
|
.. opcode:: RET - Subroutine Call Return
|
|
|
|
pc = pop()
|
|
|
|
|
|
.. opcode:: CONT - Continue
|
|
|
|
Unconditionally moves the point of execution to the instruction after the
|
|
last bgnloop. The instruction must appear within a bgnloop/endloop.
|
|
|
|
.. note::
|
|
|
|
Support for CONT is determined by a special capability bit,
|
|
``TGSI_CONT_SUPPORTED``. See :ref:`Screen` for more information.
|
|
|
|
|
|
.. opcode:: BGNLOOP - Begin a Loop
|
|
|
|
Start a loop. Must have a matching endloop.
|
|
|
|
|
|
.. opcode:: BGNSUB - Begin Subroutine
|
|
|
|
Starts definition of a subroutine. Must have a matching endsub.
|
|
|
|
|
|
.. opcode:: ENDLOOP - End a Loop
|
|
|
|
End a loop started with bgnloop.
|
|
|
|
|
|
.. opcode:: ENDSUB - End Subroutine
|
|
|
|
Ends definition of a subroutine.
|
|
|
|
|
|
.. opcode:: NOP - No Operation
|
|
|
|
Do nothing.
|
|
|
|
|
|
.. opcode:: BRK - Break
|
|
|
|
Unconditionally moves the point of execution to the instruction after the
|
|
next endloop or endswitch. The instruction must appear within a loop/endloop
|
|
or switch/endswitch.
|
|
|
|
|
|
.. opcode:: IF - Float If
|
|
|
|
Start an IF ... ELSE .. ENDIF block. Condition evaluates to true if
|
|
|
|
src0.x != 0.0
|
|
|
|
where src0.x is interpreted as a floating point register.
|
|
|
|
|
|
.. opcode:: UIF - Bitwise If
|
|
|
|
Start an UIF ... ELSE .. ENDIF block. Condition evaluates to true if
|
|
|
|
src0.x != 0
|
|
|
|
where src0.x is interpreted as an integer register.
|
|
|
|
|
|
.. opcode:: ELSE - Else
|
|
|
|
Starts an else block, after an IF or UIF statement.
|
|
|
|
|
|
.. opcode:: ENDIF - End If
|
|
|
|
Ends an IF or UIF block.
|
|
|
|
|
|
.. opcode:: SWITCH - Switch
|
|
|
|
Starts a C-style switch expression. The switch consists of one or multiple
|
|
CASE statements, and at most one DEFAULT statement. Execution of a statement
|
|
ends when a BRK is hit, but just like in C falling through to other cases
|
|
without a break is allowed. Similarly, DEFAULT label is allowed anywhere not
|
|
just as last statement, and fallthrough is allowed into/from it.
|
|
CASE src arguments are evaluated at bit level against the SWITCH src argument.
|
|
|
|
Example::
|
|
|
|
SWITCH src[0].x
|
|
CASE src[0].x
|
|
(some instructions here)
|
|
(optional BRK here)
|
|
DEFAULT
|
|
(some instructions here)
|
|
(optional BRK here)
|
|
CASE src[0].x
|
|
(some instructions here)
|
|
(optional BRK here)
|
|
ENDSWITCH
|
|
|
|
|
|
.. opcode:: CASE - Switch case
|
|
|
|
This represents a switch case label. The src arg must be an integer immediate.
|
|
|
|
|
|
.. opcode:: DEFAULT - Switch default
|
|
|
|
This represents the default case in the switch, which is taken if no other
|
|
case matches.
|
|
|
|
|
|
.. opcode:: ENDSWITCH - End of switch
|
|
|
|
Ends a switch expression.
|
|
|
|
|
|
Interpolation ISA
|
|
^^^^^^^^^^^^^^^^^
|
|
|
|
The interpolation instructions allow an input to be interpolated in a
|
|
different way than its declaration. This corresponds to the GLSL 4.00
|
|
interpolateAt* functions. The first argument of each of these must come from
|
|
``TGSI_FILE_INPUT``.
|
|
|
|
.. opcode:: INTERP_CENTROID - Interpolate at the centroid
|
|
|
|
Interpolates the varying specified by src0 at the centroid
|
|
|
|
.. opcode:: INTERP_SAMPLE - Interpolate at the specified sample
|
|
|
|
Interpolates the varying specified by src0 at the sample id specified by
|
|
src1.x (interpreted as an integer)
|
|
|
|
.. opcode:: INTERP_OFFSET - Interpolate at the specified offset
|
|
|
|
Interpolates the varying specified by src0 at the offset src1.xy from the
|
|
pixel center (interpreted as floats)
|
|
|
|
|
|
.. _doubleopcodes:
|
|
|
|
Double ISA
|
|
^^^^^^^^^^^^^^^
|
|
|
|
The double-precision opcodes reinterpret four-component vectors into
|
|
two-component vectors with doubled precision in each component.
|
|
|
|
.. opcode:: DABS - Absolute
|
|
|
|
.. math::
|
|
|
|
dst.xy = |src0.xy|
|
|
|
|
dst.zw = |src0.zw|
|
|
|
|
.. opcode:: DADD - Add
|
|
|
|
.. math::
|
|
|
|
dst.xy = src0.xy + src1.xy
|
|
|
|
dst.zw = src0.zw + src1.zw
|
|
|
|
.. opcode:: DSEQ - Set on Equal
|
|
|
|
.. math::
|
|
|
|
dst.x = src0.xy == src1.xy ? \sim 0 : 0
|
|
|
|
dst.z = src0.zw == src1.zw ? \sim 0 : 0
|
|
|
|
.. opcode:: DSNE - Set on Not Equal
|
|
|
|
.. math::
|
|
|
|
dst.x = src0.xy != src1.xy ? \sim 0 : 0
|
|
|
|
dst.z = src0.zw != src1.zw ? \sim 0 : 0
|
|
|
|
.. opcode:: DSLT - Set on Less than
|
|
|
|
.. math::
|
|
|
|
dst.x = src0.xy < src1.xy ? \sim 0 : 0
|
|
|
|
dst.z = src0.zw < src1.zw ? \sim 0 : 0
|
|
|
|
.. opcode:: DSGE - Set on Greater equal
|
|
|
|
.. math::
|
|
|
|
dst.x = src0.xy >= src1.xy ? \sim 0 : 0
|
|
|
|
dst.z = src0.zw >= src1.zw ? \sim 0 : 0
|
|
|
|
.. opcode:: DFRAC - Fraction
|
|
|
|
.. math::
|
|
|
|
dst.xy = src.xy - \lfloor src.xy\rfloor
|
|
|
|
dst.zw = src.zw - \lfloor src.zw\rfloor
|
|
|
|
.. opcode:: DTRUNC - Truncate
|
|
|
|
.. math::
|
|
|
|
dst.xy = trunc(src.xy)
|
|
|
|
dst.zw = trunc(src.zw)
|
|
|
|
.. opcode:: DCEIL - Ceiling
|
|
|
|
.. math::
|
|
|
|
dst.xy = \lceil src.xy\rceil
|
|
|
|
dst.zw = \lceil src.zw\rceil
|
|
|
|
.. opcode:: DFLR - Floor
|
|
|
|
.. math::
|
|
|
|
dst.xy = \lfloor src.xy\rfloor
|
|
|
|
dst.zw = \lfloor src.zw\rfloor
|
|
|
|
.. opcode:: DROUND - Fraction
|
|
|
|
.. math::
|
|
|
|
dst.xy = round(src.xy)
|
|
|
|
dst.zw = round(src.zw)
|
|
|
|
.. opcode:: DSSG - Set Sign
|
|
|
|
.. math::
|
|
|
|
dst.xy = (src.xy > 0) ? 1.0 : (src.xy < 0) ? -1.0 : 0.0
|
|
|
|
dst.zw = (src.zw > 0) ? 1.0 : (src.zw < 0) ? -1.0 : 0.0
|
|
|
|
.. opcode:: DFRACEXP - Convert Number to Fractional and Integral Components
|
|
|
|
Like the ``frexp()`` routine in many math libraries, this opcode stores the
|
|
exponent of its source to ``dst0``, and the significand to ``dst1``, such that
|
|
:math:`dst1 \times 2^{dst0} = src` . The results are replicated across
|
|
channels.
|
|
|
|
.. math::
|
|
|
|
dst0.xy = dst.zw = frac(src.xy)
|
|
|
|
dst1 = frac(src.xy)
|
|
|
|
|
|
.. opcode:: DLDEXP - Multiply Number by Integral Power of 2
|
|
|
|
This opcode is the inverse of :opcode:`DFRACEXP`. The second
|
|
source is an integer.
|
|
|
|
.. math::
|
|
|
|
dst.xy = src0.xy \times 2^{src1.x}
|
|
|
|
dst.zw = src0.zw \times 2^{src1.z}
|
|
|
|
.. opcode:: DMIN - Minimum
|
|
|
|
.. math::
|
|
|
|
dst.xy = min(src0.xy, src1.xy)
|
|
|
|
dst.zw = min(src0.zw, src1.zw)
|
|
|
|
.. opcode:: DMAX - Maximum
|
|
|
|
.. math::
|
|
|
|
dst.xy = max(src0.xy, src1.xy)
|
|
|
|
dst.zw = max(src0.zw, src1.zw)
|
|
|
|
.. opcode:: DMUL - Multiply
|
|
|
|
.. math::
|
|
|
|
dst.xy = src0.xy \times src1.xy
|
|
|
|
dst.zw = src0.zw \times src1.zw
|
|
|
|
|
|
.. opcode:: DMAD - Multiply And Add
|
|
|
|
.. math::
|
|
|
|
dst.xy = src0.xy \times src1.xy + src2.xy
|
|
|
|
dst.zw = src0.zw \times src1.zw + src2.zw
|
|
|
|
|
|
.. opcode:: DFMA - Fused Multiply-Add
|
|
|
|
Perform a * b + c with no intermediate rounding step.
|
|
|
|
.. math::
|
|
|
|
dst.xy = src0.xy \times src1.xy + src2.xy
|
|
|
|
dst.zw = src0.zw \times src1.zw + src2.zw
|
|
|
|
|
|
.. opcode:: DDIV - Divide
|
|
|
|
.. math::
|
|
|
|
dst.xy = \frac{src0.xy}{src1.xy}
|
|
|
|
dst.zw = \frac{src0.zw}{src1.zw}
|
|
|
|
|
|
.. opcode:: DRCP - Reciprocal
|
|
|
|
.. math::
|
|
|
|
dst.xy = \frac{1}{src.xy}
|
|
|
|
dst.zw = \frac{1}{src.zw}
|
|
|
|
.. opcode:: DSQRT - Square Root
|
|
|
|
.. math::
|
|
|
|
dst.xy = \sqrt{src.xy}
|
|
|
|
dst.zw = \sqrt{src.zw}
|
|
|
|
.. opcode:: DRSQ - Reciprocal Square Root
|
|
|
|
.. math::
|
|
|
|
dst.xy = \frac{1}{\sqrt{src.xy}}
|
|
|
|
dst.zw = \frac{1}{\sqrt{src.zw}}
|
|
|
|
.. opcode:: F2D - Float to Double
|
|
|
|
.. math::
|
|
|
|
dst.xy = double(src0.x)
|
|
|
|
dst.zw = double(src0.y)
|
|
|
|
.. opcode:: D2F - Double to Float
|
|
|
|
.. math::
|
|
|
|
dst.x = float(src0.xy)
|
|
|
|
dst.y = float(src0.zw)
|
|
|
|
.. opcode:: I2D - Int to Double
|
|
|
|
.. math::
|
|
|
|
dst.xy = double(src0.x)
|
|
|
|
dst.zw = double(src0.y)
|
|
|
|
.. opcode:: D2I - Double to Int
|
|
|
|
.. math::
|
|
|
|
dst.x = int(src0.xy)
|
|
|
|
dst.y = int(src0.zw)
|
|
|
|
.. opcode:: U2D - Unsigned Int to Double
|
|
|
|
.. math::
|
|
|
|
dst.xy = double(src0.x)
|
|
|
|
dst.zw = double(src0.y)
|
|
|
|
.. opcode:: D2U - Double to Unsigned Int
|
|
|
|
.. math::
|
|
|
|
dst.x = unsigned(src0.xy)
|
|
|
|
dst.y = unsigned(src0.zw)
|
|
|
|
64-bit Integer ISA
|
|
^^^^^^^^^^^^^^^^^^
|
|
|
|
The 64-bit integer opcodes reinterpret four-component vectors into
|
|
two-component vectors with 64-bits in each component.
|
|
|
|
.. opcode:: I64ABS - 64-bit Integer Absolute Value
|
|
|
|
.. math::
|
|
|
|
dst.xy = |src0.xy|
|
|
|
|
dst.zw = |src0.zw|
|
|
|
|
.. opcode:: I64NEG - 64-bit Integer Negate
|
|
|
|
Two's complement.
|
|
|
|
.. math::
|
|
|
|
dst.xy = -src.xy
|
|
|
|
dst.zw = -src.zw
|
|
|
|
.. opcode:: I64SSG - 64-bit Integer Set Sign
|
|
|
|
.. math::
|
|
|
|
dst.xy = (src0.xy < 0) ? -1 : (src0.xy > 0) ? 1 : 0
|
|
|
|
dst.zw = (src0.zw < 0) ? -1 : (src0.zw > 0) ? 1 : 0
|
|
|
|
.. opcode:: U64ADD - 64-bit Integer Add
|
|
|
|
.. math::
|
|
|
|
dst.xy = src0.xy + src1.xy
|
|
|
|
dst.zw = src0.zw + src1.zw
|
|
|
|
.. opcode:: U64MUL - 64-bit Integer Multiply
|
|
|
|
.. math::
|
|
|
|
dst.xy = src0.xy * src1.xy
|
|
|
|
dst.zw = src0.zw * src1.zw
|
|
|
|
.. opcode:: U64SEQ - 64-bit Integer Set on Equal
|
|
|
|
.. math::
|
|
|
|
dst.x = src0.xy == src1.xy ? \sim 0 : 0
|
|
|
|
dst.z = src0.zw == src1.zw ? \sim 0 : 0
|
|
|
|
.. opcode:: U64SNE - 64-bit Integer Set on Not Equal
|
|
|
|
.. math::
|
|
|
|
dst.x = src0.xy != src1.xy ? \sim 0 : 0
|
|
|
|
dst.z = src0.zw != src1.zw ? \sim 0 : 0
|
|
|
|
.. opcode:: U64SLT - 64-bit Unsigned Integer Set on Less Than
|
|
|
|
.. math::
|
|
|
|
dst.x = src0.xy < src1.xy ? \sim 0 : 0
|
|
|
|
dst.z = src0.zw < src1.zw ? \sim 0 : 0
|
|
|
|
.. opcode:: U64SGE - 64-bit Unsigned Integer Set on Greater Equal
|
|
|
|
.. math::
|
|
|
|
dst.x = src0.xy >= src1.xy ? \sim 0 : 0
|
|
|
|
dst.z = src0.zw >= src1.zw ? \sim 0 : 0
|
|
|
|
.. opcode:: I64SLT - 64-bit Signed Integer Set on Less Than
|
|
|
|
.. math::
|
|
|
|
dst.x = src0.xy < src1.xy ? \sim 0 : 0
|
|
|
|
dst.z = src0.zw < src1.zw ? \sim 0 : 0
|
|
|
|
.. opcode:: I64SGE - 64-bit Signed Integer Set on Greater Equal
|
|
|
|
.. math::
|
|
|
|
dst.x = src0.xy >= src1.xy ? \sim 0 : 0
|
|
|
|
dst.z = src0.zw >= src1.zw ? \sim 0 : 0
|
|
|
|
.. opcode:: I64MIN - Minimum of 64-bit Signed Integers
|
|
|
|
.. math::
|
|
|
|
dst.xy = min(src0.xy, src1.xy)
|
|
|
|
dst.zw = min(src0.zw, src1.zw)
|
|
|
|
.. opcode:: U64MIN - Minimum of 64-bit Unsigned Integers
|
|
|
|
.. math::
|
|
|
|
dst.xy = min(src0.xy, src1.xy)
|
|
|
|
dst.zw = min(src0.zw, src1.zw)
|
|
|
|
.. opcode:: I64MAX - Maximum of 64-bit Signed Integers
|
|
|
|
.. math::
|
|
|
|
dst.xy = max(src0.xy, src1.xy)
|
|
|
|
dst.zw = max(src0.zw, src1.zw)
|
|
|
|
.. opcode:: U64MAX - Maximum of 64-bit Unsigned Integers
|
|
|
|
.. math::
|
|
|
|
dst.xy = max(src0.xy, src1.xy)
|
|
|
|
dst.zw = max(src0.zw, src1.zw)
|
|
|
|
.. opcode:: U64SHL - Shift Left 64-bit Unsigned Integer
|
|
|
|
The shift count is masked with 0x3f before the shift is applied.
|
|
|
|
.. math::
|
|
|
|
dst.xy = src0.xy << (0x3f \& src1.x)
|
|
|
|
dst.zw = src0.zw << (0x3f \& src1.y)
|
|
|
|
.. opcode:: I64SHR - Arithmetic Shift Right (of 64-bit Signed Integer)
|
|
|
|
The shift count is masked with 0x3f before the shift is applied.
|
|
|
|
.. math::
|
|
|
|
dst.xy = src0.xy >> (0x3f \& src1.x)
|
|
|
|
dst.zw = src0.zw >> (0x3f \& src1.y)
|
|
|
|
.. opcode:: U64SHR - Logical Shift Right (of 64-bit Unsigned Integer)
|
|
|
|
The shift count is masked with 0x3f before the shift is applied.
|
|
|
|
.. math::
|
|
|
|
dst.xy = src0.xy >> (unsigned) (0x3f \& src1.x)
|
|
|
|
dst.zw = src0.zw >> (unsigned) (0x3f \& src1.y)
|
|
|
|
.. opcode:: I64DIV - 64-bit Signed Integer Division
|
|
|
|
.. math::
|
|
|
|
dst.xy = \frac{src0.xy}{src1.xy}
|
|
|
|
dst.zw = \frac{src0.zw}{src1.zw}
|
|
|
|
.. opcode:: U64DIV - 64-bit Unsigned Integer Division
|
|
|
|
.. math::
|
|
|
|
dst.xy = \frac{src0.xy}{src1.xy}
|
|
|
|
dst.zw = \frac{src0.zw}{src1.zw}
|
|
|
|
.. opcode:: U64MOD - 64-bit Unsigned Integer Remainder
|
|
|
|
.. math::
|
|
|
|
dst.xy = src0.xy \bmod src1.xy
|
|
|
|
dst.zw = src0.zw \bmod src1.zw
|
|
|
|
.. opcode:: I64MOD - 64-bit Signed Integer Remainder
|
|
|
|
.. math::
|
|
|
|
dst.xy = src0.xy \bmod src1.xy
|
|
|
|
dst.zw = src0.zw \bmod src1.zw
|
|
|
|
.. opcode:: F2U64 - Float to 64-bit Unsigned Int
|
|
|
|
.. math::
|
|
|
|
dst.xy = (uint64_t) src0.x
|
|
|
|
dst.zw = (uint64_t) src0.y
|
|
|
|
.. opcode:: F2I64 - Float to 64-bit Int
|
|
|
|
.. math::
|
|
|
|
dst.xy = (int64_t) src0.x
|
|
|
|
dst.zw = (int64_t) src0.y
|
|
|
|
.. opcode:: U2I64 - Unsigned Integer to 64-bit Integer
|
|
|
|
This is a zero extension.
|
|
|
|
.. math::
|
|
|
|
dst.xy = (int64_t) src0.x
|
|
|
|
dst.zw = (int64_t) src0.y
|
|
|
|
.. opcode:: I2I64 - Signed Integer to 64-bit Integer
|
|
|
|
This is a sign extension.
|
|
|
|
.. math::
|
|
|
|
dst.xy = (int64_t) src0.x
|
|
|
|
dst.zw = (int64_t) src0.y
|
|
|
|
.. opcode:: D2U64 - Double to 64-bit Unsigned Int
|
|
|
|
.. math::
|
|
|
|
dst.xy = (uint64_t) src0.xy
|
|
|
|
dst.zw = (uint64_t) src0.zw
|
|
|
|
.. opcode:: D2I64 - Double to 64-bit Int
|
|
|
|
.. math::
|
|
|
|
dst.xy = (int64_t) src0.xy
|
|
|
|
dst.zw = (int64_t) src0.zw
|
|
|
|
.. opcode:: U642F - 64-bit unsigned integer to float
|
|
|
|
.. math::
|
|
|
|
dst.x = (float) src0.xy
|
|
|
|
dst.y = (float) src0.zw
|
|
|
|
.. opcode:: I642F - 64-bit Int to Float
|
|
|
|
.. math::
|
|
|
|
dst.x = (float) src0.xy
|
|
|
|
dst.y = (float) src0.zw
|
|
|
|
.. opcode:: U642D - 64-bit unsigned integer to double
|
|
|
|
.. math::
|
|
|
|
dst.xy = (double) src0.xy
|
|
|
|
dst.zw = (double) src0.zw
|
|
|
|
.. opcode:: I642D - 64-bit Int to double
|
|
|
|
.. math::
|
|
|
|
dst.xy = (double) src0.xy
|
|
|
|
dst.zw = (double) src0.zw
|
|
|
|
.. _samplingopcodes:
|
|
|
|
Resource Sampling Opcodes
|
|
^^^^^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
Those opcodes follow very closely semantics of the respective Direct3D
|
|
instructions. If in doubt double check Direct3D documentation.
|
|
Note that the swizzle on SVIEW (src1) determines texel swizzling
|
|
after lookup.
|
|
|
|
.. opcode:: SAMPLE
|
|
|
|
Using provided address, sample data from the specified texture using the
|
|
filtering mode identified by the given sampler. The source data may come from
|
|
any resource type other than buffers.
|
|
|
|
Syntax: ``SAMPLE dst, address, sampler_view, sampler``
|
|
|
|
Example: ``SAMPLE TEMP[0], TEMP[1], SVIEW[0], SAMP[0]``
|
|
|
|
.. opcode:: SAMPLE_I
|
|
|
|
Simplified alternative to the SAMPLE instruction. Using the provided
|
|
integer address, SAMPLE_I fetches data from the specified sampler view
|
|
without any filtering. The source data may come from any resource type
|
|
other than CUBE.
|
|
|
|
Syntax: ``SAMPLE_I dst, address, sampler_view``
|
|
|
|
Example: ``SAMPLE_I TEMP[0], TEMP[1], SVIEW[0]``
|
|
|
|
The 'address' is specified as unsigned integers. If the 'address' is out of
|
|
range [0...(# texels - 1)] the result of the fetch is always 0 in all
|
|
components. As such the instruction doesn't honor address wrap modes, in
|
|
cases where that behavior is desirable 'SAMPLE' instruction should be used.
|
|
address.w always provides an unsigned integer mipmap level. If the value is
|
|
out of the range then the instruction always returns 0 in all components.
|
|
address.yz are ignored for buffers and 1d textures. address.z is ignored
|
|
for 1d texture arrays and 2d textures.
|
|
|
|
For 1D texture arrays address.y provides the array index (also as unsigned
|
|
integer). If the value is out of the range of available array indices
|
|
[0... (array size - 1)] then the opcode always returns 0 in all components.
|
|
For 2D texture arrays address.z provides the array index, otherwise it
|
|
exhibits the same behavior as in the case for 1D texture arrays. The exact
|
|
semantics of the source address are presented in the table below:
|
|
|
|
+---------------------------+----+-----+-----+---------+
|
|
| resource type | X | Y | Z | W |
|
|
+===========================+====+=====+=====+=========+
|
|
| ``PIPE_BUFFER`` | x | | | ignored |
|
|
+---------------------------+----+-----+-----+---------+
|
|
| ``PIPE_TEXTURE_1D`` | x | | | mpl |
|
|
+---------------------------+----+-----+-----+---------+
|
|
| ``PIPE_TEXTURE_2D`` | x | y | | mpl |
|
|
+---------------------------+----+-----+-----+---------+
|
|
| ``PIPE_TEXTURE_3D`` | x | y | z | mpl |
|
|
+---------------------------+----+-----+-----+---------+
|
|
| ``PIPE_TEXTURE_RECT`` | x | y | | mpl |
|
|
+---------------------------+----+-----+-----+---------+
|
|
| ``PIPE_TEXTURE_CUBE`` | not allowed as source |
|
|
+---------------------------+----+-----+-----+---------+
|
|
| ``PIPE_TEXTURE_1D_ARRAY`` | x | idx | | mpl |
|
|
+---------------------------+----+-----+-----+---------+
|
|
| ``PIPE_TEXTURE_2D_ARRAY`` | x | y | idx | mpl |
|
|
+---------------------------+----+-----+-----+---------+
|
|
|
|
Where 'mpl' is a mipmap level and 'idx' is the array index.
|
|
|
|
.. opcode:: SAMPLE_I_MS
|
|
|
|
Just like SAMPLE_I but allows fetch data from multi-sampled surfaces.
|
|
|
|
Syntax: ``SAMPLE_I_MS dst, address, sampler_view, sample``
|
|
|
|
.. opcode:: SAMPLE_B
|
|
|
|
Just like the SAMPLE instruction with the exception that an additional bias
|
|
is applied to the level of detail computed as part of the instruction
|
|
execution.
|
|
|
|
Syntax: ``SAMPLE_B dst, address, sampler_view, sampler, lod_bias``
|
|
|
|
Example: ``SAMPLE_B TEMP[0], TEMP[1], SVIEW[0], SAMP[0], TEMP[2].x``
|
|
|
|
.. opcode:: SAMPLE_C
|
|
|
|
Similar to the SAMPLE instruction but it performs a comparison filter. The
|
|
operands to SAMPLE_C are identical to SAMPLE, except that there is an
|
|
additional float32 operand, reference value, which must be a register with
|
|
single-component, or a scalar literal. SAMPLE_C makes the hardware use the
|
|
current samplers compare_func (in pipe_sampler_state) to compare reference
|
|
value against the red component value for the surce resource at each texel
|
|
that the currently configured texture filter covers based on the provided
|
|
coordinates.
|
|
|
|
Syntax: ``SAMPLE_C dst, address, sampler_view.r, sampler, ref_value``
|
|
|
|
Example: ``SAMPLE_C TEMP[0], TEMP[1], SVIEW[0].r, SAMP[0], TEMP[2].x``
|
|
|
|
.. opcode:: SAMPLE_C_LZ
|
|
|
|
Same as SAMPLE_C, but LOD is 0 and derivatives are ignored. The LZ stands
|
|
for level-zero.
|
|
|
|
Syntax: ``SAMPLE_C_LZ dst, address, sampler_view.r, sampler, ref_value``
|
|
|
|
Example: ``SAMPLE_C_LZ TEMP[0], TEMP[1], SVIEW[0].r, SAMP[0], TEMP[2].x``
|
|
|
|
|
|
.. opcode:: SAMPLE_D
|
|
|
|
SAMPLE_D is identical to the SAMPLE opcode except that the derivatives for
|
|
the source address in the x direction and the y direction are provided by
|
|
extra parameters.
|
|
|
|
Syntax: ``SAMPLE_D dst, address, sampler_view, sampler, der_x, der_y``
|
|
|
|
Example: ``SAMPLE_D TEMP[0], TEMP[1], SVIEW[0], SAMP[0], TEMP[2], TEMP[3]``
|
|
|
|
.. opcode:: SAMPLE_L
|
|
|
|
SAMPLE_L is identical to the SAMPLE opcode except that the LOD is provided
|
|
directly as a scalar value, representing no anisotropy.
|
|
|
|
Syntax: ``SAMPLE_L dst, address, sampler_view, sampler, explicit_lod``
|
|
|
|
Example: ``SAMPLE_L TEMP[0], TEMP[1], SVIEW[0], SAMP[0], TEMP[2].x``
|
|
|
|
.. opcode:: GATHER4
|
|
|
|
Gathers the four texels to be used in a bi-linear filtering operation and
|
|
packs them into a single register. Only works with 2D, 2D array, cubemaps,
|
|
and cubemaps arrays. For 2D textures, only the addressing modes of the
|
|
sampler and the top level of any mip pyramid are used. Set W to zero. It
|
|
behaves like the SAMPLE instruction, but a filtered sample is not
|
|
generated. The four samples that contribute to filtering are placed into
|
|
xyzw in counter-clockwise order, starting with the (u,v) texture coordinate
|
|
delta at the following locations (-, +), (+, +), (+, -), (-, -), where the
|
|
magnitude of the deltas are half a texel.
|
|
|
|
|
|
.. opcode:: SVIEWINFO
|
|
|
|
Query the dimensions of a given sampler view. dst receives width, height,
|
|
depth or array size and number of mipmap levels as int4. The dst can have a
|
|
writemask which will specify what info is the caller interested in.
|
|
|
|
Syntax: ``SVIEWINFO dst, src_mip_level, sampler_view``
|
|
|
|
Example: ``SVIEWINFO TEMP[0], TEMP[1].x, SVIEW[0]``
|
|
|
|
src_mip_level is an unsigned integer scalar. If it's out of range then
|
|
returns 0 for width, height and depth/array size but the total number of
|
|
mipmap is still returned correctly for the given sampler view. The returned
|
|
width, height and depth values are for the mipmap level selected by the
|
|
src_mip_level and are in the number of texels. For 1d texture array width
|
|
is in dst.x, array size is in dst.y and dst.z is 0. The number of mipmaps is
|
|
still in dst.w. In contrast to d3d10 resinfo, there's no way in the tgsi
|
|
instruction encoding to specify the return type (float/rcpfloat/uint), hence
|
|
always using uint. Also, unlike the SAMPLE instructions, the swizzle on src1
|
|
resinfo allowing swizzling dst values is ignored (due to the interaction
|
|
with rcpfloat modifier which requires some swizzle handling in the state
|
|
tracker anyway).
|
|
|
|
.. opcode:: SAMPLE_POS
|
|
|
|
Query the position of a sample in the given resource or render target
|
|
when per-sample fragment shading is in effect.
|
|
|
|
Syntax: ``SAMPLE_POS dst, source, sample_index``
|
|
|
|
dst receives float4 (x, y, undef, undef) indicated where the sample is
|
|
located. Sample locations are in the range [0, 1] where 0.5 is the center
|
|
of the fragment.
|
|
|
|
source is either a sampler view (to indicate a shader resource) or temp
|
|
register (to indicate the render target). The source register may have
|
|
an optional swizzle to apply to the returned result
|
|
|
|
sample_index is an integer scalar indicating which sample position is to
|
|
be queried.
|
|
|
|
If per-sample shading is not in effect or the source resource or render
|
|
target is not multisampled, the result is (0.5, 0.5, undef, undef).
|
|
|
|
NOTE: no driver has implemented this opcode yet (and no gallium frontend
|
|
emits it). This information is subject to change.
|
|
|
|
.. opcode:: SAMPLE_INFO
|
|
|
|
Query the number of samples in a multisampled resource or render target.
|
|
|
|
Syntax: ``SAMPLE_INFO dst, source``
|
|
|
|
dst receives int4 (n, 0, 0, 0) where n is the number of samples in a
|
|
resource or the render target.
|
|
|
|
source is either a sampler view (to indicate a shader resource) or temp
|
|
register (to indicate the render target). The source register may have
|
|
an optional swizzle to apply to the returned result
|
|
|
|
If per-sample shading is not in effect or the source resource or render
|
|
target is not multisampled, the result is (1, 0, 0, 0).
|
|
|
|
NOTE: no driver has implemented this opcode yet (and no gallium frontend
|
|
emits it). This information is subject to change.
|
|
|
|
.. opcode:: LOD - level of detail
|
|
|
|
Same syntax as the SAMPLE opcode but instead of performing an actual
|
|
texture lookup/filter, return the computed LOD information that the
|
|
texture pipe would use to access the texture. The Y component contains
|
|
the computed LOD lambda_prime. The X component contains the LOD that will
|
|
be accessed, based on min/max lod's and mipmap filters.
|
|
The Z and W components are set to 0.
|
|
|
|
Syntax: ``LOD dst, address, sampler_view, sampler``
|
|
|
|
|
|
.. _resourceopcodes:
|
|
|
|
Resource Access Opcodes
|
|
^^^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
For these opcodes, the resource can be a BUFFER, IMAGE, or MEMORY.
|
|
|
|
.. opcode:: LOAD - Fetch data from a shader buffer or image
|
|
|
|
Syntax: ``LOAD dst, resource, address``
|
|
|
|
Example: ``LOAD TEMP[0], BUFFER[0], TEMP[1]``
|
|
|
|
Using the provided integer address, LOAD fetches data
|
|
from the specified buffer or texture without any
|
|
filtering.
|
|
|
|
The 'address' is specified as a vector of unsigned
|
|
integers. If the 'address' is out of range the result
|
|
is unspecified.
|
|
|
|
Only the first mipmap level of a resource can be read
|
|
from using this instruction.
|
|
|
|
For 1D or 2D texture arrays, the array index is
|
|
provided as an unsigned integer in address.y or
|
|
address.z, respectively. address.yz are ignored for
|
|
buffers and 1D textures. address.z is ignored for 1D
|
|
texture arrays and 2D textures. address.w is always
|
|
ignored.
|
|
|
|
A swizzle suffix may be added to the resource argument
|
|
this will cause the resource data to be swizzled accordingly.
|
|
|
|
.. opcode:: STORE - Write data to a shader resource
|
|
|
|
Syntax: ``STORE resource, address, src``
|
|
|
|
Example: ``STORE BUFFER[0], TEMP[0], TEMP[1]``
|
|
|
|
Using the provided integer address, STORE writes data
|
|
to the specified buffer or texture.
|
|
|
|
The 'address' is specified as a vector of unsigned
|
|
integers. If the 'address' is out of range the result
|
|
is unspecified.
|
|
|
|
Only the first mipmap level of a resource can be
|
|
written to using this instruction.
|
|
|
|
For 1D or 2D texture arrays, the array index is
|
|
provided as an unsigned integer in address.y or
|
|
address.z, respectively. address.yz are ignored for
|
|
buffers and 1D textures. address.z is ignored for 1D
|
|
texture arrays and 2D textures. address.w is always
|
|
ignored.
|
|
|
|
.. opcode:: RESQ - Query information about a resource
|
|
|
|
Syntax: ``RESQ dst, resource``
|
|
|
|
Example: ``RESQ TEMP[0], BUFFER[0]``
|
|
|
|
Returns information about the buffer or image resource. For buffer
|
|
resources, the size (in bytes) is returned in the x component. For
|
|
image resources, .xyz will contain the width/height/layers of the
|
|
image, while .w will contain the number of samples for multi-sampled
|
|
images.
|
|
|
|
.. opcode:: FBFETCH - Load data from framebuffer
|
|
|
|
Syntax: ``FBFETCH dst, output``
|
|
|
|
Example: ``FBFETCH TEMP[0], OUT[0]``
|
|
|
|
This is only valid on ``COLOR`` semantic outputs. Returns the color
|
|
of the current position in the framebuffer from before this fragment
|
|
shader invocation. May return the same value from multiple calls for
|
|
a particular output within a single invocation. Note that result may
|
|
be undefined if a fragment is drawn multiple times without a blend
|
|
barrier in between.
|
|
|
|
|
|
.. _bindlessopcodes:
|
|
|
|
Bindless Opcodes
|
|
^^^^^^^^^^^^^^^^
|
|
|
|
These opcodes are for working with bindless sampler or image handles and
|
|
require PIPE_CAP_BINDLESS_TEXTURE.
|
|
|
|
.. opcode:: IMG2HND - Get a bindless handle for a image
|
|
|
|
Syntax: ``IMG2HND dst, image``
|
|
|
|
Example: ``IMG2HND TEMP[0], IMAGE[0]``
|
|
|
|
Sets 'dst' to a bindless handle for 'image'.
|
|
|
|
.. opcode:: SAMP2HND - Get a bindless handle for a sampler
|
|
|
|
Syntax: ``SAMP2HND dst, sampler``
|
|
|
|
Example: ``SAMP2HND TEMP[0], SAMP[0]``
|
|
|
|
Sets 'dst' to a bindless handle for 'sampler'.
|
|
|
|
|
|
.. _threadsyncopcodes:
|
|
|
|
Inter-thread synchronization opcodes
|
|
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
These opcodes are intended for communication between threads running
|
|
within the same compute grid. For now they're only valid in compute
|
|
programs.
|
|
|
|
.. opcode:: BARRIER - Thread group barrier
|
|
|
|
``BARRIER``
|
|
|
|
This opcode suspends the execution of the current thread until all
|
|
the remaining threads in the working group reach the same point of
|
|
the program. Results are unspecified if any of the remaining
|
|
threads terminates or never reaches an executed BARRIER instruction.
|
|
|
|
.. opcode:: MEMBAR - Memory barrier
|
|
|
|
``MEMBAR type``
|
|
|
|
This opcode waits for the completion of all memory accesses based on
|
|
the type passed in. The type is an immediate bitfield with the following
|
|
meaning:
|
|
|
|
Bit 0: Shader storage buffers
|
|
Bit 1: Atomic buffers
|
|
Bit 2: Images
|
|
Bit 3: Shared memory
|
|
Bit 4: Thread group
|
|
|
|
These may be passed in in any combination. An implementation is free to not
|
|
distinguish between these as it sees fit. However these map to all the
|
|
possibilities made available by GLSL.
|
|
|
|
.. _atomopcodes:
|
|
|
|
Atomic opcodes
|
|
^^^^^^^^^^^^^^
|
|
|
|
These opcodes provide atomic variants of some common arithmetic and
|
|
logical operations. In this context atomicity means that another
|
|
concurrent memory access operation that affects the same memory
|
|
location is guaranteed to be performed strictly before or after the
|
|
entire execution of the atomic operation. The resource may be a BUFFER,
|
|
IMAGE, HWATOMIC, or MEMORY. In the case of an image, the offset works
|
|
the same as for ``LOAD`` and ``STORE``, specified above. For atomic
|
|
counters, the offset is an immediate index to the base hw atomic
|
|
counter for this operation.
|
|
These atomic operations may only be used with 32-bit integer image formats.
|
|
|
|
.. opcode:: ATOMUADD - Atomic integer addition
|
|
|
|
Syntax: ``ATOMUADD dst, resource, offset, src``
|
|
|
|
Example: ``ATOMUADD TEMP[0], BUFFER[0], TEMP[1], TEMP[2]``
|
|
|
|
The following operation is performed atomically:
|
|
|
|
.. math::
|
|
|
|
dst_x = resource[offset]
|
|
|
|
resource[offset] = dst_x + src_x
|
|
|
|
|
|
.. opcode:: ATOMFADD - Atomic floating point addition
|
|
|
|
Syntax: ``ATOMFADD dst, resource, offset, src``
|
|
|
|
Example: ``ATOMFADD TEMP[0], BUFFER[0], TEMP[1], TEMP[2]``
|
|
|
|
The following operation is performed atomically:
|
|
|
|
.. math::
|
|
|
|
dst_x = resource[offset]
|
|
|
|
resource[offset] = dst_x + src_x
|
|
|
|
|
|
.. opcode:: ATOMXCHG - Atomic exchange
|
|
|
|
Syntax: ``ATOMXCHG dst, resource, offset, src``
|
|
|
|
Example: ``ATOMXCHG TEMP[0], BUFFER[0], TEMP[1], TEMP[2]``
|
|
|
|
The following operation is performed atomically:
|
|
|
|
.. math::
|
|
|
|
dst_x = resource[offset]
|
|
|
|
resource[offset] = src_x
|
|
|
|
|
|
.. opcode:: ATOMCAS - Atomic compare-and-exchange
|
|
|
|
Syntax: ``ATOMCAS dst, resource, offset, cmp, src``
|
|
|
|
Example: ``ATOMCAS TEMP[0], BUFFER[0], TEMP[1], TEMP[2], TEMP[3]``
|
|
|
|
The following operation is performed atomically:
|
|
|
|
.. math::
|
|
|
|
dst_x = resource[offset]
|
|
|
|
resource[offset] = (dst_x == cmp_x ? src_x : dst_x)
|
|
|
|
|
|
.. opcode:: ATOMAND - Atomic bitwise And
|
|
|
|
Syntax: ``ATOMAND dst, resource, offset, src``
|
|
|
|
Example: ``ATOMAND TEMP[0], BUFFER[0], TEMP[1], TEMP[2]``
|
|
|
|
The following operation is performed atomically:
|
|
|
|
.. math::
|
|
|
|
dst_x = resource[offset]
|
|
|
|
resource[offset] = dst_x \& src_x
|
|
|
|
|
|
.. opcode:: ATOMOR - Atomic bitwise Or
|
|
|
|
Syntax: ``ATOMOR dst, resource, offset, src``
|
|
|
|
Example: ``ATOMOR TEMP[0], BUFFER[0], TEMP[1], TEMP[2]``
|
|
|
|
The following operation is performed atomically:
|
|
|
|
.. math::
|
|
|
|
dst_x = resource[offset]
|
|
|
|
resource[offset] = dst_x | src_x
|
|
|
|
|
|
.. opcode:: ATOMXOR - Atomic bitwise Xor
|
|
|
|
Syntax: ``ATOMXOR dst, resource, offset, src``
|
|
|
|
Example: ``ATOMXOR TEMP[0], BUFFER[0], TEMP[1], TEMP[2]``
|
|
|
|
The following operation is performed atomically:
|
|
|
|
.. math::
|
|
|
|
dst_x = resource[offset]
|
|
|
|
resource[offset] = dst_x \oplus src_x
|
|
|
|
|
|
.. opcode:: ATOMUMIN - Atomic unsigned minimum
|
|
|
|
Syntax: ``ATOMUMIN dst, resource, offset, src``
|
|
|
|
Example: ``ATOMUMIN TEMP[0], BUFFER[0], TEMP[1], TEMP[2]``
|
|
|
|
The following operation is performed atomically:
|
|
|
|
.. math::
|
|
|
|
dst_x = resource[offset]
|
|
|
|
resource[offset] = (dst_x < src_x ? dst_x : src_x)
|
|
|
|
|
|
.. opcode:: ATOMUMAX - Atomic unsigned maximum
|
|
|
|
Syntax: ``ATOMUMAX dst, resource, offset, src``
|
|
|
|
Example: ``ATOMUMAX TEMP[0], BUFFER[0], TEMP[1], TEMP[2]``
|
|
|
|
The following operation is performed atomically:
|
|
|
|
.. math::
|
|
|
|
dst_x = resource[offset]
|
|
|
|
resource[offset] = (dst_x > src_x ? dst_x : src_x)
|
|
|
|
|
|
.. opcode:: ATOMIMIN - Atomic signed minimum
|
|
|
|
Syntax: ``ATOMIMIN dst, resource, offset, src``
|
|
|
|
Example: ``ATOMIMIN TEMP[0], BUFFER[0], TEMP[1], TEMP[2]``
|
|
|
|
The following operation is performed atomically:
|
|
|
|
.. math::
|
|
|
|
dst_x = resource[offset]
|
|
|
|
resource[offset] = (dst_x < src_x ? dst_x : src_x)
|
|
|
|
|
|
.. opcode:: ATOMIMAX - Atomic signed maximum
|
|
|
|
Syntax: ``ATOMIMAX dst, resource, offset, src``
|
|
|
|
Example: ``ATOMIMAX TEMP[0], BUFFER[0], TEMP[1], TEMP[2]``
|
|
|
|
The following operation is performed atomically:
|
|
|
|
.. math::
|
|
|
|
dst_x = resource[offset]
|
|
|
|
resource[offset] = (dst_x > src_x ? dst_x : src_x)
|
|
|
|
|
|
.. opcode:: ATOMINC_WRAP - Atomic increment + wrap around
|
|
|
|
Syntax: ``ATOMINC_WRAP dst, resource, offset, src``
|
|
|
|
Example: ``ATOMINC_WRAP TEMP[0], BUFFER[0], TEMP[1], TEMP[2]``
|
|
|
|
The following operation is performed atomically:
|
|
|
|
.. math::
|
|
|
|
dst_x = resource[offset] + 1
|
|
|
|
resource[offset] = dst_x <= src_x ? dst_x : 0
|
|
|
|
|
|
.. opcode:: ATOMDEC_WRAP - Atomic decrement + wrap around
|
|
|
|
Syntax: ``ATOMDEC_WRAP dst, resource, offset, src``
|
|
|
|
Example: ``ATOMDEC_WRAP TEMP[0], BUFFER[0], TEMP[1], TEMP[2]``
|
|
|
|
The following operation is performed atomically:
|
|
|
|
.. math::
|
|
|
|
dst_x = resource[offset]
|
|
|
|
resource[offset] = (dst_x > 0 && dst_x < src_x) ? dst_x - 1 : 0
|
|
|
|
|
|
.. _interlaneopcodes:
|
|
|
|
Inter-lane opcodes
|
|
^^^^^^^^^^^^^^^^^^
|
|
|
|
These opcodes reduce the given value across the shader invocations
|
|
running in the current SIMD group. Every thread in the subgroup will receive
|
|
the same result. The BALLOT operations accept a single-channel argument that
|
|
is treated as a boolean and produce a 64-bit value.
|
|
|
|
.. opcode:: VOTE_ANY - Value is set in any of the active invocations
|
|
|
|
Syntax: ``VOTE_ANY dst, value``
|
|
|
|
Example: ``VOTE_ANY TEMP[0].x, TEMP[1].x``
|
|
|
|
|
|
.. opcode:: VOTE_ALL - Value is set in all of the active invocations
|
|
|
|
Syntax: ``VOTE_ALL dst, value``
|
|
|
|
Example: ``VOTE_ALL TEMP[0].x, TEMP[1].x``
|
|
|
|
|
|
.. opcode:: VOTE_EQ - Value is the same in all of the active invocations
|
|
|
|
Syntax: ``VOTE_EQ dst, value``
|
|
|
|
Example: ``VOTE_EQ TEMP[0].x, TEMP[1].x``
|
|
|
|
|
|
.. opcode:: BALLOT - Lanemask of whether the value is set in each active
|
|
invocation
|
|
|
|
Syntax: ``BALLOT dst, value``
|
|
|
|
Example: ``BALLOT TEMP[0].xy, TEMP[1].x``
|
|
|
|
When the argument is a constant true, this produces a bitmask of active
|
|
invocations. In fragment shaders, this can include helper invocations
|
|
(invocations whose outputs and writes to memory are discarded, but which
|
|
are used to compute derivatives).
|
|
|
|
|
|
.. opcode:: READ_FIRST - Broadcast the value from the first active
|
|
invocation to all active lanes
|
|
|
|
Syntax: ``READ_FIRST dst, value``
|
|
|
|
Example: ``READ_FIRST TEMP[0], TEMP[1]``
|
|
|
|
|
|
.. opcode:: READ_INVOC - Retrieve the value from the given invocation
|
|
(need not be uniform)
|
|
|
|
Syntax: ``READ_INVOC dst, value, invocation``
|
|
|
|
Example: ``READ_INVOC TEMP[0].xy, TEMP[1].xy, TEMP[2].x``
|
|
|
|
invocation.x controls the invocation number to read from for all channels.
|
|
The invocation number must be the same across all active invocations in a
|
|
sub-group; otherwise, the results are undefined.
|
|
|
|
|
|
Explanation of symbols used
|
|
------------------------------
|
|
|
|
|
|
Functions
|
|
^^^^^^^^^^^^^^
|
|
|
|
|
|
:math:`|x|` Absolute value of `x`.
|
|
|
|
:math:`\lceil x \rceil` Ceiling of `x`.
|
|
|
|
clamp(x,y,z) Clamp x between y and z.
|
|
(x < y) ? y : (x > z) ? z : x
|
|
|
|
:math:`\lfloor x\rfloor` Floor of `x`.
|
|
|
|
:math:`\log_2{x}` Logarithm of `x`, base 2.
|
|
|
|
max(x,y) Maximum of x and y.
|
|
(x > y) ? x : y
|
|
|
|
min(x,y) Minimum of x and y.
|
|
(x < y) ? x : y
|
|
|
|
partialx(x) Derivative of x relative to fragment's X.
|
|
|
|
partialy(x) Derivative of x relative to fragment's Y.
|
|
|
|
pop() Pop from stack.
|
|
|
|
:math:`x^y` `x` to the power `y`.
|
|
|
|
push(x) Push x on stack.
|
|
|
|
round(x) Round x.
|
|
|
|
trunc(x) Truncate x, i.e. drop the fraction bits.
|
|
|
|
|
|
Keywords
|
|
^^^^^^^^^^^^^
|
|
|
|
|
|
discard Discard fragment.
|
|
|
|
pc Program counter.
|
|
|
|
target Label of target instruction.
|
|
|
|
|
|
Other tokens
|
|
---------------
|
|
|
|
|
|
Declaration
|
|
^^^^^^^^^^^
|
|
|
|
|
|
Declares a register that is will be referenced as an operand in Instruction
|
|
tokens.
|
|
|
|
File field contains register file that is being declared and is one
|
|
of TGSI_FILE.
|
|
|
|
UsageMask field specifies which of the register components can be accessed
|
|
and is one of TGSI_WRITEMASK.
|
|
|
|
The Local flag specifies that a given value isn't intended for
|
|
subroutine parameter passing and, as a result, the implementation
|
|
isn't required to give any guarantees of it being preserved across
|
|
subroutine boundaries. As it's merely a compiler hint, the
|
|
implementation is free to ignore it.
|
|
|
|
If Dimension flag is set to 1, a Declaration Dimension token follows.
|
|
|
|
If Semantic flag is set to 1, a Declaration Semantic token follows.
|
|
|
|
If Interpolate flag is set to 1, a Declaration Interpolate token follows.
|
|
|
|
If file is TGSI_FILE_RESOURCE, a Declaration Resource token follows.
|
|
|
|
If Array flag is set to 1, a Declaration Array token follows.
|
|
|
|
Array Declaration
|
|
^^^^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
Declarations can optional have an ArrayID attribute which can be referred by
|
|
indirect addressing operands. An ArrayID of zero is reserved and treated as
|
|
if no ArrayID is specified.
|
|
|
|
If an indirect addressing operand refers to a specific declaration by using
|
|
an ArrayID only the registers in this declaration are guaranteed to be
|
|
accessed, accessing any register outside this declaration results in undefined
|
|
behavior. Note that for compatibility the effective index is zero-based and
|
|
not relative to the specified declaration
|
|
|
|
If no ArrayID is specified with an indirect addressing operand the whole
|
|
register file might be accessed by this operand. This is strongly discouraged
|
|
and will prevent packing of scalar/vec2 arrays and effective alias analysis.
|
|
This is only legal for TEMP and CONST register files.
|
|
|
|
Declaration Semantic
|
|
^^^^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
Vertex and fragment shader input and output registers may be labeled
|
|
with semantic information consisting of a name and index.
|
|
|
|
Follows Declaration token if Semantic bit is set.
|
|
|
|
Since its purpose is to link a shader with other stages of the pipeline,
|
|
it is valid to follow only those Declaration tokens that declare a register
|
|
either in INPUT or OUTPUT file.
|
|
|
|
SemanticName field contains the semantic name of the register being declared.
|
|
There is no default value.
|
|
|
|
SemanticIndex is an optional subscript that can be used to distinguish
|
|
different register declarations with the same semantic name. The default value
|
|
is 0.
|
|
|
|
The meanings of the individual semantic names are explained in the following
|
|
sections.
|
|
|
|
TGSI_SEMANTIC_POSITION
|
|
""""""""""""""""""""""
|
|
|
|
For vertex shaders, TGSI_SEMANTIC_POSITION indicates the vertex shader
|
|
output register which contains the homogeneous vertex position in the clip
|
|
space coordinate system. After clipping, the X, Y and Z components of the
|
|
vertex will be divided by the W value to get normalized device coordinates.
|
|
|
|
For fragment shaders, TGSI_SEMANTIC_POSITION is used to indicate that
|
|
fragment shader input (or system value, depending on which one is
|
|
supported by the driver) contains the fragment's window position. The X
|
|
component starts at zero and always increases from left to right.
|
|
The Y component starts at zero and always increases but Y=0 may either
|
|
indicate the top of the window or the bottom depending on the fragment
|
|
coordinate origin convention (see TGSI_PROPERTY_FS_COORD_ORIGIN).
|
|
The Z coordinate ranges from 0 to 1 to represent depth from the front
|
|
to the back of the Z buffer. The W component contains the interpolated
|
|
reciprocal of the vertex position W component (corresponding to gl_Fragcoord,
|
|
but unlike d3d10 which interpolates the same 1/w but then gives back
|
|
the reciprocal of the interpolated value).
|
|
|
|
Fragment shaders may also declare an output register with
|
|
TGSI_SEMANTIC_POSITION. Only the Z component is writable. This allows
|
|
the fragment shader to change the fragment's Z position.
|
|
|
|
|
|
|
|
TGSI_SEMANTIC_COLOR
|
|
"""""""""""""""""""
|
|
|
|
For vertex shader outputs or fragment shader inputs/outputs, this
|
|
label indicates that the register contains an R,G,B,A color.
|
|
|
|
Several shader inputs/outputs may contain colors so the semantic index
|
|
is used to distinguish them. For example, color[0] may be the diffuse
|
|
color while color[1] may be the specular color.
|
|
|
|
This label is needed so that the flat/smooth shading can be applied
|
|
to the right interpolants during rasterization.
|
|
|
|
|
|
|
|
TGSI_SEMANTIC_BCOLOR
|
|
""""""""""""""""""""
|
|
|
|
Back-facing colors are only used for back-facing polygons, and are only valid
|
|
in vertex shader outputs. After rasterization, all polygons are front-facing
|
|
and COLOR and BCOLOR end up occupying the same slots in the fragment shader,
|
|
so all BCOLORs effectively become regular COLORs in the fragment shader.
|
|
|
|
|
|
TGSI_SEMANTIC_FOG
|
|
"""""""""""""""""
|
|
|
|
Vertex shader inputs and outputs and fragment shader inputs may be
|
|
labeled with TGSI_SEMANTIC_FOG to indicate that the register contains
|
|
a fog coordinate. Typically, the fragment shader will use the fog coordinate
|
|
to compute a fog blend factor which is used to blend the normal fragment color
|
|
with a constant fog color. But fog coord really is just an ordinary vec4
|
|
register like regular semantics.
|
|
|
|
|
|
TGSI_SEMANTIC_PSIZE
|
|
"""""""""""""""""""
|
|
|
|
Vertex shader input and output registers may be labeled with
|
|
TGIS_SEMANTIC_PSIZE to indicate that the register contains a point size
|
|
in the form (S, 0, 0, 1). The point size controls the width or diameter
|
|
of points for rasterization. This label cannot be used in fragment
|
|
shaders.
|
|
|
|
When using this semantic, be sure to set the appropriate state in the
|
|
:ref:`rasterizer` first.
|
|
|
|
|
|
TGSI_SEMANTIC_TEXCOORD
|
|
""""""""""""""""""""""
|
|
|
|
Only available if PIPE_CAP_TGSI_TEXCOORD is exposed !
|
|
|
|
Vertex shader outputs and fragment shader inputs may be labeled with
|
|
this semantic to make them replaceable by sprite coordinates via the
|
|
sprite_coord_enable state in the :ref:`rasterizer`.
|
|
The semantic index permitted with this semantic is limited to <= 7.
|
|
|
|
If the driver does not support TEXCOORD, sprite coordinate replacement
|
|
applies to inputs with the GENERIC semantic instead.
|
|
|
|
The intended use case for this semantic is gl_TexCoord.
|
|
|
|
|
|
TGSI_SEMANTIC_PCOORD
|
|
""""""""""""""""""""
|
|
|
|
Only available if PIPE_CAP_TGSI_TEXCOORD is exposed !
|
|
|
|
Fragment shader inputs may be labeled with TGSI_SEMANTIC_PCOORD to indicate
|
|
that the register contains sprite coordinates in the form (x, y, 0, 1), if
|
|
the current primitive is a point and point sprites are enabled. Otherwise,
|
|
the contents of the register are undefined.
|
|
|
|
The intended use case for this semantic is gl_PointCoord.
|
|
|
|
|
|
TGSI_SEMANTIC_GENERIC
|
|
"""""""""""""""""""""
|
|
|
|
All vertex/fragment shader inputs/outputs not labeled with any other
|
|
semantic label can be considered to be generic attributes. Typical
|
|
uses of generic inputs/outputs are texcoords and user-defined values.
|
|
|
|
|
|
TGSI_SEMANTIC_NORMAL
|
|
""""""""""""""""""""
|
|
|
|
Indicates that a vertex shader input is a normal vector. This is
|
|
typically only used for legacy graphics APIs.
|
|
|
|
|
|
TGSI_SEMANTIC_FACE
|
|
""""""""""""""""""
|
|
|
|
This label applies to fragment shader inputs (or system values,
|
|
depending on which one is supported by the driver) and indicates that
|
|
the register contains front/back-face information.
|
|
|
|
If it is an input, it will be a floating-point vector in the form (F, 0, 0, 1),
|
|
where F will be positive when the fragment belongs to a front-facing polygon,
|
|
and negative when the fragment belongs to a back-facing polygon.
|
|
|
|
If it is a system value, it will be an integer vector in the form (F, 0, 0, 1),
|
|
where F is 0xffffffff when the fragment belongs to a front-facing polygon and
|
|
0 when the fragment belongs to a back-facing polygon.
|
|
|
|
|
|
TGSI_SEMANTIC_EDGEFLAG
|
|
""""""""""""""""""""""
|
|
|
|
For vertex shaders, this sematic label indicates that an input or
|
|
output is a boolean edge flag. The register layout is [F, x, x, x]
|
|
where F is 0.0 or 1.0 and x = don't care. Normally, the vertex shader
|
|
simply copies the edge flag input to the edgeflag output.
|
|
|
|
Edge flags are used to control which lines or points are actually
|
|
drawn when the polygon mode converts triangles/quads/polygons into
|
|
points or lines.
|
|
|
|
|
|
TGSI_SEMANTIC_STENCIL
|
|
"""""""""""""""""""""
|
|
|
|
For fragment shaders, this semantic label indicates that an output
|
|
is a writable stencil reference value. Only the Y component is writable.
|
|
This allows the fragment shader to change the fragments stencilref value.
|
|
|
|
|
|
TGSI_SEMANTIC_VIEWPORT_INDEX
|
|
""""""""""""""""""""""""""""
|
|
|
|
For geometry shaders, this semantic label indicates that an output
|
|
contains the index of the viewport (and scissor) to use.
|
|
This is an integer value, and only the X component is used.
|
|
|
|
If PIPE_CAP_TGSI_VS_LAYER_VIEWPORT or PIPE_CAP_TGSI_TES_LAYER_VIEWPORT is
|
|
supported, then this semantic label can also be used in vertex or
|
|
tessellation evaluation shaders, respectively. Only the value written in the
|
|
last vertex processing stage is used.
|
|
|
|
|
|
TGSI_SEMANTIC_LAYER
|
|
"""""""""""""""""""
|
|
|
|
For geometry shaders, this semantic label indicates that an output
|
|
contains the layer value to use for the color and depth/stencil surfaces.
|
|
This is an integer value, and only the X component is used.
|
|
(Also known as rendertarget array index.)
|
|
|
|
If PIPE_CAP_TGSI_VS_LAYER_VIEWPORT or PIPE_CAP_TGSI_TES_LAYER_VIEWPORT is
|
|
supported, then this semantic label can also be used in vertex or
|
|
tessellation evaluation shaders, respectively. Only the value written in the
|
|
last vertex processing stage is used.
|
|
|
|
|
|
TGSI_SEMANTIC_CLIPDIST
|
|
""""""""""""""""""""""
|
|
|
|
Note this covers clipping and culling distances.
|
|
|
|
When components of vertex elements are identified this way, these
|
|
values are each assumed to be a float32 signed distance to a plane.
|
|
|
|
For clip distances:
|
|
Primitive setup only invokes rasterization on pixels for which
|
|
the interpolated plane distances are >= 0.
|
|
|
|
For cull distances:
|
|
Primitives will be completely discarded if the plane distance
|
|
for all of the vertices in the primitive are < 0.
|
|
If a vertex has a cull distance of NaN, that vertex counts as "out"
|
|
(as if its < 0);
|
|
|
|
Multiple clip/cull planes can be implemented simultaneously, by
|
|
annotating multiple components of one or more vertex elements with
|
|
the above specified semantic.
|
|
The limits on both clip and cull distances are bound
|
|
by the PIPE_MAX_CLIP_OR_CULL_DISTANCE_COUNT define which defines
|
|
the maximum number of components that can be used to hold the
|
|
distances and by the PIPE_MAX_CLIP_OR_CULL_DISTANCE_ELEMENT_COUNT
|
|
which specifies the maximum number of registers which can be
|
|
annotated with those semantics.
|
|
The properties NUM_CLIPDIST_ENABLED and NUM_CULLDIST_ENABLED
|
|
are used to divide up the 2 x vec4 space between clipping and culling.
|
|
|
|
TGSI_SEMANTIC_SAMPLEID
|
|
""""""""""""""""""""""
|
|
|
|
For fragment shaders, this semantic label indicates that a system value
|
|
contains the current sample id (i.e. gl_SampleID) as an unsigned int.
|
|
Only the X component is used. If per-sample shading is not enabled,
|
|
the result is (0, undef, undef, undef).
|
|
|
|
Note that if the fragment shader uses this system value, the fragment
|
|
shader is automatically executed at per sample frequency.
|
|
|
|
TGSI_SEMANTIC_SAMPLEPOS
|
|
"""""""""""""""""""""""
|
|
|
|
For fragment shaders, this semantic label indicates that a system
|
|
value contains the current sample's position as float4(x, y, undef, undef)
|
|
in the render target (i.e. gl_SamplePosition) when per-fragment shading
|
|
is in effect. Position values are in the range [0, 1] where 0.5 is
|
|
the center of the fragment.
|
|
|
|
Note that if the fragment shader uses this system value, the fragment
|
|
shader is automatically executed at per sample frequency.
|
|
|
|
TGSI_SEMANTIC_SAMPLEMASK
|
|
""""""""""""""""""""""""
|
|
|
|
For fragment shaders, this semantic label can be applied to either a
|
|
shader system value input or output.
|
|
|
|
For a system value, the sample mask indicates the set of samples covered by
|
|
the current primitive. If MSAA is not enabled, the value is (1, 0, 0, 0).
|
|
|
|
For an output, the sample mask is used to disable further sample processing.
|
|
|
|
For both, the register type is uint[4] but only the X component is used
|
|
(i.e. gl_SampleMask[0]). Each bit corresponds to one sample position (up
|
|
to 32x MSAA is supported).
|
|
|
|
TGSI_SEMANTIC_INVOCATIONID
|
|
""""""""""""""""""""""""""
|
|
|
|
For geometry shaders, this semantic label indicates that a system value
|
|
contains the current invocation id (i.e. gl_InvocationID).
|
|
This is an integer value, and only the X component is used.
|
|
|
|
TGSI_SEMANTIC_INSTANCEID
|
|
""""""""""""""""""""""""
|
|
|
|
For vertex shaders, this semantic label indicates that a system value contains
|
|
the current instance id (i.e. gl_InstanceID). It does not include the base
|
|
instance. This is an integer value, and only the X component is used.
|
|
|
|
TGSI_SEMANTIC_VERTEXID
|
|
""""""""""""""""""""""
|
|
|
|
For vertex shaders, this semantic label indicates that a system value contains
|
|
the current vertex id (i.e. gl_VertexID). It does (unlike in d3d10) include the
|
|
base vertex. This is an integer value, and only the X component is used.
|
|
|
|
TGSI_SEMANTIC_VERTEXID_NOBASE
|
|
"""""""""""""""""""""""""""""""
|
|
|
|
For vertex shaders, this semantic label indicates that a system value contains
|
|
the current vertex id without including the base vertex (this corresponds to
|
|
d3d10 vertex id, so TGSI_SEMANTIC_VERTEXID_NOBASE + TGSI_SEMANTIC_BASEVERTEX
|
|
== TGSI_SEMANTIC_VERTEXID). This is an integer value, and only the X component
|
|
is used.
|
|
|
|
TGSI_SEMANTIC_BASEVERTEX
|
|
""""""""""""""""""""""""
|
|
|
|
For vertex shaders, this semantic label indicates that a system value contains
|
|
the base vertex (i.e. gl_BaseVertex). Note that for non-indexed draw calls,
|
|
this contains the first (or start) value instead.
|
|
This is an integer value, and only the X component is used.
|
|
|
|
TGSI_SEMANTIC_PRIMID
|
|
""""""""""""""""""""
|
|
|
|
For geometry and fragment shaders, this semantic label indicates the value
|
|
contains the primitive id (i.e. gl_PrimitiveID). This is an integer value,
|
|
and only the X component is used.
|
|
FIXME: This right now can be either a ordinary input or a system value...
|
|
|
|
|
|
TGSI_SEMANTIC_PATCH
|
|
"""""""""""""""""""
|
|
|
|
For tessellation evaluation/control shaders, this semantic label indicates a
|
|
generic per-patch attribute. Such semantics will not implicitly be per-vertex
|
|
arrays.
|
|
|
|
TGSI_SEMANTIC_TESSCOORD
|
|
"""""""""""""""""""""""
|
|
|
|
For tessellation evaluation shaders, this semantic label indicates the
|
|
coordinates of the vertex being processed. This is available in XYZ; W is
|
|
undefined.
|
|
|
|
TGSI_SEMANTIC_TESSOUTER
|
|
"""""""""""""""""""""""
|
|
|
|
For tessellation evaluation/control shaders, this semantic label indicates the
|
|
outer tessellation levels of the patch. Isoline tessellation will only have XY
|
|
defined, triangle will have XYZ and quads will have XYZW defined. This
|
|
corresponds to gl_TessLevelOuter.
|
|
|
|
TGSI_SEMANTIC_TESSINNER
|
|
"""""""""""""""""""""""
|
|
|
|
For tessellation evaluation/control shaders, this semantic label indicates the
|
|
inner tessellation levels of the patch. The X value is only defined for
|
|
triangle tessellation, while quads will have XY defined. This is entirely
|
|
undefined for isoline tessellation.
|
|
|
|
TGSI_SEMANTIC_VERTICESIN
|
|
""""""""""""""""""""""""
|
|
|
|
For tessellation evaluation/control shaders, this semantic label indicates the
|
|
number of vertices provided in the input patch. Only the X value is defined.
|
|
|
|
TGSI_SEMANTIC_HELPER_INVOCATION
|
|
"""""""""""""""""""""""""""""""
|
|
|
|
For fragment shaders, this semantic indicates whether the current
|
|
invocation is covered or not. Helper invocations are created in order
|
|
to properly compute derivatives, however it may be desirable to skip
|
|
some of the logic in those cases. See ``gl_HelperInvocation`` documentation.
|
|
|
|
TGSI_SEMANTIC_BASEINSTANCE
|
|
""""""""""""""""""""""""""
|
|
|
|
For vertex shaders, the base instance argument supplied for this
|
|
draw. This is an integer value, and only the X component is used.
|
|
|
|
TGSI_SEMANTIC_DRAWID
|
|
""""""""""""""""""""
|
|
|
|
For vertex shaders, the zero-based index of the current draw in a
|
|
``glMultiDraw*`` invocation. This is an integer value, and only the X
|
|
component is used.
|
|
|
|
|
|
TGSI_SEMANTIC_WORK_DIM
|
|
""""""""""""""""""""""
|
|
|
|
For compute shaders started via OpenCL this retrieves the work_dim
|
|
parameter to the clEnqueueNDRangeKernel call with which the shader
|
|
was started.
|
|
|
|
|
|
TGSI_SEMANTIC_GRID_SIZE
|
|
"""""""""""""""""""""""
|
|
|
|
For compute shaders, this semantic indicates the maximum (x, y, z) dimensions
|
|
of a grid of thread blocks.
|
|
|
|
|
|
TGSI_SEMANTIC_BLOCK_ID
|
|
""""""""""""""""""""""
|
|
|
|
For compute shaders, this semantic indicates the (x, y, z) coordinates of the
|
|
current block inside of the grid.
|
|
|
|
|
|
TGSI_SEMANTIC_BLOCK_SIZE
|
|
""""""""""""""""""""""""
|
|
|
|
For compute shaders, this semantic indicates the maximum (x, y, z) dimensions
|
|
of a block in threads.
|
|
|
|
|
|
TGSI_SEMANTIC_THREAD_ID
|
|
"""""""""""""""""""""""
|
|
|
|
For compute shaders, this semantic indicates the (x, y, z) coordinates of the
|
|
current thread inside of the block.
|
|
|
|
|
|
TGSI_SEMANTIC_SUBGROUP_SIZE
|
|
"""""""""""""""""""""""""""
|
|
|
|
This semantic indicates the subgroup size for the current invocation. This is
|
|
an integer of at most 64, as it indicates the width of lanemasks. It does not
|
|
depend on the number of invocations that are active.
|
|
|
|
|
|
TGSI_SEMANTIC_SUBGROUP_INVOCATION
|
|
"""""""""""""""""""""""""""""""""
|
|
|
|
The index of the current invocation within its subgroup.
|
|
|
|
|
|
TGSI_SEMANTIC_SUBGROUP_EQ_MASK
|
|
""""""""""""""""""""""""""""""
|
|
|
|
A bit mask of ``bit index == TGSI_SEMANTIC_SUBGROUP_INVOCATION``, i.e.
|
|
``1 << subgroup_invocation`` in arbitrary precision arithmetic.
|
|
|
|
|
|
TGSI_SEMANTIC_SUBGROUP_GE_MASK
|
|
""""""""""""""""""""""""""""""
|
|
|
|
A bit mask of ``bit index >= TGSI_SEMANTIC_SUBGROUP_INVOCATION``, i.e.
|
|
``((1 << (subgroup_size - subgroup_invocation)) - 1) << subgroup_invocation``
|
|
in arbitrary precision arithmetic.
|
|
|
|
|
|
TGSI_SEMANTIC_SUBGROUP_GT_MASK
|
|
""""""""""""""""""""""""""""""
|
|
|
|
A bit mask of ``bit index > TGSI_SEMANTIC_SUBGROUP_INVOCATION``, i.e.
|
|
``((1 << (subgroup_size - subgroup_invocation - 1)) - 1) << (subgroup_invocation + 1)``
|
|
in arbitrary precision arithmetic.
|
|
|
|
|
|
TGSI_SEMANTIC_SUBGROUP_LE_MASK
|
|
""""""""""""""""""""""""""""""
|
|
|
|
A bit mask of ``bit index <= TGSI_SEMANTIC_SUBGROUP_INVOCATION``, i.e.
|
|
``(1 << (subgroup_invocation + 1)) - 1`` in arbitrary precision arithmetic.
|
|
|
|
|
|
TGSI_SEMANTIC_SUBGROUP_LT_MASK
|
|
""""""""""""""""""""""""""""""
|
|
|
|
A bit mask of ``bit index < TGSI_SEMANTIC_SUBGROUP_INVOCATION``, i.e.
|
|
``(1 << subgroup_invocation) - 1`` in arbitrary precision arithmetic.
|
|
|
|
|
|
TGSI_SEMANTIC_VIEWPORT_MASK
|
|
"""""""""""""""""""""""""""
|
|
|
|
A bit mask of viewports to broadcast the current primitive to. See
|
|
GL_NV_viewport_array2 for more details.
|
|
|
|
|
|
TGSI_SEMANTIC_TESS_DEFAULT_OUTER_LEVEL
|
|
""""""""""""""""""""""""""""""""""""""
|
|
|
|
A system value equal to the default_outer_level array set via set_tess_level.
|
|
|
|
|
|
TGSI_SEMANTIC_TESS_DEFAULT_INNER_LEVEL
|
|
""""""""""""""""""""""""""""""""""""""
|
|
|
|
A system value equal to the default_inner_level array set via set_tess_level.
|
|
|
|
|
|
Declaration Interpolate
|
|
^^^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
This token is only valid for fragment shader INPUT declarations.
|
|
|
|
The Interpolate field specifes the way input is being interpolated by
|
|
the rasteriser and is one of TGSI_INTERPOLATE_*.
|
|
|
|
The Location field specifies the location inside the pixel that the
|
|
interpolation should be done at, one of ``TGSI_INTERPOLATE_LOC_*``. Note that
|
|
when per-sample shading is enabled, the implementation may choose to
|
|
interpolate at the sample irrespective of the Location field.
|
|
|
|
|
|
Declaration Sampler View
|
|
^^^^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
Follows Declaration token if file is TGSI_FILE_SAMPLER_VIEW.
|
|
|
|
DCL SVIEW[#], resource, type(s)
|
|
|
|
Declares a shader input sampler view and assigns it to a SVIEW[#]
|
|
register.
|
|
|
|
resource can be one of BUFFER, 1D, 2D, 3D, 1DArray and 2DArray.
|
|
|
|
type must be 1 or 4 entries (if specifying on a per-component
|
|
level) out of UNORM, SNORM, SINT, UINT and FLOAT.
|
|
|
|
For TEX\* style texture sample opcodes (as opposed to SAMPLE\* opcodes
|
|
which take an explicit SVIEW[#] source register), there may be optionally
|
|
SVIEW[#] declarations. In this case, the SVIEW index is implied by the
|
|
SAMP index, and there must be a corresponding SVIEW[#] declaration for
|
|
each SAMP[#] declaration. Drivers are free to ignore this if they wish.
|
|
But note in particular that some drivers need to know the sampler type
|
|
(float/int/unsigned) in order to generate the correct code, so cases
|
|
where integer textures are sampled, SVIEW[#] declarations should be
|
|
used.
|
|
|
|
NOTE: It is NOT legal to mix SAMPLE\* style opcodes and TEX\* opcodes
|
|
in the same shader.
|
|
|
|
Declaration Resource
|
|
^^^^^^^^^^^^^^^^^^^^
|
|
|
|
Follows Declaration token if file is TGSI_FILE_RESOURCE.
|
|
|
|
DCL RES[#], resource [, WR] [, RAW]
|
|
|
|
Declares a shader input resource and assigns it to a RES[#]
|
|
register.
|
|
|
|
resource can be one of BUFFER, 1D, 2D, 3D, CUBE, 1DArray and
|
|
2DArray.
|
|
|
|
If the RAW keyword is not specified, the texture data will be
|
|
subject to conversion, swizzling and scaling as required to yield
|
|
the specified data type from the physical data format of the bound
|
|
resource.
|
|
|
|
If the RAW keyword is specified, no channel conversion will be
|
|
performed: the values read for each of the channels (X,Y,Z,W) will
|
|
correspond to consecutive words in the same order and format
|
|
they're found in memory. No element-to-address conversion will be
|
|
performed either: the value of the provided X coordinate will be
|
|
interpreted in byte units instead of texel units. The result of
|
|
accessing a misaligned address is undefined.
|
|
|
|
Usage of the STORE opcode is only allowed if the WR (writable) flag
|
|
is set.
|
|
|
|
Hardware Atomic Register File
|
|
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
Hardware atomics are declared as a 2D array with an optional array id.
|
|
|
|
The first member of the dimension is the buffer resource the atomic
|
|
is located in.
|
|
The second member is a range into the buffer resource, either for
|
|
one or multiple counters. If this is an array, the declaration will have
|
|
an unique array id.
|
|
|
|
Each counter is 4 bytes in size, and index and ranges are in counters not bytes.
|
|
DCL HWATOMIC[0][0]
|
|
DCL HWATOMIC[0][1]
|
|
|
|
This declares two atomics, one at the start of the buffer and one in the
|
|
second 4 bytes.
|
|
|
|
DCL HWATOMIC[0][0]
|
|
DCL HWATOMIC[1][0]
|
|
DCL HWATOMIC[1][1..3], ARRAY(1)
|
|
|
|
This declares 5 atomics, one in buffer 0 at 0,
|
|
one in buffer 1 at 0, and an array of 3 atomics in
|
|
the buffer 1, starting at 1.
|
|
|
|
Properties
|
|
^^^^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
Properties are general directives that apply to the whole TGSI program.
|
|
|
|
FS_COORD_ORIGIN
|
|
"""""""""""""""
|
|
|
|
Specifies the fragment shader TGSI_SEMANTIC_POSITION coordinate origin.
|
|
The default value is UPPER_LEFT.
|
|
|
|
If UPPER_LEFT, the position will be (0,0) at the upper left corner and
|
|
increase downward and rightward.
|
|
If LOWER_LEFT, the position will be (0,0) at the lower left corner and
|
|
increase upward and rightward.
|
|
|
|
OpenGL defaults to LOWER_LEFT, and is configurable with the
|
|
GL_ARB_fragment_coord_conventions extension.
|
|
|
|
DirectX 9/10 use UPPER_LEFT.
|
|
|
|
FS_COORD_PIXEL_CENTER
|
|
"""""""""""""""""""""
|
|
|
|
Specifies the fragment shader TGSI_SEMANTIC_POSITION pixel center convention.
|
|
The default value is HALF_INTEGER.
|
|
|
|
If HALF_INTEGER, the fractionary part of the position will be 0.5
|
|
If INTEGER, the fractionary part of the position will be 0.0
|
|
|
|
Note that this does not affect the set of fragments generated by
|
|
rasterization, which is instead controlled by half_pixel_center in the
|
|
rasterizer.
|
|
|
|
OpenGL defaults to HALF_INTEGER, and is configurable with the
|
|
GL_ARB_fragment_coord_conventions extension.
|
|
|
|
DirectX 9 uses INTEGER.
|
|
DirectX 10 uses HALF_INTEGER.
|
|
|
|
FS_COLOR0_WRITES_ALL_CBUFS
|
|
""""""""""""""""""""""""""
|
|
Specifies that writes to the fragment shader color 0 are replicated to all
|
|
bound cbufs. This facilitates OpenGL's fragColor output vs fragData[0] where
|
|
fragData is directed to a single color buffer, but fragColor is broadcast.
|
|
|
|
VS_PROHIBIT_UCPS
|
|
""""""""""""""""""""""""""
|
|
If this property is set on the program bound to the shader stage before the
|
|
fragment shader, user clip planes should have no effect (be disabled) even if
|
|
that shader does not write to any clip distance outputs and the rasterizer's
|
|
clip_plane_enable is non-zero.
|
|
This property is only supported by drivers that also support shader clip
|
|
distance outputs.
|
|
This is useful for APIs that don't have UCPs and where clip distances written
|
|
by a shader cannot be disabled.
|
|
|
|
GS_INVOCATIONS
|
|
""""""""""""""
|
|
|
|
Specifies the number of times a geometry shader should be executed for each
|
|
input primitive. Each invocation will have a different
|
|
TGSI_SEMANTIC_INVOCATIONID system value set. If not specified, assumed to
|
|
be 1.
|
|
|
|
VS_WINDOW_SPACE_POSITION
|
|
""""""""""""""""""""""""""
|
|
If this property is set on the vertex shader, the TGSI_SEMANTIC_POSITION output
|
|
is assumed to contain window space coordinates.
|
|
Division of X,Y,Z by W and the viewport transformation are disabled, and 1/W is
|
|
directly taken from the 4-th component of the shader output.
|
|
Naturally, clipping is not performed on window coordinates either.
|
|
The effect of this property is undefined if a geometry or tessellation shader
|
|
are in use.
|
|
|
|
TCS_VERTICES_OUT
|
|
""""""""""""""""
|
|
|
|
The number of vertices written by the tessellation control shader. This
|
|
effectively defines the patch input size of the tessellation evaluation shader
|
|
as well.
|
|
|
|
TES_PRIM_MODE
|
|
"""""""""""""
|
|
|
|
This sets the tessellation primitive mode, one of ``PIPE_PRIM_TRIANGLES``,
|
|
``PIPE_PRIM_QUADS``, or ``PIPE_PRIM_LINES``. (Unlike in GL, there is no
|
|
separate isolines settings, the regular lines is assumed to mean isolines.)
|
|
|
|
TES_SPACING
|
|
"""""""""""
|
|
|
|
This sets the spacing mode of the tessellation generator, one of
|
|
``PIPE_TESS_SPACING_*``.
|
|
|
|
TES_VERTEX_ORDER_CW
|
|
"""""""""""""""""""
|
|
|
|
This sets the vertex order to be clockwise if the value is 1, or
|
|
counter-clockwise if set to 0.
|
|
|
|
TES_POINT_MODE
|
|
""""""""""""""
|
|
|
|
If set to a non-zero value, this turns on point mode for the tessellator,
|
|
which means that points will be generated instead of primitives.
|
|
|
|
NUM_CLIPDIST_ENABLED
|
|
""""""""""""""""""""
|
|
|
|
How many clip distance scalar outputs are enabled.
|
|
|
|
NUM_CULLDIST_ENABLED
|
|
""""""""""""""""""""
|
|
|
|
How many cull distance scalar outputs are enabled.
|
|
|
|
FS_EARLY_DEPTH_STENCIL
|
|
""""""""""""""""""""""
|
|
|
|
Whether depth test, stencil test, and occlusion query should run before
|
|
the fragment shader (regardless of fragment shader side effects). Corresponds
|
|
to GLSL early_fragment_tests.
|
|
|
|
NEXT_SHADER
|
|
"""""""""""
|
|
|
|
Which shader stage will MOST LIKELY follow after this shader when the shader
|
|
is bound. This is only a hint to the driver and doesn't have to be precise.
|
|
Only set for VS and TES.
|
|
|
|
CS_FIXED_BLOCK_WIDTH / HEIGHT / DEPTH
|
|
"""""""""""""""""""""""""""""""""""""
|
|
|
|
Threads per block in each dimension, if known at compile time. If the block size
|
|
is known all three should be at least 1. If it is unknown they should all be set
|
|
to 0 or not set.
|
|
|
|
MUL_ZERO_WINS
|
|
"""""""""""""
|
|
|
|
The MUL TGSI operation (FP32 multiplication) will return 0 if either
|
|
of the operands are equal to 0. That means that 0 * Inf = 0. This
|
|
should be set the same way for an entire pipeline. Note that this
|
|
applies not only to the literal MUL TGSI opcode, but all FP32
|
|
multiplications implied by other operations, such as MAD, FMA, DP2,
|
|
DP3, DP4, DST, LOG, LRP, and possibly others. If there is a
|
|
mismatch between shaders, then it is unspecified whether this behavior
|
|
will be enabled.
|
|
|
|
FS_POST_DEPTH_COVERAGE
|
|
""""""""""""""""""""""
|
|
|
|
When enabled, the input for TGSI_SEMANTIC_SAMPLEMASK will exclude samples
|
|
that have failed the depth/stencil tests. This is only valid when
|
|
FS_EARLY_DEPTH_STENCIL is also specified.
|
|
|
|
LAYER_VIEWPORT_RELATIVE
|
|
"""""""""""""""""""""""
|
|
|
|
When enabled, the TGSI_SEMATNIC_LAYER output value is relative to the
|
|
current viewport. This is especially useful in conjunction with
|
|
TGSI_SEMANTIC_VIEWPORT_MASK.
|
|
|
|
|
|
Texture Sampling and Texture Formats
|
|
------------------------------------
|
|
|
|
This table shows how texture image components are returned as (x,y,z,w) tuples
|
|
by TGSI texture instructions, such as :opcode:`TEX`, :opcode:`TXD`, and
|
|
:opcode:`TXP`. For reference, OpenGL and Direct3D conventions are shown as
|
|
well.
|
|
|
|
+--------------------+--------------+--------------------+--------------+
|
|
| Texture Components | Gallium | OpenGL | Direct3D 9 |
|
|
+====================+==============+====================+==============+
|
|
| R | (r, 0, 0, 1) | (r, 0, 0, 1) | (r, 1, 1, 1) |
|
|
+--------------------+--------------+--------------------+--------------+
|
|
| RG | (r, g, 0, 1) | (r, g, 0, 1) | (r, g, 1, 1) |
|
|
+--------------------+--------------+--------------------+--------------+
|
|
| RGB | (r, g, b, 1) | (r, g, b, 1) | (r, g, b, 1) |
|
|
+--------------------+--------------+--------------------+--------------+
|
|
| RGBA | (r, g, b, a) | (r, g, b, a) | (r, g, b, a) |
|
|
+--------------------+--------------+--------------------+--------------+
|
|
| A | (0, 0, 0, a) | (0, 0, 0, a) | (0, 0, 0, a) |
|
|
+--------------------+--------------+--------------------+--------------+
|
|
| L | (l, l, l, 1) | (l, l, l, 1) | (l, l, l, 1) |
|
|
+--------------------+--------------+--------------------+--------------+
|
|
| LA | (l, l, l, a) | (l, l, l, a) | (l, l, l, a) |
|
|
+--------------------+--------------+--------------------+--------------+
|
|
| I | (i, i, i, i) | (i, i, i, i) | N/A |
|
|
+--------------------+--------------+--------------------+--------------+
|
|
| UV | XXX TBD | (0, 0, 0, 1) | (u, v, 1, 1) |
|
|
| | | [#envmap-bumpmap]_ | |
|
|
+--------------------+--------------+--------------------+--------------+
|
|
| Z | XXX TBD | (z, z, z, 1) | (0, z, 0, 1) |
|
|
| | | [#depth-tex-mode]_ | |
|
|
+--------------------+--------------+--------------------+--------------+
|
|
| S | (s, s, s, s) | unknown | unknown |
|
|
+--------------------+--------------+--------------------+--------------+
|
|
|
|
.. [#envmap-bumpmap] http://www.opengl.org/registry/specs/ATI/envmap_bumpmap.txt
|
|
.. [#depth-tex-mode] the default is (z, z, z, 1) but may also be (0, 0, 0, z)
|
|
or (z, z, z, z) depending on the value of GL_DEPTH_TEXTURE_MODE.
|