1056 lines
40 KiB
ReStructuredText
1056 lines
40 KiB
ReStructuredText
=================================================
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Syntax of AMDGPU Assembler Operands and Modifiers
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=================================================
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.. contents::
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:local:
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Conventions
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===========
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The following conventions are used in syntax description:
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=================== =============================================================
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Notation Description
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=================== =============================================================
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{0..N} Any integer value in the range from 0 to N (inclusive).
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Unless stated otherwise, this value may be specified as
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either a literal or an llvm expression.
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<x> Syntax and meaning of *<x>* is explained elsewhere.
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=================== =============================================================
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.. _amdgpu_syn_operands:
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Operands
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========
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TBD
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.. _amdgpu_syn_modifiers:
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Modifiers
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=========
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DS Modifiers
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------------
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.. _amdgpu_synid_ds_offset8:
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ds_offset8
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~~~~~~~~~~
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Specifies an immediate unsigned 8-bit offset, in bytes. The default value is 0.
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Used with DS instructions which have 2 addresses.
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======================================== ================================================
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Syntax Description
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======================================== ================================================
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offset:{0..0xFF} Specifies a 8-bit offset.
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======================================== ================================================
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.. _amdgpu_synid_ds_offset16:
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ds_offset16
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~~~~~~~~~~~
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Specifies an immediate unsigned 16-bit offset, in bytes. The default value is 0.
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Used with DS instructions which have 1 address.
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======================================== ================================================
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Syntax Description
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======================================== ================================================
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offset:{0..0xFFFF} Specifies a 16-bit offset.
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======================================== ================================================
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.. _amdgpu_synid_sw_offset16:
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sw_offset16
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~~~~~~~~~~~
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This is a special modifier which may be used with *ds_swizzle_b32* instruction only.
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Specifies a sizzle pattern in numeric or symbolic form. The default value is 0.
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See AMD documentation for more information.
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======================================================= ===================================================
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Syntax Description
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======================================================= ===================================================
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offset:{0..0xFFFF} Specifies a 16-bit swizzle pattern
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in a numeric form.
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offset:swizzle(QUAD_PERM,{0..3},{0..3},{0..3},{0..3}) Specifies a quad permute mode pattern; each
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number is a lane id.
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offset:swizzle(BITMASK_PERM, "<mask>") Specifies a bitmask permute mode pattern
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which converts a 5-bit lane id to another
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lane id with which the lane interacts.
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<mask> is a 5 character sequence which
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specifies how to transform the bits of the
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lane id. The following characters are allowed:
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* "0" - set bit to 0.
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* "1" - set bit to 1.
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* "p" - preserve bit.
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* "i" - inverse bit.
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offset:swizzle(BROADCAST,{2..32},{0..N}) Specifies a broadcast mode.
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Broadcasts the value of any particular lane to
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all lanes in its group.
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The first numeric parameter is a group
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size and must be equal to 2, 4, 8, 16 or 32.
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The second numeric parameter is an index of the
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lane being broadcasted. The index must not exceed
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group size.
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offset:swizzle(SWAP,{1..16}) Specifies a swap mode.
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Swaps the neighboring groups of
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1, 2, 4, 8 or 16 lanes.
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offset:swizzle(REVERSE,{2..32}) Specifies a reverse mode. Reverses
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the lanes for groups of 2, 4, 8, 16 or 32 lanes.
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======================================================= ===================================================
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.. _amdgpu_synid_gds:
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gds
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~~~
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Specifies whether to use GDS or LDS memory (LDS is the default).
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======================================== ================================================
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Syntax Description
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======================================== ================================================
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gds Use GDS memory.
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======================================== ================================================
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EXP Modifiers
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-------------
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.. _amdgpu_synid_done:
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done
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~~~~
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Specifies if this is the last export from the shader to the target. By default, current
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instruction does not finish an export sequence.
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======================================== ================================================
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Syntax Description
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======================================== ================================================
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done Indicates the last export operation.
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======================================== ================================================
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.. _amdgpu_synid_compr:
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compr
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~~~~~
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Indicates if the data are compressed (not compressed by default).
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======================================== ================================================
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Syntax Description
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======================================== ================================================
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compr Data are compressed.
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======================================== ================================================
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.. _amdgpu_synid_vm:
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vm
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~~
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Specifies valid mask flag state (off by default).
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======================================== ================================================
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Syntax Description
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======================================== ================================================
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vm Set valid mask flag.
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======================================== ================================================
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FLAT Modifiers
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--------------
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.. _amdgpu_synid_flat_offset12:
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flat_offset12
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~~~~~~~~~~~~~
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Specifies an immediate unsigned 12-bit offset, in bytes. The default value is 0.
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Cannot be used with *global/scratch* opcodes. GFX9 only.
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======================================== ================================================
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Syntax Description
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======================================== ================================================
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offset:{0..4095} Specifies a 12-bit unsigned offset.
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======================================== ================================================
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.. _amdgpu_synid_flat_offset13:
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flat_offset13
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~~~~~~~~~~~~~
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Specifies an immediate signed 13-bit offset, in bytes. The default value is 0.
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Can be used with *global/scratch* opcodes only. GFX9 only.
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======================================== ================================================
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Syntax Description
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======================================== ================================================
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offset:{-4096..+4095} Specifies a 13-bit signed offset.
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======================================== ================================================
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glc
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~~~
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See a description :ref:`here<amdgpu_synid_glc>`.
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slc
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~~~
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See a description :ref:`here<amdgpu_synid_slc>`.
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tfe
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~~~
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See a description :ref:`here<amdgpu_synid_tfe>`.
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nv
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~~
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See a description :ref:`here<amdgpu_synid_nv>`.
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MIMG Modifiers
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--------------
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.. _amdgpu_synid_dmask:
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dmask
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~~~~~
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Specifies which channels (image components) are used by the operation. By default, no channels
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are used.
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======================================== ================================================
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Syntax Description
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======================================== ================================================
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dmask:{0..15} Each bit corresponds to one of 4 image
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components (RGBA). If the specified bit value
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is 0, the component is not used, value 1 means
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that the component is used.
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======================================== ================================================
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This modifier has some limitations depending on instruction kind:
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======================================== ================================================
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Instruction Kind Valid dmask Values
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======================================== ================================================
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32-bit atomic cmpswap 0x3
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other 32-bit atomic instructions 0x1
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64-bit atomic cmpswap 0xF
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other 64-bit atomic instructions 0x3
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GATHER4 0x1, 0x2, 0x4, 0x8
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Other instructions any value
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======================================== ================================================
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.. _amdgpu_synid_unorm:
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unorm
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~~~~~
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Specifies whether address is normalized or not (normalized by default).
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======================================== ================================================
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Syntax Description
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======================================== ================================================
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unorm Force address to be un-normalized.
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======================================== ================================================
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glc
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~~~
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See a description :ref:`here<amdgpu_synid_glc>`.
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slc
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~~~
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See a description :ref:`here<amdgpu_synid_slc>`.
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.. _amdgpu_synid_r128:
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r128
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~~~~
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Specifies texture resource size. The default size is 256 bits.
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GFX7 and GFX8 only.
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======================================== ================================================
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Syntax Description
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======================================== ================================================
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r128 Specifies 128 bits texture resource size.
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======================================== ================================================
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tfe
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~~~
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See a description :ref:`here<amdgpu_synid_tfe>`.
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.. _amdgpu_synid_lwe:
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lwe
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~~~
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Specifies LOD warning status (LOD warning is disabled by default).
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======================================== ================================================
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Syntax Description
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======================================== ================================================
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lwe Enables LOD warning.
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======================================== ================================================
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.. _amdgpu_synid_da:
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da
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~~
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Specifies if an array index must be sent to TA. By default, array index is not sent.
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======================================== ================================================
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Syntax Description
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======================================== ================================================
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da Send an array-index to TA.
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======================================== ================================================
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.. _amdgpu_synid_d16:
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d16
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~~~
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Specifies data size: 16 or 32 bits (32 bits by default). Not supported by GFX7.
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======================================== ================================================
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Syntax Description
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======================================== ================================================
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d16 Enables 16-bits data mode.
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On loads, convert data in memory to 16-bit
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format before storing it in VGPRs.
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For stores, convert 16-bit data in VGPRs to
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32 bits before going to memory.
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Note that 16-bit data are stored in VGPRs
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unpacked in GFX8.0. In GFX8.1 and GFX9 16-bit
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data are packed.
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======================================== ================================================
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.. _amdgpu_synid_a16:
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a16
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~~~
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Specifies size of image address components: 16 or 32 bits (32 bits by default). GFX9 only.
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======================================== ================================================
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Syntax Description
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======================================== ================================================
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a16 Enables 16-bits image address components.
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======================================== ================================================
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Miscellaneous Modifiers
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-----------------------
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.. _amdgpu_synid_glc:
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glc
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~~~
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This modifier has different meaning for loads, stores, and atomic operations.
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The default value is off (0).
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See AMD documentation for details.
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======================================== ================================================
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Syntax Description
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======================================== ================================================
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glc Set glc bit to 1.
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======================================== ================================================
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.. _amdgpu_synid_slc:
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slc
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~~~
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Specifies cache policy. The default value is off (0).
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See AMD documentation for details.
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======================================== ================================================
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Syntax Description
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======================================== ================================================
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slc Set slc bit to 1.
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======================================== ================================================
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.. _amdgpu_synid_tfe:
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tfe
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~~~
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Controls access to partially resident textures. The default value is off (0).
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See AMD documentation for details.
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======================================== ================================================
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Syntax Description
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======================================== ================================================
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tfe Set tfe bit to 1.
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======================================== ================================================
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.. _amdgpu_synid_nv:
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nv
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~~
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Specifies if instruction is operating on non-volatile memory. By default, memory is volatile.
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GFX9 only.
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======================================== ================================================
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Syntax Description
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======================================== ================================================
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nv Indicates that instruction operates on
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non-volatile memory.
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======================================== ================================================
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MUBUF/MTBUF Modifiers
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---------------------
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.. _amdgpu_synid_idxen:
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idxen
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~~~~~
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Specifies whether address components include an index. By default, no components are used.
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Can be used together with :ref:`offen<amdgpu_synid_offen>`.
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Cannot be used with :ref:`addr64<amdgpu_synid_addr64>`.
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======================================== ================================================
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Syntax Description
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======================================== ================================================
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idxen Address components include an index.
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======================================== ================================================
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.. _amdgpu_synid_offen:
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offen
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~~~~~
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Specifies whether address components include an offset. By default, no components are used.
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Can be used together with :ref:`idxen<amdgpu_synid_idxen>`.
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Cannot be used with :ref:`addr64<amdgpu_synid_addr64>`.
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======================================== ================================================
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Syntax Description
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======================================== ================================================
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offen Address components include an offset.
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======================================== ================================================
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.. _amdgpu_synid_addr64:
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addr64
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~~~~~~
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Specifies whether a 64-bit address is used. By default, no address is used.
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GFX7 only. Cannot be used with :ref:`offen<amdgpu_synid_offen>` and
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:ref:`idxen<amdgpu_synid_idxen>` modifiers.
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======================================== ================================================
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Syntax Description
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======================================== ================================================
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addr64 A 64-bit address is used.
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======================================== ================================================
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.. _amdgpu_synid_buf_offset12:
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buf_offset12
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~~~~~~~~~~~~
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Specifies an immediate unsigned 12-bit offset, in bytes. The default value is 0.
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======================================== ================================================
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Syntax Description
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======================================== ================================================
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offset:{0..0xFFF} Specifies a 12-bit unsigned offset.
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======================================== ================================================
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glc
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~~~
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See a description :ref:`here<amdgpu_synid_glc>`.
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slc
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~~~
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See a description :ref:`here<amdgpu_synid_slc>`.
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.. _amdgpu_synid_lds:
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lds
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~~~
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Specifies where to store the result: VGPRs or LDS (VGPRs by default).
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======================================== ================================================
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Syntax Description
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======================================== ================================================
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lds Store result in LDS.
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======================================== ================================================
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tfe
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~~~
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See a description :ref:`here<amdgpu_synid_tfe>`.
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.. _amdgpu_synid_dfmt:
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dfmt
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~~~~
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TBD
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.. _amdgpu_synid_nfmt:
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nfmt
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~~~~
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TBD
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SMRD/SMEM Modifiers
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-------------------
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glc
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~~~
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See a description :ref:`here<amdgpu_synid_glc>`.
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nv
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~~
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See a description :ref:`here<amdgpu_synid_nv>`.
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VINTRP Modifiers
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----------------
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.. _amdgpu_synid_high:
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high
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~~~~
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Specifies which half of the LDS word to use. Low half of LDS word is used by default.
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GFX9 only.
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======================================== ================================================
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Syntax Description
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======================================== ================================================
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high Use high half of LDS word.
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======================================== ================================================
|
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VOP1/VOP2 DPP Modifiers
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-----------------------
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GFX8 and GFX9 only.
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.. _amdgpu_synid_dpp_ctrl:
|
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dpp_ctrl
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~~~~~~~~
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Specifies how data are shared between threads. This is a mandatory modifier.
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There is no default value.
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Note. The lanes of a wavefront are organized in four banks and four rows.
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======================================== ================================================
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Syntax Description
|
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======================================== ================================================
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quad_perm:[{0..3},{0..3},{0..3},{0..3}] Full permute of 4 threads.
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row_mirror Mirror threads within row.
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row_half_mirror Mirror threads within 1/2 row (8 threads).
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row_bcast:15 Broadcast 15th thread of each row to next row.
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row_bcast:31 Broadcast thread 31 to rows 2 and 3.
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wave_shl:1 Wavefront left shift by 1 thread.
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wave_rol:1 Wavefront left rotate by 1 thread.
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wave_shr:1 Wavefront right shift by 1 thread.
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wave_ror:1 Wavefront right rotate by 1 thread.
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row_shl:{1..15} Row shift left by 1-15 threads.
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row_shr:{1..15} Row shift right by 1-15 threads.
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row_ror:{1..15} Row rotate right by 1-15 threads.
|
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======================================== ================================================
|
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.. _amdgpu_synid_row_mask:
|
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row_mask
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~~~~~~~~
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Controls which rows are enabled for data sharing. By default, all rows are enabled.
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Note. The lanes of a wavefront are organized in four banks and four rows.
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======================================== ================================================
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Syntax Description
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======================================== ================================================
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row_mask:{0..15} Each of 4 bits in the mask controls one
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row (0 - disabled, 1 - enabled).
|
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======================================== ================================================
|
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|
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.. _amdgpu_synid_bank_mask:
|
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|
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bank_mask
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~~~~~~~~~
|
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Controls which banks are enabled for data sharing. By default, all banks are enabled.
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|
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Note. The lanes of a wavefront are organized in four banks and four rows.
|
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|
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======================================== ================================================
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Syntax Description
|
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======================================== ================================================
|
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bank_mask:{0..15} Each of 4 bits in the mask controls one
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bank (0 - disabled, 1 - enabled).
|
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======================================== ================================================
|
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|
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.. _amdgpu_synid_bound_ctrl:
|
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|
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bound_ctrl
|
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~~~~~~~~~~
|
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|
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Controls data sharing when accessing an invalid lane. By default, data sharing with
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invalid lanes is disabled.
|
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|
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======================================== ================================================
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Syntax Description
|
|
======================================== ================================================
|
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bound_ctrl:0 Enables data sharing with invalid lanes.
|
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Accessing data from an invalid lane will
|
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return zero.
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======================================== ================================================
|
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|
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VOP1/VOP2/VOPC SDWA Modifiers
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-----------------------------
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|
|
GFX8 and GFX9 only.
|
|
|
|
clamp
|
|
~~~~~
|
|
|
|
See a description :ref:`here<amdgpu_synid_clamp>`.
|
|
|
|
omod
|
|
~~~~
|
|
|
|
See a description :ref:`here<amdgpu_synid_omod>`.
|
|
|
|
GFX9 only.
|
|
|
|
.. _amdgpu_synid_dst_sel:
|
|
|
|
dst_sel
|
|
~~~~~~~
|
|
|
|
Selects which bits in the destination are affected. By default, all bits are affected.
|
|
|
|
======================================== ================================================
|
|
Syntax Description
|
|
======================================== ================================================
|
|
dst_sel:DWORD Use bits 31:0.
|
|
dst_sel:BYTE_0 Use bits 7:0.
|
|
dst_sel:BYTE_1 Use bits 15:8.
|
|
dst_sel:BYTE_2 Use bits 23:16.
|
|
dst_sel:BYTE_3 Use bits 31:24.
|
|
dst_sel:WORD_0 Use bits 15:0.
|
|
dst_sel:WORD_1 Use bits 31:16.
|
|
======================================== ================================================
|
|
|
|
|
|
.. _amdgpu_synid_dst_unused:
|
|
|
|
dst_unused
|
|
~~~~~~~~~~
|
|
|
|
Controls what to do with the bits in the destination which are not selected
|
|
by :ref:`dst_sel<amdgpu_synid_dst_sel>`.
|
|
By default, unused bits are preserved.
|
|
|
|
======================================== ================================================
|
|
Syntax Description
|
|
======================================== ================================================
|
|
dst_unused:UNUSED_PAD Pad with zeros.
|
|
dst_unused:UNUSED_SEXT Sign-extend upper bits, zero lower bits.
|
|
dst_unused:UNUSED_PRESERVE Preserve bits.
|
|
======================================== ================================================
|
|
|
|
.. _amdgpu_synid_src0_sel:
|
|
|
|
src0_sel
|
|
~~~~~~~~
|
|
|
|
Controls which bits in the src0 are used. By default, all bits are used.
|
|
|
|
======================================== ================================================
|
|
Syntax Description
|
|
======================================== ================================================
|
|
src0_sel:DWORD Use bits 31:0.
|
|
src0_sel:BYTE_0 Use bits 7:0.
|
|
src0_sel:BYTE_1 Use bits 15:8.
|
|
src0_sel:BYTE_2 Use bits 23:16.
|
|
src0_sel:BYTE_3 Use bits 31:24.
|
|
src0_sel:WORD_0 Use bits 15:0.
|
|
src0_sel:WORD_1 Use bits 31:16.
|
|
======================================== ================================================
|
|
|
|
.. _amdgpu_synid_src1_sel:
|
|
|
|
src1_sel
|
|
~~~~~~~~
|
|
|
|
Controls which bits in the src1 are used. By default, all bits are used.
|
|
|
|
======================================== ================================================
|
|
Syntax Description
|
|
======================================== ================================================
|
|
src1_sel:DWORD Use bits 31:0.
|
|
src1_sel:BYTE_0 Use bits 7:0.
|
|
src1_sel:BYTE_1 Use bits 15:8.
|
|
src1_sel:BYTE_2 Use bits 23:16.
|
|
src1_sel:BYTE_3 Use bits 31:24.
|
|
src1_sel:WORD_0 Use bits 15:0.
|
|
src1_sel:WORD_1 Use bits 31:16.
|
|
======================================== ================================================
|
|
|
|
VOP1/VOP2/VOPC SDWA Operand Modifiers
|
|
-------------------------------------
|
|
|
|
Operand modifiers are not used separately. They are applied to source operands.
|
|
|
|
GFX8 and GFX9 only.
|
|
|
|
abs
|
|
~~~
|
|
|
|
See a description :ref:`here<amdgpu_synid_abs>`.
|
|
|
|
neg
|
|
~~~
|
|
|
|
See a description :ref:`here<amdgpu_synid_neg>`.
|
|
|
|
.. _amdgpu_synid_sext:
|
|
|
|
sext
|
|
~~~~
|
|
|
|
Sign-extends value of a (sub-dword) operand to fill all 32 bits.
|
|
Has no effect for 32-bit operands.
|
|
|
|
Valid for integer operands only.
|
|
|
|
======================================== ================================================
|
|
Syntax Description
|
|
======================================== ================================================
|
|
sext(<operand>) Sign-extend operand value.
|
|
======================================== ================================================
|
|
|
|
VOP3 Modifiers
|
|
--------------
|
|
|
|
.. _amdgpu_synid_vop3_op_sel:
|
|
|
|
vop3_op_sel
|
|
~~~~~~~~~~~
|
|
|
|
Selects the low [15:0] or high [31:16] operand bits for source and destination operands.
|
|
By default, low bits are used for all operands.
|
|
|
|
The number of values specified with the op_sel modifier must match the number of instruction
|
|
operands (both source and destination). First value controls src0, second value controls src1
|
|
and so on, except that the last value controls destination.
|
|
The value 0 selects the low bits, while 1 selects the high bits.
|
|
|
|
Note. op_sel modifier affects 16-bit operands only. For 32-bit operands the value specified
|
|
by op_sel must be 0.
|
|
|
|
GFX9 only.
|
|
|
|
======================================== ============================================================
|
|
Syntax Description
|
|
======================================== ============================================================
|
|
op_sel:[{0..1},{0..1}] Select operand bits for instructions with 1 source operand.
|
|
op_sel:[{0..1},{0..1},{0..1}] Select operand bits for instructions with 2 source operands.
|
|
op_sel:[{0..1},{0..1},{0..1},{0..1}] Select operand bits for instructions with 3 source operands.
|
|
======================================== ============================================================
|
|
|
|
.. _amdgpu_synid_clamp:
|
|
|
|
clamp
|
|
~~~~~
|
|
|
|
Clamp meaning depends on instruction.
|
|
|
|
For *v_cmp* instructions, clamp modifier indicates that the compare signals
|
|
if a floating point exception occurs. By default, signaling is disabled.
|
|
Not supported by GFX7.
|
|
|
|
For integer operations, clamp modifier indicates that the result must be clamped
|
|
to the largest and smallest representable value. By default, there is no clamping.
|
|
Integer clamping is not supported by GFX7.
|
|
|
|
For floating point operations, clamp modifier indicates that the result must be clamped
|
|
to the range [0.0, 1.0]. By default, there is no clamping.
|
|
|
|
Note. Clamp modifier is applied after :ref:`output modifiers<amdgpu_synid_omod>` (if any).
|
|
|
|
======================================== ================================================
|
|
Syntax Description
|
|
======================================== ================================================
|
|
clamp Enables clamping (or signaling).
|
|
======================================== ================================================
|
|
|
|
.. _amdgpu_synid_omod:
|
|
|
|
omod
|
|
~~~~
|
|
|
|
Specifies if an output modifier must be applied to the result.
|
|
By default, no output modifiers are applied.
|
|
|
|
Note. Output modifiers are applied before :ref:`clamping<amdgpu_synid_clamp>` (if any).
|
|
|
|
Output modifiers are valid for f32 and f64 floating point results only.
|
|
They must not be used with f16.
|
|
|
|
Note. *v_cvt_f16_f32* is an exception. This instruction produces f16 result
|
|
but accepts output modifiers.
|
|
|
|
======================================== ================================================
|
|
Syntax Description
|
|
======================================== ================================================
|
|
mul:2 Multiply the result by 2.
|
|
mul:4 Multiply the result by 4.
|
|
div:2 Multiply the result by 0.5.
|
|
======================================== ================================================
|
|
|
|
VOP3 Operand Modifiers
|
|
----------------------
|
|
|
|
Operand modifiers are not used separately. They are applied to source operands.
|
|
|
|
.. _amdgpu_synid_abs:
|
|
|
|
abs
|
|
~~~
|
|
|
|
Computes absolute value of its operand. Applied before :ref:`neg<amdgpu_synid_neg>` (if any).
|
|
Valid for floating point operands only.
|
|
|
|
======================================== ================================================
|
|
Syntax Description
|
|
======================================== ================================================
|
|
abs(<operand>) Get absolute value of operand.
|
|
\|<operand>| The same as above.
|
|
======================================== ================================================
|
|
|
|
.. _amdgpu_synid_neg:
|
|
|
|
neg
|
|
~~~
|
|
|
|
Computes negative value of its operand. Applied after :ref:`abs<amdgpu_synid_abs>` (if any).
|
|
Valid for floating point operands only.
|
|
|
|
======================================== ================================================
|
|
Syntax Description
|
|
======================================== ================================================
|
|
neg(<operand>) Get negative value of operand.
|
|
-<operand> The same as above.
|
|
======================================== ================================================
|
|
|
|
VOP3P Modifiers
|
|
---------------
|
|
|
|
This section describes modifiers of regular VOP3P instructions.
|
|
*v_mad_mix* modifiers are described :ref:`in a separate section<amdgpu_synid_mad_mix>`.
|
|
|
|
GFX9 only.
|
|
|
|
.. _amdgpu_synid_op_sel:
|
|
|
|
op_sel
|
|
~~~~~~
|
|
|
|
Selects the low [15:0] or high [31:16] operand bits as input to the operation
|
|
which results in the lower-half of the destination.
|
|
By default, low bits are used for all operands.
|
|
|
|
The number of values specified with the op_sel modifier must match the number of source
|
|
operands. First value controls src0, second value controls src1 and so on.
|
|
The value 0 selects the low bits, while 1 selects the high bits.
|
|
|
|
======================================== =============================================================
|
|
Syntax Description
|
|
======================================== =============================================================
|
|
op_sel:[{0..1}] Select operand bits for instructions with 1 source operand.
|
|
op_sel:[{0..1},{0..1}] Select operand bits for instructions with 2 source operands.
|
|
op_sel:[{0..1},{0..1},{0..1}] Select operand bits for instructions with 3 source operands.
|
|
======================================== =============================================================
|
|
|
|
.. _amdgpu_synid_op_sel_hi:
|
|
|
|
op_sel_hi
|
|
~~~~~~~~~
|
|
|
|
Selects the low [15:0] or high [31:16] operand bits as input to the operation
|
|
which results in the upper-half of the destination.
|
|
By default, high bits are used for all operands.
|
|
|
|
The number of values specified with the op_sel_hi modifier must match the number of source
|
|
operands. First value controls src0, second value controls src1 and so on.
|
|
The value 0 selects the low bits, while 1 selects the high bits.
|
|
|
|
======================================== =============================================================
|
|
Syntax Description
|
|
======================================== =============================================================
|
|
op_sel_hi:[{0..1}] Select operand bits for instructions with 1 source operand.
|
|
op_sel_hi:[{0..1},{0..1}] Select operand bits for instructions with 2 source operands.
|
|
op_sel_hi:[{0..1},{0..1},{0..1}] Select operand bits for instructions with 3 source operands.
|
|
======================================== =============================================================
|
|
|
|
.. _amdgpu_synid_neg_lo:
|
|
|
|
neg_lo
|
|
~~~~~~
|
|
|
|
Specifies whether to change sign of operand values selected by
|
|
:ref:`op_sel<amdgpu_synid_op_sel>`. These values are then used
|
|
as input to the operation which results in the upper-half of the destination.
|
|
|
|
The number of values specified with this modifier must match the number of source
|
|
operands. First value controls src0, second value controls src1 and so on.
|
|
|
|
The value 0 indicates that the corresponding operand value is used unmodified,
|
|
the value 1 indicates that negative value of the operand must be used.
|
|
|
|
By default, operand values are used unmodified.
|
|
|
|
This modifier is valid for floating point operands only.
|
|
|
|
======================================== ==================================================================
|
|
Syntax Description
|
|
======================================== ==================================================================
|
|
neg_lo:[{0..1}] Select affected operands for instructions with 1 source operand.
|
|
neg_lo:[{0..1},{0..1}] Select affected operands for instructions with 2 source operands.
|
|
neg_lo:[{0..1},{0..1},{0..1}] Select affected operands for instructions with 3 source operands.
|
|
======================================== ==================================================================
|
|
|
|
.. _amdgpu_synid_neg_hi:
|
|
|
|
neg_hi
|
|
~~~~~~
|
|
|
|
Specifies whether to change sign of operand values selected by
|
|
:ref:`op_sel_hi<amdgpu_synid_op_sel_hi>`. These values are then used
|
|
as input to the operation which results in the upper-half of the destination.
|
|
|
|
The number of values specified with this modifier must match the number of source
|
|
operands. First value controls src0, second value controls src1 and so on.
|
|
|
|
The value 0 indicates that the corresponding operand value is used unmodified,
|
|
the value 1 indicates that negative value of the operand must be used.
|
|
|
|
By default, operand values are used unmodified.
|
|
|
|
This modifier is valid for floating point operands only.
|
|
|
|
======================================== ==================================================================
|
|
Syntax Description
|
|
======================================== ==================================================================
|
|
neg_hi:[{0..1}] Select affected operands for instructions with 1 source operand.
|
|
neg_hi:[{0..1},{0..1}] Select affected operands for instructions with 2 source operands.
|
|
neg_hi:[{0..1},{0..1},{0..1}] Select affected operands for instructions with 3 source operands.
|
|
======================================== ==================================================================
|
|
|
|
clamp
|
|
~~~~~
|
|
|
|
See a description :ref:`here<amdgpu_synid_clamp>`.
|
|
|
|
.. _amdgpu_synid_mad_mix:
|
|
|
|
VOP3P V_MAD_MIX Modifiers
|
|
-------------------------
|
|
|
|
These instructions use VOP3P format but have different modifiers.
|
|
|
|
GFX9 only.
|
|
|
|
.. _amdgpu_synid_mad_mix_op_sel:
|
|
|
|
mad_mix_op_sel
|
|
~~~~~~~~~~~~~~
|
|
|
|
This operand has meaning only for 16-bit source operands as indicated by
|
|
:ref:`mad_mix_op_sel_hi<amdgpu_synid_mad_mix_op_sel_hi>`.
|
|
It specifies to select either the low [15:0] or high [31:16] operand bits
|
|
as input to the operation.
|
|
|
|
The value 0 indicates the low bits, the value 1 indicates the high 16 bits.
|
|
By default, low bits are used for all operands.
|
|
|
|
======================================== ================================================
|
|
Syntax Description
|
|
======================================== ================================================
|
|
op_sel:[{0..1},{0..1},{0..1}] Select location of each 16-bit source operand.
|
|
======================================== ================================================
|
|
|
|
.. _amdgpu_synid_mad_mix_op_sel_hi:
|
|
|
|
mad_mix_op_sel_hi
|
|
~~~~~~~~~~~~~~~~~
|
|
|
|
Selects the size of source operands: either 32 bits or 16 bits.
|
|
By default, 32 bits are used for all source operands.
|
|
|
|
The value 0 indicates 32 bits, the value 1 indicates 16 bits.
|
|
The location of 16 bits in the operand may be specified by
|
|
:ref:`mad_mix_op_sel<amdgpu_synid_mad_mix_op_sel>`.
|
|
|
|
======================================== ================================================
|
|
Syntax Description
|
|
======================================== ================================================
|
|
op_sel_hi:[{0..1},{0..1},{0..1}] Select size of each source operand.
|
|
======================================== ================================================
|
|
|
|
abs
|
|
~~~
|
|
|
|
See a description :ref:`here<amdgpu_synid_abs>`.
|
|
|
|
neg
|
|
~~~
|
|
|
|
See a description :ref:`here<amdgpu_synid_neg>`.
|
|
|
|
clamp
|
|
~~~~~
|
|
|
|
See a description :ref:`here<amdgpu_synid_clamp>`.
|