Name Strings

SPV_INTEL_shader_integer_functions2

Contact

See Issues list in the Khronos SPIRV-Registry repository: https://github.com/KhronosGroup/SPIRV-Registry

Contributors

  • Ian Romanick, Intel

  • Ben Ashbaugh, Intel

Notice

Copyright (c) 2018 The Khronos Group Inc. Copyright terms at http://www.khronos.org/registry/speccopyright.html

Status

Final Draft

Version

Last Modified Date

2019-01-22

Revision

2

Dependencies

This extension is written against the SPIR-V Specification, Version 1.3 Revision 1.

This extension requires SPIR-V 1.0.

Overview

This extension is written to provide the functionality of the INTEL_shader_integer_functions2, OpenGL Shading Language Specification extensions, to SPIR-V.

This extension introduces several new integer instructions to SPIR-V for use in graphics shaders. Many of these instructions have pre-existing counterparts in the Kernel environment.

Extension Name

To use this extension within a SPIR-V module, the following OpExtension must be present in the module:

OpExtension "SPV_INTEL_shader_integer_functions2"

New Capabilities

This extension introduces a new capability:

IntegerFunctions2INTEL

New Instructions

Instructions added under IntegerFunctions2INTEL capability.

OpUCountLeadingZeros
OpUCountTrailingZeros
OpAbsISub
OpAbsUSub
OpIAddSat
OpUAddSat
OpIAverage
OpUAverage
OpIAverageRounded
OpUAverageRounded
OpISubSat
OpUSubSat
OpIMul32x16
OpUMul32x16

Token Number Assignments

Name Value Usage

IntegerFunctions2INTEL

5584

Capability

OpUCountLeadingZeros

5585

Opcode

OpUCountTrailingZeros

5586

Opcode

OpAbsISub

5587

Opcode

OpAbsUSub

5588

Opcode

OpIAddSat

5589

Opcode

OpUAddSat

5590

Opcode

OpIAverage

5591

Opcode

OpUAverage

5592

Opcode

OpIAverageRounded

5593

Opcode

OpUAverageRounded

5594

Opcode

OpISubSat

5595

Opcode

OpUSubSat

5596

Opcode

OpIMul32x16

5597

Opcode

OpUMul32x16

5598

Opcode

Modifications to the SPIR-V Specification, Version 1.3

Capabilities

Modify Section 3.31, "Capability", adding these rows to the Capability table:

Capability Implicitly Declares

5584

IntegerFunctions2INTEL
Allow this new functionality…​

(Add to the table in 3.32.13, Arithmetic Instructions)

OpUCountLeadingZeros

Returns the number of leading 0-bits, starting at the most significant bit, in the binary representation of value. If value is zero, the size in bits of the type of value or component type of value (if value is a vector) will be returned.

Result Type must be a scalar or vector of integer type, whose Width operand is 32 and whose Signedness operand is 0.

The type of Operand must be the same as Result Type.

4

5585

<id>
Result Type

Result <id>

<id>
Operand

OpUCountTrailingZeros

Returns the number of trailing 0-bits, starting at the least significant bit, in the binary representation of value. If value is zero, the size in bits of the type of value or component type of value (if value is a vector) will be returned.

Result Type must be a scalar or vector of integer type, whose Width operand is 32 and whose Signedness operand is 0.

The type of Operand must be the same as Result Type.

4

5586

<id>
Result Type

Result <id>

<id>
Operand

OpAbsISub

Returns |x - y| clamped to the range of Result Type (instead of modulo overflowing).

Result Type must be a scalar or vector of integer type, whose Signedness operand is 0.

The type of Operand 1 and Operand 2 must be a scalar or vector of integer type. They must have the same number of components as Result Type. They must have the same component width as Result Type.

5

5587

<id>
Result Type

Result <id>

<id>
Operand 1

<id>
Operand 2

OpAbsUSub

Returns |x - y| clamped to the range of Result Type (instead of modulo overflowing).

Result Type must be a scalar or vector of integer type, whose Signedness operand is 0.

The type of Operand 1 and Operand 2 must be the same as Result Type.

5

5588

<id>
Result Type

Result <id>

<id>
Operand 1

<id>
Operand 2

OpIAddSat

Returns x + y clamped to the range of Result Type (instead of modulo overflowing).

Result Type must be a scalar or vector of integer type.

The type of Operand 1 and Operand 2 must be the same as Result Type.

5

5589

<id>
Result Type

Result <id>

<id>
Operand 1

<id>
Operand 2

OpUAddSat

Returns x + y clamped to the range of Result Type (instead of modulo overflowing).

Result Type must be a scalar or vector of integer type, whose Signedness operand is 0.

The type of Operand 1 and Operand 2 must be the same as Result Type.

5

5590

<id>
Result Type

Result <id>

<id>
Operand 1

<id>
Operand 2

OpIAverage

Returns (x+y) >> 1. The intermediate sum does not modulo overflow.

Result Type must be a scalar or vector of integer type.

The type of Operand 1 and Operand 2 must be the same as Result Type.

5

5591

<id>
Result Type

Result <id>

<id>
Operand 1

<id>
Operand 2

OpUAverage

Returns (x+y) >> 1. The intermediate sum does not modulo overflow.

Result Type must be a scalar or vector of integer type, whose Signedness operand is 0.

The type of Operand 1 and Operand 2 must be the same as Result Type.

5

5592

<id>
Result Type

Result <id>

<id>
Operand 1

<id>
Operand 2

OpIAverageRounded

Returns (x+y+1) >> 1. The intermediate sum does not modulo overflow.

Result Type must be a scalar or vector of integer type.

The type of Operand 1 and Operand 2 must be the same as Result Type.

5

5593

<id>
Result Type

Result <id>

<id>
Operand 1

<id>
Operand 2

OpUAverageRounded

Returns (x+y+1) >> 1. The intermediate sum does not modulo overflow.

Result Type must be a scalar or vector of integer type, whose Signedness operand is 0.

The type of Operand 1 and Operand 2 must be the same as Result Type.

5

5594

<id>
Result Type

Result <id>

<id>
Operand 1

<id>
Operand 2

OpISubSat

Returns x - y clamped to the range of Result Type (instead of modulo overflowing).

Result Type must be a scalar or vector of integer type.

The type of Operand 1 and Operand 2 must be the same as Result Type.

5

5595

<id>
Result Type

Result <id>

<id>
Operand 1

<id>
Operand 2

OpUSubSat

Returns x - y clamped to the range of Result Type (instead of modulo overflowing).

Result Type must be a scalar or vector of integer type, whose Signedness operand is 0.

The type of Operand 1 and Operand 2 must be the same as Result Type.

5

5596

<id>
Result Type

Result <id>

<id>
Operand 1

<id>
Operand 2

OpIMul32x16

Integer multiplication of Operand 1 and Operand 2. The low 16-bits of Operand 2 are sign extended to 32-bits before performing the multiplication.

Result Type must be a scalar or vector of integer type, whose Width operand is 32.

The type of Operand 1 and Operand 2 must be the same type as Result Type.

5

5597

<id>
Result Type

Result <id>

<id>
Operand 1

<id>
Operand 2

OpUMul32x16

Integer multiplication of Operand 1 and Operand 2. The high 16-bits of Operand 2 are replaced with 0x0000 before performing the multiplication.

Result Type must be a scalar or vector of integer type, whose Width operand is 32 and whose Signedness operand is 0.

The type of Operand 1 and Operand 2 must be the same type as Result Type.

5

5598

<id>
Result Type

Result <id>

<id>
Operand 1

<id>
Operand 2

Issues

None yet.

Revision History

Rev Date Author Changes

1

2018-09-10

idr

Initial revision

2

2019-01-22

idr

Remove all references to Signedness being 1