User Guide for SPIR-V Target

Introduction

The SPIR-V target provides code generation for the SPIR-V binary format described in the official SPIR-V specification.

Target Triples

For cross-compilation into SPIR-V use option

-target <Architecture><Subarchitecture>-<Vendor>-<OS>-<Environment>

to specify the target triple:

SPIR-V Architectures

Architecture	Description
spirv32	SPIR-V with 32-bit pointer width.
spirv64	SPIR-V with 64-bit pointer width.

SPIR-V Subarchitectures

Subarchitecture	Description
<empty>	SPIR-V version deduced by tools based on the compiled input.
v1.0	SPIR-V version 1.0.
v1.1	SPIR-V version 1.1.
v1.2	SPIR-V version 1.2.
v1.3	SPIR-V version 1.3.
v1.4	SPIR-V version 1.4.
v1.5	SPIR-V version 1.5.

SPIR-V Vendors

Vendor	Description
<empty>/unknown	Generic SPIR-V target without any vendor-specific settings.

Operating Systems

OS	Description
<empty>/unknown	Defaults to the OpenCL runtime.

SPIR-V Environments

Environment	Description
<empty>/unknown	Defaults to the OpenCL environment.

Example:

-target spirv64v1.0 can be used to compile for SPIR-V version 1.0 with 64-bit pointer width.

Representing special types in SPIR-V

SPIR-V specifies several kinds of opaque types. These types are represented using target extension types. These types are represented as follows:

SPIR-V Opaque Types

SPIR-V Type	LLVM type name	LLVM type arguments
OpTypeImage	spirv.Image	sampled type, dimensionality, depth, arrayed, MS, sampled, image format, access qualifier
OpTypeSampler	spirv.Sampler	(none)
OpTypeSampledImage	spirv.SampledImage	sampled type, dimensionality, depth, arrayed, MS, sampled, image format, access qualifier
OpTypeEvent	spirv.Event	(none)
OpTypeDeviceEvent	spirv.DeviceEvent	(none)
OpTypeReserveId	spirv.ReserveId	(none)
OpTypeQueue	spirv.Queue	(none)
OpTypePipe	spirv.Pipe	access qualifier
OpTypePipeStorage	spirv.PipeStorage	(none)

All integer arguments take the same value as they do in their corresponding SPIR-V instruction. For example, the OpenCL type image2d_depth_ro_t would be represented in SPIR-V IR as target("spirv.Image", void, 1, 1, 0, 0, 0, 0, 0), with its dimensionality parameter as 1 meaning 2D. Sampled image types include the parameters of its underlying image type, so that a sampled image for the previous type has the representation target("spirv.SampledImage, void, 1, 1, 0, 0, 0, 0, 0).