Issue 210514.1: Add GPU shading and kernel languages
| Author: | Stuart Brady |
|---|---|
| Champion: | Tony Tye |
| Date submitted: | 2021-05-14 |
| Date revised: | 2023-10-23 |
| Date closed: | 2023-10-16 |
| Type: | Enhancement |
| Status: | Accepted |
| DWARF version: | 6 |
Section 7.12, pg 231
Problem
Several common GPU shading and kernel languages are missing from the list of DWARF languages:
- OpenGL Shading Language
- OpenGL ES Shading Language
- High-Level Shading Language
- OpenCL C
- OpenCL C++
- C++ for OpenCL
- SYCL
This request does not list specific versions of each of the shading and kernel languages, partly on the basis that 210419.1 (or a refinement of that proposal) may be accepted. There are a great many versions of GLSL, in particular, and so adding separate language IDs for each language version does not seem practical. However, it would be desirable if a source language could be specified as being one of the shading or kernel languages without implicitly specifying a specific default version.
OpenCL
In DWARF 5, DW_LANG_OpenCL is unfortunately a misnomer. The correct name
would have been DW_LANG_OpenCL_C, as OpenCL refers to the host API and
C-based kernel language collectively, rather than the kernel language
alone, which would be more properly referred to as "OpenCL C".
It would be incorrect to use DW_LANG_OpenCL to refer to C++ for OpenCL
code, regardless of whether the OpenCL host API is used. Also, OpenCL C
can be used with other host APIs, e.g. a subset of the language can be
used with the Vulkan API.
If possible, it would therefore be desirable to rename DW_LANG_OpenCL to
DW_LANG_OpenCL_C, and to add DW_LANG_OpenCL as a (possibly deprecated)
alias for compatibility purposes, to avoid potential confusion.
Note that "C++ for OpenCL" and "OpenCL C++" are distinct languages. Although the latter is deprecated in OpenCL 3.0, its language ID within the SPIR-V specification can still occur in the SPIR-V representation of DWARF information provided by SPIR-V's "NonSemantic.Shader.DebugInfo.100" and "OpenCL.DebugInfo.100" specifications, and so requires a corresponding DWARF language ID.
GLSL
GLSL ES is often known as ESSL (and is referred to as ESSL within the SPIR-V specification). However, the name "GLSL ES" may be more meaningful to those not deeply familiar with these languages.
GLSL ES could be considered to be its own set of GLSL language versions, but it seems beneficial to treat GLSL and GLSL ES as separate languages, given that they have separate version histories.
DWARF 5 Proposal
Add the following GPU shading and kernel language names to Section 3.1.1, page 62 Table 3.1 Language names:
Language name Meaning DW_LANG_GLSLOpenGL Shading Language DW_LANG_GLSL_ESOpenGL ES Shading Language DW_LANG_HLSLHigh-Level Shading Language DW_LANG_OpenCL_CPPOpenCL C++ DW_LANG_CPP_for_OpenCLC++ for OpenCL DW_LANG_SYCLSYCL
Change the following in Table 3.1 Language names:
Language name Meaning DW_LANG_OpenCLOpenCL C
Add the following entries to Section 7.12, page 231 Table 7.17 Language encodings:
Language name Value Default Lower Bound DW_LANG_GLSL‡0x0034 0 DW_LANG_GLSL_ES‡0x0035 0 DW_LANG_HLSL‡0x0036 0 DW_LANG_OpenCL_CPP‡0x0037 0 DW_LANG_CPP_for_OpenCL‡0x0038 0 DW_LANG_SYCL‡0x0039 0
DWARF 6 (20221116) Proposal
Add the following GPU shading and kernel language names to Section 3.1.1, page 63 Table 3.1 Language names:
Language name Meaning Version Scheme DW_LNAME_GLSLOpenGL Shading Language VVMMPP DW_LNAME_GLSL_ESOpenGL ES Shading Language VVMMPP DW_LNAME_HLSLHigh-Level Shading Language YYYY DW_LNAME_OpenCL_COpenCL C VVMM DW_LNAME_OpenCL_CPPOpenCL C++ VVMM DW_LNAME_CPP_for_OpenCLC++ for OpenCL VVMM DW_LNAME_SYCLSYCL YYYYRR
Remove the following from Table 3.1 Language names:
Language name Meaning Version Scheme DW_LNAME_OpenCLOpenCL
Add the following to Table 3.2 Version Encoding Schemes:
Scheme Encoding VVMMPP Major version number times 10,000 plus the minor version number times 100 plus the patch version number. For example, 30607 represents version 3.6.7 while 31215 represents version 3.12.15. YYYYRR Year in which the language definition was released times 100 plus the revision number. For example, 202007 represents version 2020 revision 7 while 202011 represents version 2020 revision 11.
Add the following entries to Section 7.12, page 235 Table 7.17 Language encodings:
Language name Value Default Lower Bound DW_LNAME_OpenCL_C0x0014 0 DW_LNAME_GLSL‡0x0020 0 DW_LNAME_GLSL_ES‡0x0021 0 DW_LNAME_HLSL‡0x0022 0 DW_LNAME_OpenCL_CPP‡0x0023 0 DW_LNAME_CPP_for_OpenCL‡0x0024 0 DW_LNAME_SYCL‡0x0025 0
Remove the following entry from Section 7.12, page 235 Table 7.17 Language encodings:
Language name Value Default Lower Bound DW_LNAME_OpenCL0x0014 0
References
2023-08-06: Rewritten into formal proposal.
2023-10-23: Accepted with minor editorial corrections; updated assigned values.
