The goal of this PR is to facilitate integration of SPIRV Backend into
misc 3rd party tools and libraries by means of exposing an API call that
translate LLVM module to SPIR-V and write results into a string as
binary SPIR-V output, providing diagnostics on fail and means of
configuring translation in a style of command line options.
An example of a use case may be Khronos Translator that provides
bidirectional translation LLVM IR <=> SPIR-V, where LLVM IR => SPIR-V
step may be substituted by the call to SPIR-V Backend API, implemented
by this PR.
This commit introduces emission of DebugSource, DebugCompileUnit from
NonSemantic.Shader.DebugInfo.100 and required OpString with filename.
NonSemantic.Shader.DebugInfo.100 is divided, following DWARF into two
main concepts – emitting DIE and Line.
In DWARF .debug_abbriev and .debug_info sections are responsible for
emitting tree with information (DEIs) about e.g. types, compilation
unit. Corresponding to that in NonSemantic.Shader.DebugInfo.100 have
instructions like DebugSource, DebugCompileUnit etc. which preforms same
role in SPIR-V file. The difference is in fact that in SPIR-V there are
no sections but logical layout which forces order of the instruction
emission.
The NonSemantic.Shader.DebugInfo.100 requires for this type of global
information to be emitted after OpTypeXXX and OpConstantXXX
instructions.
One of the goals was to minimize changes and interaction with
SPIRVModuleAnalysis as possible which current commit achieves by
emitting it’s instructions directly into MachineFunction.
The possibility of duplicates are mitigated by guard inside pass which
emits the global information only once in one function.
By that method duplicates don’t have chance to be emitted.
From that point, adding new debug global instructions should be
straightforward.
This PR introduces support of llvm.ptr.annotation to SPIR-V Backend, and
implement several extensions which make use of spirv.Decorations and
llvm.ptr.annotation to annotate global variables and pointers:
- SPV_INTEL_cache_controls
- SPV_INTEL_global_variable_host_access
- SPV_INTEL_global_variable_fpga_decorations
This PR introduces support for inline assembly calls for SPIR-V Backend
in general, and support for SPV_INTEL_inline_assembly [1] extension in
particular. The former part of the PR is agnostic towards
vendor-specific requirements and resolves the task of supporting
successful transformation of inline assembly as long as it's possible
without specific SPIR-V instruction codes.
As a part of the PR there appears an opportunity to bring coherent
inline assembly information up to latest passes of the transformation
process (emitting final SPIR-V instructions), so that PR makes it easy
to add any another required flavor of inline assembly, other then
supported by the vendor specific SPV_INTEL_inline_assembly extension,
if/when needed.
At the moment, however, SPV_INTEL_inline_assembly is the only
implemented way to bring LLVM IR inline assembly calls up to valid
SPIR-V instructions and also the default one. This means that inline
assembly calls will generate an error message of such extension is not
used to prevent LLVM-generated error messages at the final stages of
translation. When the SPV_INTEL_inline_assembly extension is mentioned
among supported, translation of inline assembly is intercepted by this
extension implementation on a pre-legalizer step, and this is a place
where support for a new inline assembly extension may be added if
needed.
This PR also extends support for register classes, improves type
inference during pre-legalizer pass, and fixes a minor bug with
asm-printing of string literals.
[1]
https://github.com/intel/llvm/blob/sycl/sycl/doc/design/spirv-extensions/SPV_INTEL_inline_assembly.asciidoc
Recognize `cl_khr_kernel_clock` builtins and translate them to
`OpReadClockKHR` instructions. The `Scope` operand is deduced from the
builtin function name.
spirv-val does not pass yet due to OpReadClockKHR only supporting the
valid scopes for Vulkan (Device and Subgroup, but not Workgroup), so
leave validation disabled with a TODO.
