The commit introduces support for fundamental DI instruction. Metadata
handlers required for this instruction is stored inside debug records
(https://llvm.org/docs/SourceLevelDebugging.html) parts of the module
which rises the necessity of it's traversal.
The declaration in SPIRV.h had this returning a `MachineFunctionPass *`,
but the implementation returned a `FunctionPass *`. This showed up as a
build error on windows, but it was clearly a mistake regardless.
I also updated the pass to include SPIRV.h rather than using its own
declarations for pass initialization, as this results in better errors
for this kind of typo.
Fixes a build break after #97558
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.
