[HLSL] Validate that updateCounter is only either incremented or decremented and not both

[hekota]

RWStructuredBuffer has IncrementCounter and DecrementCounter. Only one of these methods can ever be called on any given RWStructuredBuffer instance - the buffer counter can only be incremented or decremented but not both.

DXC validation rule: Instr.OnlyOneAllocConsume

AC:

• Test case rejects IR that calls updateCounter with both a positive and negative number

Design:

• Add a new late stage DXIL only pass to llvm/lib/Target/DirectX/DirectXIRPasses that errors when updateCounter is incremented and decremented on the same resource, this pass should be small/focused in order to avoid becoming a kitchen sync
• Register the pass in Target/DirectX/DirectXTargetMachine.cpp before DXILOpLowering
• Walk the module searching for updateCounter calls. For each updateCounter call
  • extract the resource handle, and the current inc/dec value
  • resolve the handle into binding info
  • check if the key is in a pass global map
    • if yes: error if map value != current inc/dec value
    • if no: insert key into map with current inc/dev value

Notes:

• SPIR-V doesn't have this restriction so the validation isn't added there

[V-FEXrt]

Qs:

• Can this be done at LLVM IR or does the work need to be duplicated for DXIL and SPRIV
  • A: This validation is only needed for DXIL, nothing is needed for SPRIV
• Is there a "Passes" template or should I just work from something like MachinePostDominatorTreeAnalysis
• Should this be a fully new pass or can it be stuffed into something existing like DXILResourceTypeAnalysis

[V-FEXrt]

Expected error: https://godbolt.org/z/ofWfTGG4P