Conor McCarthy 6835e8176f vkd3d-shader/ir: Normalise signatures and input/output registers to the Shader Model 6 pattern.
In Shader Model 6 each signature element can span a range of register
indices, or 'rows', and system values do not share a register index with
non-system values. Inputs and outputs are referenced by element index
instead of register index. This patch merges multiple signature elements
into a single element under the following conditions:

- The register index in a load or store is specified dynamically by
  including a relative address parameter with a base register index. The
  dcl_index_range instruction is used to identify these.
- A register declaration is split across multiple elements which declare
  different components of the register.
- A patch constant function writes tessellation factors. These are an
  array in SPIR-V, but in SM 5.x each factor is declared as a separate
  register, and these are dynamically indexed by the fork/join instance
  id. Elimination of multiple fork/join phases converts the indices to
  constants, but merging the signature elements into a single arrayed
  element matches the SPIR-V output.

All references to input/output register indices are converted to element
indices. If a relative address is present, the element index is moved up
a slot so it cannot be confused with a constant offset. Existing code
only handles register index relative addressing for tessellation factors.
This patch adds generic support for it.
2023-05-24 22:00:29 +02:00
..
2018-06-27 22:43:49 +02:00