If an application compiles the same shader multiple times, we should reuse
an already existing DxvkShaderModule instead of creating a new one. This
helps keep the number of DxvkGraphicsPipeline objects low in games such
as Rise of the Tomb Raider.
SPIR-V tools did not turn out to be useful, but increased the
binary size by a significant amount and caused build problems.
- spirv-opt: Far too slow for the intended purpose, and Nvidia
specific shader issues have been reported and fixed.
- spirv-val: Not much value in practice since shaders can be
written to a directory and validated manually.
When using DXVK_LOG_LEVEL=debug, the graphics pipeline manager now
prints the names of the shaders used by the pipeline. This shall
help debug driver crashes in vkCreate*Pipelines.
