Vulkan: Disable SPIR-V preprocessing when debugging
Vulkan: Disable SPIR-V preprocessing when debugging

Optimization passes are likely to damage debug information, and reorder instructions. We will likely never want to optimize shaders inside the driver when debugging.

SPIR-V tools currently has a number of issues consuming shaders that use the OpenCL.Debug.100 extension instructions which need to be fixed before these instructions can be passed to it. For now, just disable shader pre-processing when we are debugging.

Bug: b/145351270
Change-Id: I71827c2bb7cf34ecfd7e55b0ca8b3189e460b150
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/40130
Kokoro-Presubmit: kokoro <2ac7b1f3fa578934c95181d4272be0d3bca00121@google.com>
Tested-by: Ben Clayton <1f693eb7158dc33015048c09d6712f74dabddf79@google.com>
Reviewed-by: Nicolas Capens <51edc787c30f24c4904e8ffbb5523c3a9f7a451d@google.com>

bkaradzic/SwiftShader,bkaradzic/SwiftShader,bkaradzic/SwiftShader,google/swiftshader,google/swiftshader,bkaradzic/SwiftShader,bkaradzic/SwiftShader,google/swiftshader