Add NonSemantic.Shader.DebugInfo.100 options for Nvidia Nsight and/or RenderDoc source debugging

[DannyArends]

What

Adds two compile options that make shaderc emit NonSemantic.Shader.DebugInfo.100, equivalent to glslang's -gV / -gVS:

• shaderc_compile_options_set_generate_nonsemantic_debug_info, equivalent to -gV
• shaderc_compile_options_set_generate_nonsemantic_debug_source, equivalent to -gVS

Additionally, I have wired up matching CompileOptions::SetGenerateNonSemanticDebugInfo() / SetGenerateNonSemanticDebugSource() in the C++ wrapper.

Why

set_generate_debug_info only emits OpLine/OpSource (glslang -g). Tools like NVIDIA Nsight Graphics need NonSemantic.Shader.DebugInfo.100 for function- and call-site-level source correlation (Flame Graph, Top-Down/Bottom-Up Calls). shaderc had no way to request it (see #1391), so callers had to drop to glslang or dxc directly. The pull requests makes these new flag independent from generate_debug_info so plain -g stays available as a fallback for shaders that fail to compile withNonSemantic info enabled.

Usage: a Nsight-ready build

    shaderc_compile_options_t options = shaderc_compile_options_initialize();
    shaderc_compile_options_set_generate_debug_info(options);               // -g:   OpLine/OpSource
    shaderc_compile_options_set_generate_nonsemantic_debug_source(options); // -gVS: NonSemantic + source
    shaderc_compile_options_set_optimization_level(options, shaderc_optimization_level_zero);

-g provides the line table, -gVS provides the call graph; Nsight uses both. Optimization must stay at zero. The size/performance passes can mangle or strip NonSemantic info even with the strip-guards in place.

Notes

• Build against glslang >= 15.0.0; earlier versions point every DebugFunction at the same file, corrupting name/line correlation.
• Some shaders fail to compile with NonSemantic enabled; since the new flags are independent of -g, this is now a non-issue since builds need to opt in.

[google-cla]

Thanks for your pull request! It looks like this may be your first contribution to a Google open source project. Before we can look at your pull request, you'll need to sign a Contributor License Agreement (CLA).

View this failed invocation of the CLA check for more information.

For the most up to date status, view the checks section at the bottom of the pull request.

[DannyArends]

Update: I have signed the CLA, let me know if anything else is needed from my side.

[dneto0]

The function name reads weirdly.

I'd prefer: RemoveStripDebugInfoPass.

Not a huge issue though.

[dneto0]

This change should also include a command-line option on glslc, and please at least one unit test for each option, and glslc-based tests.

[DannyArends]

Thanks for the review @dneto0.

I've pushed changes addressing all points raised:

• Renamed UnstripDebugInfoPasses to RemoveStripDebugInfoPass.
• Added -gV and -gVS to glslc, with matching --help entries (updated the HelpParameters test output to match).
• Added unit tests for each option at both the C and C++ API layers, asserting that NonSemantic.Shader.DebugInfo.100 is imported in the disassembly.
• Added glslc-based tests: OptionGV checks the import, and OptionGVS checks the import plus a source-bearing DebugSource.

A minor note on the OptionGVS test: both -gV and -gVS emit a DebugSource. The only structural difference is that -gVS adds a second operand (the embedded-source OpString). The test asserts two operands with an ID-independent regex (DebugSource %\w+ %\w+) rather than just matching on the source substring (which on its own isn't a reliable discriminator). Happy to adjust if you'd prefer a different approach.

I ran ctest --output-on-failure and everything passes locally.