[DirectX] Shader Flags Analysis for DisableOptimizations

[bharadwajy]

This flag is set by dxc if -Od (or /Od) is specified on the command-line. This option is associated with -disable-llvm-optzns in dxc - see here.

Option -Od (or /Od) is supported by clang-dxc and is encapsulated via llvm.module.flags metadata (viz., dx.disable_optimizations) in the module.

An implementation to detect llvm module flag dx.disable_optimizations is complete and available in this changeset.

However, since dx.disable_optimizations is a non-standard DXIL named metadata replace its generation of metadata dx.disable_optimizations.

Set the shader flag DisableOptimizations based on the presence of entry function attribute optnone

AC
Add tests to check bit 0 of shader flags mask is set if O0, -Od (or /Od) is specified on command-line.

[bharadwajy]

This flag is set by dxc if -Od is specified on the command-line. This option is associated with -disable-llvm-optzns in dxc - see here.

Option -Od (or /Od) is supported by clang-dxc and is encapsulated via llvm.module.flags metadata (viz., dx.disable_optimizations) in the module.

An implementation to detect llvm module flag dx.disable_optimizations and set DisableOptimizations flag is complete and available in this changeset. A PR is planned to be created after the currently active PR that propagates shader flag mask from callees to callers is merged.

AC Add tests to check bit 0 of shader flags mask is set if -Od (or /Od) is specified on command-line.