[llvm] [SPIRV] Add support for SPV_KHR_bit_instructions (PR #66215)

[Paulo Matos via llvm-commits]

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@@ -884,6 +902,12 @@ void addInstrRequirements(const MachineInstr &MI,
   default:
     break;
   }
+
+  // If we require capability Shader, then we can remove the requirement for
+  // the BitInstructions capability, since Shader is a superset capability
+  // of BitInstructions.
+  Reqs.removeCapabilityIf(SPIRV::Capability::Shader,
+                          SPIRV::Capability::BitInstructions);
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pmatos wrote:

yes, that's my reading. Shader is a superset so afaiu there's no point in having both. If something is required in Shader that's not in bit_instructions, then lets just drop bit_instructions and use Shader instead.

https://github.com/llvm/llvm-project/pull/66215