[llvm] [SPIR-V] Add support for inline SPIR-V types (PR #125316)

[Cassandra Beckley via llvm-commits]

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@@ -104,10 +107,30 @@ static void emitUntypedInstrOperands(const MCInst &MI,
     emitOperand(Op, CB);
 }
 
+void SPIRVMCCodeEmitter::encodeUnknownType(const MCInst &MI,
+                                           SmallVectorImpl<char> &CB,
+                                           SmallVectorImpl<MCFixup> &Fixups,
+                                           const MCSubtargetInfo &STI) const {
+  // Encode the first 32 SPIR-V bytes with the number of args and the opcode.
+  const uint64_t OpCode = MI.getOperand(1).getImm();
+  const uint32_t NumWords = MI.getNumOperands();
+  const uint32_t FirstWord = (NumWords << 16) | OpCode;
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cassiebeckley wrote:

I've masked these values using `& 0xFF` to be consistent with the arbitrary integer encoding.

https://github.com/llvm/llvm-project/pull/125316