[llvm] [LLVM][MC] Introduce `OrFail` variants of MCD ops (PR #138614)

[Sergei Barannikov via llvm-commits]

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@@ -10,24 +10,29 @@
 #ifndef LLVM_MC_MCDECODEROPS_H
 #define LLVM_MC_MCDECODEROPS_H
 
-namespace llvm {
+namespace llvm::MCD {
 
-namespace MCD {
 // Disassembler state machine opcodes.
+// nts_t is either uint16_t or uint24_t based on whether large decoder table is
+// enabled.
 enum DecoderOps {
-  OPC_ExtractField = 1, // OPC_ExtractField(uleb128 Start, uint8_t Len)
-  OPC_FilterValue,      // OPC_FilterValue(uleb128 Val, uint16_t NumToSkip)
-  OPC_CheckField,       // OPC_CheckField(uleb128 Start, uint8_t Len,
-                        //                uleb128 Val, uint16_t NumToSkip)
-  OPC_CheckPredicate,   // OPC_CheckPredicate(uleb128 PIdx, uint16_t NumToSkip)
-  OPC_Decode,           // OPC_Decode(uleb128 Opcode, uleb128 DIdx)
-  OPC_TryDecode,        // OPC_TryDecode(uleb128 Opcode, uleb128 DIdx,
-                        //               uint16_t NumToSkip)
-  OPC_SoftFail,         // OPC_SoftFail(uleb128 PMask, uleb128 NMask)
-  OPC_Fail              // OPC_Fail()
+  OPC_ExtractField = 1,     // OPC_ExtractField(uleb128 Start, uint8_t Len)
+  OPC_FilterValue,          // OPC_FilterValue(uleb128 Val, nts_t NumToSkip)
+  OPC_FilterValueOrFail,    // OPC_FilterValueOrFail(uleb128 Val)
+  OPC_CheckField,           // OPC_CheckField(uleb128 Start, uint8_t Len,
+                            //                uleb128 Val, nts_t NumToSkip)
+  OPC_CheckFieldOrFail,     // OPC_CheckFieldOrFail(uleb128 Start, uint8_t Len,
+                            //                uleb128 Val)
+  OPC_CheckPredicate,       // OPC_CheckPredicate(uleb128 PIdx, nts_t NumToSkip)
+  OPC_CheckPredicateOrFail, // OPC_CheckPredicateOrFail(uleb128 PIdx)
+  OPC_Decode,               // OPC_Decode(uleb128 Opcode, uleb128 DIdx)
+  OPC_TryDecode,            // OPC_TryDecode(uleb128 Opcode, uleb128 DIdx,
+                            //               nts_t NumToSkip)
+  OPC_TryDecodeOrFail,      // OPC_TryDecodeOrFail(uleb128 Opcode, uleb128 DIdx)
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s-barannikov wrote:

Should this one be `OPC_DecodeOrFail`?

https://github.com/llvm/llvm-project/pull/138614