[NFC][DecoderEmitter] Code cleanup in DecoderEmitter::emitTable

jurahul · jurahul · commit f7af184a5851 · 2025-09-14T16:43:41.000-07:00
Several code cleanup changes in code to emit decoder tables:
- Start comments on each line at a fixed column for readibility.
- Combine reperated code to decode and emit ULEB128 into a single
  function.
- Add helper `getDecoderOpName` to print decoder op.
- Print Filter/CheckField/predicate index values with those opcodes.
diff --git a/llvm/lib/Target/BPF/Disassembler/BPFDisassembler.cpp b/llvm/lib/Target/BPF/Disassembler/BPFDisassembler.cpp
@@ -26,6 +26,7 @@
 #include <cstdint>
 
 using namespace llvm;
+using namespace llvm::MCD;
 
 #define DEBUG_TYPE "bpf-disassembler"
 
diff --git a/llvm/lib/Target/CSKY/Disassembler/CSKYDisassembler.cpp b/llvm/lib/Target/CSKY/Disassembler/CSKYDisassembler.cpp
@@ -26,6 +26,7 @@
 #include "llvm/Support/Endian.h"
 
 using namespace llvm;
+using namespace llvm::MCD;
 
 #define DEBUG_TYPE "csky-disassembler"
 
diff --git a/llvm/lib/Target/Hexagon/Disassembler/HexagonDisassembler.cpp b/llvm/lib/Target/Hexagon/Disassembler/HexagonDisassembler.cpp
@@ -34,6 +34,7 @@
 #define DEBUG_TYPE "hexagon-disassembler"
 
 using namespace llvm;
+using namespace llvm::MCD;
 using namespace Hexagon;
 
 using DecodeStatus = MCDisassembler::DecodeStatus;
diff --git a/llvm/lib/Target/Lanai/Disassembler/LanaiDisassembler.cpp b/llvm/lib/Target/Lanai/Disassembler/LanaiDisassembler.cpp
@@ -28,6 +28,7 @@
 #define DEBUG_TYPE "lanai-disassembler"
 
 using namespace llvm;
+using namespace llvm::MCD;
 
 typedef MCDisassembler::DecodeStatus DecodeStatus;
 
diff --git a/llvm/lib/Target/LoongArch/Disassembler/LoongArchDisassembler.cpp b/llvm/lib/Target/LoongArch/Disassembler/LoongArchDisassembler.cpp
@@ -24,6 +24,7 @@
 #include "llvm/Support/Endian.h"
 
 using namespace llvm;
+using namespace llvm::MCD;
 
 #define DEBUG_TYPE "loongarch-disassembler"
 
diff --git a/llvm/lib/Target/PowerPC/Disassembler/PPCDisassembler.cpp b/llvm/lib/Target/PowerPC/Disassembler/PPCDisassembler.cpp
@@ -18,6 +18,7 @@
 #include "llvm/Support/Endian.h"
 
 using namespace llvm;
+using namespace llvm::MCD;
 
 DEFINE_PPC_REGCLASSES
 
diff --git a/llvm/lib/Target/SystemZ/Disassembler/SystemZDisassembler.cpp b/llvm/lib/Target/SystemZ/Disassembler/SystemZDisassembler.cpp
@@ -20,6 +20,7 @@
 #include <cstdint>
 
 using namespace llvm;
+using namespace llvm::MCD;
 
 #define DEBUG_TYPE "systemz-disassembler"
 
diff --git a/llvm/lib/Target/Xtensa/Disassembler/XtensaDisassembler.cpp b/llvm/lib/Target/Xtensa/Disassembler/XtensaDisassembler.cpp
@@ -25,6 +25,7 @@
 #include "llvm/Support/Endian.h"
 
 using namespace llvm;
+using namespace llvm::MCD;
 
 #define DEBUG_TYPE "Xtensa-disassembler"
 
diff --git a/llvm/test/TableGen/FixedLenDecoderEmitter/additional-encoding.td b/llvm/test/TableGen/FixedLenDecoderEmitter/additional-encoding.td
@@ -30,27 +30,27 @@ class I<dag out_ops, dag in_ops> : Instruction {
   let OutOperandList = out_ops;
 }
 
-// CHECK:      /* 0 */  MCD::OPC_ExtractField, 12, 4,  // Inst{15-12} ...
-// CHECK-NEXT: /* 3 */  MCD::OPC_FilterValueOrSkip, 0, 15, 0, // Skip to: 22
-// CHECK-NEXT: /* 7 */  MCD::OPC_Scope, 8, 0, // Skip to: 18
-// CHECK-NEXT: /* 10 */ MCD::OPC_CheckField, 6, 6, 0,
-// CHECK-NEXT: /* 14 */ MCD::OPC_Decode, {{[0-9]+}}, 2, 0, // Opcode: {{.*}}:NOP, DecodeIdx: 0
-// CHECK-NEXT: /* 18 */ MCD::OPC_TryDecode, {{[0-9]+}}, 2, 1,
-// CHECK-NEXT: /* 22 */ MCD::OPC_FilterValueOrSkip, 1, 15, 0, // Skip to: 41
-// CHECK-NEXT: /* 26 */ MCD::OPC_Scope, 8, 0, // Skip to: 37
-// CHECK-NEXT: /* 29 */ MCD::OPC_CheckField, 6, 6, 0,
-// CHECK-NEXT: /* 33 */ MCD::OPC_Decode, {{[0-9]+}}, 2, 0, // Opcode: {{.*}}:NOP, DecodeIdx: 0
-// CHECK-NEXT: /* 37 */ MCD::OPC_TryDecode, {{[0-9]+}}, 2, 1,
-// CHECK-NEXT: /* 41 */ MCD::OPC_FilterValueOrSkip, 2, 15, 0, // Skip to: 60
-// CHECK-NEXT: /* 45 */ MCD::OPC_Scope, 8, 0, // Skip to: 56
-// CHECK-NEXT: /* 48 */ MCD::OPC_CheckField, 6, 6, 0,
-// CHECK-NEXT: /* 52 */ MCD::OPC_Decode, {{[0-9]+}}, 2, 0, // Opcode: {{.*}}:NOP, DecodeIdx: 0
-// CHECK-NEXT: /* 56 */ MCD::OPC_TryDecode, {{[0-9]+}}, 2, 1,
-// CHECK-NEXT: /* 60 */ MCD::OPC_FilterValue, 3,
-// CHECK-NEXT: /* 62 */ MCD::OPC_Scope, 8, 0, // Skip to: 73
-// CHECK-NEXT: /* 65 */ MCD::OPC_CheckField, 6, 6, 0,
-// CHECK-NEXT: /* 69 */ MCD::OPC_Decode, {{[0-9]+}}, 2, 0, // Opcode: {{.*}}:NOP, DecodeIdx: 0
-// CHECK-NEXT: /* 73 */ MCD::OPC_TryDecode, {{[0-9]+}}, 2, 1,
+// CHECK:      /* 0 */  OPC_ExtractField, 12, 4,               // Field = Inst{15-12}
+// CHECK-NEXT: /* 3 */  OPC_FilterValueOrSkip, 0, 15, 0,       // if Field != 0x0 skip to 22
+// CHECK-NEXT: /* 7 */  OPC_Scope, 8, 0,                       // skip to 18
+// CHECK-NEXT: /* 10 */ OPC_CheckField, 6, 6, 0,               // if Inst{11-6} != 0x0
+// CHECK-NEXT: /* 14 */ OPC_Decode, {{[0-9]+}}, 2, 0,          // Opcode: {{.*}}:NOP, DecodeIdx: 0
+// CHECK-NEXT: /* 18 */ OPC_TryDecode, {{[0-9]+}}, 2, 1,       // Opcode: SHIFT0, DecodeIdx: 1
+// CHECK-NEXT: /* 22 */ OPC_FilterValueOrSkip, 1, 15, 0,       // if Field != 0x1 skip to 41
+// CHECK-NEXT: /* 26 */ OPC_Scope, 8, 0,                       // skip to 37
+// CHECK-NEXT: /* 29 */ OPC_CheckField, 6, 6, 0,               // if Inst{11-6} != 0x0
+// CHECK-NEXT: /* 33 */ OPC_Decode, {{[0-9]+}}, 2, 0,          // Opcode: {{.*}}:NOP, DecodeIdx: 0
+// CHECK-NEXT: /* 37 */ OPC_TryDecode, {{[0-9]+}}, 2, 1,       // Opcode: SHIFT1, DecodeIdx: 1
+// CHECK-NEXT: /* 41 */ OPC_FilterValueOrSkip, 2, 15, 0,       // if Field != 0x2 skip to 60
+// CHECK-NEXT: /* 45 */ OPC_Scope, 8, 0,                       // skip to 56
+// CHECK-NEXT: /* 48 */ OPC_CheckField, 6, 6, 0,               // if Inst{11-6} != 0x0
+// CHECK-NEXT: /* 52 */ OPC_Decode, {{[0-9]+}}, 2, 0,          // Opcode: {{.*}}:NOP, DecodeIdx: 0
+// CHECK-NEXT: /* 56 */ OPC_TryDecode, {{[0-9]+}}, 2, 1,       // Opcode: SHIFT2, DecodeIdx: 1
+// CHECK-NEXT: /* 60 */ OPC_FilterValue, 3,                    // if Field != 0x3
+// CHECK-NEXT: /* 62 */ OPC_Scope, 8, 0,                       // skip to 73
+// CHECK-NEXT: /* 65 */ OPC_CheckField, 6, 6, 0,               // if Inst{11-6} != 0x0
+// CHECK-NEXT: /* 69 */ OPC_Decode, {{[0-9]+}}, 2, 0,          // Opcode: {{.*}}:NOP, DecodeIdx: 0
+// CHECK-NEXT: /* 73 */ OPC_TryDecode, {{[0-9]+}}, 2, 1,       // Opcode: SHIFT3, DecodeIdx: 1
 
 
 class SHIFT<bits<2> opc> : I<(outs), (ins ShAmtOp:$shamt)>, EncSHIFT<opc>;
diff --git a/llvm/test/TableGen/FixedLenDecoderEmitter/big-filter.td b/llvm/test/TableGen/FixedLenDecoderEmitter/big-filter.td
@@ -12,13 +12,13 @@ class I : Instruction {
 // Check that a 64-bit filter with all bits set does not confuse DecoderEmitter.
 //
 // CHECK-LABEL: static const uint8_t DecoderTable128[34] = {
-// CHECK-NEXT:  /* 0 */  MCD::OPC_ExtractField, 0, 64,  // Inst{63-0} ...
-// CHECK-NEXT:  /* 3 */  MCD::OPC_FilterValueOrSkip, 1, 8, 0, // Skip to: 15
-// CHECK-NEXT:  /* 7 */  MCD::OPC_CheckField, 127, 1, 1,
-// CHECK-NEXT:  /* 11 */ MCD::OPC_Decode, {{[0-9]+}}, 2, 0, // Opcode: I2, DecodeIdx: 0
-// CHECK-NEXT:  /* 15 */ MCD::OPC_FilterValue, 255, 255, 255, 255, 255, 255, 255, 255, 255, 1,
-// CHECK-NEXT:  /* 26 */ MCD::OPC_CheckField, 127, 1, 0,
-// CHECK-NEXT:  /* 30 */ MCD::OPC_Decode, {{[0-9]+}}, 2, 0, // Opcode: I1, DecodeIdx: 0
+// CHECK-NEXT:  /* 0 */  OPC_ExtractField, 0, 64,        // Field = Inst{63-0}
+// CHECK-NEXT:  /* 3 */  OPC_FilterValueOrSkip, 1, 8, 0, // if Field != 0x1 skip to 15
+// CHECK-NEXT:  /* 7 */  OPC_CheckField, 127, 1, 1,      // if Inst{127} != 0x1
+// CHECK-NEXT:  /* 11 */ OPC_Decode, {{[0-9]+}}, 2, 0,   // Opcode: I2, DecodeIdx: 0
+// CHECK-NEXT:  /* 15 */ OPC_FilterValue, 255, 255, 255, 255, 255, 255, 255, 255, 255, 1, // if Field != 0xffffffffffffffff
+// CHECK-NEXT:  /* 26 */ OPC_CheckField, 127, 1, 0,      // if Inst{127} != 0x0
+// CHECK-NEXT:  /* 30 */ OPC_Decode, {{[0-9]+}}, 2, 0,   // Opcode: I1, DecodeIdx: 0
 // CHECK-NEXT:  };
 
 def I1 : I {
diff --git a/llvm/test/TableGen/FixedLenDecoderEmitter/var-len-conflict-1.td b/llvm/test/TableGen/FixedLenDecoderEmitter/var-len-conflict-1.td
@@ -18,19 +18,19 @@ class I : Instruction {
 // 00000001 ________  I16_1
 // 00000010 ________  I16_2
 
-// CHECK:      /* 0 */  MCD::OPC_Scope, 17, 0,               // Skip to: 20
-// CHECK-NEXT: /* 3 */  MCD::OPC_ExtractField, 0, 1,         // Inst{0} ...
-// CHECK-NEXT: /* 6 */  MCD::OPC_FilterValueOrSkip, 0, 4, 0, // Skip to: 14
-// CHECK-NEXT: /* 10 */ MCD::OPC_Decode, {{[0-9]+}}, 2, 0,   // Opcode: I8_0, DecodeIdx: 0
-// CHECK-NEXT: /* 14 */ MCD::OPC_FilterValue, 1,
-// CHECK-NEXT: /* 16 */ MCD::OPC_Decode, {{[0-9]+}}, 2, 0,   // Opcode: I8_1, DecodeIdx: 0
-// CHECK-NEXT: /* 20 */ MCD::OPC_ExtractField, 8, 8,         // Inst{15-8} ...
-// CHECK-NEXT: /* 23 */ MCD::OPC_FilterValueOrSkip, 0, 4, 0, // Skip to: 31
-// CHECK-NEXT: /* 27 */ MCD::OPC_Decode, {{[0-9]+}}, 2, 1,   // Opcode: I16_0, DecodeIdx: 1
-// CHECK-NEXT: /* 31 */ MCD::OPC_FilterValueOrSkip, 1, 4, 0, // Skip to: 39
-// CHECK-NEXT: /* 35 */ MCD::OPC_Decode, {{[0-9]+}}, 2, 1,   // Opcode: I16_1, DecodeIdx: 1
-// CHECK-NEXT: /* 39 */ MCD::OPC_FilterValue, 2,
-// CHECK-NEXT: /* 41 */ MCD::OPC_Decode, {{[0-9]+}}, 2, 1,   // Opcode: I16_2, DecodeIdx: 1
+// CHECK:      /* 0 */  OPC_Scope, 17, 0,               // skip to 20
+// CHECK-NEXT: /* 3 */  OPC_ExtractField, 0, 1,         // Field = Inst{0}
+// CHECK-NEXT: /* 6 */  OPC_FilterValueOrSkip, 0, 4, 0, // if Field != 0x0 skip to 14
+// CHECK-NEXT: /* 10 */ OPC_Decode, {{[0-9]+}}, 2, 0,   // Opcode: I8_0, DecodeIdx: 0
+// CHECK-NEXT: /* 14 */ OPC_FilterValue, 1,             // if Field != 0x1
+// CHECK-NEXT: /* 16 */ OPC_Decode, {{[0-9]+}}, 2, 0,   // Opcode: I8_1, DecodeIdx: 0
+// CHECK-NEXT: /* 20 */ OPC_ExtractField, 8, 8,         // Field = Inst{15-8}
+// CHECK-NEXT: /* 23 */ OPC_FilterValueOrSkip, 0, 4, 0, // if Field != 0x0 skip to 31
+// CHECK-NEXT: /* 27 */ OPC_Decode, {{[0-9]+}}, 2, 1,   // Opcode: I16_0, DecodeIdx: 1
+// CHECK-NEXT: /* 31 */ OPC_FilterValueOrSkip, 1, 4, 0, // if Field != 0x1 skip to 39
+// CHECK-NEXT: /* 35 */ OPC_Decode, {{[0-9]+}}, 2, 1,   // Opcode: I16_1, DecodeIdx: 1
+// CHECK-NEXT: /* 39 */ OPC_FilterValue, 2,             // if Field != 0x2
+// CHECK-NEXT: /* 41 */ OPC_Decode, {{[0-9]+}}, 2, 1,   // Opcode: I16_2, DecodeIdx: 1
 
 def I8_0  : I { dag Inst = (descend (operand "$op", 7), 0b0); }
 def I8_1  : I { dag Inst = (descend (operand "$op", 7), 0b1); }
diff --git a/llvm/test/TableGen/VarLenDecoder.td b/llvm/test/TableGen/VarLenDecoder.td
@@ -53,18 +53,18 @@ def FOO32 : MyVarInst<MemOp32> {
 // CHECK-NEXT: 43,
 // CHECK-NEXT: };
 
-// CHECK-SMALL:      /* 0 */       MCD::OPC_ExtractField, 3, 5,  // Inst{7-3} ...
-// CHECK-SMALL-NEXT: /* 3 */       MCD::OPC_FilterValueOrSkip, 8, 4, 0, // Skip to: 11
-// CHECK-SMALL-NEXT: /* 7 */       MCD::OPC_Decode, {{[0-9]+}}, {{[0-9]+}}, 0, // Opcode: FOO16
-// CHECK-SMALL-NEXT: /* 11 */      MCD::OPC_FilterValue, 9,
-// CHECK-SMALL-NEXT: /* 13 */      MCD::OPC_Decode, {{[0-9]+}}, {{[0-9]+}}, 1, // Opcode: FOO32
+// CHECK-SMALL:      /* 0 */       OPC_ExtractField, 3, 5,                // Field = Inst{7-3}
+// CHECK-SMALL-NEXT: /* 3 */       OPC_FilterValueOrSkip, 8, 4, 0,        // if Field != 0x8 skip to 11
+// CHECK-SMALL-NEXT: /* 7 */       OPC_Decode, {{[0-9]+}}, {{[0-9]+}}, 0, // Opcode: FOO16
+// CHECK-SMALL-NEXT: /* 11 */      OPC_FilterValue, 9,                    // if Field != 0x9 pop scope
+// CHECK-SMALL-NEXT: /* 13 */      OPC_Decode, {{[0-9]+}}, {{[0-9]+}}, 1, // Opcode: FOO32
 // CHECK-SMALL-NEXT: };
 
-// CHECK-LARGE:      /* 0 */       MCD::OPC_ExtractField, 3, 5,  // Inst{7-3} ...
-// CHECK-LARGE-NEXT: /* 3 */       MCD::OPC_FilterValueOrSkip, 8, 4, 0, 0, // Skip to: 12
-// CHECK-LARGE-NEXT: /* 8 */       MCD::OPC_Decode, {{[0-9]+}}, {{[0-9]+}}, 0, // Opcode: FOO16
-// CHECK-LARGE-NEXT: /* 12 */      MCD::OPC_FilterValue, 9,
-// CHECK-LARGE-NEXT: /* 14 */      MCD::OPC_Decode, {{[0-9]+}}, {{[0-9]+}}, 1, // Opcode: FOO32
+// CHECK-LARGE:      /* 0 */       OPC_ExtractField, 3, 5,                // Field = Inst{7-3}
+// CHECK-LARGE-NEXT: /* 3 */       OPC_FilterValueOrSkip, 8, 4, 0, 0,     // if Field != 0x8 skip to 12
+// CHECK-LARGE-NEXT: /* 8 */       OPC_Decode, {{[0-9]+}}, {{[0-9]+}}, 0, // Opcode: FOO16
+// CHECK-LARGE-NEXT: /* 12 */      OPC_FilterValue, 9,                    // if Field != 0x9 pop scope
+// CHECK-LARGE-NEXT: /* 14 */      OPC_Decode, {{[0-9]+}}, {{[0-9]+}}, 1, // Opcode: FOO32
 // CHECK-LARGE-NEXT: };
 
 // CHECK:      case 0:
@@ -86,12 +86,12 @@ def FOO32 : MyVarInst<MemOp32> {
 // CHECK-NEXT: MI.addOperand(MCOperand::createImm(tmp));
 // CHECK-NEXT: return S;
 
-// CHECK-LABEL: case MCD::OPC_ExtractField: {
+// CHECK-LABEL: case OPC_ExtractField: {
 // CHECK: makeUp(insn, Start + Len);
 
-// CHECK-LABEL: case MCD::OPC_CheckField: {
+// CHECK-LABEL: case OPC_CheckField: {
 // CHECK: makeUp(insn, Start + Len);
 
-// CHECK-LABEL: case MCD::OPC_Decode: {
+// CHECK-LABEL: case OPC_Decode: {
 // CHECK: Len = InstrLenTable[Opc];
 // CHECK-NEXT: makeUp(insn, Len);
diff --git a/llvm/test/TableGen/trydecode-emission.td b/llvm/test/TableGen/trydecode-emission.td
@@ -34,11 +34,11 @@ def InstB : TestInstruction {
   let hasCompleteDecoder = 0;
 }
 
-// CHECK:      /* 0 */       MCD::OPC_CheckField, 4, 4, 0,
-// CHECK-NEXT: /* 4 */       MCD::OPC_Scope, 8, 0, // Skip to: 15
-// CHECK-NEXT: /* 7 */       MCD::OPC_CheckField, 2, 2, 0,
-// CHECK-NEXT: /* 11 */      MCD::OPC_TryDecode, {{[0-9]+}}, {{[0-9]+}}, 0,
-// CHECK-NEXT: /* 15 */      MCD::OPC_Decode, {{[0-9]+}}, {{[0-9]+}}, 1, // Opcode: InstA, DecodeIdx: 1
+// CHECK:      /* 0 */       OPC_CheckField, 4, 4, 0,                   // if Inst{7-4} != 0x0
+// CHECK-NEXT: /* 4 */       OPC_Scope, 8, 0,                           // skip to 15
+// CHECK-NEXT: /* 7 */       OPC_CheckField, 2, 2, 0,                   // if Inst{3-2} != 0x0
+// CHECK-NEXT: /* 11 */      OPC_TryDecode, {{[0-9]+}}, {{[0-9]+}}, 0,  // Opcode: InstB, DecodeIdx: 0
+// CHECK-NEXT: /* 15 */      OPC_Decode, {{[0-9]+}}, {{[0-9]+}}, 1,     // Opcode: InstA, DecodeIdx: 1
 // CHECK-NEXT: };
 
 // CHECK: if (!Check(S, DecodeInstB(MI, insn, Address, Decoder))) { DecodeComplete = false; return MCDisassembler::Fail; }
@@ -47,11 +47,11 @@ def InstB : TestInstruction {
 // CHECK-NEXT:  NumToSkip |= (*Ptr++) << 8;
 // CHECK-NEXT:  return NumToSkip;
 
-// CHECK-LARGE:      /* 0 */       MCD::OPC_CheckField, 4, 4, 0,
-// CHECK-LARGE-NEXT: /* 4 */       MCD::OPC_Scope, 8, 0, 0, // Skip to: 16
-// CHECK-LARGE-NEXT: /* 8 */       MCD::OPC_CheckField, 2, 2, 0,
-// CHECK-LARGE-NEXT: /* 12 */      MCD::OPC_TryDecode, {{[0-9]+}}, {{[0-9]+}}, 0,
-// CHECK-LARGE-NEXT: /* 16 */      MCD::OPC_Decode, {{[0-9]+}}, {{[0-9]+}}, 1, // Opcode: InstA, DecodeIdx: 1
+// CHECK-LARGE:      /* 0 */       OPC_CheckField, 4, 4, 0,                  // if Inst{7-4} != 0x0
+// CHECK-LARGE-NEXT: /* 4 */       OPC_Scope, 8, 0, 0,                       // skip to 16
+// CHECK-LARGE-NEXT: /* 8 */       OPC_CheckField, 2, 2, 0,                  // if Inst{3-2} != 0x0
+// CHECK-LARGE-NEXT: /* 12 */      OPC_TryDecode, {{[0-9]+}}, {{[0-9]+}}, 0, // Opcode: InstB, DecodeIdx: 0
+// CHECK-LARGE-NEXT: /* 16 */      OPC_Decode, {{[0-9]+}}, {{[0-9]+}}, 1,    // Opcode: InstA, DecodeIdx: 1
 // CHECK-LARGE-NEXT: };
 
 // CHECK-LARGE: if (!Check(S, DecodeInstB(MI, insn, Address, Decoder))) { DecodeComplete = false; return MCDisassembler::Fail; }
diff --git a/llvm/test/TableGen/trydecode-emission2.td b/llvm/test/TableGen/trydecode-emission2.td
@@ -31,24 +31,24 @@ def InstB : TestInstruction {
   let hasCompleteDecoder = 0;
 }
 
-// CHECK:      /* 0 */       MCD::OPC_CheckField, 2, 1, 0,
-// CHECK-NEXT: /* 4 */       MCD::OPC_CheckField, 5, 3, 0,
-// CHECK-NEXT: /* 8 */       MCD::OPC_Scope, 8, 0, // Skip to: 19
-// CHECK-NEXT: /* 11 */      MCD::OPC_CheckField, 0, 2, 3,
-// CHECK-NEXT: /* 15 */      MCD::OPC_TryDecode, {{[0-9]+}}, {{[0-9]+}}, 0,
-// CHECK-NEXT: /* 19 */      MCD::OPC_CheckField, 3, 2, 0,
-// CHECK-NEXT: /* 23 */      MCD::OPC_TryDecode, {{[0-9]+}}, {{[0-9]+}}, 1,
+// CHECK:      /* 0 */       OPC_CheckField, 2, 1, 0,
+// CHECK-NEXT: /* 4 */       OPC_CheckField, 5, 3, 0,
+// CHECK-NEXT: /* 8 */       OPC_Scope, 8, 0, // skip to 19
+// CHECK-NEXT: /* 11 */      OPC_CheckField, 0, 2, 3,
+// CHECK-NEXT: /* 15 */      OPC_TryDecode, {{[0-9]+}}, {{[0-9]+}}, 0,
+// CHECK-NEXT: /* 19 */      OPC_CheckField, 3, 2, 0,
+// CHECK-NEXT: /* 23 */      OPC_TryDecode, {{[0-9]+}}, {{[0-9]+}}, 1,
 
 // CHECK: if (!Check(S, DecodeInstB(MI, insn, Address, Decoder))) { DecodeComplete = false; return MCDisassembler::Fail; }
 // CHECK: if (!Check(S, DecodeInstA(MI, insn, Address, Decoder))) { DecodeComplete = false; return MCDisassembler::Fail; }
 
-// CHECK-LARGE:      /* 0 */       MCD::OPC_CheckField, 2, 1, 0,
-// CHECK-LARGE-NEXT: /* 4 */       MCD::OPC_CheckField, 5, 3, 0,
-// CHECK-LARGE-NEXT: /* 8 */       MCD::OPC_Scope, 8, 0, 0, // Skip to: 20
-// CHECK-LARGE-NEXT: /* 12 */      MCD::OPC_CheckField, 0, 2, 3,
-// CHECK-LARGE-NEXT: /* 16 */      MCD::OPC_TryDecode, {{[0-9]+}}, {{[0-9]+}}, 0,
-// CHECK-LARGE-NEXT: /* 20 */      MCD::OPC_CheckField, 3, 2, 0,
-// CHECK-LARGE-NEXT: /* 24 */      MCD::OPC_TryDecode, {{[0-9]+}}, {{[0-9]+}}, 1,
+// CHECK-LARGE:      /* 0 */       OPC_CheckField, 2, 1, 0,
+// CHECK-LARGE-NEXT: /* 4 */       OPC_CheckField, 5, 3, 0,
+// CHECK-LARGE-NEXT: /* 8 */       OPC_Scope, 8, 0, 0, // skip to 20
+// CHECK-LARGE-NEXT: /* 12 */      OPC_CheckField, 0, 2, 3,
+// CHECK-LARGE-NEXT: /* 16 */      OPC_TryDecode, {{[0-9]+}}, {{[0-9]+}}, 0,
+// CHECK-LARGE-NEXT: /* 20 */      OPC_CheckField, 3, 2, 0,
+// CHECK-LARGE-NEXT: /* 24 */      OPC_TryDecode, {{[0-9]+}}, {{[0-9]+}}, 1,
 // CHECK-LARGE-NEXT: };
 
 // CHECK-LARGE: if (!Check(S, DecodeInstB(MI, insn, Address, Decoder))) { DecodeComplete = false; return MCDisassembler::Fail; }
diff --git a/llvm/test/TableGen/trydecode-emission3.td b/llvm/test/TableGen/trydecode-emission3.td
@@ -35,20 +35,20 @@ def InstB : TestInstruction {
   let AsmString = "InstB";
 }
 
-// CHECK:      /* 0 */       MCD::OPC_CheckField, 4, 4, 0,
-// CHECK-NEXT: /* 4 */       MCD::OPC_Scope, 8, 0, // Skip to: 15
-// CHECK-NEXT: /* 7 */       MCD::OPC_CheckField, 2, 2, 0,
-// CHECK-NEXT: /* 11 */      MCD::OPC_TryDecode, {{[0-9]+}}, {{[0-9]+}}, 0,
-// CHECK-NEXT: /* 15 */      MCD::OPC_Decode, {{[0-9]+}}, {{[0-9]+}}, 1, // Opcode: InstA, DecodeIdx: 1
+// CHECK:      /* 0 */       OPC_CheckField, 4, 4, 0,
+// CHECK-NEXT: /* 4 */       OPC_Scope, 8, 0, // skip to 15
+// CHECK-NEXT: /* 7 */       OPC_CheckField, 2, 2, 0,
+// CHECK-NEXT: /* 11 */      OPC_TryDecode, {{[0-9]+}}, {{[0-9]+}}, 0,
+// CHECK-NEXT: /* 15 */      OPC_Decode, {{[0-9]+}}, {{[0-9]+}}, 1, // Opcode: InstA, DecodeIdx: 1
 // CHECK-NEXT: };
 
 // CHECK: if (!Check(S, DecodeInstBOp(MI, tmp, Address, Decoder))) { DecodeComplete = false; return MCDisassembler::Fail; }
 
-// CHECK-LARGE:      /* 0 */       MCD::OPC_CheckField, 4, 4, 0,
-// CHECK-LARGE-NEXT: /* 4 */       MCD::OPC_Scope, 8, 0, 0, // Skip to: 16
-// CHECK-LARGE-NEXT: /* 8 */       MCD::OPC_CheckField, 2, 2, 0,
-// CHECK-LARGE-NEXT: /* 12 */      MCD::OPC_TryDecode, {{[0-9]+}}, {{[0-9]+}}, 0,
-// CHECK-LARGE-NEXT: /* 16 */      MCD::OPC_Decode, {{[0-9]+}}, {{[0-9]+}}, 1, // Opcode: InstA, DecodeIdx: 1
+// CHECK-LARGE:      /* 0 */       OPC_CheckField, 4, 4, 0,
+// CHECK-LARGE-NEXT: /* 4 */       OPC_Scope, 8, 0, 0, // skip to 16
+// CHECK-LARGE-NEXT: /* 8 */       OPC_CheckField, 2, 2, 0,
+// CHECK-LARGE-NEXT: /* 12 */      OPC_TryDecode, {{[0-9]+}}, {{[0-9]+}}, 0,
+// CHECK-LARGE-NEXT: /* 16 */      OPC_Decode, {{[0-9]+}}, {{[0-9]+}}, 1, // Opcode: InstA, DecodeIdx: 1
 // CHECK-LARGE-NEXT: };
 
 // CHECK-LARGE: if (!Check(S, DecodeInstBOp(MI, tmp, Address, Decoder))) { DecodeComplete = false; return MCDisassembler::Fail; }
diff --git a/llvm/test/TableGen/trydecode-emission4.td b/llvm/test/TableGen/trydecode-emission4.td
@@ -33,21 +33,21 @@ def InstB : TestInstruction {
   let hasCompleteDecoder = 0;
 }
 
-// CHECK:      /* 0 */       MCD::OPC_CheckField, 250, 3, 4, 0,
-// CHECK-NEXT: /* 5 */       MCD::OPC_Scope, 9, 0, // Skip to: 17
-// CHECK-NEXT: /* 8 */       MCD::OPC_CheckField, 248, 3, 2, 0,
-// CHECK-NEXT: /* 13 */      MCD::OPC_TryDecode, {{[0-9]+}}, {{[0-9]+}}, 0,
-// CHECK-NEXT: /* 17 */      MCD::OPC_Decode, {{[0-9]+}}, {{[0-9]+}}, 1, // Opcode: InstA, DecodeIdx: 1
+// CHECK:      /* 0 */       OPC_CheckField, 250, 3, 4, 0,
+// CHECK-NEXT: /* 5 */       OPC_Scope, 9, 0, // skip to 17
+// CHECK-NEXT: /* 8 */       OPC_CheckField, 248, 3, 2, 0,
+// CHECK-NEXT: /* 13 */      OPC_TryDecode, {{[0-9]+}}, {{[0-9]+}}, 0,
+// CHECK-NEXT: /* 17 */      OPC_Decode, {{[0-9]+}}, {{[0-9]+}}, 1, // Opcode: InstA, DecodeIdx: 1
 // CHECK-NEXT: };
 
 // CHECK: if (!Check(S, DecodeInstB(MI, insn, Address, Decoder))) { DecodeComplete = false; return MCDisassembler::Fail; }
 
 
-// CHECK-LARGE:      /* 0 */       MCD::OPC_CheckField, 250, 3, 4, 0,
-// CHECK-LARGE-NEXT: /* 5 */       MCD::OPC_Scope, 9, 0, 0, // Skip to: 18
-// CHECK-LARGE-NEXT: /* 9 */       MCD::OPC_CheckField, 248, 3, 2, 0,
-// CHECK-LARGE-NEXT: /* 14 */      MCD::OPC_TryDecode, {{[0-9]+}}, {{[0-9]+}}, 0,
-// CHECK-LARGE-NEXT: /* 18 */      MCD::OPC_Decode, {{[0-9]+}}, {{[0-9]+}}, 1, // Opcode: InstA, DecodeIdx: 1
+// CHECK-LARGE:      /* 0 */       OPC_CheckField, 250, 3, 4, 0,
+// CHECK-LARGE-NEXT: /* 5 */       OPC_Scope, 9, 0, 0, // skip to 18
+// CHECK-LARGE-NEXT: /* 9 */       OPC_CheckField, 248, 3, 2, 0,
+// CHECK-LARGE-NEXT: /* 14 */      OPC_TryDecode, {{[0-9]+}}, {{[0-9]+}}, 0,
+// CHECK-LARGE-NEXT: /* 18 */      OPC_Decode, {{[0-9]+}}, {{[0-9]+}}, 1, // Opcode: InstA, DecodeIdx: 1
 // CHECK-LARGE-NEXT: };
 
 // CHECK-LARGE: if (!Check(S, DecodeInstB(MI, insn, Address, Decoder))) { DecodeComplete = false; return MCDisassembler::Fail; }
diff --git a/llvm/utils/TableGen/DecoderEmitter.cpp b/llvm/utils/TableGen/DecoderEmitter.cpp
