[WebAssembly] Remove exnref and br_on_exn

[aheejin]

Summary

This removes exnref type and br_on_exn instruction. This is
effectively NFC because most uses of these were already removed in the
previous CLs.

[aheejin]

Revert clang-format for MachineValueType.h

[tlively]

Nice!

lld/wasm/WriterUtils.cpp

std::string toString(ValType type) {
   case ValType::I64:
     return "i64";
   case ValType::F32:
     return "f32";
   case ValType::F64:
     return "f64";
   case ValType::V128:
     return "v128";
-  case ValType::EXNREF:
-    return "exnref";
   case ValType::FUNCREF:
     return "funcref";
   case ValType::EXTERNREF:
     return "externref";
   }
   llvm_unreachable("Invalid wasm::ValType");
 }
 

llvm/include/llvm/BinaryFormat/Wasm.h

 // Type immediate encodings used in various contexts.
 enum : unsigned {
   WASM_TYPE_I32 = 0x7F,
   WASM_TYPE_I64 = 0x7E,
   WASM_TYPE_F32 = 0x7D,
   WASM_TYPE_F64 = 0x7C,
   WASM_TYPE_V128 = 0x7B,
   WASM_TYPE_FUNCREF = 0x70,
-  WASM_TYPE_EXNREF = 0x68,
   WASM_TYPE_EXTERNREF = 0x6F,
   WASM_TYPE_FUNC = 0x60,
   WASM_TYPE_NORESULT = 0x40, // for blocks with no result values
 };
 
 // Kinds of externals (for imports and exports).
 enum : unsigned {
   WASM_EXTERNAL_FUNCTION = 0x0,

 
 // Subset of types that a value can have
 enum class ValType {
   I32 = WASM_TYPE_I32,
   I64 = WASM_TYPE_I64,
   F32 = WASM_TYPE_F32,
   F64 = WASM_TYPE_F64,
   V128 = WASM_TYPE_V128,
-  EXNREF = WASM_TYPE_EXNREF,
   FUNCREF = WASM_TYPE_FUNCREF,
   EXTERNREF = WASM_TYPE_EXTERNREF,
 };
 
 struct WasmSignature {
   SmallVector<ValType, 1> Returns;
   SmallVector<ValType, 4> Params;
   // Support empty and tombstone instances, needed by DenseMap.

llvm/include/llvm/CodeGen/ValueTypes.td

 def nxv2f64  : ValueType<128, 154>; // n x  2 x f64 vector value
 def nxv4f64  : ValueType<256, 155>; // n x  4 x f64 vector value
 def nxv8f64  : ValueType<512, 156>; // n x  8 x f64 vector value
 
 def x86mmx : ValueType<64 , 157>;   // X86 MMX value
 def FlagVT : ValueType<0  , 158>;   // Pre-RA sched glue
 def isVoid : ValueType<0  , 159>;   // Produces no value
 def untyped: ValueType<8  , 160>;   // Produces an untyped value
-def exnref : ValueType<0  , 161>;   // WebAssembly's exnref type
-def funcref : ValueType<0  , 162>;   // WebAssembly's funcref type
-def externref : ValueType<0  , 163>;   // WebAssembly's externref type
-def x86amx : ValueType<8192, 164>;   // X86 AMX value
+def funcref : ValueType<0  , 161>;   // WebAssembly's funcref type
+def externref : ValueType<0  , 162>;   // WebAssembly's externref type
+def x86amx : ValueType<8192, 163>;   // X86 AMX value
 
 
 def token  : ValueType<0  , 248>;   // TokenTy
 def MetadataVT: ValueType<0, 249>;  // Metadata
 
 // Pseudo valuetype mapped to the current pointer size to any address space.
 // Should only be used in TableGen.
 def iPTRAny   : ValueType<0, 250>;

llvm/include/llvm/Support/MachineValueType.h

 //===- Support/MachineValueType.h - Machine-Level types ---------*- C++ -*-===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 //
 // This file defines the set of machine-level target independent types which
namespace llvm {
   public:
     enum SimpleValueType : uint8_t {
       // Simple value types that aren't explicitly part of this enumeration
       // are considered extended value types.
       INVALID_SIMPLE_VALUE_TYPE = 0,
 
       // If you change this numbering, you must change the values in
       // ValueTypes.td as well!
       Other          =   1,   // This is a non-standard value
       i1             =   2,   // This is a 1 bit integer value
       i8             =   3,   // This is an 8 bit integer value
       i16            =   4,   // This is a 16 bit integer value
       i32            =   5,   // This is a 32 bit integer value
       i64            =   6,   // This is a 64 bit integer value
       i128           =   7,   // This is a 128 bit integer value
 
       FIRST_INTEGER_VALUETYPE = i1,
       LAST_INTEGER_VALUETYPE  = i128,
 
       bf16           =   8,   // This is a 16 bit brain floating point value
       f16            =   9,   // This is a 16 bit floating point value
       f32            =  10,   // This is a 32 bit floating point value
       f64            =  11,   // This is a 64 bit floating point value
       f80            =  12,   // This is a 80 bit floating point value
       f128           =  13,   // This is a 128 bit floating point value
       ppcf128        =  14,   // This is a PPC 128-bit floating point value
 
       FIRST_FP_VALUETYPE = bf16,
       LAST_FP_VALUETYPE  = ppcf128,
 
       v1i1           =  15,   //    1 x i1
       v2i1           =  16,   //    2 x i1
       v4i1           =  17,   //    4 x i1
       v8i1           =  18,   //    8 x i1
       v16i1          =  19,   //   16 x i1
       v32i1          =  20,   //   32 x i1
       v64i1          =  21,   //   64 x i1
enum SimpleValueType : uint8_t {
       v128i64        =  65,   // 128 x i64
       v256i64        =  66,   // 256 x i64
 
       v1i128         =  67,   //  1 x i128
 
       FIRST_INTEGER_FIXEDLEN_VECTOR_VALUETYPE = v1i1,
       LAST_INTEGER_FIXEDLEN_VECTOR_VALUETYPE = v1i128,
 
       v2f16          =  68,   //    2 x f16
       v3f16          =  69,   //    3 x f16
       v4f16          =  70,   //    4 x f16
       v8f16          =  71,   //    8 x f16
       v16f16         =  72,   //   16 x f16
       v32f16         =  73,   //   32 x f16
       v64f16         =  74,   //   64 x f16
       v128f16        =  75,   //  128 x f16
       v2bf16         =  76,   //    2 x bf16
enum SimpleValueType : uint8_t {
       v256f64        = 106,   //  256 x f64
 
       FIRST_FP_FIXEDLEN_VECTOR_VALUETYPE = v2f16,
       LAST_FP_FIXEDLEN_VECTOR_VALUETYPE = v256f64,
 
       FIRST_FIXEDLEN_VECTOR_VALUETYPE = v1i1,
       LAST_FIXEDLEN_VECTOR_VALUETYPE = v256f64,
 
       nxv1i1         = 107,   // n x  1 x i1
       nxv2i1         = 108,   // n x  2 x i1
       nxv4i1         = 109,   // n x  4 x i1
       nxv8i1         = 110,   // n x  8 x i1
       nxv16i1        = 111,   // n x 16 x i1
       nxv32i1        = 112,   // n x 32 x i1
       nxv64i1        = 113,   // n x  64 x i1
 
       nxv1i8         = 114,   // n x  1 x i8
enum SimpleValueType : uint8_t {
       nxv4i64        = 135,  // n x  4 x i64
       nxv8i64        = 136,  // n x  8 x i64
       nxv16i64       = 137,  // n x 16 x i64
       nxv32i64       = 138,  // n x 32 x i64
 
       FIRST_INTEGER_SCALABLE_VECTOR_VALUETYPE = nxv1i1,
       LAST_INTEGER_SCALABLE_VECTOR_VALUETYPE = nxv32i64,
 
       nxv1f16        = 139,   // n x   1 x f16
       nxv2f16        = 140,  // n x  2 x f16
       nxv4f16        = 141,  // n x  4 x f16
       nxv8f16        = 142,  // n x  8 x f16
       nxv16f16       = 143,   // n x  16 x f16
       nxv32f16       = 144,   // n x  32 x f16
       nxv2bf16       = 145,  // n x  2 x bf16
       nxv4bf16       = 146,  // n x  4 x bf16
       nxv8bf16       = 147,  // n x  8 x bf16
enum SimpleValueType : uint8_t {
 
       FIRST_FP_SCALABLE_VECTOR_VALUETYPE = nxv1f16,
       LAST_FP_SCALABLE_VECTOR_VALUETYPE = nxv8f64,
 
       FIRST_SCALABLE_VECTOR_VALUETYPE = nxv1i1,
       LAST_SCALABLE_VECTOR_VALUETYPE = nxv8f64,
 
       FIRST_VECTOR_VALUETYPE = v1i1,
       LAST_VECTOR_VALUETYPE  = nxv8f64,
 
       x86mmx         = 157,   // This is an X86 MMX value
 
       Glue           = 158,   // This glues nodes together during pre-RA sched
 
       isVoid         = 159,   // This has no value
 
       Untyped        = 160,   // This value takes a register, but has
                               // unspecified type.  The register class
                               // will be determined by the opcode.
 
-      exnref         = 161,   // WebAssembly's exnref type
-      funcref        = 162,   // WebAssembly's funcref type
-      externref      = 163,   // WebAssembly's externref type
-      x86amx         = 164,   // This is an X86 AMX value
+      funcref        = 161,   // WebAssembly's funcref type
+      externref      = 162,   // WebAssembly's externref type
+      x86amx         = 163,   // This is an X86 AMX value
 
       FIRST_VALUETYPE =  1,   // This is always the beginning of the list.
-      LAST_VALUETYPE = 165,   // This always remains at the end of the list.
+      LAST_VALUETYPE = 164,   // This always remains at the end of the list.
 
       // This is the current maximum for LAST_VALUETYPE.
       // MVT::MAX_ALLOWED_VALUETYPE is used for asserts and to size bit vectors
       // This value must be a multiple of 32.
       MAX_ALLOWED_VALUETYPE = 192,
 
       // A value of type llvm::TokenTy
       token          = 248,
 
       // This is MDNode or MDString.
       Metadata       = 249,
 
       // An int value the size of the pointer of the current
       // target to any address space. This must only be used internal to
       // tblgen. Other than for overloading, we treat iPTRAny the same as iPTR.
       iPTRAny        = 250,
 
       // A vector with any length and element size. This is used
       // for intrinsics that have overloadings based on vector types.
       // This is only for tblgen's consumption!
       vAny           = 251,
 
       // Any floating-point or vector floating-point value. This is used
       // for intrinsics that have overloadings based on floating-point types.
       // This is only for tblgen's consumption!
       fAny           = 252,
 
       // An integer or vector integer value of any bit width. This is
       // used for intrinsics that have overloadings based on integer bit widths.
       // This is only for tblgen's consumption!
       iAny           = 253,
 
       // An int value the size of the pointer of the current
       // target.  This should only be used internal to tblgen!
       iPTR           = 254,
 
       // Any type. This is used for intrinsics that have overloadings.
       // This is only for tblgen's consumption!
       Any            = 255
     };
 
     SimpleValueType SimpleTy = INVALID_SIMPLE_VALUE_TYPE;
 
     constexpr MVT() = default;
     constexpr MVT(SimpleValueType SVT) : SimpleTy(SVT) {}
 
     bool operator>(const MVT& S)  const { return SimpleTy >  S.SimpleTy; }
TypeSize getSizeInBits() const {
       case v512i32:
       case v256i64:
       case v512f32:
       case v256f64:  return TypeSize::Fixed(16384);
       case v1024i32:
       case v1024f32:  return TypeSize::Fixed(32768);
       case v2048i32:
       case v2048f32:  return TypeSize::Fixed(65536);
-      case exnref:
       case funcref:
       case externref: return TypeSize::Fixed(0); // opaque type
       }
     }
 
     /// Return the size of the specified fixed width value type in bits. The
     /// function will assert if the type is scalable.
     uint64_t getFixedSizeInBits() const {

llvm/lib/CodeGen/AsmPrinter/WasmException.cpp

 
 #include "WasmException.h"
 #include "llvm/IR/Mangler.h"
 #include "llvm/MC/MCContext.h"
 #include "llvm/MC/MCStreamer.h"
 using namespace llvm;
 
 void WasmException::endModule() {
-  // This is the symbol used in 'throw' and 'br_on_exn' instruction to denote
-  // this is a C++ exception. This symbol has to be emitted somewhere once in
-  // the module.  Check if the symbol has already been created, i.e., we have at
-  // least one 'throw' or 'br_on_exn' instruction in the module, and emit the
-  // symbol only if so.
+  // This is the symbol used in 'throw' and 'catch' instruction to denote this
+  // is a C++ exception. This symbol has to be emitted somewhere once in the
+  // module.  Check if the symbol has already been created, i.e., we have at
+  // least one 'throw' or 'catch' instruction in the module, and emit the symbol
+  // only if so.
   SmallString<60> NameStr;
   Mangler::getNameWithPrefix(NameStr, "__cpp_exception", Asm->getDataLayout());
   if (Asm->OutContext.lookupSymbol(NameStr)) {
     MCSymbol *ExceptionSym = Asm->GetExternalSymbolSymbol("__cpp_exception");
     Asm->OutStreamer->emitLabel(ExceptionSym);
   }
 }
 

llvm/lib/CodeGen/ValueTypes.cpp

std::string EVT::getEVTString() const {
   case MVT::ppcf128:   return "ppcf128";
   case MVT::isVoid:    return "isVoid";
   case MVT::Other:     return "ch";
   case MVT::Glue:      return "glue";
   case MVT::x86mmx:    return "x86mmx";
   case MVT::x86amx:    return "x86amx";
   case MVT::Metadata:  return "Metadata";
   case MVT::Untyped:   return "Untyped";
-  case MVT::exnref:    return "exnref";
   case MVT::funcref:   return "funcref";
   case MVT::externref: return "externref";
   }
 }
 
 /// getTypeForEVT - This method returns an LLVM type corresponding to the
 /// specified EVT.  For integer types, this returns an unsigned type.  Note
 /// that this will abort for types that cannot be represented.

llvm/lib/ObjectYAML/WasmYAML.cpp

void ScalarEnumerationTraits<WasmYAML::ValueType>::enumeration(
     IO &IO, WasmYAML::ValueType &Type) {
 #define ECase(X) IO.enumCase(Type, #X, wasm::WASM_TYPE_##X);
   ECase(I32);
   ECase(I64);
   ECase(F32);
   ECase(F64);
   ECase(V128);
   ECase(FUNCREF);
-  ECase(EXNREF);
   ECase(EXTERNREF);
   ECase(FUNC);
 #undef ECase
 }
 
 void ScalarEnumerationTraits<WasmYAML::ExportKind>::enumeration(
     IO &IO, WasmYAML::ExportKind &Kind) {
 #define ECase(X) IO.enumCase(Kind, #X, wasm::WASM_EXTERNAL_##X);

llvm/lib/Target/WebAssembly/AsmParser/WebAssemblyAsmParser.cpp

Optional<wasm::ValType> parseType(const StringRef &Type) {
     if (Type == "f32")
       return wasm::ValType::F32;
     if (Type == "f64")
       return wasm::ValType::F64;
     if (Type == "v128" || Type == "i8x16" || Type == "i16x8" ||
         Type == "i32x4" || Type == "i64x2" || Type == "f32x4" ||
         Type == "f64x2")
       return wasm::ValType::V128;
-    if (Type == "exnref")
-      return wasm::ValType::EXNREF;
     if (Type == "funcref")
       return wasm::ValType::FUNCREF;
     if (Type == "externref")
       return wasm::ValType::EXTERNREF;
     return Optional<wasm::ValType>();
   }
 
   WebAssembly::BlockType parseBlockType(StringRef ID) {
     // Multivalue block types are handled separately in parseSignature
     return StringSwitch<WebAssembly::BlockType>(ID)
         .Case("i32", WebAssembly::BlockType::I32)
         .Case("i64", WebAssembly::BlockType::I64)
         .Case("f32", WebAssembly::BlockType::F32)
         .Case("f64", WebAssembly::BlockType::F64)
         .Case("v128", WebAssembly::BlockType::V128)
         .Case("funcref", WebAssembly::BlockType::Funcref)
         .Case("externref", WebAssembly::BlockType::Externref)
-        .Case("exnref", WebAssembly::BlockType::Exnref)
         .Case("void", WebAssembly::BlockType::Void)
         .Default(WebAssembly::BlockType::Invalid);
   }
 
   bool parseRegTypeList(SmallVectorImpl<wasm::ValType> &Types) {
     while (Lexer.is(AsmToken::Identifier)) {
       auto Type = parseType(Lexer.getTok().getString());
       if (!Type)

llvm/lib/Target/WebAssembly/MCTargetDesc/WebAssemblyInstPrinter.cpp

const char *WebAssembly::anyTypeToString(unsigned Ty) {
   case wasm::WASM_TYPE_V128:
     return "v128";
   case wasm::WASM_TYPE_FUNCREF:
     return "funcref";
   case wasm::WASM_TYPE_EXTERNREF:
     return "externref";
   case wasm::WASM_TYPE_FUNC:
     return "func";
-  case wasm::WASM_TYPE_EXNREF:
-    return "exnref";
   case wasm::WASM_TYPE_NORESULT:
     return "void";
   default:
     return "invalid_type";
   }
 }
 
 const char *WebAssembly::typeToString(wasm::ValType Ty) {

llvm/lib/Target/WebAssembly/MCTargetDesc/WebAssemblyMCTargetDesc.h

enum class BlockType : unsigned {
   Void = 0x40,
   I32 = unsigned(wasm::ValType::I32),
   I64 = unsigned(wasm::ValType::I64),
   F32 = unsigned(wasm::ValType::F32),
   F64 = unsigned(wasm::ValType::F64),
   V128 = unsigned(wasm::ValType::V128),
   Externref = unsigned(wasm::ValType::EXTERNREF),
   Funcref = unsigned(wasm::ValType::FUNCREF),
-  Exnref = unsigned(wasm::ValType::EXNREF),
   // Multivalue blocks (and other non-void blocks) are only emitted when the
   // blocks will never be exited and are at the ends of functions (see
   // WebAssemblyCFGStackify::fixEndsAtEndOfFunction). They also are never made
   // to pop values off the stack, so the exact multivalue signature can always
   // be inferred from the return type of the parent function in MCInstLower.
   Multivalue = 0xffff,
 };
 
inline bool isArgument(unsigned Opc) {
   case WebAssembly::ARGUMENT_v4f32:
   case WebAssembly::ARGUMENT_v4f32_S:
   case WebAssembly::ARGUMENT_v2f64:
   case WebAssembly::ARGUMENT_v2f64_S:
   case WebAssembly::ARGUMENT_funcref:
   case WebAssembly::ARGUMENT_funcref_S:
   case WebAssembly::ARGUMENT_externref:
   case WebAssembly::ARGUMENT_externref_S:
-  case WebAssembly::ARGUMENT_exnref:
-  case WebAssembly::ARGUMENT_exnref_S:
     return true;
   default:
     return false;
   }
 }
 
 inline bool isCopy(unsigned Opc) {
   switch (Opc) {
   case WebAssembly::COPY_I32:
   case WebAssembly::COPY_I32_S:
   case WebAssembly::COPY_I64:
   case WebAssembly::COPY_I64_S:
   case WebAssembly::COPY_F32:
   case WebAssembly::COPY_F32_S:
   case WebAssembly::COPY_F64:
   case WebAssembly::COPY_F64_S:
   case WebAssembly::COPY_V128:
   case WebAssembly::COPY_V128_S:
   case WebAssembly::COPY_FUNCREF:
   case WebAssembly::COPY_FUNCREF_S:
   case WebAssembly::COPY_EXTERNREF:
   case WebAssembly::COPY_EXTERNREF_S:
-  case WebAssembly::COPY_EXNREF:
-  case WebAssembly::COPY_EXNREF_S:
     return true;
   default:
     return false;
   }
 }
 
 inline bool isTee(unsigned Opc) {
   switch (Opc) {
   case WebAssembly::TEE_I32:
   case WebAssembly::TEE_I32_S:
   case WebAssembly::TEE_I64:
   case WebAssembly::TEE_I64_S:
   case WebAssembly::TEE_F32:
   case WebAssembly::TEE_F32_S:
   case WebAssembly::TEE_F64:
   case WebAssembly::TEE_F64_S:
   case WebAssembly::TEE_V128:
   case WebAssembly::TEE_V128_S:
   case WebAssembly::TEE_FUNCREF:
   case WebAssembly::TEE_FUNCREF_S:
   case WebAssembly::TEE_EXTERNREF:
   case WebAssembly::TEE_EXTERNREF_S:
-  case WebAssembly::TEE_EXNREF:
-  case WebAssembly::TEE_EXNREF_S:
     return true;
   default:
     return false;
   }
 }
 
 inline bool isCallDirect(unsigned Opc) {
   switch (Opc) {

llvm/lib/Target/WebAssembly/MCTargetDesc/WebAssemblyMCTargetDesc.cpp

wasm::ValType WebAssembly::toValType(const MVT &Ty) {
   case MVT::v2i64:
   case MVT::v4f32:
   case MVT::v2f64:
     return wasm::ValType::V128;
   case MVT::funcref:
     return wasm::ValType::FUNCREF;
   case MVT::externref:
     return wasm::ValType::EXTERNREF;
-  case MVT::exnref:
-    return wasm::ValType::EXNREF;
   default:
     llvm_unreachable("unexpected type");
   }
 }

llvm/lib/Target/WebAssembly/WebAssemblyAsmPrinter.cpp

static char getInvokeSig(wasm::ValType VT) {
   case wasm::ValType::I64:
     return 'j';
   case wasm::ValType::F32:
     return 'f';
   case wasm::ValType::F64:
     return 'd';
   case wasm::ValType::V128:
     return 'V';
-  case wasm::ValType::EXNREF:
-    return 'E';
   case wasm::ValType::FUNCREF:
     return 'F';
   case wasm::ValType::EXTERNREF:
     return 'X';
   }
   llvm_unreachable("Unhandled wasm::ValType enum");
 }
 
if (isVerbose()) {
       OutStreamer->AddBlankLine();
     }
     break;
   }
   case WebAssembly::COMPILER_FENCE:
     // This is a compiler barrier that prevents instruction reordering during
     // backend compilation, and should not be emitted.
     break;
-  case WebAssembly::EXTRACT_EXCEPTION_I32:
-  case WebAssembly::EXTRACT_EXCEPTION_I32_S:
-    // These are pseudo instructions that simulates popping values from stack.
-    // We print these only when we have -wasm-keep-registers on for assembly
-    // readability.
-    if (!WasmKeepRegisters)
-      break;
-    LLVM_FALLTHROUGH;
   default: {
     WebAssemblyMCInstLower MCInstLowering(OutContext, *this);
     MCInst TmpInst;
     MCInstLowering.lower(MI, TmpInst);
     EmitToStreamer(*OutStreamer, TmpInst);
     break;
   }
   }

llvm/lib/Target/WebAssembly/WebAssemblyCFGStackify.cpp

void WebAssemblyCFGStackify::placeBlockMarker(MachineBasicBlock &MBB) {
   const auto &TII = *MF.getSubtarget<WebAssemblySubtarget>().getInstrInfo();
   const auto &MFI = *MF.getInfo<WebAssemblyFunctionInfo>();
 
   // First compute the nearest common dominator of all forward non-fallthrough
   // predecessors so that we minimize the time that the BLOCK is on the stack,
   // which reduces overall stack height.
   MachineBasicBlock *Header = nullptr;
   bool IsBranchedTo = false;
-  bool IsBrOnExn = false;
-  MachineInstr *BrOnExn = nullptr;
   int MBBNumber = MBB.getNumber();
   for (MachineBasicBlock *Pred : MBB.predecessors()) {
     if (Pred->getNumber() < MBBNumber) {
       Header = Header ? MDT.findNearestCommonDominator(Header, Pred) : Pred;
-      if (explicitlyBranchesTo(Pred, &MBB)) {
+      if (explicitlyBranchesTo(Pred, &MBB))
         IsBranchedTo = true;
-        if (Pred->getFirstTerminator()->getOpcode() == WebAssembly::BR_ON_EXN) {
-          IsBrOnExn = true;
-          assert(!BrOnExn && "There should be only one br_on_exn per block");
-          BrOnExn = &*Pred->getFirstTerminator();
-        }
-      }
     }
   }
   if (!Header)
     return;
   if (!IsBranchedTo)
     return;
 
   assert(&MBB != &MF.front() && "Header blocks shouldn't have predecessors");
if (std::prev(I)->isDebugInstr() || std::prev(I)->isPosition())
       continue;
     if (WebAssembly::isChild(*std::prev(I), MFI))
       AfterSet.insert(&*std::prev(I));
     else
       break;
   }
 
   // Add the BLOCK.
-
-  // 'br_on_exn' extracts exnref object and pushes variable number of values
-  // depending on its tag. For C++ exception, its a single i32 value, and the
-  // generated code will be in the form of:
-  // block i32
-  //   br_on_exn 0, $__cpp_exception
-  //   rethrow
-  // end_block
   WebAssembly::BlockType ReturnType = WebAssembly::BlockType::Void;
-  if (IsBrOnExn) {
-    const char *TagName = BrOnExn->getOperand(1).getSymbolName();
-    if (std::strcmp(TagName, "__cpp_exception") != 0)
-      llvm_unreachable("Only C++ exception is supported");
-    ReturnType = WebAssembly::BlockType::I32;
-  }
-
   auto InsertPos = getLatestInsertPos(Header, BeforeSet, AfterSet);
   MachineInstr *Begin =
       BuildMI(*Header, InsertPos, Header->findDebugLoc(InsertPos),
               TII.get(WebAssembly::BLOCK))
           .addImm(int64_t(ReturnType));
 
   // Decide where in Header to put the END_BLOCK.
   BeforeSet.clear();
static unsigned getCopyOpcode(const TargetRegisterClass *RC) {
   if (RC == &WebAssembly::F64RegClass)
     return WebAssembly::COPY_F64;
   if (RC == &WebAssembly::V128RegClass)
     return WebAssembly::COPY_V128;
   if (RC == &WebAssembly::FUNCREFRegClass)
     return WebAssembly::COPY_FUNCREF;
   if (RC == &WebAssembly::EXTERNREFRegClass)
     return WebAssembly::COPY_EXTERNREF;
-  if (RC == &WebAssembly::EXNREFRegClass)
-    return WebAssembly::COPY_EXNREF;
   llvm_unreachable("Unexpected register class");
 }
 
 // When MBB is split into MBB and Split, we should unstackify defs in MBB that
 // have their uses in Split.
 // FIXME This function will be used when fixing unwind mismatches, but the old
 // version of that function was removed for the moment and the new version has
 // not yet been added. So 'LLVM_ATTRIBUTE_UNUSED' is added to suppress the

llvm/lib/Target/WebAssembly/WebAssemblyExplicitLocals.cpp

static unsigned getDropOpcode(const TargetRegisterClass *RC) {
   if (RC == &WebAssembly::F64RegClass)
     return WebAssembly::DROP_F64;
   if (RC == &WebAssembly::V128RegClass)
     return WebAssembly::DROP_V128;
   if (RC == &WebAssembly::FUNCREFRegClass)
     return WebAssembly::DROP_FUNCREF;
   if (RC == &WebAssembly::EXTERNREFRegClass)
     return WebAssembly::DROP_EXTERNREF;
-  if (RC == &WebAssembly::EXNREFRegClass)
-    return WebAssembly::DROP_EXNREF;
   llvm_unreachable("Unexpected register class");
 }
 
 /// Get the appropriate local.get opcode for the given register class.
 static unsigned getLocalGetOpcode(const TargetRegisterClass *RC) {
   if (RC == &WebAssembly::I32RegClass)
     return WebAssembly::LOCAL_GET_I32;
   if (RC == &WebAssembly::I64RegClass)
     return WebAssembly::LOCAL_GET_I64;
   if (RC == &WebAssembly::F32RegClass)
     return WebAssembly::LOCAL_GET_F32;
   if (RC == &WebAssembly::F64RegClass)
     return WebAssembly::LOCAL_GET_F64;
   if (RC == &WebAssembly::V128RegClass)
     return WebAssembly::LOCAL_GET_V128;
-  if (RC == &WebAssembly::EXNREFRegClass)
-    return WebAssembly::LOCAL_GET_EXNREF;
   if (RC == &WebAssembly::FUNCREFRegClass)
     return WebAssembly::LOCAL_GET_FUNCREF;
   if (RC == &WebAssembly::EXTERNREFRegClass)
     return WebAssembly::LOCAL_GET_EXTERNREF;
   llvm_unreachable("Unexpected register class");
 }
 
 /// Get the appropriate local.set opcode for the given register class.
 static unsigned getLocalSetOpcode(const TargetRegisterClass *RC) {
   if (RC == &WebAssembly::I32RegClass)
     return WebAssembly::LOCAL_SET_I32;
   if (RC == &WebAssembly::I64RegClass)
     return WebAssembly::LOCAL_SET_I64;
   if (RC == &WebAssembly::F32RegClass)
     return WebAssembly::LOCAL_SET_F32;
   if (RC == &WebAssembly::F64RegClass)
     return WebAssembly::LOCAL_SET_F64;
   if (RC == &WebAssembly::V128RegClass)
     return WebAssembly::LOCAL_SET_V128;
-  if (RC == &WebAssembly::EXNREFRegClass)
-    return WebAssembly::LOCAL_SET_EXNREF;
   if (RC == &WebAssembly::FUNCREFRegClass)
     return WebAssembly::LOCAL_SET_FUNCREF;
   if (RC == &WebAssembly::EXTERNREFRegClass)
     return WebAssembly::LOCAL_SET_EXTERNREF;
   llvm_unreachable("Unexpected register class");
 }
 
 /// Get the appropriate local.tee opcode for the given register class.
 static unsigned getLocalTeeOpcode(const TargetRegisterClass *RC) {
   if (RC == &WebAssembly::I32RegClass)
     return WebAssembly::LOCAL_TEE_I32;
   if (RC == &WebAssembly::I64RegClass)
     return WebAssembly::LOCAL_TEE_I64;
   if (RC == &WebAssembly::F32RegClass)
     return WebAssembly::LOCAL_TEE_F32;
   if (RC == &WebAssembly::F64RegClass)
     return WebAssembly::LOCAL_TEE_F64;
   if (RC == &WebAssembly::V128RegClass)
     return WebAssembly::LOCAL_TEE_V128;
-  if (RC == &WebAssembly::EXNREFRegClass)
-    return WebAssembly::LOCAL_TEE_EXNREF;
   if (RC == &WebAssembly::FUNCREFRegClass)
     return WebAssembly::LOCAL_TEE_FUNCREF;
   if (RC == &WebAssembly::EXTERNREFRegClass)
     return WebAssembly::LOCAL_TEE_EXTERNREF;
   llvm_unreachable("Unexpected register class");
 }
 
 /// Get the type associated with the given register class.
 static MVT typeForRegClass(const TargetRegisterClass *RC) {
   if (RC == &WebAssembly::I32RegClass)
     return MVT::i32;
   if (RC == &WebAssembly::I64RegClass)
     return MVT::i64;
   if (RC == &WebAssembly::F32RegClass)
     return MVT::f32;
   if (RC == &WebAssembly::F64RegClass)
     return MVT::f64;
   if (RC == &WebAssembly::V128RegClass)
     return MVT::v16i8;
-  if (RC == &WebAssembly::EXNREFRegClass)
-    return MVT::exnref;
   if (RC == &WebAssembly::FUNCREFRegClass)
     return MVT::funcref;
   if (RC == &WebAssembly::EXTERNREFRegClass)
     return MVT::externref;
   llvm_unreachable("unrecognized register class");
 }
 
 /// Given a MachineOperand of a stackified vreg, return the instruction at the

llvm/lib/Target/WebAssembly/WebAssemblyFastISel.cpp

MVT::SimpleValueType getLegalType(MVT::SimpleValueType VT) {
     case MVT::i1:
     case MVT::i8:
     case MVT::i16:
       return MVT::i32;
     case MVT::i32:
     case MVT::i64:
     case MVT::f32:
     case MVT::f64:
-    case MVT::exnref:
     case MVT::funcref:
     case MVT::externref:
       return VT;
     case MVT::f16:
       return MVT::f32;
     case MVT::v16i8:
     case MVT::v8i16:
     case MVT::v4i32:
for (auto const &Arg : F->args()) {
     case MVT::funcref:
       Opc = WebAssembly::ARGUMENT_funcref;
       RC = &WebAssembly::FUNCREFRegClass;
       break;
     case MVT::externref:
       Opc = WebAssembly::ARGUMENT_externref;
       RC = &WebAssembly::EXTERNREFRegClass;
       break;
-    case MVT::exnref:
-      Opc = WebAssembly::ARGUMENT_exnref;
-      RC = &WebAssembly::EXNREFRegClass;
-      break;
     default:
       return false;
     }
     unsigned ResultReg = createResultReg(RC);
     BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(Opc), ResultReg)
         .addImm(I);
     updateValueMap(&Arg, ResultReg);
 
case MVT::v2i64:
       ResultReg = createResultReg(&WebAssembly::V128RegClass);
       break;
     case MVT::v4f32:
       ResultReg = createResultReg(&WebAssembly::V128RegClass);
       break;
     case MVT::v2f64:
       ResultReg = createResultReg(&WebAssembly::V128RegClass);
       break;
-    case MVT::exnref:
-      ResultReg = createResultReg(&WebAssembly::EXNREFRegClass);
-      break;
     case MVT::funcref:
       ResultReg = createResultReg(&WebAssembly::FUNCREFRegClass);
       break;
     case MVT::externref:
       ResultReg = createResultReg(&WebAssembly::EXTERNREFRegClass);
       break;
     default:
       return false;
bool WebAssemblyFastISel::selectSelect(const Instruction *I) {
   case MVT::f32:
     Opc = WebAssembly::SELECT_F32;
     RC = &WebAssembly::F32RegClass;
     break;
   case MVT::f64:
     Opc = WebAssembly::SELECT_F64;
     RC = &WebAssembly::F64RegClass;
     break;
-  case MVT::exnref:
-    Opc = WebAssembly::SELECT_EXNREF;
-    RC = &WebAssembly::EXNREFRegClass;
-    break;
   case MVT::funcref:
     Opc = WebAssembly::SELECT_FUNCREF;
     RC = &WebAssembly::FUNCREFRegClass;
     break;
   case MVT::externref:
     Opc = WebAssembly::SELECT_EXTERNREF;
     RC = &WebAssembly::EXTERNREFRegClass;
     break;
bool WebAssemblyFastISel::selectRet(const Instruction *I) {
   case MVT::v16i8:
   case MVT::v8i16:
   case MVT::v4i32:
   case MVT::v2i64:
   case MVT::v4f32:
   case MVT::v2f64:
   case MVT::funcref:
   case MVT::externref:
-  case MVT::exnref:
     break;
   default:
     return false;
   }
 
   unsigned Reg;
   if (FuncInfo.Fn->getAttributes().hasAttribute(0, Attribute::SExt))
     Reg = getRegForSignedValue(RV);

llvm/lib/Target/WebAssembly/WebAssemblyInstrControl.td

 // Region within which an exception is caught: try / end_try
 let Uses = [VALUE_STACK], Defs = [VALUE_STACK] in {
 defm TRY     : NRI<(outs), (ins Signature:$sig), [], "try     \t$sig", 0x06>;
 defm END_TRY : NRI<(outs), (ins), [], "end_try", 0x0b>;
 } // Uses = [VALUE_STACK], Defs = [VALUE_STACK]
 
 // Catching an exception: catch / catch_all
 let hasCtrlDep = 1, hasSideEffects = 1 in {
-// TODO Currently 'catch' can only extract an i32, which is sufficient for C++
+// Currently 'catch' can only extract an i32, which is sufficient for C++
 // support, but according to the spec 'catch' can extract any number of values
 // based on the event type.
 defm CATCH : I<(outs I32:$dst), (ins event_op:$tag),
                (outs), (ins event_op:$tag),
                [(set I32:$dst,
                  (WebAssemblycatch (WebAssemblywrapper texternalsym:$tag)))],
                "catch   \t$dst, $tag", "catch   \t$tag", 0x07>;
 defm CATCH_ALL : NRI<(outs), (ins), [], "catch_all", 0x05>;
 }
 
-// Querying / extracing exception: br_on_exn
-// br_on_exn queries an exnref to see if it matches the corresponding exception
-// tag index. If true it branches to the given label and pushes the
-// corresponding argument values of the exception onto the stack.
-let isBranch = 1, isTerminator = 1, hasCtrlDep = 1 in
-defm BR_ON_EXN : I<(outs), (ins bb_op:$dst, event_op:$tag, EXNREF:$exn),
-                   (outs), (ins bb_op:$dst, event_op:$tag), [],
-                   "br_on_exn \t$dst, $tag, $exn", "br_on_exn \t$dst, $tag",
-                   0x0a>;
-// This is a pseudo instruction that simulates popping a value from stack, which
-// has been pushed by br_on_exn
-let isCodeGenOnly = 1, hasSideEffects = 1 in
-defm EXTRACT_EXCEPTION_I32 : NRI<(outs I32:$dst), (ins), [],
-                                 "extract_exception\t$dst">;
-
 // Pseudo instructions: cleanupret / catchret
 let isTerminator = 1, hasSideEffects = 1, isBarrier = 1, hasCtrlDep = 1,
     isPseudo = 1, isEHScopeReturn = 1 in {
   defm CLEANUPRET : NRI<(outs), (ins), [(cleanupret)], "cleanupret", 0>;
   defm CATCHRET : NRI<(outs), (ins bb_op:$dst, bb_op:$from),
                       [(catchret bb:$dst, bb:$from)], "catchret", 0>;
 } // isTerminator = 1, hasSideEffects = 1, isBarrier = 1, hasCtrlDep = 1,
   // isPseudo = 1, isEHScopeReturn = 1
 } // Predicates = [HasExceptionHandling]

llvm/lib/Target/WebAssembly/WebAssemblyInstrInfo.cpp

void WebAssemblyInstrInfo::copyPhysReg(MachineBasicBlock &MBB,
   else if (RC == &WebAssembly::F64RegClass)
     CopyOpcode = WebAssembly::COPY_F64;
   else if (RC == &WebAssembly::V128RegClass)
     CopyOpcode = WebAssembly::COPY_V128;
   else if (RC == &WebAssembly::FUNCREFRegClass)
     CopyOpcode = WebAssembly::COPY_FUNCREF;
   else if (RC == &WebAssembly::EXTERNREFRegClass)
     CopyOpcode = WebAssembly::COPY_EXTERNREF;
-  else if (RC == &WebAssembly::EXNREFRegClass)
-    CopyOpcode = WebAssembly::COPY_EXNREF;
   else
     llvm_unreachable("Unexpected register class");
 
   BuildMI(MBB, I, DL, get(CopyOpcode), DestReg)
       .addReg(SrcReg, KillSrc ? RegState::Kill : 0);
 }
 
 MachineInstr *WebAssemblyInstrInfo::commuteInstructionImpl(
case WebAssembly::BR_UNLESS:
       HaveCond = true;
       break;
     case WebAssembly::BR:
       if (!HaveCond)
         TBB = MI.getOperand(0).getMBB();
       else
         FBB = MI.getOperand(0).getMBB();
       break;
-    case WebAssembly::BR_ON_EXN:
-      if (HaveCond)
-        return true;
-      Cond.push_back(MachineOperand::CreateImm(true));
-      Cond.push_back(MI.getOperand(2));
-      TBB = MI.getOperand(0).getMBB();
-      HaveCond = true;
-      break;
     }
     if (MI.isBarrier())
       break;
   }
 
   return false;
 }
 
if (!TBB)
       return 0;
 
     BuildMI(&MBB, DL, get(WebAssembly::BR)).addMBB(TBB);
     return 1;
   }
 
   assert(Cond.size() == 2 && "Expected a flag and a successor block");
 
-  MachineFunction &MF = *MBB.getParent();
-  auto &MRI = MF.getRegInfo();
-  bool IsBrOnExn = Cond[1].isReg() && MRI.getRegClass(Cond[1].getReg()) ==
-                                          &WebAssembly::EXNREFRegClass;
-
-  if (Cond[0].getImm()) {
-    if (IsBrOnExn) {
-      const char *CPPExnSymbol = MF.createExternalSymbolName("__cpp_exception");
-      BuildMI(&MBB, DL, get(WebAssembly::BR_ON_EXN))
-          .addMBB(TBB)
-          .addExternalSymbol(CPPExnSymbol)
-          .add(Cond[1]);
-    } else
-      BuildMI(&MBB, DL, get(WebAssembly::BR_IF)).addMBB(TBB).add(Cond[1]);
-  } else {
-    assert(!IsBrOnExn && "br_on_exn does not have a reversed condition");
+  if (Cond[0].getImm())
+  else
     BuildMI(&MBB, DL, get(WebAssembly::BR_UNLESS)).addMBB(TBB).add(Cond[1]);
-  }
   if (!FBB)
     return 1;
 
   BuildMI(&MBB, DL, get(WebAssembly::BR)).addMBB(FBB);
   return 2;
 }
 
 bool WebAssemblyInstrInfo::reverseBranchCondition(
     SmallVectorImpl<MachineOperand> &Cond) const {
   assert(Cond.size() == 2 && "Expected a flag and a condition expression");
-
-  // br_on_exn's condition cannot be reversed
-  MachineFunction &MF = *Cond[1].getParent()->getParent()->getParent();
-  auto &MRI = MF.getRegInfo();
-  if (Cond[1].isReg() &&
-      MRI.getRegClass(Cond[1].getReg()) == &WebAssembly::EXNREFRegClass)
-    return true;
-
   Cond.front() = MachineOperand::CreateImm(!Cond.front().getImm());
   return false;
 }
 
 ArrayRef<std::pair<int, const char *>>
 WebAssemblyInstrInfo::getSerializableTargetIndices() const {
   static const std::pair<int, const char *> TargetIndices[] = {
       {WebAssembly::TI_LOCAL, "wasm-local"},
       {WebAssembly::TI_GLOBAL_FIXED, "wasm-global-fixed"},
       {WebAssembly::TI_OPERAND_STACK, "wasm-operand-stack"},
       {WebAssembly::TI_GLOBAL_RELOC, "wasm-global-reloc"}};
   return makeArrayRef(TargetIndices);
 }

llvm/lib/Target/WebAssembly/WebAssemblyInstrInfo.td

multiclass ARGUMENT<WebAssemblyRegClass reg, ValueType vt> {
   defm ARGUMENT_#vt :
     I<(outs reg:$res), (ins i32imm:$argno), (outs), (ins i32imm:$argno),
       [(set (vt reg:$res), (WebAssemblyargument timm:$argno))]>;
 }
 defm "": ARGUMENT<I32, i32>;
 defm "": ARGUMENT<I64, i64>;
 defm "": ARGUMENT<F32, f32>;
 defm "": ARGUMENT<F64, f64>;
-defm "": ARGUMENT<EXNREF, exnref>;
 defm "": ARGUMENT<FUNCREF, funcref>;
 defm "": ARGUMENT<EXTERNREF, externref>;
 
 // local.get and local.set are not generated by instruction selection; they
 // are implied by virtual register uses and defs.
 multiclass LOCAL<WebAssemblyRegClass vt> {
   let hasSideEffects = 0 in {
   // COPY is not an actual instruction in wasm, but since we allow local.get and

 
 } // hasSideEffects = 0
 }
 defm "" : LOCAL<I32>;
 defm "" : LOCAL<I64>;
 defm "" : LOCAL<F32>;
 defm "" : LOCAL<F64>;
 defm "" : LOCAL<V128>, Requires<[HasSIMD128]>;
-defm "" : LOCAL<EXNREF>, Requires<[HasExceptionHandling]>;
 defm "" : LOCAL<FUNCREF>, Requires<[HasReferenceTypes]>;
 defm "" : LOCAL<EXTERNREF>, Requires<[HasReferenceTypes]>;
 
 let isMoveImm = 1, isAsCheapAsAMove = 1, isReMaterializable = 1 in {
 defm CONST_I32 : I<(outs I32:$res), (ins i32imm_op:$imm),
                    (outs), (ins i32imm_op:$imm),
                    [(set I32:$res, imm:$imm)],
                    "i32.const\t$res, $imm", "i32.const\t$imm", 0x41>;

llvm/lib/Target/WebAssembly/WebAssemblyInstrRef.td

defm SELECT_#reg: I<(outs reg:$dst), (ins reg:$lhs, reg:$rhs, I32:$cond),
                         (select I32:$cond, reg:$lhs, reg:$rhs))],
                       vt#".select\t$dst, $lhs, $rhs, $cond",
                       vt#".select", 0x1b>,
                     Requires<[HasReferenceTypes]>;
 }
 
 defm "" : REF_I<FUNCREF, funcref>;
 defm "" : REF_I<EXTERNREF, externref>;
-defm "" : REF_I<EXNREF, exnref>;
 
-foreach reg = [FUNCREF, EXTERNREF, EXNREF] in {
+foreach reg = [FUNCREF, EXTERNREF] in {
 def : Pat<(select (i32 (setne I32:$cond, 0)), reg:$lhs, reg:$rhs),
           (!cast<Instruction>("SELECT_"#reg) reg:$lhs, reg:$rhs, I32:$cond)>;
 def : Pat<(select (i32 (seteq I32:$cond, 0)), reg:$lhs, reg:$rhs),
           (!cast<Instruction>("SELECT_"#reg) reg:$rhs, reg:$lhs, I32:$cond)>;
 }

llvm/lib/Target/WebAssembly/WebAssemblyPeephole.cpp

if (!MFI.isVRegStackified(Reg)) {
         CopyLocalOpc = WebAssembly::COPY_V128;
         break;
       case WebAssembly::FUNCREFRegClassID:
         CopyLocalOpc = WebAssembly::COPY_FUNCREF;
         break;
       case WebAssembly::EXTERNREFRegClassID:
         CopyLocalOpc = WebAssembly::COPY_EXTERNREF;
         break;
-      case WebAssembly::EXNREFRegClassID:
-        CopyLocalOpc = WebAssembly::COPY_EXNREF;
-        break;
       default:
         llvm_unreachable("Unexpected register class for return operand");
       }
       Register NewReg = MRI.createVirtualRegister(RegClass);
       BuildMI(MBB, MI, MI.getDebugLoc(), TII.get(CopyLocalOpc), NewReg)
           .addReg(Reg);
       MO.setReg(NewReg);
       MFI.stackifyVReg(MRI, NewReg);

llvm/lib/Target/WebAssembly/WebAssemblyRegStackify.cpp

for (auto MII = MBB.rbegin(); MII != MBB.rend(); ++MII) {
         if (DefI->isInlineAsm())
           continue;
 
         // Argument instructions represent live-in registers and not real
         // instructions.
         if (WebAssembly::isArgument(DefI->getOpcode()))
           continue;
 
-        // Currently catch's return value register cannot be stackified, because
-        // the wasm LLVM backend currently does not support live-in values
-        // entering blocks, which is a part of multi-value proposal.
-        //
-        // Once we support live-in values of wasm blocks, this can be:
-        // catch                           ; push exnref value onto stack
-        // block exnref -> i32
-        // br_on_exn $__cpp_exception      ; pop the exnref value
-        // end_block
-        //
-        // But because we don't support it yet, the catch instruction's dst
-        // register should be assigned to a local to be propagated across
-        // 'block' boundary now.
-        //
-        // TODO: Fix this once we support the multivalue blocks
-        if (DefI->getOpcode() == WebAssembly::CATCH)
-          continue;
-
         MachineOperand *Def = DefI->findRegisterDefOperand(Reg);
         assert(Def != nullptr);
 
         // Decide which strategy to take. Prefer to move a single-use value
         // over cloning it, and prefer cloning over introducing a tee.
         // For moving, we require the def to be in the same block as the use;
         // this makes things simpler (LiveIntervals' handleMove function only
         // supports intra-block moves) and it's MachineSink's job to catch all

llvm/lib/Target/WebAssembly/WebAssemblyRegisterInfo.td

 // These are also used a "types" in the generated assembly matcher.
 def I32_0 : WebAssemblyReg<"%i32.0">;
 def I64_0 : WebAssemblyReg<"%i64.0">;
 def F32_0 : WebAssemblyReg<"%f32.0">;
 def F64_0 : WebAssemblyReg<"%f64.0">;
 
 def V128_0: WebAssemblyReg<"%v128">;
 
-def EXNREF_0 : WebAssemblyReg<"%exnref.0">;
 def FUNCREF_0 : WebAssemblyReg<"%funcref.0">;
 def EXTERNREF_0 : WebAssemblyReg<"%externref.0">;
 
 // The value stack "register". This is an opaque entity which serves to order
 // uses and defs that must remain in LIFO order.
 def VALUE_STACK : WebAssemblyReg<"STACK">;
 
 // The incoming arguments "register". This is an opaque entity which serves to
 // order the ARGUMENT instructions that are emulating live-in registers and
 // must not be scheduled below other instructions.
 def ARGUMENTS : WebAssemblyReg<"ARGUMENTS">;
 
 //===----------------------------------------------------------------------===//
 //  Register classes
 //===----------------------------------------------------------------------===//
 
 def I32 : WebAssemblyRegClass<[i32], 32, (add FP32, SP32, I32_0)>;
 def I64 : WebAssemblyRegClass<[i64], 64, (add FP64, SP64, I64_0)>;
 def F32 : WebAssemblyRegClass<[f32], 32, (add F32_0)>;
 def F64 : WebAssemblyRegClass<[f64], 64, (add F64_0)>;
 def V128 : WebAssemblyRegClass<[v4f32, v2f64, v2i64, v4i32, v16i8, v8i16], 128,
                                (add V128_0)>;
-def EXNREF : WebAssemblyRegClass<[exnref], 0, (add EXNREF_0)>;
 def FUNCREF : WebAssemblyRegClass<[funcref], 0, (add FUNCREF_0)>;
 def EXTERNREF : WebAssemblyRegClass<[externref], 0, (add EXTERNREF_0)>;

llvm/test/CodeGen/WebAssembly/reg-argument.mir

body: |
   ; CHECK-LABEL: bb.0:
   ; CHECK-NEXT: %1:f64 = ARGUMENT_f64 0
   bb.0:
     %0:i32 = CONST_I32 0, implicit-def $arguments
     %1:f64 = ARGUMENT_f64 0, implicit $arguments
     RETURN implicit-def $arguments
 ...
 ---
-name: argument_exnref
-# CHECK-LABEL: argument_exnref
+name: argument_funcref
+# CHECK-LABEL: argument_funcref
 body: |
   ; CHECK-LABEL: bb.0:
-  ; CHECK-NEXT: %1:exnref = ARGUMENT_exnref 0
+  ; CHECK-NEXT: %1:funcref = ARGUMENT_funcref 0
   bb.0:
     %0:i32 = CONST_I32 0, implicit-def $arguments
-    %1:exnref = ARGUMENT_exnref 0, implicit $arguments
+    %1:funcref = ARGUMENT_funcref 0, implicit $arguments
+    RETURN implicit-def $arguments
+...
+---
+name: argument_externref
+# CHECK-LABEL: argument_externref
+body: |
+  ; CHECK-LABEL: bb.0:
+  ; CHECK-NEXT: %1:externref = ARGUMENT_externref 0
+  bb.0:
+    %0:i32 = CONST_I32 0, implicit-def $arguments
+    %1:externref = ARGUMENT_externref 0, implicit $arguments
     RETURN implicit-def $arguments
 ...

llvm/test/CodeGen/WebAssembly/reg-copy.mir

body: |
   ; CHECK-LABEL: bb.0:
   ; CHECK-NEXT: %0:v128 = COPY_V128 %1:v128
   ; CHECK-NEXT: RETURN
   bb.0:
     %0:v128 = COPY %1:v128
     RETURN implicit-def $arguments
 ...
 ---
-name: copy_exnref
-# CHECK-LABEL: copy_exnref
+name: copy_funcref
+# CHECK-LABEL: copy_funcref
 body: |
   ; CHECK-LABEL: bb.0:
-  ; CHECK-NEXT: %0:exnref = COPY_EXNREF %1:exnref
+  ; CHECK-NEXT: %0:funcref = COPY_FUNCREF %1:funcref
   ; CHECK-NEXT: RETURN
   bb.0:
-    %0:exnref = COPY %1:exnref
+    %0:funcref = COPY %1:funcref
+    RETURN implicit-def $arguments
+...
+---
+name: copy_externref
+# CHECK-LABEL: copy_externref
+body: |
+  ; CHECK-LABEL: bb.0:
+  ; CHECK-NEXT: %0:externref = COPY_EXTERNREF %1:externref
+  ; CHECK-NEXT: RETURN
+  bb.0:
+    %0:externref = COPY %1:externref
     RETURN implicit-def $arguments
 ...

llvm/test/MC/Disassembler/WebAssembly/wasm.txt

 0x02 0x7C
 
 # CHECK: call_indirect
 # $0=, 128, 0
 # FIXME: WebAssemblyInstPrinter does not print immediates.
 0x11 0x80 0x01 0x00
 
 # CHECK: call 0
-# CHECK-NOT: exnref.call 0
 0x10 0x00
 
 # CHECK: local.get 128
 0x20 0x80 0x01
 
 # Prefix byte example:
 # CHECK: i64.trunc_sat_f64_u
 0xFC 0x07

 
 # Check br_table, which has its own operand type.
 # CHECK: br_table {0, 1, 2}
 0x0E 0x02 0x00 0x01 0x02
 
 # This can mean end_block/end_loop/end_if/end_function/end_try..
 # CHECK: end
 0x0B
-
-# CHECK: br_on_exn 0, 0
-0x0A 0x00 0x00

llvm/test/MC/WebAssembly/objdump.s

 # RUN: llvm-mc -triple=wasm32-unknown-unknown -filetype=obj -o %t.o -mattr=+simd128,+nontrapping-fptoint,+exception-handling < %s
 # RUN: llvm-objdump --triple=wasm32-unknown-unknown -d %t.o | FileCheck %s
 
 test0:
     .functype   test0 (i32, i64) -> (i32)
     .local      f32, f64, v128, v128
     local.get   2
     end_function
 
 test1:
     .functype   test1 (i32, i64) -> (i32)
-    .local      i32, i64, exnref
+    .local      i32, i64, funcref
     local.get   3
     end_function
 
 
 # CHECK-LABEL: CODE:
 # CHECK:             # 2 functions in section.
 # CHECK-LABEL: <test0>:
 # CHECK-NEXT:        .local  f32, f64, v128, v128
 # CHECK-NEXT:       9:       20 02  local.get 2
 # CHECK-NEXT:       b:       0b     end
 # CHECK-LABEL: <test1>:
-# CHECK-NEXT:        .local  i32, i64, exnref
+# CHECK-NEXT:        .local  i32, i64, funcref
 # CHECK-NEXT:      14:       20 03  local.get 3
 # CHECK-NEXT:      16:       0b     end

llvm/utils/TableGen/CodeGenTarget.cpp

StringRef llvm::getEnumName(MVT::SimpleValueType T) {
   case MVT::nxv2f64:   return "MVT::nxv2f64";
   case MVT::nxv4f64:   return "MVT::nxv4f64";
   case MVT::nxv8f64:   return "MVT::nxv8f64";
   case MVT::token:     return "MVT::token";
   case MVT::Metadata:  return "MVT::Metadata";
   case MVT::iPTR:      return "MVT::iPTR";
   case MVT::iPTRAny:   return "MVT::iPTRAny";
   case MVT::Untyped:   return "MVT::Untyped";
-  case MVT::exnref:    return "MVT::exnref";
   case MVT::funcref:   return "MVT::funcref";
   case MVT::externref: return "MVT::externref";
   default: llvm_unreachable("ILLEGAL VALUE TYPE!");
   }
 }
 
 /// getQualifiedName - Return the name of the specified record, with a
 /// namespace qualifier if the record contains one.