Remove unwind

`unwind` was removed. See WebAssembly/exception-handling#156.
aheejin · Jun 26, 2021 · 533607c · 533607c
1 parent 9500425
commit 533607c
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Showing 34 changed files with 11 additions and 339 deletions.
diff --git a/src/binary-reader-ir.cc b/src/binary-reader-ir.cc
@@ -199,7 +199,6 @@ class BinaryReaderIR : public BinaryReaderNop {
   Result OnUnaryExpr(Opcode opcode) override;
   Result OnTernaryExpr(Opcode opcode) override;
   Result OnUnreachableExpr() override;
-  Result OnUnwindExpr() override;
   Result EndFunctionBody(Index index) override;
   Result OnSimdLaneOpExpr(Opcode opcode, uint64_t value) override;
   Result OnSimdLoadLaneExpr(Opcode opcode,
@@ -813,7 +812,6 @@ Result BinaryReaderIR::OnEndExpr() {
 
     case LabelType::Func:
     case LabelType::Catch:
-    case LabelType::Unwind:
       break;
   }
 
@@ -1015,7 +1013,7 @@ Result BinaryReaderIR::AppendCatch(Catch&& catch_) {
   if (try_->kind == TryKind::Invalid) {
     try_->kind = TryKind::Catch;
   } else if (try_->kind != TryKind::Catch) {
-    PrintError("catch not allowed in try-unwind or try-delegate");
+    PrintError("catch not allowed in try-delegate");
     return Result::Error;
   }
 
@@ -1032,28 +1030,6 @@ Result BinaryReaderIR::OnCatchAllExpr() {
   return AppendCatch(Catch(GetLocation()));
 }
 
-Result BinaryReaderIR::OnUnwindExpr() {
-  LabelNode* label = nullptr;
-  CHECK_RESULT(TopLabel(&label));
-
-  if (label->label_type != LabelType::Try) {
-    PrintError("unwind not inside try block");
-    return Result::Error;
-  }
-
-  auto* try_ = cast<TryExpr>(label->context);
-
-  if (try_->kind == TryKind::Invalid) {
-    try_->kind = TryKind::Unwind;
-  } else if (try_->kind != TryKind::Unwind) {
-    PrintError("unwind not allowed in try-catch or try-delegate");
-    return Result::Error;
-  }
-
-  label->exprs = &try_->unwind;
-  return Result::Ok;
-}
-
 Result BinaryReaderIR::OnDelegateExpr(Index depth) {
   LabelNode* label = nullptr;
   CHECK_RESULT(TopLabel(&label));
@@ -1068,7 +1044,7 @@ Result BinaryReaderIR::OnDelegateExpr(Index depth) {
   if (try_->kind == TryKind::Invalid) {
     try_->kind = TryKind::Delegate;
   } else if (try_->kind != TryKind::Delegate) {
-    PrintError("delegate not allowed in try-catch or try-unwind");
+    PrintError("delegate not allowed in try-catch");
     return Result::Error;
   }
 

diff --git a/src/binary-reader-logging.cc b/src/binary-reader-logging.cc
@@ -844,7 +844,6 @@ DEFINE_LOAD_STORE_OPCODE(OnLoadZeroExpr);
 DEFINE_LOAD_STORE_OPCODE(OnStoreExpr);
 DEFINE_INDEX_DESC(OnThrowExpr, "tag_index")
 DEFINE0(OnUnreachableExpr)
-DEFINE0(OnUnwindExpr)
 DEFINE_OPCODE(OnUnaryExpr)
 DEFINE_OPCODE(OnTernaryExpr)
 DEFINE_SIMD_LOAD_STORE_LANE_OPCODE(OnSimdLoadLaneExpr);

diff --git a/src/binary-reader-logging.h b/src/binary-reader-logging.h
@@ -222,7 +222,6 @@ class BinaryReaderLogging : public BinaryReaderDelegate {
   Result OnUnaryExpr(Opcode opcode) override;
   Result OnTernaryExpr(Opcode opcode) override;
   Result OnUnreachableExpr() override;
-  Result OnUnwindExpr() override;
   Result OnAtomicWaitExpr(Opcode opcode,
                           Address alignment_log2,
                           Address offset) override;

diff --git a/src/binary-reader-nop.h b/src/binary-reader-nop.h
@@ -303,7 +303,6 @@ class BinaryReaderNop : public BinaryReaderDelegate {
   Result OnUnaryExpr(Opcode opcode) override { return Result::Ok; }
   Result OnTernaryExpr(Opcode opcode) override { return Result::Ok; }
   Result OnUnreachableExpr() override { return Result::Ok; }
-  Result OnUnwindExpr() override { return Result::Ok; }
   Result EndFunctionBody(Index index) override { return Result::Ok; }
   Result EndCodeSection() override { return Result::Ok; }
   Result OnSimdLaneOpExpr(Opcode opcode, uint64_t value) override {

diff --git a/src/binary-reader-objdump.cc b/src/binary-reader-objdump.cc
@@ -598,7 +598,6 @@ void BinaryReaderObjdumpDisassemble::LogOpcode(size_t data_size,
         case Opcode::Else:
         case Opcode::Catch:
         case Opcode::CatchAll:
-        case Opcode::Unwind:
           indent_level--;
         default:
           break;

diff --git a/src/binary-reader.cc b/src/binary-reader.cc
@@ -1435,12 +1435,6 @@ Result BinaryReader::ReadFunctionBody(Offset end_offset) {
         break;
       }
 
-      case Opcode::Unwind: {
-        CALLBACK0(OnUnwindExpr);
-        CALLBACK0(OnOpcodeBare);
-        break;
-      }
-
       case Opcode::Delegate: {
         Index index;
         CHECK_RESULT(ReadIndex(&index, "depth"));

diff --git a/src/binary-reader.h b/src/binary-reader.h
@@ -290,7 +290,6 @@ class BinaryReaderDelegate {
   virtual Result OnUnaryExpr(Opcode opcode) = 0;
   virtual Result OnTernaryExpr(Opcode opcode) = 0;
   virtual Result OnUnreachableExpr() = 0;
-  virtual Result OnUnwindExpr() = 0;
   virtual Result EndFunctionBody(Index index) = 0;
   virtual Result EndCodeSection() = 0;
 

diff --git a/src/binary-writer.cc b/src/binary-writer.cc
@@ -1006,11 +1006,6 @@ void BinaryWriter::WriteExpr(const Func* func, const Expr* expr) {
           }
           WriteOpcode(stream_, Opcode::End);
           break;
-        case TryKind::Unwind:
-          WriteOpcode(stream_, Opcode::Unwind);
-          WriteExprList(func, try_expr->unwind);
-          WriteOpcode(stream_, Opcode::End);
-          break;
         case TryKind::Delegate:
           WriteOpcode(stream_, Opcode::Delegate);
           WriteU32Leb128(stream_,

diff --git a/src/common.h b/src/common.h
@@ -230,10 +230,9 @@ enum class LabelType {
   Else,
   Try,
   Catch,
-  Unwind,
 
   First = Func,
-  Last = Unwind,
+  Last = Catch,
 };
 static const int kLabelTypeCount = WABT_ENUM_COUNT(LabelType);
 

diff --git a/src/expr-visitor.cc b/src/expr-visitor.cc
@@ -107,10 +107,6 @@ Result ExprVisitor::VisitExpr(Expr* root_expr) {
                 CHECK_RESULT(delegate_->EndTryExpr(try_expr));
               }
               break;
-            case TryKind::Unwind:
-              CHECK_RESULT(delegate_->OnUnwindExpr(try_expr));
-              PushExprlist(State::Unwind, expr, try_expr->unwind);
-              break;
             case TryKind::Delegate:
               CHECK_RESULT(delegate_->OnDelegateExpr(try_expr));
               break;
@@ -141,18 +137,6 @@ Result ExprVisitor::VisitExpr(Expr* root_expr) {
         }
         break;
       }
-
-      case State::Unwind: {
-        auto try_expr = cast<TryExpr>(expr);
-        auto& iter = expr_iter_stack_.back();
-        if (iter != try_expr->unwind.end()) {
-          PushDefault(&*iter++);
-        } else {
-          CHECK_RESULT(delegate_->EndTryExpr(try_expr));
-          PopExprlist();
-        }
-        break;
-      }
     }
   }
 

diff --git a/src/expr-visitor.h b/src/expr-visitor.h
@@ -42,7 +42,6 @@ class ExprVisitor {
     Loop,
     Try,
     Catch,
-    Unwind,
   };
 
   Result HandleDefaultState(Expr*);
@@ -118,7 +117,6 @@ class ExprVisitor::Delegate {
   virtual Result OnUnreachableExpr(UnreachableExpr*) = 0;
   virtual Result BeginTryExpr(TryExpr*) = 0;
   virtual Result OnCatchExpr(TryExpr*, Catch*) = 0;
-  virtual Result OnUnwindExpr(TryExpr*) = 0;
   virtual Result OnDelegateExpr(TryExpr*) = 0;
   virtual Result EndTryExpr(TryExpr*) = 0;
   virtual Result OnThrowExpr(ThrowExpr*) = 0;
@@ -193,7 +191,6 @@ class ExprVisitor::DelegateNop : public ExprVisitor::Delegate {
   Result OnUnreachableExpr(UnreachableExpr*) override { return Result::Ok; }
   Result BeginTryExpr(TryExpr*) override { return Result::Ok; }
   Result OnCatchExpr(TryExpr*, Catch*) override { return Result::Ok; }
-  Result OnUnwindExpr(TryExpr*) override { return Result::Ok; }
   Result OnDelegateExpr(TryExpr*) override { return Result::Ok; }
   Result EndTryExpr(TryExpr*) override { return Result::Ok; }
   Result OnThrowExpr(ThrowExpr*) override { return Result::Ok; }

diff --git a/src/interp/interp.cc b/src/interp/interp.cc
@@ -1794,7 +1794,6 @@ RunResult Thread::StepInternal(Trap::Ptr* out_trap) {
     case O::Try:
     case O::Catch:
     case O::CatchAll:
-    case O::Unwind:
     case O::Delegate:
     case O::Throw:
     case O::Rethrow:

diff --git a/src/interp/istream.cc b/src/interp/istream.cc
@@ -764,7 +764,6 @@ Instr Istream::Read(Offset* offset) const {
     case Opcode::Rethrow:
     case Opcode::Throw:
     case Opcode::Try:
-    case Opcode::Unwind:
     case Opcode::ReturnCall:
       // Not used.
       break;

diff --git a/src/ir.h b/src/ir.h
@@ -380,7 +380,6 @@ typedef std::vector<Catch> CatchVector;
 enum class TryKind {
   Invalid,
   Catch,
-  Unwind,
   Delegate
 };
 
@@ -609,7 +608,6 @@ class TryExpr : public ExprMixin<ExprType::Try> {
   TryKind kind;
   Block block;
   CatchVector catches;
-  ExprList unwind;
   Var delegate_target;
 };
 

diff --git a/src/lexer-keywords.txt b/src/lexer-keywords.txt
@@ -628,4 +628,3 @@ i64.trunc_u:sat/f64, TokenType::Convert, Opcode::I64TruncSatF64U
 set_global, TokenType::GlobalSet, Opcode::GlobalSet
 set_local, TokenType::LocalSet, Opcode::LocalSet
 tee_local, TokenType::LocalTee, Opcode::LocalTee
-unwind, TokenType::Unwind, Opcode::Unwind
diff --git a/src/opcode.cc b/src/opcode.cc
@@ -65,7 +65,6 @@ bool Opcode::IsEnabled(const Features& features) const {
   switch (enum_) {
     case Opcode::Try:
     case Opcode::Catch:
-    case Opcode::Unwind:
     case Opcode::Delegate:
     case Opcode::Throw:
     case Opcode::Rethrow:

diff --git a/src/opcode.def b/src/opcode.def
@@ -45,7 +45,6 @@ WABT_OPCODE(___,  ___,  ___,  ___,  0,  0,    0x06, Try, "try", "")
 WABT_OPCODE(___,  ___,  ___,  ___,  0,  0,    0x07, Catch, "catch", "")
 WABT_OPCODE(___,  ___,  ___,  ___,  0,  0,    0x08, Throw, "throw", "")
 WABT_OPCODE(___,  ___,  ___,  ___,  0,  0,    0x09, Rethrow, "rethrow", "")
-WABT_OPCODE(___,  ___,  ___,  ___,  0,  0,    0x0a, Unwind, "unwind", "")
 WABT_OPCODE(___,  ___,  ___,  ___,  0,  0,    0x0b, End, "end", "")
 WABT_OPCODE(___,  ___,  ___,  ___,  0,  0,    0x0c, Br, "br", "")
 WABT_OPCODE(___,  I32,  ___,  ___,  0,  0,    0x0d, BrIf, "br_if", "")

diff --git a/src/prebuilt/lexer-keywords.cc b/src/prebuilt/lexer-keywords.cc
@@ -158,7 +158,7 @@ Perfect_Hash::InWordSet (const char *str, size_t len)
 {
   enum
     {
-      TOTAL_KEYWORDS = 611,
+      TOTAL_KEYWORDS = 610,
       MIN_WORD_LENGTH = 2,
       MAX_WORD_LENGTH = 29,
       MIN_HASH_VALUE = 19,
@@ -457,8 +457,7 @@ Perfect_Hash::InWordSet (const char *str, size_t len)
       {"i64x2.bitmask", TokenType::Unary, Opcode::I64X2Bitmask},
 #line 383 "src/lexer-keywords.txt"
       {"i64.atomic.store32", TokenType::AtomicStore, Opcode::I64AtomicStore32},
-#line 631 "src/lexer-keywords.txt"
-      {"unwind", TokenType::Unwind, Opcode::Unwind},
+      {""},
 #line 407 "src/lexer-keywords.txt"
       {"i64.load32_u", TokenType::Load, Opcode::I64Load32U},
       {""},

diff --git a/src/shared-validator.cc b/src/shared-validator.cc
@@ -1241,11 +1241,4 @@ Result SharedValidator::OnUnreachable(const Location& loc) {
   return result;
 }
 
-Result SharedValidator::OnUnwind(const Location& loc) {
-  Result result = Result::Ok;
-  expr_loc_ = &loc;
-  result |= typechecker_.OnUnwind();
-  return result;
-}
-
 }  // namespace wabt
diff --git a/src/shared-validator.h b/src/shared-validator.h
@@ -175,7 +175,6 @@ class SharedValidator {
   Result OnTry(const Location&, Type sig_type);
   Result OnUnary(const Location&, Opcode);
   Result OnUnreachable(const Location&);
-  Result OnUnwind(const Location&);
 
  private:
   struct FuncType {

diff --git a/src/token.def b/src/token.def
@@ -145,9 +145,8 @@ WABT_TOKEN(Throw, "throw")
 WABT_TOKEN(Try, "try")
 WABT_TOKEN(Unary, "UNARY")
 WABT_TOKEN(Unreachable, "unreachable")
-WABT_TOKEN(Unwind, "unwind")
 WABT_TOKEN_FIRST(Opcode, AtomicFence)
-WABT_TOKEN_LAST(Opcode, Unwind)
+WABT_TOKEN_LAST(Opcode, Unreachable)
 
 /* Tokens with string data. */
 WABT_TOKEN(AlignEqNat, "align=")

diff --git a/src/type-checker.cc b/src/type-checker.cc
@@ -604,8 +604,7 @@ Result TypeChecker::OnEnd(Label* label,
 Result TypeChecker::OnEnd() {
   Result result = Result::Ok;
   static const char* s_label_type_name[] = {
-      "function", "block", "loop", "if", "if false branch", "try",
-      "try catch", "try unwind"};
+      "function", "block", "loop", "if", "if false branch", "try", "try catch"};
   WABT_STATIC_ASSERT(WABT_ARRAY_SIZE(s_label_type_name) == kLabelTypeCount);
   Label* label;
   CHECK_RESULT(TopLabel(&label));
@@ -618,15 +617,7 @@ Result TypeChecker::OnEnd() {
   }
 
   const char* desc = s_label_type_name[static_cast<int>(label->label_type)];
-  if (label->label_type == LabelType::Unwind) {
-    // Unwind is unusual in that it always unwinds the control stack at the end,
-    // and therefore the return type of the unwind expressions are not the same
-    // as the block return type.
-    TypeVector empty;
-    result |= OnEnd(label, empty, desc, desc);
-  } else {
-    result |= OnEnd(label, label->result_types, desc, desc);
-  }
+  result |= OnEnd(label, label->result_types, desc, desc);
   return result;
 }
 
@@ -914,19 +905,6 @@ Result TypeChecker::OnUnreachable() {
   return SetUnreachable();
 }
 
-Result TypeChecker::OnUnwind() {
-  Result result = Result::Ok;
-  Label* label;
-  CHECK_RESULT(TopLabel(&label));
-  result |= CheckLabelType(label, LabelType::Try);
-  result |= PopAndCheckSignature(label->result_types, "try block");
-  result |= CheckTypeStackEnd("try block");
-  ResetTypeStackToLabel(label);
-  label->label_type = LabelType::Unwind;
-  label->unreachable = false;
-  return result;
-}
-
 Result TypeChecker::EndFunction() {
   Result result = Result::Ok;
   Label* label;

diff --git a/src/type-checker.h b/src/type-checker.h
@@ -125,7 +125,6 @@ class TypeChecker {
   Result OnTry(const TypeVector& param_types, const TypeVector& result_types);
   Result OnUnary(Opcode);
   Result OnUnreachable();
-  Result OnUnwind();
   Result EndFunction();
 
   static Result CheckType(Type actual, Type expected);

diff --git a/src/validator.cc b/src/validator.cc
@@ -135,7 +135,6 @@ class Validator : public ExprVisitor::Delegate {
   Result OnUnreachableExpr(UnreachableExpr*) override;
   Result BeginTryExpr(TryExpr*) override;
   Result OnCatchExpr(TryExpr*, Catch*) override;
-  Result OnUnwindExpr(TryExpr*) override;
   Result OnDelegateExpr(TryExpr*) override;
   Result EndTryExpr(TryExpr*) override;
   Result OnThrowExpr(ThrowExpr*) override;
@@ -499,11 +498,6 @@ Result Validator::OnCatchExpr(TryExpr*, Catch* catch_) {
   return Result::Ok;
 }
 
-Result Validator::OnUnwindExpr(TryExpr* expr) {
-  result_ |= validator_.OnUnwind(expr->loc);
-  return Result::Ok;
-}
-
 Result Validator::OnDelegateExpr(TryExpr* expr) {
   result_ |= validator_.OnDelegate(expr->loc, expr->delegate_target);
   return Result::Ok;