IR: synchronize on SymbolTable operations

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/util/SymbolTable.kt

@@ -76,6 +76,7 @@ class SymbolTable(
         abstract fun get(sig: IdSignature): S?
 
         inline fun declare(d: D, createSymbol: () -> S, createOwner: (S) -> B): B {
+            synchronized(this) {
                 @Suppress("UNCHECKED_CAST")
                 val d0 = d.original as D
                 assert(d0 === d) {
@@ -92,9 +93,11 @@ class SymbolTable(
                 }
                 return createOwner(symbol)
             }
+        }
 
         @OptIn(ObsoleteDescriptorBasedAPI::class)
         inline fun declare(sig: IdSignature, createSymbol: () -> S, createOwner: (S) -> B): B {
+            synchronized(this) {
                 val existing = get(sig)
                 val symbol = if (existing == null) {
                     createSymbol()
@@ -107,8 +110,10 @@ class SymbolTable(
                 set(symbol)
                 return result
             }
+        }
 
         inline fun declareIfNotExists(d: D, createSymbol: () -> S, createOwner: (S) -> B): B {
+            synchronized(this) {
                 @Suppress("UNCHECKED_CAST")
                 val d0 = d.original as D
                 assert(d0 === d) {
@@ -125,8 +130,10 @@ class SymbolTable(
                 }
                 return if (symbol.isBound) symbol.owner else createOwner(symbol)
             }
+        }
 
         inline fun declare(sig: IdSignature, d: D?, createSymbol: () -> S, createOwner: (S) -> B): B {
+            synchronized(this) {
                 @Suppress("UNCHECKED_CAST")
                 val d0 = d?.original as D
                 assert(d0 === d) {
@@ -143,8 +150,10 @@ class SymbolTable(
                 }
                 return createOwner(symbol)
             }
+        }
 
         inline fun referenced(d: D, orElse: () -> S): S {
+            synchronized(this) {
                 @Suppress("UNCHECKED_CAST")
                 val d0 = d.original as D
                 assert(d0 === d) {
@@ -161,9 +170,11 @@ class SymbolTable(
                 }
                 return s
             }
+        }
 
         @OptIn(ObsoleteDescriptorBasedAPI::class)
         inline fun referenced(sig: IdSignature, orElse: () -> S): S {
+            synchronized(this) {
                 return get(sig) ?: run {
                     val new = orElse()
                     assert(unboundSymbols.add(new)) {
@@ -174,6 +185,7 @@ class SymbolTable(
                 }
             }
         }
+    }
 
     private open inner class FlatSymbolTable<D : DeclarationDescriptor, B : IrSymbolOwner, S : IrBindableSymbol<D, B>> :
         SymbolTableBase<D, B, S>() {