Change synthetic accessor method names to "access$..."

As per discussion in https://youtrack.jetbrains.com/issue/KT-6870

compiler/testData/cli/jvm/signatureClash.kt

@@ -23,7 +23,7 @@ class SubTr : Tr {
 // Clashing synthetic accessors are only reported in compiler, IDE doesn't see them
 class C {
     private fun f() {}
-    fun `f$b$0`(c: C) {}
+    fun `access$f$0`(c: C) {}
 
     class Nested {
 
@@ -31,4 +31,4 @@ class C {
             C().f()
         }
     }
-}
+}

compiler/testData/cli/jvm/signatureClash.out

@@ -1,4 +1,4 @@
-WARNING: compiler/testData/cli/jvm/signatureClash.kt: (26, 17) Parameter 'c' is never used
+WARNING: compiler/testData/cli/jvm/signatureClash.kt: (26, 22) Parameter 'c' is never used
 ERROR: compiler/testData/cli/jvm/signatureClash.kt: (6, 5) Accidental override: The following declarations have the same JVM signature (getX()I):
     fun getX(): kotlin.Int
     fun <get-x>(): kotlin.Int
@@ -20,10 +20,10 @@ ERROR: compiler/testData/cli/jvm/signatureClash.kt: (19, 7) Platform declaration
 ERROR: compiler/testData/cli/jvm/signatureClash.kt: (20, 5) Platform declaration clash: The following declarations have the same JVM signature (getTr()I):
     fun <get-tr>(): kotlin.Int
     fun getTr(): kotlin.Int
-ERROR: compiler/testData/cli/jvm/signatureClash.kt: (24, 7) Platform declaration clash: The following declarations have the same JVM signature (f$b$0(LC;)V):
-    fun `f$b$0`(c: C): kotlin.Unit
+ERROR: compiler/testData/cli/jvm/signatureClash.kt: (24, 7) Platform declaration clash: The following declarations have the same JVM signature (access$f$0(LC;)V):
+    fun `access$f$0`(c: C): kotlin.Unit
     fun f(): kotlin.Unit
-ERROR: compiler/testData/cli/jvm/signatureClash.kt: (26, 5) Platform declaration clash: The following declarations have the same JVM signature (f$b$0(LC;)V):
-    fun `f$b$0`(c: C): kotlin.Unit
+ERROR: compiler/testData/cli/jvm/signatureClash.kt: (26, 5) Platform declaration clash: The following declarations have the same JVM signature (access$f$0(LC;)V):
+    fun `access$f$0`(c: C): kotlin.Unit
     fun f(): kotlin.Unit
 COMPILATION_ERROR

compiler/testData/cli/jvm/syntheticAccessorSignatureClash.kt

@@ -1,14 +1,14 @@
 open class Base {
-    open fun `foo$b$0`(d: Derived) {}
+    open fun `access$foo$0`(d: Derived) {}
 
-    open fun `getBar$b$1`(d: Derived): Int = 1
-    open fun `setBar$b$1`(d: Derived, i: Int) {}
+    open fun `access$getBar$1`(d: Derived): Int = 1
+    open fun `access$setBar$1`(d: Derived, i: Int) {}
 
-    open fun `getBaz$b$2`(d: Derived): Int = 1
+    open fun `access$getBaz$2`(d: Derived): Int = 1
 
-    open fun `getBoo$b$3`(d: Derived): Int = 1
+    open fun `access$getBoo$3`(d: Derived): Int = 1
 
-    open fun `setBar1$b$4`(d: Derived, i: Int) {}
+    open fun `access$setBar1$4`(d: Derived, i: Int) {}
 }
 
 class Derived : Base() {

compiler/testData/cli/jvm/syntheticAccessorSignatureClash.out

@@ -1,20 +1,20 @@
 WARNING: compiler/testData/cli/jvm/syntheticAccessorSignatureClash.kt: (34, 17) Variable 's' is never used
-ERROR: compiler/testData/cli/jvm/syntheticAccessorSignatureClash.kt: (15, 5) Accidental override: The following declarations have the same JVM signature (foo$b$0(LDerived;)V):
-    fun `foo$b$0`(d: Derived): kotlin.Unit
+ERROR: compiler/testData/cli/jvm/syntheticAccessorSignatureClash.kt: (15, 5) Accidental override: The following declarations have the same JVM signature (access$foo$0(LDerived;)V):
+    fun `access$foo$0`(d: Derived): kotlin.Unit
     fun foo(): kotlin.Unit
-ERROR: compiler/testData/cli/jvm/syntheticAccessorSignatureClash.kt: (18, 9) Accidental override: The following declarations have the same JVM signature (getBar$b$1(LDerived;)I):
-    fun `getBar$b$1`(d: Derived): kotlin.Int
+ERROR: compiler/testData/cli/jvm/syntheticAccessorSignatureClash.kt: (18, 9) Accidental override: The following declarations have the same JVM signature (access$getBar$1(LDerived;)I):
+    fun `access$getBar$1`(d: Derived): kotlin.Int
     fun <get-bar>(): kotlin.Int
-ERROR: compiler/testData/cli/jvm/syntheticAccessorSignatureClash.kt: (19, 9) Accidental override: The following declarations have the same JVM signature (setBar$b$1(LDerived;I)V):
-    fun `setBar$b$1`(d: Derived, i: kotlin.Int): kotlin.Unit
+ERROR: compiler/testData/cli/jvm/syntheticAccessorSignatureClash.kt: (19, 9) Accidental override: The following declarations have the same JVM signature (access$setBar$1(LDerived;I)V):
+    fun `access$setBar$1`(d: Derived, i: kotlin.Int): kotlin.Unit
     fun <set-bar>(<set-?>: kotlin.Int): kotlin.Unit
-ERROR: compiler/testData/cli/jvm/syntheticAccessorSignatureClash.kt: (21, 5) Accidental override: The following declarations have the same JVM signature (getBaz$b$2(LDerived;)I):
-    fun `getBaz$b$2`(d: Derived): kotlin.Int
+ERROR: compiler/testData/cli/jvm/syntheticAccessorSignatureClash.kt: (21, 5) Accidental override: The following declarations have the same JVM signature (access$getBaz$2(LDerived;)I):
+    fun `access$getBaz$2`(d: Derived): kotlin.Int
     fun <get-baz>(): kotlin.Int
-ERROR: compiler/testData/cli/jvm/syntheticAccessorSignatureClash.kt: (23, 5) Accidental override: The following declarations have the same JVM signature (getBoo$b$3(LDerived;)I):
-    fun `getBoo$b$3`(d: Derived): kotlin.Int
+ERROR: compiler/testData/cli/jvm/syntheticAccessorSignatureClash.kt: (23, 5) Accidental override: The following declarations have the same JVM signature (access$getBoo$3(LDerived;)I):
+    fun `access$getBoo$3`(d: Derived): kotlin.Int
     fun <get-boo>(): kotlin.Int
-ERROR: compiler/testData/cli/jvm/syntheticAccessorSignatureClash.kt: (27, 9) Accidental override: The following declarations have the same JVM signature (setBar1$b$4(LDerived;I)V):
-    fun `setBar1$b$4`(d: Derived, i: kotlin.Int): kotlin.Unit
+ERROR: compiler/testData/cli/jvm/syntheticAccessorSignatureClash.kt: (27, 9) Accidental override: The following declarations have the same JVM signature (access$setBar1$4(LDerived;I)V):
+    fun `access$setBar1$4`(d: Derived, i: kotlin.Int): kotlin.Unit
     fun <set-bar1>(<set-?>: kotlin.Int): kotlin.Unit
 COMPILATION_ERROR

compiler/testData/codegen/boxWithStdlib/synthetic/syntheticAccessorNames.kt

@@ -0,0 +1,48 @@
+// This test checks that synthetic accessors generated by Kotlin compiler have names starting with "access$"
+// This is crucial for some JVM frameworks like Quasar which rely on the bytecode being similar to the one generated by javac
+// See https://youtrack.jetbrains.com/issue/KT-6870
+
+class PrivateConstructor private() {
+    class Nested { val a = PrivateConstructor() }
+}
+
+class PrivatePropertyGet {
+    private val x = 42
+
+    inner class Inner { val a = x }
+}
+
+class PrivatePropertySet {
+    private var x = "a"
+
+    inner class Inner { { x = "b" } }
+}
+
+class PrivateMethod {
+    private fun foo() = ""
+
+    inner class Inner { val a = foo() }
+}
+
+fun check(klass: Class<*>) {
+    for (method in klass.getDeclaredMethods()) {
+        if (method.isSynthetic() && method.getName().startsWith("access$")) return
+    }
+
+    throw AssertionError("No synthetic methods starting with 'access$' found in class $klass")
+}
+
+fun box(): String {
+    check(javaClass<PrivateConstructor>())
+    check(javaClass<PrivatePropertyGet>())
+    check(javaClass<PrivatePropertySet>())
+    check(javaClass<PrivateMethod>())
+
+    // Also check that synthetic accessors really work
+    PrivateConstructor.Nested()
+    PrivatePropertyGet().Inner()
+    PrivatePropertySet().Inner()
+    PrivateMethod().Inner()
+
+    return "OK"
+}

compiler/testData/codegen/bytecodeText/staticFields/classObjectSyntheticAccessor.kt

@@ -5,4 +5,4 @@ class A {
 }
 // A and class object constructor call
 // 2 ALOAD 0
-// 1 synthetic getR
+// 1 synthetic access\$getR