FIR DFA: generate more correct implications on as/as?

^KT-54851 Fixed

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/dfa/FirDataFlowAnalyzer.kt

@@ -446,22 +446,27 @@ abstract class FirDataFlowAnalyzer<FLOW : Flow>(
                 if (operandVariable.isReal()) {
                     flow.addTypeStatement(operandVariable typeEq type)
                 }
-                logicSystem.approveStatementsInsideFlow(
-                    flow,
-                    operandVariable notEq null,
-                    shouldRemoveSynthetics = true,
-                    shouldForkFlow = false
-                )
+                if (!type.canBeNull) {
+                    logicSystem.approveStatementsInsideFlow(
+                        flow,
+                        operandVariable notEq null,
+                        shouldRemoveSynthetics = true,
+                        shouldForkFlow = false
+                    )
+                } else {
+                    val expressionVariable = variableStorage.createSyntheticVariable(typeOperatorCall)
+                    flow.addImplication((expressionVariable notEq null) implies (operandVariable notEq null))
+                }
             }
 
             FirOperation.SAFE_AS -> {
                 val expressionVariable = variableStorage.createSyntheticVariable(typeOperatorCall)
+                flow.addImplication((expressionVariable notEq null) implies (operandVariable notEq null))
                 if (operandVariable.isReal()) {
                     flow.addImplication((expressionVariable notEq null) implies (operandVariable typeEq type))
-                    flow.addImplication((expressionVariable eq null) implies (operandVariable typeNotEq type))
-                }
-                if (type.nullability == ConeNullability.NOT_NULL) {
-                    flow.addImplication((expressionVariable notEq null) implies (operandVariable notEq null))
+                    if (!type.canBeNull) {
+                        flow.addImplication((expressionVariable eq null) implies (operandVariable typeNotEq type))
+                    }
                 }
             }
 

compiler/tests-spec/testData/diagnostics/notLinked/dfa/pos/31.fir.kt

@@ -38,11 +38,11 @@ fun case_2(x: Class?) {
  */
 fun case_3(x: Any?) {
     if ((x as Class?)?.prop_8?.prop_8?.prop_8?.prop_8 == null) else {
-        <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Any? & Class?")!>x<!>
-        <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Any? & Class?")!>x<!><!UNSAFE_CALL!>.<!>prop_8
-        <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Any? & Class?")!>x<!><!UNSAFE_CALL!>.<!>prop_8<!UNSAFE_CALL!>.<!>prop_8
-        <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Any? & Class?")!>x<!><!UNSAFE_CALL!>.<!>prop_8<!UNSAFE_CALL!>.<!>prop_8<!UNSAFE_CALL!>.<!>prop_8
-        <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Any? & Class?")!>x<!><!UNSAFE_CALL!>.<!>prop_8<!UNSAFE_CALL!>.<!>prop_8<!UNSAFE_CALL!>.<!>prop_8<!UNSAFE_CALL!>.<!>prop_8<!UNSAFE_CALL!>.<!>prop_8
+        <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Any? & Class")!>x<!>
+        <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Any? & Class")!>x<!>.prop_8
+        <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Any? & Class")!>x<!>.prop_8<!UNSAFE_CALL!>.<!>prop_8
+        <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Any? & Class")!>x<!>.prop_8<!UNSAFE_CALL!>.<!>prop_8<!UNSAFE_CALL!>.<!>prop_8
+        <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Any? & Class")!>x<!>.prop_8<!UNSAFE_CALL!>.<!>prop_8<!UNSAFE_CALL!>.<!>prop_8<!UNSAFE_CALL!>.<!>prop_8<!UNSAFE_CALL!>.<!>prop_8
     }
 }
 
@@ -87,7 +87,7 @@ fun case_6(x: Class?) {
         <!DEBUG_INFO_EXPRESSION_TYPE("Class? & Class")!>x<!>.prop_8
         <!DEBUG_INFO_EXPRESSION_TYPE("Class? & Class")!>x<!>.prop_8.prop_8
         <!DEBUG_INFO_EXPRESSION_TYPE("Class? & Class")!>x<!>.prop_8.prop_8.prop_8
-        <!DEBUG_INFO_EXPRESSION_TYPE("Class? & Class")!>x<!>.prop_8.prop_8.prop_8<!UNSAFE_CALL!>.<!>prop_8<!UNSAFE_CALL!>.<!>prop_8
+        <!DEBUG_INFO_EXPRESSION_TYPE("Class? & Class")!>x<!>.prop_8.prop_8.prop_8.prop_8<!UNSAFE_CALL!>.<!>prop_8
     }
 }
 

compiler/tests-spec/testData/diagnostics/notLinked/dfa/pos/40.fir.kt

@@ -120,8 +120,8 @@ fun case_12(x: Any?) {
  */
 fun case_13(x: Any?) {
     if (x as Boolean? ?: x!!) {
-        <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Any? & kotlin.Boolean?")!>x<!><!UNSAFE_CALL!>.<!>not()
-        <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Boolean?")!>select(x)<!><!UNSAFE_CALL!>.<!>not()
+        <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Any? & kotlin.Boolean")!>x<!>.not()
+        <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Boolean")!>select(x)<!>.not()
     }
 }
 

compiler/tests-spec/testData/diagnostics/notLinked/dfa/pos/68.fir.kt

@@ -20,24 +20,24 @@ fun case_2(x: Any?) {
 // TESTCASE NUMBER: 3
 fun case_3(x: Any?) {
     if (x as Number? is Int) {
-        <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Any? & kotlin.Number?")!>x<!>
-        <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Any? & kotlin.Number?")!>x<!>.<!UNRESOLVED_REFERENCE!>inv<!>()
+        <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Any? & kotlin.Number")!>x<!>
+        <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Any? & kotlin.Number")!>x<!>.<!UNRESOLVED_REFERENCE!>inv<!>()
     }
 }
 
 // TESTCASE NUMBER: 4
 fun case_4(x: Any?) {
     if (x as Class? is Class) {
-        <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Any? & Class?")!>x<!>
-        <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Any? & Class?")!>x<!><!UNSAFE_CALL!>.<!>prop_1
+        <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Any? & Class")!>x<!>
+        <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Any? & Class")!>x<!><!UNSAFE_CALL{LT}!>.<!>prop_1
     }
 }
 
 // TESTCASE NUMBER: 5
 fun case_5(x: Any?) {
     if (x as Nothing? is Nothing) {
-        <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Any? & kotlin.Nothing?")!>x<!>
-        <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Any? & kotlin.Nothing?")!>x<!><!UNSAFE_CALL!>.<!><!UNRESOLVED_REFERENCE{LT}!>inv<!>()
+        <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Any? & kotlin.Nothing")!>x<!>
+        <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Any? & kotlin.Nothing")!>x<!><!UNSAFE_CALL{LT}!>.<!><!UNRESOLVED_REFERENCE{LT}!>inv<!>()
     }
 }
 
@@ -51,8 +51,8 @@ fun case_6(x: Any?) {
 // TESTCASE NUMBER: 7
 fun case_7(x: Any?) {
     if (x as String? != null) {
-        <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Any? & kotlin.String?")!>x<!>
-        <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Any? & kotlin.String?")!>x<!><!UNSAFE_CALL!>.<!>length
+        <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Any? & kotlin.String")!>x<!>
+        <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Any? & kotlin.String")!>x<!><!UNSAFE_CALL{LT}!>.<!>length
     }
 }
 

compiler/tests-spec/testData/diagnostics/notLinked/dfa/pos/69.fir.kt

@@ -19,8 +19,8 @@ fun case_2(x: Any?) {
 // TESTCASE NUMBER: 3
 fun case_3(x: Any?) {
     if (x as ClassLevel1? is ClassLevel1) {
-        <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Any? & ClassLevel1?")!>x<!>
-        <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Any? & ClassLevel1?")!>x<!><!UNSAFE_CALL!>.<!>test1()
+        <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Any? & ClassLevel1")!>x<!>
+        <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Any? & ClassLevel1")!>x<!>.test1()
     }
 }