[FIR] Support PreliminaryLoopVisitor in FIR DFA

compiler/testData/codegen/box/regressions/kt41806.kt

@@ -1,6 +1,5 @@
 // TARGET_BACKEND: JVM
 // WITH_RUNTIME
-// IGNORE_BACKEND_FIR: JVM_IR
 
 open class A {
     fun Foo() {
@@ -23,4 +22,4 @@ fun box(): String {
     test.Foo()
 
     return "OK"
-}
+}

compiler/testData/codegen/box/smartCasts/kt44804.kt

@@ -0,0 +1,43 @@
+// ISSUE: KT-44804
+// WITH_STDLIB
+
+abstract class AbstractInsnNode(val next: AbstractInsnNode? = null)
+
+class LineNumberNode(next: AbstractInsnNode? = null) : AbstractInsnNode(next) {
+    val line: Int = 1
+}
+
+class LabelNode() : AbstractInsnNode(null)
+
+fun isDeadLineNumber(insn: LineNumberNode, index: Int, frames: Array<out Any?>): Boolean {
+    // Line number node is "dead" if the corresponding line number interval
+    // contains at least one "dead" meaningful instruction and no "live" meaningful instructions.
+    var finger: AbstractInsnNode = insn
+    var fingerIndex = index
+    var hasDeadInsn = false
+    loop@ while (true) {
+        finger = finger.next ?: break
+        fingerIndex++
+        when (finger) {
+            is LabelNode ->
+                continue@loop
+            is LineNumberNode ->
+                if (finger.line != insn.line) return hasDeadInsn
+            else -> {
+                if (frames[fingerIndex] != null) return false
+                hasDeadInsn = true
+            }
+        }
+    }
+    return true
+}
+
+fun box(): String {
+    val node = LineNumberNode(
+        LineNumberNode(
+            LabelNode()
+        )
+    )
+    val result = isDeadLineNumber(node, 0, arrayOf(null, null, "aaa", "bbb"))
+    return if (result) "OK" else "fail"
+}

compiler/testData/diagnostics/tests/smartCasts/lambdaAndArgumentFun.fir.kt

@@ -10,5 +10,5 @@ fun use() {
     // Write to x is AFTER
     x.hashCode()
     // No smart cast should be here!
-    foo(bar { x = null }, x.hashCode())
+    foo(bar { x = null }, x<!UNSAFE_CALL!>.<!>hashCode())
 }

compiler/testData/diagnostics/tests/smartCasts/ownerDeclaresBothModifies.fir.kt

@@ -4,10 +4,10 @@ fun foo(arg: Int?) {
     if (x == null) return
     run {
         // Unsafe because of owner modification
-        x.hashCode()
+        x<!UNSAFE_CALL!>.<!>hashCode()
         x = null
     }
     if (x != null) x = 42
     // Unsafe because of lambda
     x<!UNSAFE_CALL!>.<!>hashCode()
-}
+}

compiler/testData/diagnostics/tests/smartCasts/variables/lambdaBetweenArguments.fir.kt

@@ -6,5 +6,5 @@ fun foo(x: Int, f: () -> Unit, y: Int) {}
 fun bar() {
     var x: Int?
     x = 4
-    foo(x, { x = null; x<!UNSAFE_CALL!>.<!>hashCode() }, x)
+    <!INAPPLICABLE_CANDIDATE!>foo<!>(x, { x = null; x<!UNSAFE_CALL!>.<!>hashCode() }, x)
 }

compiler/testData/diagnostics/tests/smartCasts/variables/varChangedInLoop.fir.kt

@@ -2,8 +2,8 @@ public fun foo() {
     var i: Any = 1
     if (i is Int) {
         while (i != 10) {
-            i++      // Here smart cast should not be performed due to a successor
+            i<!UNRESOLVED_REFERENCE!>++<!>      // Here smart cast should not be performed due to a successor
             i = ""
         }
     }
-}
+}

compiler/testData/diagnostics/tests/smartCasts/variables/varNotChangedInLoop.fir.kt

@@ -2,7 +2,7 @@ public fun foo() {
     var i: Any = 1
     if (i is Int) {
         while (i != 10) {
-            i++
+            i<!UNRESOLVED_REFERENCE!>++<!>
         }
     }
-}
+}

compiler/testData/diagnostics/tests/smartCasts/variables/whileWithBreak.fir.kt

@@ -13,5 +13,5 @@ fun list(start: String) {
         e = e.next()
     }
     // e can never be null but we do not know it
-    e.hashCode()
-}
+    e<!UNSAFE_CALL!>.<!>hashCode()
+}

compiler/testData/diagnostics/tests/smartCasts/varnotnull/assignNestedWhile.fir.kt

@@ -13,7 +13,7 @@ fun foo(): Bar {
     y = Bar()
     while (x != null) {
         // Here call is unsafe because of inner loop
-        y.next()
+        y<!UNSAFE_CALL!>.<!>next()
         while (y != null) {
             if (x == y)
                 // x is not null because of outer while
@@ -25,4 +25,4 @@ fun foo(): Bar {
         x = x.next()
     }
     return Bar()
-}
+}

compiler/testData/diagnostics/tests/smartCasts/varnotnull/capturedInClosureModifiedBefore.fir.kt

@@ -30,7 +30,7 @@ fun baz(s: String?) {
             x.hashCode()
         }
         run {
-            x.hashCode()
+            x<!UNSAFE_CALL!>.<!>hashCode()
             x = null
         }
     }
@@ -40,11 +40,11 @@ fun gaz(s: String?) {
     var x = s
     if (x != null) {
         run {
-            x.hashCode()
+            x<!UNSAFE_CALL!>.<!>hashCode()
             x = null
         }
         run {
-            x.hashCode()
+            x<!UNSAFE_CALL!>.<!>hashCode()
         }
     }
 }
@@ -57,4 +57,4 @@ fun gav(s: String?) {
         }
         x = null
     }
-}
+}

compiler/testData/diagnostics/tests/smartCasts/varnotnull/doWhileWithBreak.fir.kt

@@ -1,21 +0,0 @@
-data class SomeObject(val n: SomeObject?) {
-    fun doSomething(): Boolean = true
-    fun next(): SomeObject? = n    
-}
-
-
-fun list(start: SomeObject) {
-    var e: SomeObject?
-    e = start
-    do {
-        // In theory smart cast is possible here
-        // But in practice we have a loop with changing e
-        // ?: should we "or" entrance type info with condition type info?
-        if (!e.doSomething())
-            break
-        // Smart cast here is still not possible
-        e = e.next()
-    } while (e != null)
-    // e can be null because of next()
-    e.doSomething()
-}

compiler/testData/diagnostics/tests/smartCasts/varnotnull/doWhileWithBreak.kt

@@ -1,3 +1,4 @@
+// FIR_IDENTICAL
 data class SomeObject(val n: SomeObject?) {
     fun doSomething(): Boolean = true
     fun next(): SomeObject? = n    

compiler/testData/diagnostics/tests/smartCasts/varnotnull/doWhileWithMiddleBreak.fir.kt

@@ -1,12 +0,0 @@
-fun x(): Boolean { return true }
-
-public fun foo(pp: String?): Int {
-    var p = pp
-    do {
-        p!!.length
-        if (p == "abc") break
-        p = null
-    } while (!x())
-    // Smart cast is NOT possible here
-    return p.length
-}

compiler/testData/diagnostics/tests/smartCasts/varnotnull/doWhileWithMiddleBreak.kt

@@ -1,3 +1,4 @@
+// FIR_IDENTICAL
 fun x(): Boolean { return true }
 
 public fun foo(pp: String?): Int {

compiler/testData/diagnostics/tests/smartCasts/varnotnull/forEach.fir.kt

@@ -9,9 +9,9 @@ fun list(start: SomeObject): SomeObject {
     var e: SomeObject? = start
     for (i in 0..42) {
         // Unsafe calls because of nullable e at the beginning
-        e.doSomething()
-        e = e.next()
+        e<!UNSAFE_CALL!>.<!>doSomething()
+        e = e<!UNSAFE_CALL!>.<!>next()
     }
     // Smart cast is not possible here due to next()
     return e
-}
+}

compiler/testData/diagnostics/tests/smartCasts/varnotnull/infiniteWhileWithBreak.fir.kt

@@ -16,5 +16,5 @@ fun list(start: SomeObject) {
         e = e.next()
     } 
     // e can be null because of next()
-    e.doSomething()
-}
+    e<!UNSAFE_CALL!>.<!>doSomething()
+}

compiler/testData/diagnostics/tests/smartCasts/varnotnull/varChangedInLoop.fir.kt

@@ -2,8 +2,8 @@ public fun foo() {
     var i: Int? = 1
     if (i != null) {
         while (i != 10) {
-            i++      // Here smart cast should not be performed due to a successor
+            i<!UNSAFE_CALL!>++<!>      // Here smart cast should not be performed due to a successor
             i = null
         }
     }
-}
+}

compiler/testData/diagnostics/tests/smartCasts/varnotnull/varNotChangedInLoop.fir.kt

@@ -2,7 +2,7 @@ public fun foo() {
     var i: Int? = 1
     if (i != null) {
         while (i != 10) {
-            i++
+            i<!UNSAFE_CALL!>++<!>
         }
     }
-}
+}

compiler/testData/diagnostics/tests/smartCasts/varnotnull/whileWithBreak.fir.kt

@@ -13,5 +13,5 @@ fun list(start: SomeObject) {
         e = e.next()
     }
     // e can be null because of next()
-    e.doSomething()
-}
+    e<!UNSAFE_CALL!>.<!>doSomething()
+}