diff --git a/compiler/fir/analysis-tests/testData/resolveWithStdlib/diagnostics/forLoopChecker.kt b/compiler/fir/analysis-tests/testData/resolveWithStdlib/diagnostics/forLoopChecker.kt
index 24cdb140ab5..658e51e708a 100644
--- a/compiler/fir/analysis-tests/testData/resolveWithStdlib/diagnostics/forLoopChecker.kt
+++ b/compiler/fir/analysis-tests/testData/resolveWithStdlib/diagnostics/forLoopChecker.kt
@@ -101,9 +101,9 @@ fun test(
     for (i in <!HAS_NEXT_MISSING, NEXT_MISSING!>notRange2<!>);
     for (i in <!NEXT_MISSING!>notRange3<!>);
     for (i in <!HAS_NEXT_MISSING!>notRange4<!>);
-    for (i in notRange5);
+    <!CONDITION_TYPE_MISMATCH!>for (i in notRange5)<!>;
     for (i in notRange6);
-    for (i in notRange7);
+    <!CONDITION_TYPE_MISMATCH!>for (i in notRange7)<!>;
     for (i in <!HAS_NEXT_MISSING!>notRange8<!>);
     for (i in <!OPERATOR_MODIFIER_REQUIRED, OPERATOR_MODIFIER_REQUIRED, OPERATOR_MODIFIER_REQUIRED!>notRange9<!>);
     for (i in range0);
diff --git a/compiler/fir/checkers/checkers-component-generator/src/org/jetbrains/kotlin/fir/checkers/generator/Main.kt b/compiler/fir/checkers/checkers-component-generator/src/org/jetbrains/kotlin/fir/checkers/generator/Main.kt
index 29c9a309f4c..e9ea2e8ff84 100644
--- a/compiler/fir/checkers/checkers-component-generator/src/org/jetbrains/kotlin/fir/checkers/generator/Main.kt
+++ b/compiler/fir/checkers/checkers-component-generator/src/org/jetbrains/kotlin/fir/checkers/generator/Main.kt
@@ -28,6 +28,8 @@ fun main(args: Array<String>) {
         alias<FirVariableAssignment>("VariableAssignmentChecker")
         alias<FirTryExpression>("TryExpressionChecker")
         alias<FirWhenExpression>("WhenExpressionChecker")
+        alias<FirLoop>("LoopExpressionChecker")
+        alias<FirBinaryLogicExpression>("LogicExpressionChecker")
         alias<FirReturnExpression>("ReturnExpressionChecker")
         alias<FirBlock>("BlockChecker")
         alias<FirAnnotationCall>("AnnotationCallChecker")
diff --git a/compiler/fir/checkers/gen/org/jetbrains/kotlin/fir/analysis/checkers/expression/ComposedExpressionCheckers.kt b/compiler/fir/checkers/gen/org/jetbrains/kotlin/fir/analysis/checkers/expression/ComposedExpressionCheckers.kt
index 494a6aea306..d4cfbf10f69 100644
--- a/compiler/fir/checkers/gen/org/jetbrains/kotlin/fir/analysis/checkers/expression/ComposedExpressionCheckers.kt
+++ b/compiler/fir/checkers/gen/org/jetbrains/kotlin/fir/analysis/checkers/expression/ComposedExpressionCheckers.kt
@@ -25,6 +25,10 @@ class ComposedExpressionCheckers : ExpressionCheckers() {
         get() = _tryExpressionCheckers
     override val whenExpressionCheckers: Set<FirWhenExpressionChecker>
         get() = _whenExpressionCheckers
+    override val loopExpressionCheckers: Set<FirLoopExpressionChecker>
+        get() = _loopExpressionCheckers
+    override val logicExpressionCheckers: Set<FirLogicExpressionChecker>
+        get() = _logicExpressionCheckers
     override val returnExpressionCheckers: Set<FirReturnExpressionChecker>
         get() = _returnExpressionCheckers
     override val blockCheckers: Set<FirBlockChecker>
@@ -56,6 +60,8 @@ class ComposedExpressionCheckers : ExpressionCheckers() {
     private val _variableAssignmentCheckers: MutableSet<FirVariableAssignmentChecker> = mutableSetOf()
     private val _tryExpressionCheckers: MutableSet<FirTryExpressionChecker> = mutableSetOf()
     private val _whenExpressionCheckers: MutableSet<FirWhenExpressionChecker> = mutableSetOf()
+    private val _loopExpressionCheckers: MutableSet<FirLoopExpressionChecker> = mutableSetOf()
+    private val _logicExpressionCheckers: MutableSet<FirLogicExpressionChecker> = mutableSetOf()
     private val _returnExpressionCheckers: MutableSet<FirReturnExpressionChecker> = mutableSetOf()
     private val _blockCheckers: MutableSet<FirBlockChecker> = mutableSetOf()
     private val _annotationCallCheckers: MutableSet<FirAnnotationCallChecker> = mutableSetOf()
@@ -77,6 +83,8 @@ class ComposedExpressionCheckers : ExpressionCheckers() {
         _variableAssignmentCheckers += checkers.variableAssignmentCheckers
         _tryExpressionCheckers += checkers.tryExpressionCheckers
         _whenExpressionCheckers += checkers.whenExpressionCheckers
+        _loopExpressionCheckers += checkers.loopExpressionCheckers
+        _logicExpressionCheckers += checkers.logicExpressionCheckers
         _returnExpressionCheckers += checkers.returnExpressionCheckers
         _blockCheckers += checkers.blockCheckers
         _annotationCallCheckers += checkers.annotationCallCheckers
diff --git a/compiler/fir/checkers/gen/org/jetbrains/kotlin/fir/analysis/checkers/expression/ExpressionCheckers.kt b/compiler/fir/checkers/gen/org/jetbrains/kotlin/fir/analysis/checkers/expression/ExpressionCheckers.kt
index db1cb7eb3a5..407b36f74e9 100644
--- a/compiler/fir/checkers/gen/org/jetbrains/kotlin/fir/analysis/checkers/expression/ExpressionCheckers.kt
+++ b/compiler/fir/checkers/gen/org/jetbrains/kotlin/fir/analysis/checkers/expression/ExpressionCheckers.kt
@@ -23,6 +23,8 @@ abstract class ExpressionCheckers {
     open val variableAssignmentCheckers: Set<FirVariableAssignmentChecker> = emptySet()
     open val tryExpressionCheckers: Set<FirTryExpressionChecker> = emptySet()
     open val whenExpressionCheckers: Set<FirWhenExpressionChecker> = emptySet()
+    open val loopExpressionCheckers: Set<FirLoopExpressionChecker> = emptySet()
+    open val logicExpressionCheckers: Set<FirLogicExpressionChecker> = emptySet()
     open val returnExpressionCheckers: Set<FirReturnExpressionChecker> = emptySet()
     open val blockCheckers: Set<FirBlockChecker> = emptySet()
     open val annotationCallCheckers: Set<FirAnnotationCallChecker> = emptySet()
@@ -42,6 +44,8 @@ abstract class ExpressionCheckers {
     @CheckersComponentInternal internal val allVariableAssignmentCheckers: Set<FirVariableAssignmentChecker> get() = variableAssignmentCheckers + basicExpressionCheckers
     @CheckersComponentInternal internal val allTryExpressionCheckers: Set<FirTryExpressionChecker> get() = tryExpressionCheckers + basicExpressionCheckers
     @CheckersComponentInternal internal val allWhenExpressionCheckers: Set<FirWhenExpressionChecker> get() = whenExpressionCheckers + basicExpressionCheckers
+    @CheckersComponentInternal internal val allLoopExpressionCheckers: Set<FirLoopExpressionChecker> get() = loopExpressionCheckers + basicExpressionCheckers
+    @CheckersComponentInternal internal val allLogicExpressionCheckers: Set<FirLogicExpressionChecker> get() = logicExpressionCheckers + basicExpressionCheckers
     @CheckersComponentInternal internal val allReturnExpressionCheckers: Set<FirReturnExpressionChecker> get() = returnExpressionCheckers + basicExpressionCheckers
     @CheckersComponentInternal internal val allBlockCheckers: Set<FirBlockChecker> get() = blockCheckers + basicExpressionCheckers
     @CheckersComponentInternal internal val allAnnotationCallCheckers: Set<FirAnnotationCallChecker> get() = annotationCallCheckers + basicExpressionCheckers
diff --git a/compiler/fir/checkers/gen/org/jetbrains/kotlin/fir/analysis/checkers/expression/FirExpressionCheckerAliases.kt b/compiler/fir/checkers/gen/org/jetbrains/kotlin/fir/analysis/checkers/expression/FirExpressionCheckerAliases.kt
index 18a4fba256d..4dd35550f97 100644
--- a/compiler/fir/checkers/gen/org/jetbrains/kotlin/fir/analysis/checkers/expression/FirExpressionCheckerAliases.kt
+++ b/compiler/fir/checkers/gen/org/jetbrains/kotlin/fir/analysis/checkers/expression/FirExpressionCheckerAliases.kt
@@ -12,12 +12,14 @@ package org.jetbrains.kotlin.fir.analysis.checkers.expression
 
 import org.jetbrains.kotlin.fir.declarations.FirAnonymousFunction
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
+import org.jetbrains.kotlin.fir.expressions.FirBinaryLogicExpression
 import org.jetbrains.kotlin.fir.expressions.FirBlock
 import org.jetbrains.kotlin.fir.expressions.FirCheckNotNullCall
 import org.jetbrains.kotlin.fir.expressions.FirElvisExpression
 import org.jetbrains.kotlin.fir.expressions.FirEqualityOperatorCall
 import org.jetbrains.kotlin.fir.expressions.FirFunctionCall
 import org.jetbrains.kotlin.fir.expressions.FirGetClassCall
+import org.jetbrains.kotlin.fir.expressions.FirLoop
 import org.jetbrains.kotlin.fir.expressions.FirQualifiedAccessExpression
 import org.jetbrains.kotlin.fir.expressions.FirResolvedQualifier
 import org.jetbrains.kotlin.fir.expressions.FirReturnExpression
@@ -35,6 +37,8 @@ typealias FirFunctionCallChecker = FirExpressionChecker<FirFunctionCall>
 typealias FirVariableAssignmentChecker = FirExpressionChecker<FirVariableAssignment>
 typealias FirTryExpressionChecker = FirExpressionChecker<FirTryExpression>
 typealias FirWhenExpressionChecker = FirExpressionChecker<FirWhenExpression>
+typealias FirLoopExpressionChecker = FirExpressionChecker<FirLoop>
+typealias FirLogicExpressionChecker = FirExpressionChecker<FirBinaryLogicExpression>
 typealias FirReturnExpressionChecker = FirExpressionChecker<FirReturnExpression>
 typealias FirBlockChecker = FirExpressionChecker<FirBlock>
 typealias FirAnnotationCallChecker = FirExpressionChecker<FirAnnotationCall>
diff --git a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/checkers/FirHelpers.kt b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/checkers/FirHelpers.kt
index 7afd0371317..8e88d2de75d 100644
--- a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/checkers/FirHelpers.kt
+++ b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/checkers/FirHelpers.kt
@@ -568,4 +568,13 @@ fun checkTypeMismatch(
             reporter.report(diagnosticFactory.on(source, lValueType, rValueType), context)
         }
     }
-}
\ No newline at end of file
+}
+
+internal fun checkCondition(condition: FirExpression, context: CheckerContext, reporter: DiagnosticReporter) {
+    val coneType = condition.typeRef.coneType.lowerBoundIfFlexible()
+    if (coneType !is ConeKotlinErrorType &&
+        !coneType.isSubtypeOf(context.session.typeContext, context.session.builtinTypes.booleanType.type)
+    ) {
+        reporter.reportOn(condition.source, FirErrors.CONDITION_TYPE_MISMATCH, coneType, context)
+    }
+}
diff --git a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/checkers/expression/FirLogicExpressionTypeChecker.kt b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/checkers/expression/FirLogicExpressionTypeChecker.kt
new file mode 100644
index 00000000000..1006eac3f49
--- /dev/null
+++ b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/checkers/expression/FirLogicExpressionTypeChecker.kt
@@ -0,0 +1,18 @@
+/*
+ * Copyright 2010-2021 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.fir.analysis.checkers.expression
+
+import org.jetbrains.kotlin.fir.analysis.checkers.checkCondition
+import org.jetbrains.kotlin.fir.analysis.checkers.context.CheckerContext
+import org.jetbrains.kotlin.fir.analysis.diagnostics.DiagnosticReporter
+import org.jetbrains.kotlin.fir.expressions.FirBinaryLogicExpression
+
+object FirLogicExpressionTypeChecker : FirLogicExpressionChecker() {
+    override fun check(expression: FirBinaryLogicExpression, context: CheckerContext, reporter: DiagnosticReporter) {
+        checkCondition(expression.leftOperand, context, reporter)
+        checkCondition(expression.rightOperand, context, reporter)
+    }
+}
\ No newline at end of file
diff --git a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/checkers/expression/FirLoopConditionChecker.kt b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/checkers/expression/FirLoopConditionChecker.kt
new file mode 100644
index 00000000000..f25c76db2d7
--- /dev/null
+++ b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/checkers/expression/FirLoopConditionChecker.kt
@@ -0,0 +1,23 @@
+/*
+ * Copyright 2010-2021 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.fir.analysis.checkers.expression
+
+import org.jetbrains.kotlin.fir.analysis.checkers.checkCondition
+import org.jetbrains.kotlin.fir.analysis.checkers.context.CheckerContext
+import org.jetbrains.kotlin.fir.analysis.diagnostics.DiagnosticReporter
+import org.jetbrains.kotlin.fir.analysis.diagnostics.withSuppressedDiagnostics
+import org.jetbrains.kotlin.fir.expressions.FirErrorLoop
+import org.jetbrains.kotlin.fir.expressions.FirLoop
+
+object FirLoopConditionChecker : FirLoopExpressionChecker() {
+    override fun check(expression: FirLoop, context: CheckerContext, reporter: DiagnosticReporter) {
+        if (expression is FirErrorLoop) return
+        val condition = expression.condition
+        withSuppressedDiagnostics(condition, context) {
+            checkCondition(condition, context, reporter)
+        }
+    }
+}
diff --git a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/checkers/expression/FirWhenConditionChecker.kt b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/checkers/expression/FirWhenConditionChecker.kt
new file mode 100644
index 00000000000..0bf30b8bb65
--- /dev/null
+++ b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/checkers/expression/FirWhenConditionChecker.kt
@@ -0,0 +1,25 @@
+/*
+ * Copyright 2010-2021 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.fir.analysis.checkers.expression
+
+import org.jetbrains.kotlin.fir.analysis.checkers.checkCondition
+import org.jetbrains.kotlin.fir.analysis.checkers.context.CheckerContext
+import org.jetbrains.kotlin.fir.analysis.diagnostics.DiagnosticReporter
+import org.jetbrains.kotlin.fir.analysis.diagnostics.withSuppressedDiagnostics
+import org.jetbrains.kotlin.fir.expressions.FirWhenExpression
+import org.jetbrains.kotlin.fir.expressions.impl.FirElseIfTrueCondition
+
+object FirWhenConditionChecker : FirWhenExpressionChecker() {
+    override fun check(expression: FirWhenExpression, context: CheckerContext, reporter: DiagnosticReporter) {
+        for (branch in expression.branches) {
+            val condition = branch.condition
+            if (condition is FirElseIfTrueCondition) continue
+            withSuppressedDiagnostics(condition, context) {
+                checkCondition(condition, context, reporter)
+            }
+        }
+    }
+}
\ No newline at end of file
diff --git a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/collectors/components/ExpressionCheckersDiagnosticComponent.kt b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/collectors/components/ExpressionCheckersDiagnosticComponent.kt
index 34aa3c91655..a7bbf90f792 100644
--- a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/collectors/components/ExpressionCheckersDiagnosticComponent.kt
+++ b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/collectors/components/ExpressionCheckersDiagnosticComponent.kt
@@ -11,7 +11,6 @@ import org.jetbrains.kotlin.fir.analysis.checkers.context.CheckerContext
 import org.jetbrains.kotlin.fir.analysis.checkers.expression.ExpressionCheckers
 import org.jetbrains.kotlin.fir.analysis.checkers.expression.FirExpressionChecker
 import org.jetbrains.kotlin.fir.analysis.checkersComponent
-import org.jetbrains.kotlin.fir.analysis.collectors.AbstractDiagnosticCollector
 import org.jetbrains.kotlin.fir.analysis.diagnostics.DiagnosticReporter
 import org.jetbrains.kotlin.fir.declarations.FirAnonymousFunction
 import org.jetbrains.kotlin.fir.expressions.*
@@ -63,8 +62,20 @@ class ExpressionCheckersDiagnosticComponent(
         checkers.allWhenExpressionCheckers.check(whenExpression, data, reporter)
     }
 
+    override fun visitWhileLoop(whileLoop: FirWhileLoop, data: CheckerContext) {
+        checkers.allLoopExpressionCheckers.check(whileLoop, data, reporter)
+    }
+
+    override fun visitDoWhileLoop(doWhileLoop: FirDoWhileLoop, data: CheckerContext) {
+        checkers.allLoopExpressionCheckers.check(doWhileLoop, data, reporter)
+    }
+
+    override fun visitErrorLoop(errorLoop: FirErrorLoop, data: CheckerContext) {
+        checkers.allLoopExpressionCheckers.check(errorLoop, data, reporter)
+    }
+
     override fun visitBinaryLogicExpression(binaryLogicExpression: FirBinaryLogicExpression, data: CheckerContext) {
-        checkers.allBasicExpressionCheckers.check(binaryLogicExpression, data, reporter)
+        checkers.allLogicExpressionCheckers.check(binaryLogicExpression, data, reporter)
     }
 
     override fun visitArrayOfCall(arrayOfCall: FirArrayOfCall, data: CheckerContext) {
diff --git a/compiler/fir/entrypoint/src/org/jetbrains/kotlin/fir/checkers/CommonExpressionCheckers.kt b/compiler/fir/entrypoint/src/org/jetbrains/kotlin/fir/checkers/CommonExpressionCheckers.kt
index a478c46a14d..4f5f86c0a43 100644
--- a/compiler/fir/entrypoint/src/org/jetbrains/kotlin/fir/checkers/CommonExpressionCheckers.kt
+++ b/compiler/fir/entrypoint/src/org/jetbrains/kotlin/fir/checkers/CommonExpressionCheckers.kt
@@ -56,7 +56,18 @@ object CommonExpressionCheckers : ExpressionCheckers() {
 
     override val whenExpressionCheckers: Set<FirWhenExpressionChecker>
         get() = setOf(
-            FirExhaustiveWhenChecker
+            FirExhaustiveWhenChecker,
+            FirWhenConditionChecker,
+        )
+
+    override val loopExpressionCheckers: Set<FirLoopExpressionChecker>
+        get() = setOf(
+            FirLoopConditionChecker,
+        )
+
+    override val logicExpressionCheckers: Set<FirLogicExpressionChecker>
+        get() = setOf(
+            FirLogicExpressionTypeChecker,
         )
 
     override val returnExpressionCheckers: Set<FirReturnExpressionChecker>
diff --git a/compiler/testData/diagnostics/tests/BinaryCallsOnNullableValues.fir.kt b/compiler/testData/diagnostics/tests/BinaryCallsOnNullableValues.fir.kt
index 687dae6a3e3..3086aed6ca3 100644
--- a/compiler/testData/diagnostics/tests/BinaryCallsOnNullableValues.fir.kt
+++ b/compiler/testData/diagnostics/tests/BinaryCallsOnNullableValues.fir.kt
@@ -26,7 +26,7 @@ fun f(): Unit {
     <!ARGUMENT_TYPE_MISMATCH!>x<!> in 1..2
 
     val y : Boolean? = true
-    false || y
-    y && true
-    y && 1
+    false || <!CONDITION_TYPE_MISMATCH!>y<!>
+    <!CONDITION_TYPE_MISMATCH!>y<!> && true
+    <!CONDITION_TYPE_MISMATCH!>y<!> && <!CONDITION_TYPE_MISMATCH!>1<!>
 }
diff --git a/compiler/testData/diagnostics/tests/ForRangeConventions.fir.kt b/compiler/testData/diagnostics/tests/ForRangeConventions.fir.kt
index 1f5ac003d33..4ce159082d3 100644
--- a/compiler/testData/diagnostics/tests/ForRangeConventions.fir.kt
+++ b/compiler/testData/diagnostics/tests/ForRangeConventions.fir.kt
@@ -82,9 +82,9 @@ fun test(notRange1: NotRange1, notRange2: NotRange2, notRange3: NotRange3, notRa
   for (i in <!HAS_NEXT_MISSING, NEXT_MISSING!>notRange2<!>);
   for (i in <!NEXT_MISSING!>notRange3<!>);
   for (i in <!HAS_NEXT_MISSING!>notRange4<!>);
-  for (i in notRange5);
+  <!CONDITION_TYPE_MISMATCH!>for (i in notRange5)<!>;
   for (i in notRange6);
-  for (i in notRange7);
+  <!CONDITION_TYPE_MISMATCH!>for (i in notRange7)<!>;
   for (i in <!HAS_NEXT_MISSING!>notRange8<!>);
   for (i in range0);
   for (i in range1);
diff --git a/compiler/testData/diagnostics/tests/checkArguments/booleanExpressions.fir.kt b/compiler/testData/diagnostics/tests/checkArguments/booleanExpressions.fir.kt
index 4d6dbaa913d..7d0bef6f296 100644
--- a/compiler/testData/diagnostics/tests/checkArguments/booleanExpressions.fir.kt
+++ b/compiler/testData/diagnostics/tests/checkArguments/booleanExpressions.fir.kt
@@ -1,7 +1,7 @@
 // !WITH_NEW_INFERENCE
 fun foo1(b: Boolean, c: Int) {
-    if (b && c) {}
-    if (b || c) {}
-    if (c && b) {}
-    if (c || b) {}
+    if (b && <!CONDITION_TYPE_MISMATCH!>c<!>) {}
+    if (b || <!CONDITION_TYPE_MISMATCH!>c<!>) {}
+    if (<!CONDITION_TYPE_MISMATCH!>c<!> && b) {}
+    if (<!CONDITION_TYPE_MISMATCH!>c<!> || b) {}
 }
diff --git a/compiler/testData/diagnostics/tests/controlStructures/kt657.fir.kt b/compiler/testData/diagnostics/tests/controlStructures/kt657.fir.kt
index 4e9d18ad852..eb6272ee5a2 100644
--- a/compiler/testData/diagnostics/tests/controlStructures/kt657.fir.kt
+++ b/compiler/testData/diagnostics/tests/controlStructures/kt657.fir.kt
@@ -7,10 +7,10 @@ fun foo() =
     when {
         cond1() -> 12
         cond2() -> 2
-        4 -> 34
-        Pair(1, 2) -> 3
+        <!CONDITION_TYPE_MISMATCH!>4<!> -> 34
+        <!CONDITION_TYPE_MISMATCH!>Pair(1, 2)<!> -> 3
         in 1..10 -> 34
-        4 -> 38
+        <!CONDITION_TYPE_MISMATCH!>4<!> -> 38
         is Int -> 33
         else -> 34
     }
diff --git a/compiler/testData/diagnostics/tests/inline/binaryExpressions/andOr.kt b/compiler/testData/diagnostics/tests/inline/binaryExpressions/andOr.kt
index d55b86e1e17..726c0f36fde 100644
--- a/compiler/testData/diagnostics/tests/inline/binaryExpressions/andOr.kt
+++ b/compiler/testData/diagnostics/tests/inline/binaryExpressions/andOr.kt
@@ -1,5 +1,5 @@
 // FIR_IDENTICAL
-// !DIAGNOSTICS: -UNUSED_EXPRESSION -UNUSED_PARAMETER -UNUSED_VARIABLE -NOTHING_TO_INLINE -ASSIGNED_BUT_NEVER_ACCESSED_VARIABLE -UNUSED_VALUE -TYPE_MISMATCH
+// !DIAGNOSTICS: -UNUSED_EXPRESSION -UNUSED_PARAMETER -UNUSED_VARIABLE -NOTHING_TO_INLINE -ASSIGNED_BUT_NEVER_ACCESSED_VARIABLE -UNUSED_VALUE -TYPE_MISMATCH -CONDITION_TYPE_MISMATCH
 
 inline fun inlineFunWithInvoke(s: (p: Int) -> Unit, ext: Int.(p: Int) -> Unit) {
     <!USAGE_IS_NOT_INLINABLE!>s<!> && <!USAGE_IS_NOT_INLINABLE!>ext<!>
diff --git a/compiler/testData/diagnostics/tests/platformTypes/nullabilityWarnings/conditions.fir.kt b/compiler/testData/diagnostics/tests/platformTypes/nullabilityWarnings/conditions.fir.kt
index 352b3c96041..d08d7080d4a 100644
--- a/compiler/testData/diagnostics/tests/platformTypes/nullabilityWarnings/conditions.fir.kt
+++ b/compiler/testData/diagnostics/tests/platformTypes/nullabilityWarnings/conditions.fir.kt
@@ -23,23 +23,23 @@ fun test() {
     val platformJ = J.staticJ
 
     if (platformNN) {}
-    if (platformN) {}
+    if (<!CONDITION_TYPE_MISMATCH!>platformN<!>) {}
     if (platformJ) {}
 
     while (platformNN) {}
-    while (platformN) {}
+    while (<!CONDITION_TYPE_MISMATCH!>platformN<!>) {}
     while (platformJ) {}
 
     do {} while (platformNN)
-    do {} while (platformN)
+    do {} while (<!CONDITION_TYPE_MISMATCH!>platformN<!>)
     do {} while (platformJ)
 
     platformNN && false
-    platformN && false
+    <!CONDITION_TYPE_MISMATCH!>platformN<!> && false
     platformJ && false
 
     platformNN || false
-    platformN || false
+    <!CONDITION_TYPE_MISMATCH!>platformN<!> || false
     platformJ || false
 
     !platformNN
diff --git a/compiler/testData/diagnostics/testsWithStdLib/contracts/smartcasts/partiallyIncorrect.fir.kt b/compiler/testData/diagnostics/testsWithStdLib/contracts/smartcasts/partiallyIncorrect.fir.kt
index b1706dd9f02..74823fcc009 100644
--- a/compiler/testData/diagnostics/testsWithStdLib/contracts/smartcasts/partiallyIncorrect.fir.kt
+++ b/compiler/testData/diagnostics/testsWithStdLib/contracts/smartcasts/partiallyIncorrect.fir.kt
@@ -12,7 +12,7 @@ fun isString(x: Any?): Boolean {
 }
 
 fun incorrectPartDoesntMatter(x: Any?) {
-    if (isString(x) && 1) {
+    if (isString(x) && <!CONDITION_TYPE_MISMATCH!>1<!>) {
         x.length
     }
     else {
diff --git a/compiler/tests-spec/testData/diagnostics/linked/expressions/conditional-expression/p-6/neg/1.1.fir.kt b/compiler/tests-spec/testData/diagnostics/linked/expressions/conditional-expression/p-6/neg/1.1.fir.kt
index 3dbfcd0cc8f..4327b3e006e 100644
--- a/compiler/tests-spec/testData/diagnostics/linked/expressions/conditional-expression/p-6/neg/1.1.fir.kt
+++ b/compiler/tests-spec/testData/diagnostics/linked/expressions/conditional-expression/p-6/neg/1.1.fir.kt
@@ -26,7 +26,7 @@ import checkSubtype
  */
 fun case1() {
     val a: Any = true
-    if (a) { "true" } else "false"
+    if (<!CONDITION_TYPE_MISMATCH!>a<!>) { "true" } else "false"
     <!NONE_APPLICABLE!>checkSubtype<!><Boolean>(a)
 }
 
@@ -37,7 +37,7 @@ fun case1() {
  */
 fun case2() {
     val a = JavaContainer.aO
-    if (a) { "true" } else "false"
+    if (<!CONDITION_TYPE_MISMATCH!>a<!>) { "true" } else "false"
     <!NONE_APPLICABLE!>checkSubtype<!><Boolean>(a)
 }
 
@@ -54,7 +54,7 @@ public class JavaClassCase3{
 fun case3() {
     val x = JavaClassCase3.id(null) // Nothing!
     <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Nothing?")!>x<!>
-    val a = if (x) {
+    val a = if (<!CONDITION_TYPE_MISMATCH!>x<!>) {
         "NOK"
     } else "NOK"
 }
diff --git a/compiler/tests-spec/testData/diagnostics/linked/expressions/logical-conjunction-expression/p-2/neg/1.1.fir.kt b/compiler/tests-spec/testData/diagnostics/linked/expressions/logical-conjunction-expression/p-2/neg/1.1.fir.kt
index e30431cfb93..f7490adf061 100644
--- a/compiler/tests-spec/testData/diagnostics/linked/expressions/logical-conjunction-expression/p-2/neg/1.1.fir.kt
+++ b/compiler/tests-spec/testData/diagnostics/linked/expressions/logical-conjunction-expression/p-2/neg/1.1.fir.kt
@@ -19,13 +19,13 @@ import checkType
 import check
 
 // TESTCASE NUMBER: 0
-fun foo() = run { false && JavaClass.VALUE && throw Exception() }
+fun foo() = run { false && <!CONDITION_TYPE_MISMATCH!>JavaClass.VALUE<!> && throw Exception() }
 
 // TESTCASE NUMBER: 1
 fun case1() {
     val a: Boolean? = false
     checkSubtype<Boolean?>(a)
-    val x4 = a && true
+    val x4 = <!CONDITION_TYPE_MISMATCH!>a<!> && true
     x4 <!OVERLOAD_RESOLUTION_AMBIGUITY!>checkType<!> { <!NONE_APPLICABLE!>check<!><Boolean>() }
 }
 
@@ -33,7 +33,7 @@ fun case1() {
 fun case2() {
     val a: Any = false
     <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Any")!>a<!>
-    val x4 = a && true
+    val x4 = <!CONDITION_TYPE_MISMATCH!>a<!> && true
     x4 <!OVERLOAD_RESOLUTION_AMBIGUITY!>checkType<!> { <!NONE_APPLICABLE!>check<!><Boolean>() }
 }
 
@@ -43,7 +43,7 @@ fun case3() {
     val a2 = JavaClass.VALUE
     <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Any..kotlin.Any?!")!>a2<!>
 
-    val x3 = a1 && a2
+    val x3 = a1 && <!CONDITION_TYPE_MISMATCH!>a2<!>
     <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Boolean")!>x3<!>
 
     x3 <!OVERLOAD_RESOLUTION_AMBIGUITY!>checkType<!> { <!NONE_APPLICABLE!>check<!><Boolean>() }
diff --git a/compiler/tests-spec/testData/diagnostics/linked/expressions/logical-disjunction-expression/p-2/neg/1.1.fir.kt b/compiler/tests-spec/testData/diagnostics/linked/expressions/logical-disjunction-expression/p-2/neg/1.1.fir.kt
index 086ec2bf430..8b119912020 100644
--- a/compiler/tests-spec/testData/diagnostics/linked/expressions/logical-disjunction-expression/p-2/neg/1.1.fir.kt
+++ b/compiler/tests-spec/testData/diagnostics/linked/expressions/logical-disjunction-expression/p-2/neg/1.1.fir.kt
@@ -19,13 +19,13 @@ import checkType
 import check
 
 // TESTCASE NUMBER: 0
-fun foo() = run { false || JavaClass.VALUE || throw Exception() }
+fun foo() = run { false || <!CONDITION_TYPE_MISMATCH!>JavaClass.VALUE<!> || throw Exception() }
 
 // TESTCASE NUMBER: 1
 fun case1() {
     val a: Boolean? = false
     checkSubtype<Boolean?>(a)
-    val x4 = a || true
+    val x4 = <!CONDITION_TYPE_MISMATCH!>a<!> || true
     x4 <!OVERLOAD_RESOLUTION_AMBIGUITY!>checkType<!> { <!NONE_APPLICABLE!>check<!><Boolean>() }
 }
 
@@ -33,7 +33,7 @@ fun case1() {
 fun case2() {
     val a: Any = false
     <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Any")!>a<!>
-    val x4 = a || true
+    val x4 = <!CONDITION_TYPE_MISMATCH!>a<!> || true
     x4 <!OVERLOAD_RESOLUTION_AMBIGUITY!>checkType<!> { <!NONE_APPLICABLE!>check<!><Boolean>() }
 }
 
@@ -43,7 +43,7 @@ fun case3() {
     val a2 = JavaClass.VALUE
     <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Any..kotlin.Any?!")!>a2<!>
 
-    val x3 = a1 || a2
+    val x3 = a1 || <!CONDITION_TYPE_MISMATCH!>a2<!>
     <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Boolean")!>x3<!>
 
     x3 <!OVERLOAD_RESOLUTION_AMBIGUITY!>checkType<!> { <!NONE_APPLICABLE!>check<!><Boolean>() }
diff --git a/compiler/tests-spec/testData/diagnostics/linked/expressions/when-expression/p-2/neg/2.1.fir.kt b/compiler/tests-spec/testData/diagnostics/linked/expressions/when-expression/p-2/neg/2.1.fir.kt
index 38c29ce9916..abf479e0504 100644
--- a/compiler/tests-spec/testData/diagnostics/linked/expressions/when-expression/p-2/neg/2.1.fir.kt
+++ b/compiler/tests-spec/testData/diagnostics/linked/expressions/when-expression/p-2/neg/2.1.fir.kt
@@ -3,12 +3,12 @@
 // TESTCASE NUMBER: 1
 fun case_1(value_1: Int, value_2: String, value_3: TypesProvider): String {
     when {
-        .012f / value_1 -> return ""
-        "$value_2..." -> return ""
-        '-' -> return ""
-        {} -> return ""
-        value_3.getAny() -> return ""
-        -10..-1 -> return ""
+        <!CONDITION_TYPE_MISMATCH!>.012f / value_1<!> -> return ""
+        <!CONDITION_TYPE_MISMATCH!>"$value_2..."<!> -> return ""
+        <!CONDITION_TYPE_MISMATCH!>'-'<!> -> return ""
+        <!CONDITION_TYPE_MISMATCH!>{}<!> -> return ""
+        <!CONDITION_TYPE_MISMATCH!>value_3.getAny()<!> -> return ""
+        <!CONDITION_TYPE_MISMATCH!>-10..-1<!> -> return ""
     }
 
     return ""
diff --git a/compiler/tests-spec/testData/diagnostics/linked/expressions/when-expression/p-2/neg/2.2.fir.kt b/compiler/tests-spec/testData/diagnostics/linked/expressions/when-expression/p-2/neg/2.2.fir.kt
index f283f98d295..b6bd26175ab 100644
--- a/compiler/tests-spec/testData/diagnostics/linked/expressions/when-expression/p-2/neg/2.2.fir.kt
+++ b/compiler/tests-spec/testData/diagnostics/linked/expressions/when-expression/p-2/neg/2.2.fir.kt
@@ -5,7 +5,7 @@ fun case_1(value_1: TypesProvider) {
     when {
         getBoolean(), value_1.getBoolean()  -> return
         value_1.getBoolean() && getBoolean(), getLong() == 1000L -> return
-        Out<Int>(), getLong(), {}, Any(), throw Exception() -> return
+        <!CONDITION_TYPE_MISMATCH!>Out<Int>()<!>, getLong(), {}, Any(), throw Exception() -> return
     }
 
     return
diff --git a/compiler/tests-spec/testData/diagnostics/linked/statements/loop-statements/do-while-loop-statement/p-3/neg/1.1.fir.kt b/compiler/tests-spec/testData/diagnostics/linked/statements/loop-statements/do-while-loop-statement/p-3/neg/1.1.fir.kt
index f6d1b161111..7796e06f34b 100644
--- a/compiler/tests-spec/testData/diagnostics/linked/statements/loop-statements/do-while-loop-statement/p-3/neg/1.1.fir.kt
+++ b/compiler/tests-spec/testData/diagnostics/linked/statements/loop-statements/do-while-loop-statement/p-3/neg/1.1.fir.kt
@@ -5,19 +5,19 @@
 // TESTCASE NUMBER: 1
 fun case1() {
     do {
-    } while ("boo")
+    } while (<!CONDITION_TYPE_MISMATCH!>"boo"<!>)
 }
 
 // TESTCASE NUMBER: 2
 fun case2() {
     val condition: Any = true
     do {
-    } while (condition)
+    } while (<!CONDITION_TYPE_MISMATCH!>condition<!>)
 }
 
 // TESTCASE NUMBER: 3
 fun case3() {
     val condition: Boolean? = true
     do {
-    } while (condition)
+    } while (<!CONDITION_TYPE_MISMATCH!>condition<!>)
 }
diff --git a/compiler/tests-spec/testData/diagnostics/linked/statements/loop-statements/while-loop-statement/p-3/neg/1.1.fir.kt b/compiler/tests-spec/testData/diagnostics/linked/statements/loop-statements/while-loop-statement/p-3/neg/1.1.fir.kt
index 8bd33023462..bf83a6f0218 100644
--- a/compiler/tests-spec/testData/diagnostics/linked/statements/loop-statements/while-loop-statement/p-3/neg/1.1.fir.kt
+++ b/compiler/tests-spec/testData/diagnostics/linked/statements/loop-statements/while-loop-statement/p-3/neg/1.1.fir.kt
@@ -6,13 +6,13 @@
 // TESTCASE NUMBER: 1
 fun case1() {
     val condition: Any = true
-    while (condition && "true") {
+    while (<!CONDITION_TYPE_MISMATCH!>condition<!> && <!CONDITION_TYPE_MISMATCH!>"true"<!>) {
     }
 }
 
 // TESTCASE NUMBER: 2
 fun case2() {
     val condition: Boolean? = true
-    while (condition) {
+    while (<!CONDITION_TYPE_MISMATCH!>condition<!>) {
     }
 }
diff --git a/compiler/tests-spec/testData/diagnostics/notLinked/dfa/pos/40.fir.kt b/compiler/tests-spec/testData/diagnostics/notLinked/dfa/pos/40.fir.kt
index 89aaeaf3d42..687fd142356 100644
--- a/compiler/tests-spec/testData/diagnostics/notLinked/dfa/pos/40.fir.kt
+++ b/compiler/tests-spec/testData/diagnostics/notLinked/dfa/pos/40.fir.kt
@@ -108,7 +108,7 @@ fun case_11(x: Any?) {
  * ISSUES: KT-30376
  */
 fun case_12(x: Any?) {
-    if (x!! as Boolean?) {
+    if (<!CONDITION_TYPE_MISMATCH!>x!! as Boolean?<!>) {
         <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Any? & kotlin.Any")!>x<!>.<!UNRESOLVED_REFERENCE!>not<!>()
         <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Any")!>select(x)<!>.<!UNRESOLVED_REFERENCE!>not<!>()
     }
diff --git a/compiler/tests-spec/testData/diagnostics/notLinked/dfa/pos/6.fir.kt b/compiler/tests-spec/testData/diagnostics/notLinked/dfa/pos/6.fir.kt
index 4d0ec43070a..8ee66a5381c 100644
--- a/compiler/tests-spec/testData/diagnostics/notLinked/dfa/pos/6.fir.kt
+++ b/compiler/tests-spec/testData/diagnostics/notLinked/dfa/pos/6.fir.kt
@@ -613,7 +613,7 @@ fun case_30(a: ((Float) -> Int?)?, b: Float?) {
 
 // TESTCASE NUMBER: 31
 fun case_31(z1: Boolean?, z: Nothing?) {
-    if (false || EnumClassWithNullableProperty.A.prop_1 != z && z1 !== z && z1) {
+    if (false || EnumClassWithNullableProperty.A.prop_1 != z && z1 !== z && <!CONDITION_TYPE_MISMATCH!>z1<!>) {
         EnumClassWithNullableProperty.A.prop_1
         EnumClassWithNullableProperty.A.prop_1<!UNSAFE_CALL!>.<!>equals(null)
         EnumClassWithNullableProperty.A.prop_1.propT