diff --git a/compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/backend/Fir2IrVisitor.kt b/compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/backend/Fir2IrVisitor.kt
index ce0f5cabdf4..67712a45e54 100644
--- a/compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/backend/Fir2IrVisitor.kt
+++ b/compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/backend/Fir2IrVisitor.kt
@@ -12,7 +12,9 @@ import org.jetbrains.kotlin.fir.declarations.impl.FirDefaultPropertyGetter
 import org.jetbrains.kotlin.fir.declarations.impl.FirDefaultPropertySetter
 import org.jetbrains.kotlin.fir.descriptors.FirModuleDescriptor
 import org.jetbrains.kotlin.fir.expressions.*
-import org.jetbrains.kotlin.fir.expressions.impl.*
+import org.jetbrains.kotlin.fir.expressions.impl.FirElseIfTrueCondition
+import org.jetbrains.kotlin.fir.expressions.impl.FirNoReceiverExpression
+import org.jetbrains.kotlin.fir.expressions.impl.FirUnitExpression
 import org.jetbrains.kotlin.fir.references.FirReference
 import org.jetbrains.kotlin.fir.references.FirResolvedNamedReference
 import org.jetbrains.kotlin.fir.references.FirSuperReference
@@ -24,6 +26,7 @@ import org.jetbrains.kotlin.fir.resolve.transformers.IntegerLiteralTypeApproxima
 import org.jetbrains.kotlin.fir.scopes.impl.FirClassSubstitutionScope
 import org.jetbrains.kotlin.fir.scopes.impl.FirIntegerOperator
 import org.jetbrains.kotlin.fir.symbols.AccessorSymbol
+import org.jetbrains.kotlin.fir.symbols.StandardClassIds
 import org.jetbrains.kotlin.fir.symbols.impl.*
 import org.jetbrains.kotlin.fir.types.*
 import org.jetbrains.kotlin.fir.visitors.FirDefaultVisitor
@@ -44,12 +47,9 @@ import org.jetbrains.kotlin.ir.symbols.*
 import org.jetbrains.kotlin.ir.types.*
 import org.jetbrains.kotlin.ir.util.*
 import org.jetbrains.kotlin.lexer.KtTokens
-import org.jetbrains.kotlin.name.ClassId
-import org.jetbrains.kotlin.name.FqName
 import org.jetbrains.kotlin.name.Name
 import org.jetbrains.kotlin.psi.*
 import org.jetbrains.kotlin.psi2ir.PsiSourceManager
-import org.jetbrains.kotlin.types.AbstractStrictEqualityTypeChecker
 import java.util.*
 
 class Fir2IrVisitor(
@@ -864,7 +864,7 @@ class Fir2IrVisitor(
         }
     }
 
-    override fun visitFunctionCall(functionCall: FirFunctionCall, data: Any?): IrElement {
+    override fun visitFunctionCall(functionCall: FirFunctionCall, data: Any?): IrExpression {
         val convertibleCall = if (functionCall.toResolvedCallableSymbol()?.fir is FirIntegerOperator) {
             functionCall.copy().transformSingle(integerApproximator, null)
         } else {
@@ -1312,50 +1312,72 @@ class Fir2IrVisitor(
         }
     }
 
-    private fun generateComparisonCall(
-        startOffset: Int, endOffset: Int, operation: FirOperation, first: FirExpression, second: FirExpression
-    ): IrExpression {
-        val firstType = first.typeRef as? FirResolvedTypeRef
-        val secondType = second.typeRef as? FirResolvedTypeRef
-        if (firstType == null || secondType == null) {
-            return IrErrorCallExpressionImpl(startOffset, endOffset, booleanType, "Comparison of arguments with unresolved types")
+    override fun visitComparisonExpression(comparisonExpression: FirComparisonExpression, data: Any?): IrElement {
+        return comparisonExpression.convertWithOffsets { startOffset, endOffset ->
+            generateComparisonCall(startOffset, endOffset, comparisonExpression)
         }
-        if (!AbstractStrictEqualityTypeChecker.strictEqualTypes(typeContext, firstType.type, secondType.type)) {
-            return IrErrorCallExpressionImpl(
-                startOffset, endOffset, booleanType,
-                "Comparison of arguments with different types: ${firstType.type.render()}, ${secondType.type.render()}"
+    }
+
+    private fun generateComparisonCall(
+        startOffset: Int, endOffset: Int,
+        comparisonExpression: FirComparisonExpression
+    ): IrExpression {
+        val operation = comparisonExpression.operation
+
+        fun fallbackToRealCall(): IrExpression {
+            val (symbol, origin) = getSymbolAndOriginForComparison(operation, irBuiltIns.intType.classifierOrFail)
+            return primitiveOp2(
+                startOffset, endOffset,
+                symbol!!,
+                booleanType,
+                origin,
+                visitFunctionCall(comparisonExpression.compareToCall, null),
+                IrConstImpl.int(startOffset, endOffset, irBuiltIns.intType, 0)
             )
         }
-        // TODO: it's temporary hack which should be refactored
-        val simpleType = when (val classId = (firstType.type as? ConeClassLikeType)?.lookupTag?.classId) {
-            ClassId(FqName("kotlin"), FqName("Long"), false) -> irBuiltIns.longType
-            ClassId(FqName("kotlin"), FqName("Int"), false) -> irBuiltIns.intType
-            ClassId(FqName("kotlin"), FqName("Float"), false) -> irBuiltIns.floatType
-            ClassId(FqName("kotlin"), FqName("Double"), false) -> irBuiltIns.doubleType
-            ClassId(FqName("kotlin"), FqName("Char"), false) -> irBuiltIns.charType
-            else -> {
-                return IrErrorCallExpressionImpl(
-                    startOffset, endOffset, booleanType, "Comparison of arguments with unsupported type: $classId"
-                )
-            }
+
+        val comparisonInfo = comparisonExpression.inferPrimitiveNumericComparisonInfo() ?: return fallbackToRealCall()
+        val comparisonType = comparisonInfo.comparisonType
+
+        // Currently inferPrimitiveNumericComparisonInfo returns null for different primitive values
+        // TODO: Support different primitive types as well and fix inferPrimitiveNumericComparisonInfo
+        require(comparisonInfo.leftPrimitiveType == comparisonInfo.rightPrimitiveType && comparisonInfo.leftType == comparisonInfo.rightType) {
+            "Contract for inferPrimitiveNumericComparisonInfo is violated"
         }
-        val classifier = simpleType.classifierOrFail
-        val (symbol, origin) = when (operation) {
+
+        val simpleType = when ((comparisonType.type as? ConeClassLikeType)?.lookupTag?.classId) {
+            StandardClassIds.Long -> irBuiltIns.longType
+            StandardClassIds.Int -> irBuiltIns.intType
+            StandardClassIds.Float -> irBuiltIns.floatType
+            StandardClassIds.Double -> irBuiltIns.doubleType
+            StandardClassIds.Char -> irBuiltIns.charType
+            else -> return fallbackToRealCall()
+        }
+
+        val (symbol, origin) = getSymbolAndOriginForComparison(operation, simpleType.classifierOrFail)
+
+        return primitiveOp2(
+            startOffset, endOffset, symbol!!, booleanType, origin,
+            comparisonExpression.left.toIrExpression(), comparisonExpression.right.toIrExpression()
+        )
+    }
+
+    private fun getSymbolAndOriginForComparison(
+        operation: FirOperation,
+        classifier: IrClassifierSymbol
+    ): Pair<IrSimpleFunctionSymbol?, IrStatementOriginImpl> {
+        return when (operation) {
             FirOperation.LT -> irBuiltIns.lessFunByOperandType[classifier] to IrStatementOrigin.LT
             FirOperation.GT -> irBuiltIns.greaterFunByOperandType[classifier] to IrStatementOrigin.GT
             FirOperation.LT_EQ -> irBuiltIns.lessOrEqualFunByOperandType[classifier] to IrStatementOrigin.LTEQ
             FirOperation.GT_EQ -> irBuiltIns.greaterOrEqualFunByOperandType[classifier] to IrStatementOrigin.GTEQ
-            else -> throw AssertionError("Unexpected comparison operation: $operation")
+            else -> error("Unexpected comparison operation: $operation")
         }
-        return primitiveOp2(startOffset, endOffset, symbol!!, booleanType, origin, first.toIrExpression(), second.toIrExpression())
     }
 
     private fun generateOperatorCall(
         startOffset: Int, endOffset: Int, operation: FirOperation, arguments: List<FirExpression>
     ): IrExpression {
-        if (operation in FirOperation.COMPARISONS) {
-            return generateComparisonCall(startOffset, endOffset, operation, arguments[0], arguments[1])
-        }
         val (type, symbol, origin) = when (operation) {
             FirOperation.EQ -> Triple(booleanType, irBuiltIns.eqeqSymbol, IrStatementOrigin.EQEQ)
             FirOperation.NOT_EQ -> Triple(booleanType, irBuiltIns.eqeqSymbol, IrStatementOrigin.EXCLEQ)
diff --git a/compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/backend/PrimitiveComparison.kt b/compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/backend/PrimitiveComparison.kt
new file mode 100644
index 00000000000..173acec1377
--- /dev/null
+++ b/compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/backend/PrimitiveComparison.kt
@@ -0,0 +1,58 @@
+/*
+ * Copyright 2010-2020 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.backend
+
+import org.jetbrains.kotlin.fir.*
+import org.jetbrains.kotlin.fir.expressions.FirComparisonExpression
+import org.jetbrains.kotlin.fir.expressions.FirExpression
+import org.jetbrains.kotlin.fir.resolve.firSymbolProvider
+import org.jetbrains.kotlin.fir.types.*
+import org.jetbrains.kotlin.utils.addToStdlib.firstNotNullResult
+
+class PrimitiveConeNumericComparisonInfo(
+    val comparisonType: ConeKotlinType,
+    val leftPrimitiveType: ConeClassLikeType,
+    val rightPrimitiveType: ConeClassLikeType,
+    val leftType: ConeKotlinType,
+    val rightType: ConeKotlinType
+)
+
+val FirComparisonExpression.left: FirExpression
+    get() = compareToCall.explicitReceiver ?: error("There should be an explicit receiver for ${compareToCall.render()}")
+
+val FirComparisonExpression.right: FirExpression
+    get() = compareToCall.arguments.getOrNull(0) ?: error("There should be a first arg for ${compareToCall.render()}")
+
+fun FirComparisonExpression.inferPrimitiveNumericComparisonInfo(): PrimitiveConeNumericComparisonInfo? {
+    val leftType = left.typeRef.coneTypeSafe<ConeKotlinType>() ?: return null
+    val rightType = right.typeRef.coneTypeSafe<ConeKotlinType>() ?: return null
+    val leftPrimitiveOrNullableType = leftType.getPrimitiveTypeOrSupertype() ?: return null
+    val rightPrimitiveOrNullableType = rightType.getPrimitiveTypeOrSupertype() ?: return null
+    val leftPrimitiveType = leftPrimitiveOrNullableType.withNullability(ConeNullability.NOT_NULL)
+    val rightPrimitiveType = rightPrimitiveOrNullableType.withNullability(ConeNullability.NOT_NULL)
+
+    // TODO: Support different types with coercion
+    if (leftPrimitiveType != rightPrimitiveType) return null
+    val leastCommonType = rightPrimitiveType
+
+    return PrimitiveConeNumericComparisonInfo(
+        leastCommonType,
+        leftPrimitiveType, rightPrimitiveType,
+        leftPrimitiveOrNullableType, rightPrimitiveOrNullableType
+    )
+}
+
+private fun ConeKotlinType.getPrimitiveTypeOrSupertype(): ConeClassLikeType? =
+    when {
+        this is ConeTypeParameterType ->
+            this.lookupTag.typeParameterSymbol.fir.bounds.firstNotNullResult {
+                it.coneTypeSafe<ConeKotlinType>()?.getPrimitiveTypeOrSupertype()
+            }
+        this is ConeClassLikeType && isPrimitiveNumberType() ->
+            this
+        else ->
+            null
+    }
diff --git a/compiler/fir/tree/src/org/jetbrains/kotlin/fir/Primitives.kt b/compiler/fir/tree/src/org/jetbrains/kotlin/fir/Primitives.kt
new file mode 100644
index 00000000000..fe25ce4033c
--- /dev/null
+++ b/compiler/fir/tree/src/org/jetbrains/kotlin/fir/Primitives.kt
@@ -0,0 +1,40 @@
+/*
+ * Copyright 2010-2020 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
+
+import org.jetbrains.kotlin.fir.symbols.StandardClassIds
+import org.jetbrains.kotlin.fir.symbols.impl.ConeClassLikeLookupTagImpl
+import org.jetbrains.kotlin.fir.types.ConeClassLikeType
+import org.jetbrains.kotlin.fir.types.impl.ConeClassLikeTypeImpl
+import org.jetbrains.kotlin.name.ClassId
+
+object PrimitiveTypes {
+    val Boolean = StandardClassIds.Boolean.createType()
+    val Char = StandardClassIds.Char.createType()
+    val Byte = StandardClassIds.Byte.createType()
+    val Short = StandardClassIds.Short.createType()
+    val Int = StandardClassIds.Int.createType()
+    val Long = StandardClassIds.Long.createType()
+    val Float = StandardClassIds.Float.createType()
+    val Double = StandardClassIds.Double.createType()
+}
+
+private fun ClassId.createType(): ConeClassLikeType = 
+    ConeClassLikeTypeImpl(ConeClassLikeLookupTagImpl(this), emptyArray(), isNullable = false)
+
+fun ConeClassLikeType.isDouble() = lookupTag.classId == StandardClassIds.Double
+fun ConeClassLikeType.isFloat() = lookupTag.classId == StandardClassIds.Float
+fun ConeClassLikeType.isLong() = lookupTag.classId == StandardClassIds.Long
+fun ConeClassLikeType.isInt() = lookupTag.classId == StandardClassIds.Int
+fun ConeClassLikeType.isShort() = lookupTag.classId == StandardClassIds.Short
+fun ConeClassLikeType.isByte() = lookupTag.classId == StandardClassIds.Byte
+
+private val PRIMITIVE_NUMBER_CLASS_IDS = setOf(
+    StandardClassIds.Double, StandardClassIds.Float, StandardClassIds.Long, StandardClassIds.Int,
+    StandardClassIds.Short, StandardClassIds.Byte
+)
+
+fun ConeClassLikeType.isPrimitiveNumberType() = lookupTag.classId in PRIMITIVE_NUMBER_CLASS_IDS
diff --git a/compiler/testData/codegen/box/binaryOp/kt11163.kt b/compiler/testData/codegen/box/binaryOp/kt11163.kt
index a2a457d017a..39ec1db35d5 100644
--- a/compiler/testData/codegen/box/binaryOp/kt11163.kt
+++ b/compiler/testData/codegen/box/binaryOp/kt11163.kt
@@ -1,4 +1,3 @@
-// IGNORE_BACKEND_FIR: JVM_IR
 operator fun Int.compareTo(c: Char) = 0
 
 fun foo(x: Int, y: Char): String {
@@ -10,4 +9,4 @@ fun foo(x: Int, y: Char): String {
 
 fun box(): String {
     return foo(42, 'O')
-}
\ No newline at end of file
+}
diff --git a/compiler/testData/codegen/box/binaryOp/kt11163_properIeee754comparisons.kt b/compiler/testData/codegen/box/binaryOp/kt11163_properIeee754comparisons.kt
index 8f11e9cf625..13829eb2e67 100644
--- a/compiler/testData/codegen/box/binaryOp/kt11163_properIeee754comparisons.kt
+++ b/compiler/testData/codegen/box/binaryOp/kt11163_properIeee754comparisons.kt
@@ -1,5 +1,4 @@
 // !LANGUAGE: +ProperIeee754Comparisons
-// IGNORE_BACKEND_FIR: JVM_IR
 operator fun Int.compareTo(c: Char) = 0
 
 fun foo(x: Int, y: Char): String {
@@ -11,4 +10,4 @@ fun foo(x: Int, y: Char): String {
 
 fun box(): String {
     return foo(42, 'O')
-}
\ No newline at end of file
+}
diff --git a/compiler/testData/codegen/box/boxingOptimization/boxedIntegersCmp.kt b/compiler/testData/codegen/box/boxingOptimization/boxedIntegersCmp.kt
index a8e0ed3d714..69fc1801c3f 100644
--- a/compiler/testData/codegen/box/boxingOptimization/boxedIntegersCmp.kt
+++ b/compiler/testData/codegen/box/boxingOptimization/boxedIntegersCmp.kt
@@ -1,4 +1,3 @@
-// IGNORE_BACKEND_FIR: JVM_IR
 inline fun ltx(a: Comparable<Any>, b: Any) = a < b
 inline fun lex(a: Comparable<Any>, b: Any) = a <= b
 inline fun gex(a: Comparable<Any>, b: Any) = a >= b
@@ -44,4 +43,4 @@ fun box(): String {
 
         else -> "OK"
     }
-}
\ No newline at end of file
+}
diff --git a/compiler/testData/codegen/box/boxingOptimization/boxedRealsCmp.kt b/compiler/testData/codegen/box/boxingOptimization/boxedRealsCmp.kt
index b22e6f46d9b..4151703f166 100644
--- a/compiler/testData/codegen/box/boxingOptimization/boxedRealsCmp.kt
+++ b/compiler/testData/codegen/box/boxingOptimization/boxedRealsCmp.kt
@@ -1,5 +1,3 @@
-// IGNORE_BACKEND_FIR: JVM_IR
-
 inline fun ltx(a: Comparable<Any>, b: Any) = a < b
 inline fun lex(a: Comparable<Any>, b: Any) = a <= b
 inline fun gex(a: Comparable<Any>, b: Any) = a >= b
@@ -79,4 +77,4 @@ fun box(): String {
 
         else -> "OK"
     }
-}
\ No newline at end of file
+}
diff --git a/compiler/testData/codegen/box/classes/kt3114.kt b/compiler/testData/codegen/box/classes/kt3114.kt
index 45731015045..f28569e1d97 100644
--- a/compiler/testData/codegen/box/classes/kt3114.kt
+++ b/compiler/testData/codegen/box/classes/kt3114.kt
@@ -1,4 +1,3 @@
-// IGNORE_BACKEND_FIR: JVM_IR
 class KeySpan(val left: String) {
 
     public fun matches(value : String) : Boolean {
@@ -11,4 +10,4 @@ class KeySpan(val left: String) {
 fun box() : String {
   KeySpan("1").matches("3")
   return "OK"
-}
\ No newline at end of file
+}
diff --git a/compiler/testData/codegen/box/functions/recursiveCompareTo.kt b/compiler/testData/codegen/box/functions/recursiveCompareTo.kt
index b96d958d0ea..564f23a6a2f 100644
--- a/compiler/testData/codegen/box/functions/recursiveCompareTo.kt
+++ b/compiler/testData/codegen/box/functions/recursiveCompareTo.kt
@@ -1,4 +1,3 @@
-// IGNORE_BACKEND_FIR: JVM_IR
 class C
 
 operator fun C.compareTo(o: C) : Int {
@@ -9,4 +8,4 @@ operator fun C.compareTo(o: C) : Int {
     return -1
 }
 
-fun box() : String = if (C() > C()) "OK" else "FAIL"
\ No newline at end of file
+fun box() : String = if (C() > C()) "OK" else "FAIL"
diff --git a/compiler/testData/codegen/box/ieee754/smartCastToDifferentTypes.kt b/compiler/testData/codegen/box/ieee754/smartCastToDifferentTypes.kt
index a700508d7a5..43d35ecd86b 100644
--- a/compiler/testData/codegen/box/ieee754/smartCastToDifferentTypes.kt
+++ b/compiler/testData/codegen/box/ieee754/smartCastToDifferentTypes.kt
@@ -1,5 +1,4 @@
 // !LANGUAGE: -ProperIeee754Comparisons
-// IGNORE_BACKEND_FIR: JVM_IR
 // IGNORE_BACKEND: NATIVE
 // DONT_TARGET_EXACT_BACKEND: JS_IR
 fun box(): String {
@@ -14,4 +13,4 @@ fun box(): String {
     }
 
     return "fail"
-}
\ No newline at end of file
+}
diff --git a/compiler/testData/codegen/box/operatorConventions/compareTo/boolean.kt b/compiler/testData/codegen/box/operatorConventions/compareTo/boolean.kt
index 135f715d24a..833e11a733a 100644
--- a/compiler/testData/codegen/box/operatorConventions/compareTo/boolean.kt
+++ b/compiler/testData/codegen/box/operatorConventions/compareTo/boolean.kt
@@ -1,4 +1,3 @@
-// IGNORE_BACKEND_FIR: JVM_IR
 fun checkLess(x: Boolean, y: Boolean) = when {
     x >= y    -> "Fail $x >= $y"
     !(x < y)  -> "Fail !($x < $y)"
diff --git a/compiler/testData/codegen/box/operatorConventions/compareTo/doubleInt.kt b/compiler/testData/codegen/box/operatorConventions/compareTo/doubleInt.kt
index cd7c43605f7..9818affbfba 100644
--- a/compiler/testData/codegen/box/operatorConventions/compareTo/doubleInt.kt
+++ b/compiler/testData/codegen/box/operatorConventions/compareTo/doubleInt.kt
@@ -1,4 +1,3 @@
-// IGNORE_BACKEND_FIR: JVM_IR
 fun checkLess(x: Double, y: Int) = when {
     x >= y    -> "Fail $x >= $y"
     !(x < y)  -> "Fail !($x < $y)"
diff --git a/compiler/testData/codegen/box/operatorConventions/compareTo/doubleLong.kt b/compiler/testData/codegen/box/operatorConventions/compareTo/doubleLong.kt
index 537833376ce..294560659ec 100644
--- a/compiler/testData/codegen/box/operatorConventions/compareTo/doubleLong.kt
+++ b/compiler/testData/codegen/box/operatorConventions/compareTo/doubleLong.kt
@@ -1,4 +1,3 @@
-// IGNORE_BACKEND_FIR: JVM_IR
 fun checkLess(x: Double, y: Long) = when {
     x >= y    -> "Fail $x >= $y"
     !(x < y)  -> "Fail !($x < $y)"
diff --git a/compiler/testData/codegen/box/operatorConventions/compareTo/extensionArray.kt b/compiler/testData/codegen/box/operatorConventions/compareTo/extensionArray.kt
index db632c2c05e..7ca0f34b787 100644
--- a/compiler/testData/codegen/box/operatorConventions/compareTo/extensionArray.kt
+++ b/compiler/testData/codegen/box/operatorConventions/compareTo/extensionArray.kt
@@ -1,4 +1,3 @@
-// IGNORE_BACKEND_FIR: JVM_IR
 fun checkLess(x: Array<Int>, y: Array<Int>) = when {
     x >= y    -> "Fail $x >= $y"
     !(x < y)  -> "Fail !($x < $y)"
diff --git a/compiler/testData/codegen/box/operatorConventions/compareTo/extensionObject.kt b/compiler/testData/codegen/box/operatorConventions/compareTo/extensionObject.kt
index 2fe17a4ca33..1f355ed16e6 100644
--- a/compiler/testData/codegen/box/operatorConventions/compareTo/extensionObject.kt
+++ b/compiler/testData/codegen/box/operatorConventions/compareTo/extensionObject.kt
@@ -1,4 +1,3 @@
-// IGNORE_BACKEND_FIR: JVM_IR
 class A(val x: Int)
 
 operator fun A.compareTo(other: A) = x.compareTo(other.x)
diff --git a/compiler/testData/codegen/box/operatorConventions/compareTo/intDouble.kt b/compiler/testData/codegen/box/operatorConventions/compareTo/intDouble.kt
index 132c63cd17d..a76709fe2db 100644
--- a/compiler/testData/codegen/box/operatorConventions/compareTo/intDouble.kt
+++ b/compiler/testData/codegen/box/operatorConventions/compareTo/intDouble.kt
@@ -1,4 +1,3 @@
-// IGNORE_BACKEND_FIR: JVM_IR
 fun checkLess(x: Int, y: Double) = when {
     x >= y    -> "Fail $x >= $y"
     !(x < y)  -> "Fail !($x < $y)"
diff --git a/compiler/testData/codegen/box/operatorConventions/compareTo/intLong.kt b/compiler/testData/codegen/box/operatorConventions/compareTo/intLong.kt
index d450971f3fb..dc91a1d0d51 100644
--- a/compiler/testData/codegen/box/operatorConventions/compareTo/intLong.kt
+++ b/compiler/testData/codegen/box/operatorConventions/compareTo/intLong.kt
@@ -1,4 +1,3 @@
-// IGNORE_BACKEND_FIR: JVM_IR
 fun checkLess(x: Int, y: Long) = when {
     x >= y    -> "Fail $x >= $y"
     !(x < y)  -> "Fail !($x < $y)"
diff --git a/compiler/testData/codegen/box/operatorConventions/compareTo/longDouble.kt b/compiler/testData/codegen/box/operatorConventions/compareTo/longDouble.kt
index 884a87d912a..90e43d49215 100644
--- a/compiler/testData/codegen/box/operatorConventions/compareTo/longDouble.kt
+++ b/compiler/testData/codegen/box/operatorConventions/compareTo/longDouble.kt
@@ -1,4 +1,3 @@
-// IGNORE_BACKEND_FIR: JVM_IR
 fun checkLess(x: Long, y: Double) = when {
     x >= y    -> "Fail $x >= $y"
     !(x < y)  -> "Fail !($x < $y)"
diff --git a/compiler/testData/codegen/box/operatorConventions/compareTo/longInt.kt b/compiler/testData/codegen/box/operatorConventions/compareTo/longInt.kt
index 38bcfbb3dd5..623a3a46e01 100644
--- a/compiler/testData/codegen/box/operatorConventions/compareTo/longInt.kt
+++ b/compiler/testData/codegen/box/operatorConventions/compareTo/longInt.kt
@@ -1,4 +1,3 @@
-// IGNORE_BACKEND_FIR: JVM_IR
 fun checkLess(x: Long, y: Int) = when {
     x >= y    -> "Fail $x >= $y"
     !(x < y)  -> "Fail !($x < $y)"
diff --git a/compiler/testData/codegen/box/primitiveTypes/kt3078.kt b/compiler/testData/codegen/box/primitiveTypes/kt3078.kt
index 61a5e671193..cd834c89b2f 100644
--- a/compiler/testData/codegen/box/primitiveTypes/kt3078.kt
+++ b/compiler/testData/codegen/box/primitiveTypes/kt3078.kt
@@ -1,5 +1,3 @@
-// IGNORE_BACKEND_FIR: JVM_IR
-
 fun box(): String {
     if (1 >= 1.9) return "Fail #1"
     if (1.compareTo(1.1) >= 0) return "Fail #2"
diff --git a/compiler/testData/ir/irText/expressions/conventionComparisons.fir.txt b/compiler/testData/ir/irText/expressions/conventionComparisons.fir.txt
index b9c33f1c83a..ccdce811ae6 100644
--- a/compiler/testData/ir/irText/expressions/conventionComparisons.fir.txt
+++ b/compiler/testData/ir/irText/expressions/conventionComparisons.fir.txt
@@ -39,25 +39,45 @@ FILE fqName:<root> fileName:/conventionComparisons.kt
     VALUE_PARAMETER name:a2 index:1 type:<root>.IA
     BLOCK_BODY
       RETURN type=kotlin.Nothing from='public final fun test1 (a1: <root>.IA, a2: <root>.IA): kotlin.Boolean declared in <root>'
-        ERROR_CALL 'Comparison of arguments with unsupported type: /IA' type=kotlin.Boolean
+        CALL 'public final fun greater (arg0: kotlin.Int, arg1: kotlin.Int): kotlin.Boolean declared in kotlin.internal.ir' type=kotlin.Boolean origin=GT
+          arg0: CALL 'public abstract fun compareTo (other: <root>.IA): kotlin.Int [operator] declared in <root>.IB' type=kotlin.Int origin=null
+            $this: GET_VAR '<this>: <root>.IB declared in <root>.test1' type=<root>.IB origin=null
+            $receiver: GET_VAR 'a1: <root>.IA declared in <root>.test1' type=<root>.IA origin=null
+            other: GET_VAR 'a2: <root>.IA declared in <root>.test1' type=<root>.IA origin=null
+          arg1: CONST Int type=kotlin.Int value=0
   FUN name:test2 visibility:public modality:FINAL <> ($receiver:<root>.IB, a1:<root>.IA, a2:<root>.IA) returnType:kotlin.Boolean
     $receiver: VALUE_PARAMETER name:<this> type:<root>.IB
     VALUE_PARAMETER name:a1 index:0 type:<root>.IA
     VALUE_PARAMETER name:a2 index:1 type:<root>.IA
     BLOCK_BODY
       RETURN type=kotlin.Nothing from='public final fun test2 (a1: <root>.IA, a2: <root>.IA): kotlin.Boolean declared in <root>'
-        ERROR_CALL 'Comparison of arguments with unsupported type: /IA' type=kotlin.Boolean
+        CALL 'public final fun greaterOrEqual (arg0: kotlin.Int, arg1: kotlin.Int): kotlin.Boolean declared in kotlin.internal.ir' type=kotlin.Boolean origin=GTEQ
+          arg0: CALL 'public abstract fun compareTo (other: <root>.IA): kotlin.Int [operator] declared in <root>.IB' type=kotlin.Int origin=null
+            $this: GET_VAR '<this>: <root>.IB declared in <root>.test2' type=<root>.IB origin=null
+            $receiver: GET_VAR 'a1: <root>.IA declared in <root>.test2' type=<root>.IA origin=null
+            other: GET_VAR 'a2: <root>.IA declared in <root>.test2' type=<root>.IA origin=null
+          arg1: CONST Int type=kotlin.Int value=0
   FUN name:test3 visibility:public modality:FINAL <> ($receiver:<root>.IB, a1:<root>.IA, a2:<root>.IA) returnType:kotlin.Boolean
     $receiver: VALUE_PARAMETER name:<this> type:<root>.IB
     VALUE_PARAMETER name:a1 index:0 type:<root>.IA
     VALUE_PARAMETER name:a2 index:1 type:<root>.IA
     BLOCK_BODY
       RETURN type=kotlin.Nothing from='public final fun test3 (a1: <root>.IA, a2: <root>.IA): kotlin.Boolean declared in <root>'
-        ERROR_CALL 'Comparison of arguments with unsupported type: /IA' type=kotlin.Boolean
+        CALL 'public final fun less (arg0: kotlin.Int, arg1: kotlin.Int): kotlin.Boolean declared in kotlin.internal.ir' type=kotlin.Boolean origin=LT
+          arg0: CALL 'public abstract fun compareTo (other: <root>.IA): kotlin.Int [operator] declared in <root>.IB' type=kotlin.Int origin=null
+            $this: GET_VAR '<this>: <root>.IB declared in <root>.test3' type=<root>.IB origin=null
+            $receiver: GET_VAR 'a1: <root>.IA declared in <root>.test3' type=<root>.IA origin=null
+            other: GET_VAR 'a2: <root>.IA declared in <root>.test3' type=<root>.IA origin=null
+          arg1: CONST Int type=kotlin.Int value=0
   FUN name:test4 visibility:public modality:FINAL <> ($receiver:<root>.IB, a1:<root>.IA, a2:<root>.IA) returnType:kotlin.Boolean
     $receiver: VALUE_PARAMETER name:<this> type:<root>.IB
     VALUE_PARAMETER name:a1 index:0 type:<root>.IA
     VALUE_PARAMETER name:a2 index:1 type:<root>.IA
     BLOCK_BODY
       RETURN type=kotlin.Nothing from='public final fun test4 (a1: <root>.IA, a2: <root>.IA): kotlin.Boolean declared in <root>'
-        ERROR_CALL 'Comparison of arguments with unsupported type: /IA' type=kotlin.Boolean
+        CALL 'public final fun lessOrEqual (arg0: kotlin.Int, arg1: kotlin.Int): kotlin.Boolean declared in kotlin.internal.ir' type=kotlin.Boolean origin=LTEQ
+          arg0: CALL 'public abstract fun compareTo (other: <root>.IA): kotlin.Int [operator] declared in <root>.IB' type=kotlin.Int origin=null
+            $this: GET_VAR '<this>: <root>.IB declared in <root>.test4' type=<root>.IB origin=null
+            $receiver: GET_VAR 'a1: <root>.IA declared in <root>.test4' type=<root>.IA origin=null
+            other: GET_VAR 'a2: <root>.IA declared in <root>.test4' type=<root>.IA origin=null
+          arg1: CONST Int type=kotlin.Int value=0
diff --git a/compiler/testData/ir/irText/expressions/floatingPointComparisons/floatingPointLess.fir.txt b/compiler/testData/ir/irText/expressions/floatingPointComparisons/floatingPointLess.fir.txt
index 416426b4cb4..95a5c8de757 100644
--- a/compiler/testData/ir/irText/expressions/floatingPointComparisons/floatingPointLess.fir.txt
+++ b/compiler/testData/ir/irText/expressions/floatingPointComparisons/floatingPointLess.fir.txt
@@ -111,7 +111,13 @@ FILE fqName:<root> fileName:/floatingPointLess.kt
               BRANCH
                 if: CONST Boolean type=kotlin.Boolean value=true
                 then: CONST Boolean type=kotlin.Boolean value=false
-            then: ERROR_CALL 'Comparison of arguments with different types: kotlin/Float, kotlin/Double' type=kotlin.Boolean
+            then: CALL 'public final fun less (arg0: kotlin.Int, arg1: kotlin.Int): kotlin.Boolean declared in kotlin.internal.ir' type=kotlin.Boolean origin=LT
+              arg0: CALL 'public final fun compareTo (other: kotlin.Double): kotlin.Int [operator] declared in kotlin.Float' type=kotlin.Int origin=null
+                $this: TYPE_OP type=kotlin.Float origin=IMPLICIT_CAST typeOperand=kotlin.Float
+                  GET_VAR 'x: kotlin.Any declared in <root>.testFD' type=kotlin.Any origin=null
+                other: TYPE_OP type=kotlin.Double origin=IMPLICIT_CAST typeOperand=kotlin.Double
+                  GET_VAR 'y: kotlin.Any declared in <root>.testFD' type=kotlin.Any origin=null
+              arg1: CONST Int type=kotlin.Int value=0
           BRANCH
             if: CONST Boolean type=kotlin.Boolean value=true
             then: CONST Boolean type=kotlin.Boolean value=false
@@ -131,7 +137,13 @@ FILE fqName:<root> fileName:/floatingPointLess.kt
               BRANCH
                 if: CONST Boolean type=kotlin.Boolean value=true
                 then: CONST Boolean type=kotlin.Boolean value=false
-            then: ERROR_CALL 'Comparison of arguments with different types: kotlin/Double, kotlin/Float' type=kotlin.Boolean
+            then: CALL 'public final fun less (arg0: kotlin.Int, arg1: kotlin.Int): kotlin.Boolean declared in kotlin.internal.ir' type=kotlin.Boolean origin=LT
+              arg0: CALL 'public final fun compareTo (other: kotlin.Float): kotlin.Int [operator] declared in kotlin.Double' type=kotlin.Int origin=null
+                $this: TYPE_OP type=kotlin.Double origin=IMPLICIT_CAST typeOperand=kotlin.Double
+                  GET_VAR 'x: kotlin.Any declared in <root>.testDF' type=kotlin.Any origin=null
+                other: TYPE_OP type=kotlin.Float origin=IMPLICIT_CAST typeOperand=kotlin.Float
+                  GET_VAR 'y: kotlin.Any declared in <root>.testDF' type=kotlin.Any origin=null
+              arg1: CONST Int type=kotlin.Int value=0
           BRANCH
             if: CONST Boolean type=kotlin.Boolean value=true
             then: CONST Boolean type=kotlin.Boolean value=false
diff --git a/compiler/testData/ir/irText/expressions/floatingPointComparisons/nullableAnyAsIntToDouble.fir.txt b/compiler/testData/ir/irText/expressions/floatingPointComparisons/nullableAnyAsIntToDouble.fir.txt
index fafc14f76f5..6feca7245cc 100644
--- a/compiler/testData/ir/irText/expressions/floatingPointComparisons/nullableAnyAsIntToDouble.fir.txt
+++ b/compiler/testData/ir/irText/expressions/floatingPointComparisons/nullableAnyAsIntToDouble.fir.txt
@@ -8,7 +8,12 @@ FILE fqName:<root> fileName:/nullableAnyAsIntToDouble.kt
           BRANCH
             if: TYPE_OP type=kotlin.Boolean origin=INSTANCEOF typeOperand=kotlin.Int
               GET_VAR 'x: kotlin.Any? declared in <root>.test' type=kotlin.Any? origin=null
-            then: ERROR_CALL 'Comparison of arguments with different types: kotlin/Int, kotlin/Double' type=kotlin.Boolean
+            then: CALL 'public final fun less (arg0: kotlin.Int, arg1: kotlin.Int): kotlin.Boolean declared in kotlin.internal.ir' type=kotlin.Boolean origin=LT
+              arg0: CALL 'public final fun compareTo (other: kotlin.Double): kotlin.Int [operator] declared in kotlin.Int' type=kotlin.Int origin=null
+                $this: TYPE_OP type=kotlin.Int origin=IMPLICIT_CAST typeOperand=kotlin.Int
+                  GET_VAR 'x: kotlin.Any? declared in <root>.test' type=kotlin.Any? origin=null
+                other: GET_VAR 'y: kotlin.Double declared in <root>.test' type=kotlin.Double origin=null
+              arg1: CONST Int type=kotlin.Int value=0
           BRANCH
             if: CONST Boolean type=kotlin.Boolean value=true
             then: CONST Boolean type=kotlin.Boolean value=false
diff --git a/compiler/testData/ir/irText/expressions/kt23030.fir.txt b/compiler/testData/ir/irText/expressions/kt23030.fir.txt
index 54d6b4cfd37..084ef716e93 100644
--- a/compiler/testData/ir/irText/expressions/kt23030.fir.txt
+++ b/compiler/testData/ir/irText/expressions/kt23030.fir.txt
@@ -10,7 +10,11 @@ FILE fqName:<root> fileName:/kt23030.kt
     VALUE_PARAMETER name:y index:1 type:kotlin.Char
     BLOCK_BODY
       RETURN type=kotlin.Nothing from='public final fun testOverloadedCompareToCall (x: kotlin.Int, y: kotlin.Char): kotlin.Boolean declared in <root>'
-        ERROR_CALL 'Comparison of arguments with different types: kotlin/Int, kotlin/Char' type=kotlin.Boolean
+        CALL 'public final fun less (arg0: kotlin.Int, arg1: kotlin.Int): kotlin.Boolean declared in kotlin.internal.ir' type=kotlin.Boolean origin=LT
+          arg0: CALL 'public final fun compareTo (c: kotlin.Char): kotlin.Int [operator] declared in <root>' type=kotlin.Int origin=null
+            $receiver: GET_VAR 'x: kotlin.Int declared in <root>.testOverloadedCompareToCall' type=kotlin.Int origin=null
+            c: GET_VAR 'y: kotlin.Char declared in <root>.testOverloadedCompareToCall' type=kotlin.Char origin=null
+          arg1: CONST Int type=kotlin.Int value=0
   FUN name:testOverloadedCompareToCallWithSmartCast visibility:public modality:FINAL <> (x:kotlin.Any, y:kotlin.Any) returnType:kotlin.Boolean
     VALUE_PARAMETER name:x index:0 type:kotlin.Any
     VALUE_PARAMETER name:y index:1 type:kotlin.Any
@@ -27,7 +31,13 @@ FILE fqName:<root> fileName:/kt23030.kt
               BRANCH
                 if: CONST Boolean type=kotlin.Boolean value=true
                 then: CONST Boolean type=kotlin.Boolean value=false
-            then: ERROR_CALL 'Comparison of arguments with different types: kotlin/Int, kotlin/Char' type=kotlin.Boolean
+            then: CALL 'public final fun less (arg0: kotlin.Int, arg1: kotlin.Int): kotlin.Boolean declared in kotlin.internal.ir' type=kotlin.Boolean origin=LT
+              arg0: CALL 'public final fun compareTo (c: kotlin.Char): kotlin.Int [operator] declared in <root>' type=kotlin.Int origin=null
+                $receiver: TYPE_OP type=kotlin.Int origin=IMPLICIT_CAST typeOperand=kotlin.Int
+                  GET_VAR 'x: kotlin.Any declared in <root>.testOverloadedCompareToCallWithSmartCast' type=kotlin.Any origin=null
+                c: TYPE_OP type=kotlin.Char origin=IMPLICIT_CAST typeOperand=kotlin.Char
+                  GET_VAR 'y: kotlin.Any declared in <root>.testOverloadedCompareToCallWithSmartCast' type=kotlin.Any origin=null
+              arg1: CONST Int type=kotlin.Int value=0
           BRANCH
             if: CONST Boolean type=kotlin.Boolean value=true
             then: CONST Boolean type=kotlin.Boolean value=false
@@ -74,7 +84,12 @@ FILE fqName:<root> fileName:/kt23030.kt
       VALUE_PARAMETER name:y index:1 type:kotlin.Char
       BLOCK_BODY
         RETURN type=kotlin.Nothing from='public final fun testMemberExtensionCompareToCall (x: kotlin.Int, y: kotlin.Char): kotlin.Boolean declared in <root>.C'
-          ERROR_CALL 'Comparison of arguments with different types: kotlin/Int, kotlin/Char' type=kotlin.Boolean
+          CALL 'public final fun less (arg0: kotlin.Int, arg1: kotlin.Int): kotlin.Boolean declared in kotlin.internal.ir' type=kotlin.Boolean origin=LT
+            arg0: CALL 'public final fun compareTo (c: kotlin.Char): kotlin.Int [operator] declared in <root>.C' type=kotlin.Int origin=null
+              $this: GET_VAR '<this>: <root>.C declared in <root>.C.testMemberExtensionCompareToCall' type=<root>.C origin=null
+              $receiver: GET_VAR 'x: kotlin.Int declared in <root>.C.testMemberExtensionCompareToCall' type=kotlin.Int origin=null
+              c: GET_VAR 'y: kotlin.Char declared in <root>.C.testMemberExtensionCompareToCall' type=kotlin.Char origin=null
+            arg1: CONST Int type=kotlin.Int value=0
     FUN name:testMemberExtensionCompareToCallWithSmartCast visibility:public modality:FINAL <> ($this:<root>.C, x:kotlin.Any, y:kotlin.Any) returnType:kotlin.Boolean
       $this: VALUE_PARAMETER name:<this> type:<root>.C
       VALUE_PARAMETER name:x index:0 type:kotlin.Any
@@ -92,7 +107,14 @@ FILE fqName:<root> fileName:/kt23030.kt
                 BRANCH
                   if: CONST Boolean type=kotlin.Boolean value=true
                   then: CONST Boolean type=kotlin.Boolean value=false
-              then: ERROR_CALL 'Comparison of arguments with different types: kotlin/Int, kotlin/Char' type=kotlin.Boolean
+              then: CALL 'public final fun less (arg0: kotlin.Int, arg1: kotlin.Int): kotlin.Boolean declared in kotlin.internal.ir' type=kotlin.Boolean origin=LT
+                arg0: CALL 'public final fun compareTo (c: kotlin.Char): kotlin.Int [operator] declared in <root>.C' type=kotlin.Int origin=null
+                  $this: GET_VAR '<this>: <root>.C declared in <root>.C.testMemberExtensionCompareToCallWithSmartCast' type=<root>.C origin=null
+                  $receiver: TYPE_OP type=kotlin.Int origin=IMPLICIT_CAST typeOperand=kotlin.Int
+                    GET_VAR 'x: kotlin.Any declared in <root>.C.testMemberExtensionCompareToCallWithSmartCast' type=kotlin.Any origin=null
+                  c: TYPE_OP type=kotlin.Char origin=IMPLICIT_CAST typeOperand=kotlin.Char
+                    GET_VAR 'y: kotlin.Any declared in <root>.C.testMemberExtensionCompareToCallWithSmartCast' type=kotlin.Any origin=null
+                arg1: CONST Int type=kotlin.Int value=0
             BRANCH
               if: CONST Boolean type=kotlin.Boolean value=true
               then: CONST Boolean type=kotlin.Boolean value=false
diff --git a/compiler/testData/ir/irText/expressions/primitiveComparisons.fir.txt b/compiler/testData/ir/irText/expressions/primitiveComparisons.fir.txt
index e4cd920d1c8..4b3b441d206 100644
--- a/compiler/testData/ir/irText/expressions/primitiveComparisons.fir.txt
+++ b/compiler/testData/ir/irText/expressions/primitiveComparisons.fir.txt
@@ -4,49 +4,81 @@ FILE fqName:<root> fileName:/primitiveComparisons.kt
     VALUE_PARAMETER name:b index:1 type:kotlin.Byte
     BLOCK_BODY
       RETURN type=kotlin.Nothing from='public final fun btest1 (a: kotlin.Byte, b: kotlin.Byte): kotlin.Boolean declared in <root>'
-        ERROR_CALL 'Comparison of arguments with unsupported type: kotlin/Byte' type=kotlin.Boolean
+        CALL 'public final fun greater (arg0: kotlin.Int, arg1: kotlin.Int): kotlin.Boolean declared in kotlin.internal.ir' type=kotlin.Boolean origin=GT
+          arg0: CALL 'public open fun compareTo (other: kotlin.Byte): kotlin.Int [operator] declared in kotlin.Byte' type=kotlin.Int origin=null
+            $this: GET_VAR 'a: kotlin.Byte declared in <root>.btest1' type=kotlin.Byte origin=null
+            other: GET_VAR 'b: kotlin.Byte declared in <root>.btest1' type=kotlin.Byte origin=null
+          arg1: CONST Int type=kotlin.Int value=0
   FUN name:btest2 visibility:public modality:FINAL <> (a:kotlin.Byte, b:kotlin.Byte) returnType:kotlin.Boolean
     VALUE_PARAMETER name:a index:0 type:kotlin.Byte
     VALUE_PARAMETER name:b index:1 type:kotlin.Byte
     BLOCK_BODY
       RETURN type=kotlin.Nothing from='public final fun btest2 (a: kotlin.Byte, b: kotlin.Byte): kotlin.Boolean declared in <root>'
-        ERROR_CALL 'Comparison of arguments with unsupported type: kotlin/Byte' type=kotlin.Boolean
+        CALL 'public final fun less (arg0: kotlin.Int, arg1: kotlin.Int): kotlin.Boolean declared in kotlin.internal.ir' type=kotlin.Boolean origin=LT
+          arg0: CALL 'public open fun compareTo (other: kotlin.Byte): kotlin.Int [operator] declared in kotlin.Byte' type=kotlin.Int origin=null
+            $this: GET_VAR 'a: kotlin.Byte declared in <root>.btest2' type=kotlin.Byte origin=null
+            other: GET_VAR 'b: kotlin.Byte declared in <root>.btest2' type=kotlin.Byte origin=null
+          arg1: CONST Int type=kotlin.Int value=0
   FUN name:btest3 visibility:public modality:FINAL <> (a:kotlin.Byte, b:kotlin.Byte) returnType:kotlin.Boolean
     VALUE_PARAMETER name:a index:0 type:kotlin.Byte
     VALUE_PARAMETER name:b index:1 type:kotlin.Byte
     BLOCK_BODY
       RETURN type=kotlin.Nothing from='public final fun btest3 (a: kotlin.Byte, b: kotlin.Byte): kotlin.Boolean declared in <root>'
-        ERROR_CALL 'Comparison of arguments with unsupported type: kotlin/Byte' type=kotlin.Boolean
+        CALL 'public final fun greaterOrEqual (arg0: kotlin.Int, arg1: kotlin.Int): kotlin.Boolean declared in kotlin.internal.ir' type=kotlin.Boolean origin=GTEQ
+          arg0: CALL 'public open fun compareTo (other: kotlin.Byte): kotlin.Int [operator] declared in kotlin.Byte' type=kotlin.Int origin=null
+            $this: GET_VAR 'a: kotlin.Byte declared in <root>.btest3' type=kotlin.Byte origin=null
+            other: GET_VAR 'b: kotlin.Byte declared in <root>.btest3' type=kotlin.Byte origin=null
+          arg1: CONST Int type=kotlin.Int value=0
   FUN name:btest4 visibility:public modality:FINAL <> (a:kotlin.Byte, b:kotlin.Byte) returnType:kotlin.Boolean
     VALUE_PARAMETER name:a index:0 type:kotlin.Byte
     VALUE_PARAMETER name:b index:1 type:kotlin.Byte
     BLOCK_BODY
       RETURN type=kotlin.Nothing from='public final fun btest4 (a: kotlin.Byte, b: kotlin.Byte): kotlin.Boolean declared in <root>'
-        ERROR_CALL 'Comparison of arguments with unsupported type: kotlin/Byte' type=kotlin.Boolean
+        CALL 'public final fun lessOrEqual (arg0: kotlin.Int, arg1: kotlin.Int): kotlin.Boolean declared in kotlin.internal.ir' type=kotlin.Boolean origin=LTEQ
+          arg0: CALL 'public open fun compareTo (other: kotlin.Byte): kotlin.Int [operator] declared in kotlin.Byte' type=kotlin.Int origin=null
+            $this: GET_VAR 'a: kotlin.Byte declared in <root>.btest4' type=kotlin.Byte origin=null
+            other: GET_VAR 'b: kotlin.Byte declared in <root>.btest4' type=kotlin.Byte origin=null
+          arg1: CONST Int type=kotlin.Int value=0
   FUN name:stest1 visibility:public modality:FINAL <> (a:kotlin.Short, b:kotlin.Short) returnType:kotlin.Boolean
     VALUE_PARAMETER name:a index:0 type:kotlin.Short
     VALUE_PARAMETER name:b index:1 type:kotlin.Short
     BLOCK_BODY
       RETURN type=kotlin.Nothing from='public final fun stest1 (a: kotlin.Short, b: kotlin.Short): kotlin.Boolean declared in <root>'
-        ERROR_CALL 'Comparison of arguments with unsupported type: kotlin/Short' type=kotlin.Boolean
+        CALL 'public final fun greater (arg0: kotlin.Int, arg1: kotlin.Int): kotlin.Boolean declared in kotlin.internal.ir' type=kotlin.Boolean origin=GT
+          arg0: CALL 'public open fun compareTo (other: kotlin.Short): kotlin.Int [operator] declared in kotlin.Short' type=kotlin.Int origin=null
+            $this: GET_VAR 'a: kotlin.Short declared in <root>.stest1' type=kotlin.Short origin=null
+            other: GET_VAR 'b: kotlin.Short declared in <root>.stest1' type=kotlin.Short origin=null
+          arg1: CONST Int type=kotlin.Int value=0
   FUN name:stest2 visibility:public modality:FINAL <> (a:kotlin.Short, b:kotlin.Short) returnType:kotlin.Boolean
     VALUE_PARAMETER name:a index:0 type:kotlin.Short
     VALUE_PARAMETER name:b index:1 type:kotlin.Short
     BLOCK_BODY
       RETURN type=kotlin.Nothing from='public final fun stest2 (a: kotlin.Short, b: kotlin.Short): kotlin.Boolean declared in <root>'
-        ERROR_CALL 'Comparison of arguments with unsupported type: kotlin/Short' type=kotlin.Boolean
+        CALL 'public final fun less (arg0: kotlin.Int, arg1: kotlin.Int): kotlin.Boolean declared in kotlin.internal.ir' type=kotlin.Boolean origin=LT
+          arg0: CALL 'public open fun compareTo (other: kotlin.Short): kotlin.Int [operator] declared in kotlin.Short' type=kotlin.Int origin=null
+            $this: GET_VAR 'a: kotlin.Short declared in <root>.stest2' type=kotlin.Short origin=null
+            other: GET_VAR 'b: kotlin.Short declared in <root>.stest2' type=kotlin.Short origin=null
+          arg1: CONST Int type=kotlin.Int value=0
   FUN name:stest3 visibility:public modality:FINAL <> (a:kotlin.Short, b:kotlin.Short) returnType:kotlin.Boolean
     VALUE_PARAMETER name:a index:0 type:kotlin.Short
     VALUE_PARAMETER name:b index:1 type:kotlin.Short
     BLOCK_BODY
       RETURN type=kotlin.Nothing from='public final fun stest3 (a: kotlin.Short, b: kotlin.Short): kotlin.Boolean declared in <root>'
-        ERROR_CALL 'Comparison of arguments with unsupported type: kotlin/Short' type=kotlin.Boolean
+        CALL 'public final fun greaterOrEqual (arg0: kotlin.Int, arg1: kotlin.Int): kotlin.Boolean declared in kotlin.internal.ir' type=kotlin.Boolean origin=GTEQ
+          arg0: CALL 'public open fun compareTo (other: kotlin.Short): kotlin.Int [operator] declared in kotlin.Short' type=kotlin.Int origin=null
+            $this: GET_VAR 'a: kotlin.Short declared in <root>.stest3' type=kotlin.Short origin=null
+            other: GET_VAR 'b: kotlin.Short declared in <root>.stest3' type=kotlin.Short origin=null
+          arg1: CONST Int type=kotlin.Int value=0
   FUN name:stest4 visibility:public modality:FINAL <> (a:kotlin.Short, b:kotlin.Short) returnType:kotlin.Boolean
     VALUE_PARAMETER name:a index:0 type:kotlin.Short
     VALUE_PARAMETER name:b index:1 type:kotlin.Short
     BLOCK_BODY
       RETURN type=kotlin.Nothing from='public final fun stest4 (a: kotlin.Short, b: kotlin.Short): kotlin.Boolean declared in <root>'
-        ERROR_CALL 'Comparison of arguments with unsupported type: kotlin/Short' type=kotlin.Boolean
+        CALL 'public final fun lessOrEqual (arg0: kotlin.Int, arg1: kotlin.Int): kotlin.Boolean declared in kotlin.internal.ir' type=kotlin.Boolean origin=LTEQ
+          arg0: CALL 'public open fun compareTo (other: kotlin.Short): kotlin.Int [operator] declared in kotlin.Short' type=kotlin.Int origin=null
+            $this: GET_VAR 'a: kotlin.Short declared in <root>.stest4' type=kotlin.Short origin=null
+            other: GET_VAR 'b: kotlin.Short declared in <root>.stest4' type=kotlin.Short origin=null
+          arg1: CONST Int type=kotlin.Int value=0
   FUN name:itest1 visibility:public modality:FINAL <> (a:kotlin.Int, b:kotlin.Int) returnType:kotlin.Boolean
     VALUE_PARAMETER name:a index:0 type:kotlin.Int
     VALUE_PARAMETER name:b index:1 type:kotlin.Int
diff --git a/compiler/testData/ir/irText/expressions/stringComparisons.fir.txt b/compiler/testData/ir/irText/expressions/stringComparisons.fir.txt
index c2b5f66e84b..f09a8ea67a9 100644
--- a/compiler/testData/ir/irText/expressions/stringComparisons.fir.txt
+++ b/compiler/testData/ir/irText/expressions/stringComparisons.fir.txt
@@ -4,22 +4,38 @@ FILE fqName:<root> fileName:/stringComparisons.kt
     VALUE_PARAMETER name:b index:1 type:kotlin.String
     BLOCK_BODY
       RETURN type=kotlin.Nothing from='public final fun test1 (a: kotlin.String, b: kotlin.String): kotlin.Boolean declared in <root>'
-        ERROR_CALL 'Comparison of arguments with unsupported type: kotlin/String' type=kotlin.Boolean
+        CALL 'public final fun greater (arg0: kotlin.Int, arg1: kotlin.Int): kotlin.Boolean declared in kotlin.internal.ir' type=kotlin.Boolean origin=GT
+          arg0: CALL 'public open fun compareTo (other: kotlin.String): kotlin.Int [operator] declared in kotlin.String' type=kotlin.Int origin=null
+            $this: GET_VAR 'a: kotlin.String declared in <root>.test1' type=kotlin.String origin=null
+            other: GET_VAR 'b: kotlin.String declared in <root>.test1' type=kotlin.String origin=null
+          arg1: CONST Int type=kotlin.Int value=0
   FUN name:test2 visibility:public modality:FINAL <> (a:kotlin.String, b:kotlin.String) returnType:kotlin.Boolean
     VALUE_PARAMETER name:a index:0 type:kotlin.String
     VALUE_PARAMETER name:b index:1 type:kotlin.String
     BLOCK_BODY
       RETURN type=kotlin.Nothing from='public final fun test2 (a: kotlin.String, b: kotlin.String): kotlin.Boolean declared in <root>'
-        ERROR_CALL 'Comparison of arguments with unsupported type: kotlin/String' type=kotlin.Boolean
+        CALL 'public final fun less (arg0: kotlin.Int, arg1: kotlin.Int): kotlin.Boolean declared in kotlin.internal.ir' type=kotlin.Boolean origin=LT
+          arg0: CALL 'public open fun compareTo (other: kotlin.String): kotlin.Int [operator] declared in kotlin.String' type=kotlin.Int origin=null
+            $this: GET_VAR 'a: kotlin.String declared in <root>.test2' type=kotlin.String origin=null
+            other: GET_VAR 'b: kotlin.String declared in <root>.test2' type=kotlin.String origin=null
+          arg1: CONST Int type=kotlin.Int value=0
   FUN name:test3 visibility:public modality:FINAL <> (a:kotlin.String, b:kotlin.String) returnType:kotlin.Boolean
     VALUE_PARAMETER name:a index:0 type:kotlin.String
     VALUE_PARAMETER name:b index:1 type:kotlin.String
     BLOCK_BODY
       RETURN type=kotlin.Nothing from='public final fun test3 (a: kotlin.String, b: kotlin.String): kotlin.Boolean declared in <root>'
-        ERROR_CALL 'Comparison of arguments with unsupported type: kotlin/String' type=kotlin.Boolean
+        CALL 'public final fun greaterOrEqual (arg0: kotlin.Int, arg1: kotlin.Int): kotlin.Boolean declared in kotlin.internal.ir' type=kotlin.Boolean origin=GTEQ
+          arg0: CALL 'public open fun compareTo (other: kotlin.String): kotlin.Int [operator] declared in kotlin.String' type=kotlin.Int origin=null
+            $this: GET_VAR 'a: kotlin.String declared in <root>.test3' type=kotlin.String origin=null
+            other: GET_VAR 'b: kotlin.String declared in <root>.test3' type=kotlin.String origin=null
+          arg1: CONST Int type=kotlin.Int value=0
   FUN name:test4 visibility:public modality:FINAL <> (a:kotlin.String, b:kotlin.String) returnType:kotlin.Boolean
     VALUE_PARAMETER name:a index:0 type:kotlin.String
     VALUE_PARAMETER name:b index:1 type:kotlin.String
     BLOCK_BODY
       RETURN type=kotlin.Nothing from='public final fun test4 (a: kotlin.String, b: kotlin.String): kotlin.Boolean declared in <root>'
-        ERROR_CALL 'Comparison of arguments with unsupported type: kotlin/String' type=kotlin.Boolean
+        CALL 'public final fun lessOrEqual (arg0: kotlin.Int, arg1: kotlin.Int): kotlin.Boolean declared in kotlin.internal.ir' type=kotlin.Boolean origin=LTEQ
+          arg0: CALL 'public open fun compareTo (other: kotlin.String): kotlin.Int [operator] declared in kotlin.String' type=kotlin.Int origin=null
+            $this: GET_VAR 'a: kotlin.String declared in <root>.test4' type=kotlin.String origin=null
+            other: GET_VAR 'b: kotlin.String declared in <root>.test4' type=kotlin.String origin=null
+          arg1: CONST Int type=kotlin.Int value=0