JVM IR: Avoid direct invokes in callable reference tests

Due to the direct invoke optimization, most callable reference tests
were not generating callable references/lambdas.

compiler/testData/codegen/box/callableReference/bound/arrayGetIntrinsic.kt

@@ -1,4 +1,4 @@
 
 fun box(): String {
-    return if ((arrayOf(1, 2, 3)::get)(1) == 2) "OK" else "Fail"
+    return if ((arrayOf(1, 2, 3)::get).let { it(1) } == 2) "OK" else "Fail"
 }

compiler/testData/codegen/box/callableReference/bound/companionObjectReceiver.kt

@@ -5,4 +5,4 @@ class A {
     }
 }
 
-fun box() = (A.Companion::ok)()
+fun box() = (A.Companion::ok).let { it() }

compiler/testData/codegen/box/callableReference/bound/emptyLHS.kt

@@ -7,11 +7,11 @@ class A {
     val aMemberProperty: Int get() = 42.also { result += "A.amp," }
 
     fun test(): String {
-        (::memberFunction)()
-        (::aExtensionFunction)()
+        (::memberFunction).let { it() }
+        (::aExtensionFunction).let { it() }
 
-        (::memberProperty)()
-        (::aExtensionProperty)()
+        (::memberProperty).let { it() }
+        (::aExtensionProperty).let { it() }
 
         return result
     }
@@ -21,17 +21,17 @@ class A {
         val memberProperty: Int get() = 42.also { result += "B.mp," }
 
         fun test(): String {
-            (::aMemberFunction)()
-            (::aExtensionFunction)()
+            (::aMemberFunction).let { it() }
+            (::aExtensionFunction).let { it() }
 
-            (::aMemberProperty)()
-            (::aExtensionProperty)()
+            (::aMemberProperty).let { it() }
+            (::aExtensionProperty).let { it() }
 
-            (::memberFunction)()
-            (::memberProperty)()
+            (::memberFunction).let { it() }
+            (::memberProperty).let { it() }
 
-            (::bExtensionFunction)()
-            (::bExtensionProperty)()
+            (::bExtensionFunction).let { it() }
+            (::bExtensionProperty).let { it() }
 
             return result
         }
@@ -53,28 +53,28 @@ fun box(): String {
 
     result = ""
     with(A()) {
-        (::memberFunction)()
-        (::aExtensionFunction)()
+        (::memberFunction).let { it() }
+        (::aExtensionFunction).let { it() }
 
-        (::memberProperty)()
-        (::aExtensionProperty)()
+        (::memberProperty).let { it() }
+        (::aExtensionProperty).let { it() }
     }
     if (result != "A.mf,A.ef,A.mp,A.ep,") return "Fail $result"
 
     result = ""
     with(A()) {
         with(B()) {
-            (::aMemberFunction)()
-            (::aExtensionFunction)()
+            (::aMemberFunction).let { it() }
+            (::aExtensionFunction).let { it() }
 
-            (::aMemberProperty)()
-            (::aExtensionProperty)()
+            (::aMemberProperty).let { it() }
+            (::aExtensionProperty).let { it() }
 
-            (::memberFunction)()
-            (::memberProperty)()
+            (::memberFunction).let { it() }
+            (::memberProperty).let { it() }
 
-            (::bExtensionFunction)()
-            (::bExtensionProperty)()
+            (::bExtensionFunction).let { it() }
+            (::bExtensionProperty).let { it() }
         }
     }
     if (result != "A.amf,A.ef,A.amp,A.ep,B.mf,B.mp,B.ef,B.ep,") return "Fail $result"

compiler/testData/codegen/box/callableReference/bound/genericValOnLHS.kt

@@ -7,6 +7,6 @@ class Host {
 
 fun box(): String {
     Generic(Host()).p::class
-    (Generic(Host()).p::t)()
-    return (Generic(Host()).p::v)()
+    (Generic(Host()).p::t).let { it() }
+    return (Generic(Host()).p::v).let { it() }
 }

compiler/testData/codegen/box/callableReference/bound/kt15446.kt

@@ -3,13 +3,13 @@
 fun box(): String {
     val a = intArrayOf(1, 2)
     val b = arrayOf("OK")
-    if ((a::component2)() != 2) {
+    if ((a::component2).let { it() } != 2) {
         return "fail"
     }
 
-    if ((a::get)(1) != 2) {
+    if ((a::get).let { it(1) } != 2) {
         return "fail"
     }
 
-    return (b::get)(0)
+    return (b::get).let { it(0) }
 }

compiler/testData/codegen/box/callableReference/bound/objectReceiver.kt

@@ -3,4 +3,4 @@ object Singleton {
     fun ok() = "OK"
 }
 
-fun box() = (Singleton::ok)()
+fun box() = (Singleton::ok).let { it() }

compiler/testData/codegen/box/callableReference/constructor.kt

@@ -10,6 +10,7 @@ class A {
 // FILE: 1.kt
 
 fun box(): String {
-    (::A)(0.0, 0)
+    val constructor = ::A
+    constructor(0.0, 0)
     return "OK"
 }

compiler/testData/codegen/box/callableReference/function/abstractClassMember.kt

@@ -6,4 +6,4 @@ class B : A() {
     override fun foo() = "OK"
 }
 
-fun box(): String = (A::foo)(B())
+fun box(): String = (A::foo).let { it(B()) }

compiler/testData/codegen/box/callableReference/function/booleanNotIntrinsic.kt

@@ -1,5 +1,5 @@
 fun box(): String {
-    if ((Boolean::not)(true) != false) return "Fail 1"
-    if ((Boolean::not)(false) != true) return "Fail 2"
+    if ((Boolean::not).let { it(true) } != false) return "Fail 1"
+    if ((Boolean::not).let { it(false) } != true) return "Fail 2"
     return "OK"
 }

compiler/testData/codegen/box/callableReference/function/classMemberFromClass.kt

@@ -1,7 +1,7 @@
 class A {
     fun foo(k: Int) = k
 
-    fun result() = (A::foo)(this, 111)
+    fun result() = (A::foo).let { it(this, 111) }
 }
 
 fun box(): String {

compiler/testData/codegen/box/callableReference/function/classMemberFromExtension.kt

@@ -3,7 +3,7 @@ class A {
     fun k(k: Int) = k
 }
 
-fun A.foo() = (A::o)(this) + (A::k)(this, 222)
+fun A.foo() = (A::o).let { it(this) } + (A::k).let { it(this, 222) }
 
 fun box(): String {
     val result = A().foo()

compiler/testData/codegen/box/callableReference/function/constructorFromTopLevelNoArgs.kt

@@ -2,4 +2,4 @@ class A {
     var result = "OK"
 }
 
-fun box() = (::A)().result
+fun box() = (::A).let { it() }.result

compiler/testData/codegen/box/callableReference/function/constructorFromTopLevelOneStringArg.kt

@@ -1,3 +1,3 @@
 class A(val result: String)
 
-fun box() = (::A)("OK").result
+fun box() = (::A).let { it("OK") }.result

compiler/testData/codegen/box/callableReference/function/equalsIntrinsic.kt

@@ -1,3 +1,3 @@
 class A
 
-fun box() = if ((A::equals)(A(), A())) "Fail" else "OK"
+fun box() = if ((A::equals).let { it(A(), A()) }) "Fail" else "OK"

compiler/testData/codegen/box/callableReference/function/extensionFromClass.kt

@@ -1,5 +1,5 @@
 class A {
-    fun result() = (A::foo)(this, "OK")
+    fun result() = (A::foo).let { it(this, "OK") }
 }
 
 fun A.foo(x: String) = x

compiler/testData/codegen/box/callableReference/function/extensionFromExtension.kt

@@ -1,6 +1,6 @@
 class A
 
-fun A.foo() = (A::bar)(this, "OK")
+fun A.foo() = (A::bar).let { it(this, "OK") }
 
 fun A.bar(x: String) = x
 

compiler/testData/codegen/box/callableReference/function/genericMember.kt

@@ -2,4 +2,4 @@ class A<T>(val t: T) {
     fun foo(): T = t
 }
 
-fun box() = (A<String>::foo)(A("OK"))
+fun box() = (A<String>::foo).let { it(A("OK")) }

compiler/testData/codegen/box/callableReference/function/innerConstructorFromClass.kt

@@ -4,7 +4,7 @@ class A {
         val k = 222
     }
     
-    fun result() = (A::Inner)(this).o + (A::Inner)(this).k
+    fun result() = (A::Inner).let { it(this) }.o + (A::Inner).let { it(this) }.k
 }
 
 fun box(): String {

compiler/testData/codegen/box/callableReference/function/innerConstructorFromExtension.kt

@@ -5,7 +5,7 @@ class A {
     }
 }
 
-fun A.foo() = (A::Inner)(this).o + (A::Inner)(this).k
+fun A.foo() = (A::Inner).let { it(this) }.o + (A::Inner).let { it(this) }.k
 
 fun box(): String {
     val result = A().foo()

compiler/testData/codegen/box/callableReference/function/innerConstructorFromTopLevelNoArgs.kt

@@ -6,7 +6,7 @@ class A {
 }
 
 fun box(): String {
-    val result = (A::Inner)((::A)()).o + (A::Inner)(A()).k
+    val result = (A::Inner).let { c -> c((::A).let { it() }).o } + (A::Inner).let { it(A()) }.k
     if (result != 333) return "Fail $result"
     return "OK"
 }

compiler/testData/codegen/box/callableReference/function/innerConstructorFromTopLevelOneStringArg.kt

@@ -3,7 +3,10 @@ class A {
 }
 
 fun box(): String {
-    val result = (A::Inner)((::A)(), 111).result + (A::Inner)(A(), 222).result
+    val result = (A::Inner).let { c -> c((::A).let { it() }, 111) }.result + (A::Inner).let { it(A(), 222) }.result
     if (result != 333) return "Fail $result"
     return "OK"
 }
+
+// CHECK_BYTECODE_TEXT
+// 3 Function[^.\n]*\.invoke

compiler/testData/codegen/box/callableReference/function/javaCollectionsStaticMethod.kt

@@ -10,6 +10,6 @@ fun box(): String {
     numbers.add(1)
     numbers.add(2)
     numbers.add(3)
-    (Collections::rotate)(numbers, 1)
+    (Collections::rotate).let { it(numbers, 1) }
     return if ("$numbers" == "[3, 1, 2]") "OK" else "Fail $numbers"
 }

compiler/testData/codegen/box/callableReference/function/local/constructor.kt

@@ -3,5 +3,5 @@ fun box(): String {
         val result = "OK"
     }
 
-    return (::A)().result
+    return (::A).let { it() }.result
 }

compiler/testData/codegen/box/callableReference/function/local/constructorWithInitializer.kt

@@ -6,5 +6,5 @@ fun box(): String {
         }
     }
 
-    return (::A)().result
+    return (::A).let { it() }.result
 }

compiler/testData/codegen/box/callableReference/function/local/extension.kt

@@ -2,5 +2,5 @@ class A
 
 fun box(): String {
     fun A.foo() = "OK"
-    return (A::foo)(A())
+    return (A::foo).let { it(A()) }
 }

compiler/testData/codegen/box/callableReference/function/local/extensionToLocalClass.kt

@@ -1,5 +1,5 @@
 fun box(): String {
     class A
     fun A.foo() = "OK"
-    return (A::foo)((::A)())
+    return (A::foo).let { c -> c((::A).let { it() }) }
 }

compiler/testData/codegen/box/callableReference/function/local/extensionToPrimitive.kt

@@ -1,4 +1,4 @@
 fun box(): String {
     fun Int.is42With(that: Int) = this + 2 * that == 42
-    return if ((Int::is42With)(16, 13)) "OK" else "Fail"
+    return if ((Int::is42With).let { it(16, 13) }) "OK" else "Fail"
 }

compiler/testData/codegen/box/callableReference/function/local/recursiveClosure.kt

@@ -1,7 +1,7 @@
 fun foo(until: Int): String {
     fun bar(x: Int): String =
         if (x == until) "OK" else bar(x + 1)
-    return (::bar)(0)
+    return (::bar).let { it(0) }
 }
 
 fun box() = foo(10)

compiler/testData/codegen/box/callableReference/function/local/simple.kt

@@ -1,4 +1,4 @@
 fun box(): String {
     fun foo() = "OK"
-    return (::foo)()
+    return (::foo).let { it() }
 }

compiler/testData/codegen/box/callableReference/function/local/simpleClosure.kt

@@ -3,5 +3,5 @@ fun box(): String {
 
     fun foo() = result
 
-    return (::foo)()
+    return (::foo).let { it() }
 }

compiler/testData/codegen/box/callableReference/function/local/simpleWithArg.kt

@@ -1,4 +1,4 @@
 fun box(): String {
     fun foo(s: String) = s
-    return (::foo)("OK")
+    return (::foo).let { it("OK") }
 }

compiler/testData/codegen/box/callableReference/function/nestedConstructorFromClass.kt

@@ -4,7 +4,7 @@ class A {
         val k = 222
     }
     
-    fun result() = (::Nested)().o + (A::Nested)().k
+    fun result() = (::Nested).let { it() }.o + (A::Nested).let { it() }.k
 }
 
 fun box(): String {

compiler/testData/codegen/box/callableReference/function/nestedConstructorFromTopLevelNoArgs.kt

@@ -4,4 +4,4 @@ class A {
     }
 }
 
-fun box() = (A::Nested)().result
+fun box() = (A::Nested).let { it() }.result

compiler/testData/codegen/box/callableReference/function/nestedConstructorFromTopLevelOneStringArg.kt

@@ -2,4 +2,4 @@ class A {
     class Nested(val result: String)
 }
 
-fun box() = (A::Nested)("OK").result
+fun box() = (A::Nested).let { it("OK") }.result

compiler/testData/codegen/box/callableReference/function/privateClassMember.kt

@@ -1,7 +1,7 @@
 class A {
     private fun foo() = "OK"
 
-    fun bar() = (A::foo)(this)
+    fun bar() = (A::foo).let { it(this) }
 }
 
 fun box() = A().bar()

compiler/testData/codegen/box/callableReference/function/topLevelFromClass.kt

@@ -5,7 +5,7 @@ fun <T> run(arg1: T, arg2: T, funRef:(T,T) -> T): T {
 fun foo(o: Int, k: Int) = o + k
 
 class A {
-    fun bar() = (::foo)(111, 222)
+    fun bar() = (::foo).let { it(111, 222) }
 }
 
 fun box(): String {

compiler/testData/codegen/box/callableReference/function/topLevelFromExtension.kt

@@ -6,7 +6,7 @@ fun foo(o: Int, k: Int) = o + k
 
 class A
 
-fun A.bar() = (::foo)(111, 222)
+fun A.bar() = (::foo).let { it(111, 222) }
 
 fun box(): String {
     val result = A().bar()

compiler/testData/codegen/box/callableReference/function/traitImplMethodWithClassReceiver.kt

@@ -4,7 +4,7 @@ interface T {
 
 class B : T {
     inner class C {
-        fun bar() = (T::foo)(this@B)
+        fun bar() = (T::foo).let { it(this@B) }
     }
 }
 

compiler/testData/codegen/box/callableReference/function/traitMember.kt

@@ -6,4 +6,4 @@ class B : A {
     override fun foo() = "OK"
 }
 
-fun box() = (A::foo)(B())
+fun box() = (A::foo).let { it(B()) }

compiler/testData/codegen/box/callableReference/staticMethod.kt

@@ -13,6 +13,6 @@ class A {
 
 fun box(): String {
     val args = arrayOf("Fail")
-    (A::main)(args)
+    (A::main).let { it(args) }
     return args[0]
 }