Handle withIndex() on Iterables (including progressions) and Sequences

in ForLoopsLowering.

compiler/testData/codegen/bytecodeText/forLoop/forInProgressionWithIndex/forInDownToWithIndex.kt

@@ -0,0 +1,28 @@
+fun box(): String {
+    for ((i, v) in (7 downTo 4).withIndex()) {
+    }
+
+    return "OK"
+}
+
+// 0 withIndex
+// 0 component1
+// 0 component2
+
+// The ICONST_0 is for initializing the index in the lowered for-loop.
+// 1 ICONST_0
+
+// JVM_TEMPLATES
+// 1 iterator
+// 1 hasNext
+// 1 next
+
+// JVM_IR_TEMPLATES
+// 0 iterator
+// 0 hasNext
+// 0 next
+// 0 getStart
+// 0 getEnd
+// 0 getFirst
+// 0 getLast
+// 0 getStep

compiler/testData/codegen/bytecodeText/forLoop/forInProgressionWithIndex/forInIndicesWithIndex.kt

@@ -0,0 +1,29 @@
+fun box(): String {
+    for ((i, v) in listOf(4, 5, 6, 7).indices.withIndex()) {
+    }
+
+    return "OK"
+}
+
+// 0 withIndex
+// 0 component1
+// 0 component2
+
+// The 1st ICONST_0 is for initializing the list. 2nd is for initializing the index in the lowered for-loop.
+// 2 ICONST_0
+
+// JVM_TEMPLATES
+// 1 iterator
+// 1 hasNext
+// 1 next
+
+// JVM_IR_TEMPLATES
+// 0 iterator
+// 0 hasNext
+// 0 next
+// 0 getStart
+// 0 getEnd
+// 0 getFirst
+// 0 getLast
+// 0 getStep
+// 0 getIndices

compiler/testData/codegen/bytecodeText/forLoop/forInProgressionWithIndex/forInRangeToWithIndex.kt

@@ -0,0 +1,28 @@
+fun box(): String {
+    for ((i, v) in (4..7).withIndex()) {
+    }
+
+    return "OK"
+}
+
+// 0 withIndex
+// 0 component1
+// 0 component2
+
+// The ICONST_0 is for initializing the index in the lowered for-loop.
+// 1 ICONST_0
+
+// JVM_TEMPLATES
+// 1 iterator
+// 1 hasNext
+// 1 next
+
+// JVM_IR_TEMPLATES
+// 0 iterator
+// 0 hasNext
+// 0 next
+// 0 getStart
+// 0 getEnd
+// 0 getFirst
+// 0 getLast
+// 0 getStep

compiler/testData/codegen/bytecodeText/forLoop/forInProgressionWithIndex/forInReversedStepWithIndex.kt

@@ -0,0 +1,30 @@
+fun box(): String {
+    for ((i, v) in ((4..11).reversed() step 2).withIndex()) {
+    }
+
+    return "OK"
+}
+
+// 0 withIndex
+// 0 component1
+// 0 component2
+
+// The ICONST_0 is for initializing the index in the lowered for-loop.
+// 1 ICONST_0
+
+// JVM_TEMPLATES
+// 1 iterator
+// 1 hasNext
+// 1 next
+
+// JVM_IR_TEMPLATES
+// 0 iterator
+// 0 hasNext
+// 0 next
+// 0 getStart
+// 0 getEnd
+// 0 getFirst
+// 0 getLast
+// 0 getStep
+// 0 reversed
+// 0 step

compiler/testData/codegen/bytecodeText/forLoop/forInProgressionWithIndex/forInReversedWithIndex.kt

@@ -0,0 +1,29 @@
+fun box(): String {
+    for ((i, v) in (4..7).reversed().withIndex()) {
+    }
+
+    return "OK"
+}
+
+// 0 withIndex
+// 0 component1
+// 0 component2
+
+// The ICONST_0 is for initializing the index in the lowered for-loop.
+// 1 ICONST_0
+
+// JVM_TEMPLATES
+// 1 iterator
+// 1 hasNext
+// 1 next
+
+// JVM_IR_TEMPLATES
+// 0 iterator
+// 0 hasNext
+// 0 next
+// 0 getStart
+// 0 getEnd
+// 0 getFirst
+// 0 getLast
+// 0 getStep
+// 0 reversed

compiler/testData/codegen/bytecodeText/forLoop/forInProgressionWithIndex/forInStepReversedWithIndex.kt

@@ -0,0 +1,30 @@
+fun box(): String {
+    for ((i, v) in (4..11 step 2).reversed().withIndex()) {
+    }
+
+    return "OK"
+}
+
+// 0 withIndex
+// 0 component1
+// 0 component2
+
+// The ICONST_0 is for initializing the index in the lowered for-loop.
+// 1 ICONST_0
+
+// JVM_TEMPLATES
+// 1 iterator
+// 1 hasNext
+// 1 next
+
+// JVM_IR_TEMPLATES
+// 0 iterator
+// 0 hasNext
+// 0 next
+// 0 getStart
+// 0 getEnd
+// 0 getFirst
+// 0 getLast
+// 0 getStep
+// 0 reversed
+// 0 step

compiler/testData/codegen/bytecodeText/forLoop/forInProgressionWithIndex/forInStepWithIndex.kt

@@ -0,0 +1,29 @@
+fun box(): String {
+    for ((i, v) in (4..11 step 2).withIndex()) {
+    }
+
+    return "OK"
+}
+
+// 0 withIndex
+// 0 component1
+// 0 component2
+
+// The ICONST_0 is for initializing the index in the lowered for-loop.
+// 1 ICONST_0
+
+// JVM_TEMPLATES
+// 1 iterator
+// 1 hasNext
+// 1 next
+
+// JVM_IR_TEMPLATES
+// 0 iterator
+// 0 hasNext
+// 0 next
+// 0 getStart
+// 0 getEnd
+// 0 getFirst
+// 0 getLast
+// 0 getStep
+// 0 step

compiler/testData/codegen/bytecodeText/forLoop/forInProgressionWithIndex/forInUntilWithIndex.kt

@@ -0,0 +1,28 @@
+fun box(): String {
+    for ((i, v) in (4 until 8).withIndex()) {
+    }
+
+    return "OK"
+}
+
+// 0 withIndex
+// 0 component1
+// 0 component2
+
+// The ICONST_0 is for initializing the index in the lowered for-loop.
+// 1 ICONST_0
+
+// JVM_TEMPLATES
+// 1 iterator
+// 1 hasNext
+// 1 next
+
+// JVM_IR_TEMPLATES
+// 0 iterator
+// 0 hasNext
+// 0 next
+// 0 getStart
+// 0 getEnd
+// 0 getFirst
+// 0 getLast
+// 0 getStep

compiler/testData/codegen/bytecodeText/forLoop/forInProgressionWithIndex/forInWithIndexNoIndexOrElementVar.kt

@@ -0,0 +1,28 @@
+fun box(): String {
+    for ((_, _) in (4..7).withIndex()) {
+    }
+
+    return "OK"
+}
+
+// 0 withIndex
+// 0 component1
+// 0 component2
+
+// The ICONST_0 is for initializing the index in the lowered for-loop.
+// 1 ICONST_0
+
+// JVM_TEMPLATES
+// 1 iterator
+// 1 hasNext
+// 1 next
+
+// JVM_IR_TEMPLATES
+// 0 iterator
+// 0 hasNext
+// 0 next
+// 0 getStart
+// 0 getEnd
+// 0 getFirst
+// 0 getLast
+// 0 getStep

compiler/testData/codegen/bytecodeText/forLoop/forInProgressionWithIndex/forInWithIndexNotDestructured.kt

@@ -0,0 +1,15 @@
+fun box(): String {
+    for (iv in (4..7).withIndex()) {
+    }
+
+    return "OK"
+}
+
+// We do not optimize `withIndex()` if the loop variable is not destructured
+
+// 1 withIndex
+// 1 iterator
+// 1 hasNext
+// 1 next
+// 0 component1
+// 0 component2

compiler/testData/codegen/bytecodeText/forLoop/forInProgressionWithIndex/forInWithIndexReversed.kt

@@ -0,0 +1,16 @@
+fun box(): String {
+    for ((i, v) in (4..7).withIndex().reversed()) {
+    }
+
+    return "OK"
+}
+
+// We do not optimize `withIndex().reversed()`
+
+// 1 withIndex
+// 1 iterator
+// 1 hasNext
+// 1 next
+// 1 component1
+// 1 component2
+// 1 reversed

compiler/testData/codegen/bytecodeText/forLoop/forInProgressionWithIndex/forInWithIndexWithIndex.kt

@@ -0,0 +1,18 @@
+fun box(): String {
+    for ((outer, iv) in (4..7).withIndex().withIndex()) {
+    }
+
+    return "OK"
+}
+
+// We optimize the outer `withIndex()` and treat the inner one as an Iterable
+
+// 1 withIndex
+// 1 iterator
+// 1 hasNext
+// 1 next
+// 0 component1
+// 0 component2
+
+// The ICONST_0 is for initializing the index in the lowered for-loop.
+// 1 ICONST_0