From 75f9532959b922c0bbb993f843036de4bf7bdf61 Mon Sep 17 00:00:00 2001
From: Mads Ager <ager@google.com>
Date: Wed, 4 Sep 2019 08:38:54 +0200
Subject: [PATCH] [IR] Avoid duplicate IR elements in for loops lowering.

---
 .../kotlin/backend/common/lower/loops/HeaderProcessor.kt    | 6 +++---
 .../backend/common/lower/loops/ProgressionHandlers.kt       | 3 ++-
 2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/loops/HeaderProcessor.kt b/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/loops/HeaderProcessor.kt
index f49e3fb5ff7..59745b8c601 100644
--- a/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/loops/HeaderProcessor.kt
+++ b/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/loops/HeaderProcessor.kt
@@ -102,12 +102,12 @@ internal sealed class ForLoopHeader(
                     //   // (use `<` if last is exclusive)
                     //   (step > 0 && inductionVar <= last) || (step < 0 || last <= inductionVar)
                     val stepKotlinType = progressionType.stepType(builtIns).toKotlinType()
-                    val zero = if (progressionType == ProgressionType.LONG_PROGRESSION) irLong(0) else irInt(0)
+                    val isLong = progressionType == ProgressionType.LONG_PROGRESSION
                     context.oror(
                         context.andand(
                             irCall(builtIns.greaterFunByOperandType[stepKotlinType]!!).apply {
                                 putValueArgument(0, irGet(step))
-                                putValueArgument(1, zero)
+                                putValueArgument(1, if (isLong) irLong(0) else irInt(0))
                             },
                             irCall(compFun).apply {
                                 putValueArgument(0, irGet(inductionVariable))
@@ -116,7 +116,7 @@ internal sealed class ForLoopHeader(
                         context.andand(
                             irCall(builtIns.lessFunByOperandType[stepKotlinType]!!).apply {
                                 putValueArgument(0, irGet(step))
-                                putValueArgument(1, zero)
+                                putValueArgument(1, if (isLong) irLong(0) else irInt(0))
                             },
                             irCall(compFun).apply {
                                 putValueArgument(0, irGet(last))
diff --git a/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/loops/ProgressionHandlers.kt b/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/loops/ProgressionHandlers.kt
index 940be685991..8985adfa6db 100644
--- a/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/loops/ProgressionHandlers.kt
+++ b/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/loops/ProgressionHandlers.kt
@@ -153,7 +153,8 @@ internal class UntilHandler(private val context: CommonBackendContext, private v
                     it == null && isAdditionalNotEmptyConditionNeeded(receiverValue.type, untilArg.type) ->
                         // Condition is needed and untilArg is non-const.
                         // Build the additional "not empty" condition: `untilArg != MIN_VALUE`.
-                        irNotEquals(untilArgExpression, minValueIrConst)
+                        // Make sure to copy untilArgExpression as it is also used in `last`.
+                        irNotEquals(untilArgExpression.deepCopyWithSymbols(), minValueIrConst)
                     it == minValueAsLong ->
                         // Hardcode "false" as additional condition so that the progression is considered empty.
                         // The entire lowered loop becomes a candidate for dead code elimination, depending on backend.