From 607fe5bb280a3d8709820d2a77d75531b500fb04 Mon Sep 17 00:00:00 2001
From: Michael Zolotukhin <mzolotukhin@apple.com>
Date: Wed, 29 Jul 2015 18:10:33 +0000
Subject: [PATCH] [Unroll] Handle SwitchInst properly.
Previously successor selection was simply wrong.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243545 91177308-0d34-0410-b5e6-96231b3b80d8
---
lib/Transforms/Scalar/LoopUnrollPass.cpp | 4 ++--
.../LoopUnroll/full-unroll-crashers.ll | 24 +++++++++++++++++++
2 files changed, 26 insertions(+), 2 deletions(-)
diff --git a/lib/Transforms/Scalar/LoopUnrollPass.cpp b/lib/Transforms/Scalar/LoopUnrollPass.cpp
index 25b0877a4f4..6b64d4e6ecf 100644
--- a/lib/Transforms/Scalar/LoopUnrollPass.cpp
+++ b/lib/Transforms/Scalar/LoopUnrollPass.cpp
@@ -619,8 +619,8 @@ analyzeLoopUnrollCost(const Loop *L, unsigned TripCount, ScalarEvolution &SE,
if (isa<UndefValue>(SimpleCond))
Succ = SI->getSuccessor(0);
else
- Succ =
- SI->getSuccessor(cast<ConstantInt>(SimpleCond)->getSExtValue());
+ Succ = SI->findCaseValue(cast<ConstantInt>(SimpleCond))
+ .getCaseSuccessor();
if (L->contains(Succ))
BBWorklist.insert(Succ);
continue;
diff --git a/test/Transforms/LoopUnroll/full-unroll-crashers.ll b/test/Transforms/LoopUnroll/full-unroll-crashers.ll
index 0bf13278e83..eebf5a0a2f2 100644
--- a/test/Transforms/LoopUnroll/full-unroll-crashers.ll
+++ b/test/Transforms/LoopUnroll/full-unroll-crashers.ll
@@ -57,3 +57,27 @@ for.inc: ; preds = %for.body, %if.then
for.end: ; preds = %for.inc
ret void
}
+
+define void @switch() {
+entry:
+ br label %for.body
+
+for.body:
+ %iv.0 = phi i64 [ 0, %entry ], [ %iv.1, %for.inc ]
+ %arrayidx1 = getelementptr inbounds [10 x i32], [10 x i32]* @known_constant, i64 0, i64 %iv.0
+ %x1 = load i32, i32* %arrayidx1, align 4
+ switch i32 %x1, label %l1 [
+ ]
+
+l1:
+ %x2 = add i32 %x1, 2
+ br label %for.inc
+
+for.inc:
+ %iv.1 = add nuw nsw i64 %iv.0, 1
+ %exitcond = icmp eq i64 %iv.1, 10
+ br i1 %exitcond, label %for.end, label %for.body
+
+for.end:
+ ret void
+}
--
2.34.1