If branch conditions' one successor is dominating another non-latch successor then...

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@65902 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Transforms/Scalar/LoopIndexSplit.cpp b/lib/Transforms/Scalar/LoopIndexSplit.cpp
index 6311e171e0d8900d385f638cd0585398897a8f26..e93d448cc1be826f5f71310d89aacfd3b56a8880 100644 (file)
--- a/lib/Transforms/Scalar/LoopIndexSplit.cpp
+++ b/lib/Transforms/Scalar/LoopIndexSplit.cpp
@@ -532,6 +532,21 @@ bool LoopIndexSplit::updateLoopIterationSpace() {
   BasicBlock *ExitingBlock = ExitCondition->getParent();
   if (!cleanBlock(ExitingBlock)) return false;
 
+  // If the merge point for BR is not loop latch then skip this loop.
+  if (BR->getSuccessor(0) != Latch) {
+    DominanceFrontier::iterator DF0 = DF->find(BR->getSuccessor(0));
+    assert (DF0 != DF->end() && "Unable to find dominance frontier");
+    if (!DF0->second.count(Latch))
+      return false;
+  }
+  
+  if (BR->getSuccessor(1) != Latch) {
+    DominanceFrontier::iterator DF1 = DF->find(BR->getSuccessor(1));
+    assert (DF1 != DF->end() && "Unable to find dominance frontier");
+    if (!DF1->second.count(Latch))
+      return false;
+  }
+    
   // Verify that loop exiting block has only two predecessor, where one pred
   // is split condition block. The other predecessor will become exiting block's
   // dominator after CFG is updated. TODO : Handle CFG's where exiting block has

diff --git a/test/Transforms/LoopIndexSplit/2009-03-02-UpdateIterationSpace-crash.ll b/test/Transforms/LoopIndexSplit/2009-03-02-UpdateIterationSpace-crash.ll
new file mode 100644 (file)
index 0000000..73113e7
--- /dev/null
+++ b/test/Transforms/LoopIndexSplit/2009-03-02-UpdateIterationSpace-crash.ll
@@ -0,0 +1,64 @@
+; RUN: llvm-as < %s | opt -loop-index-split -disable-output
+       %struct.CGPoint = type { double, double }
+       %struct.IBCFMutableDictionary = type { %struct.NSMutableArray, %struct.__CFDictionary*, %struct.NSSortDescriptor*, %struct.NSSortDescriptor* }
+       %struct.IBInspectorMode = type opaque
+       %struct.IBInspectorModeView = type { %struct.NSView, %struct.NSArray*, %struct.IBCFMutableDictionary*, %struct.IBInspectorMode*, %struct.IBInspectorMode*, %struct.IBInspectorMode*, %struct.objc_selector*, %struct.NSObject* }
+       %struct.NSArray = type { %struct.NSObject }
+       %struct.NSImage = type { %struct.NSObject, %struct.NSArray*, %struct.CGPoint, %struct.__imageFlags, %struct.NSObject*, %struct._NSImageAuxiliary* }
+       %struct.NSMutableArray = type { %struct.NSArray }
+       %struct.NSObject = type { %struct.objc_class* }
+       %struct.NSRect = type { %struct.CGPoint, %struct.CGPoint }
+       %struct.NSResponder = type { %struct.NSObject, %struct.NSObject* }
+       %struct.NSSortDescriptor = type { %struct.NSObject, i64, %struct.NSArray*, %struct.objc_selector*, %struct.NSObject* }
+       %struct.NSURL = type { %struct.NSObject, %struct.NSArray*, %struct.NSURL*, i8*, i8* }
+       %struct.NSView = type { %struct.NSResponder, %struct.NSRect, %struct.NSRect, %struct.NSObject*, %struct.NSObject*, %struct.NSWindow*, %struct.NSObject*, %struct.NSObject*, %struct.NSObject*, %struct.NSObject*, %struct._NSViewAuxiliary*, %struct._VFlags, %struct.__VFlags2 }
+       %struct.NSWindow = type { %struct.NSResponder, %struct.NSRect, %struct.NSObject*, %struct.NSObject*, %struct.NSResponder*, %struct.NSView*, %struct.NSView*, %struct.NSObject*, %struct.NSObject*, i32, i64, i32, %struct.NSArray*, %struct.NSObject*, i8, i8, i8, i8, i8*, i8*, %struct.NSImage*, i32, %struct.NSMutableArray*, %struct.NSURL*, %struct.CGPoint*, %struct.NSArray*, %struct.NSArray*, %struct.__wFlags, %struct.NSObject*, %struct.NSView*, %struct.NSWindowAuxiliary* }
+       %struct.NSWindowAuxiliary = type opaque
+       %struct._NSImageAuxiliary = type opaque
+       %struct._NSViewAuxiliary = type opaque
+       %struct._VFlags = type <{ i8, i8, i8, i8 }>
+       %struct.__CFDictionary = type opaque
+       %struct.__VFlags2 = type <{ i32 }>
+       %struct.__imageFlags = type <{ i8, [3 x i8] }>
+       %struct.__wFlags = type <{ i8, i8, i8, i8, i8, i8, i8, i8 }>
+       %struct.objc_class = type opaque
+       %struct.objc_selector = type opaque
+
+define %struct.NSArray* @"\01-[IBInspectorModeView calculateModeRects]"(%struct.IBInspectorModeView* %self, %struct.objc_selector* %_cmd) optsize ssp {
+entry:
+       br i1 false, label %bb7, label %bb
+
+bb:            ; preds = %entry
+       br i1 false, label %bb.nph, label %bb7.loopexit
+
+bb.nph:                ; preds = %bb
+       br label %bb1
+
+bb1:           ; preds = %bb6, %bb.nph
+       %midx.01 = phi i64 [ %3, %bb6 ], [ 0, %bb.nph ]         ; <i64> [#uses=3]
+       %0 = icmp sge i64 %midx.01, 0           ; <i1> [#uses=1]
+       %1 = icmp sle i64 %midx.01, 0           ; <i1> [#uses=1]
+       %2 = and i1 %0, %1              ; <i1> [#uses=1]
+       br i1 %2, label %bb4, label %bb5
+
+bb4:           ; preds = %bb1
+       br label %bb5
+
+bb5:           ; preds = %bb4, %bb1
+       %modeWidth.0 = phi double [ 0.000000e+00, %bb1 ], [ 0.000000e+00, %bb4 ]                ; <double> [#uses=0]
+       %3 = add i64 %midx.01, 1                ; <i64> [#uses=1]
+       br label %bb6
+
+bb6:           ; preds = %bb5
+       %4 = icmp slt i64 0, 0          ; <i1> [#uses=1]
+       br i1 %4, label %bb1, label %bb6.bb7.loopexit_crit_edge
+
+bb6.bb7.loopexit_crit_edge:            ; preds = %bb6
+       br label %bb7.loopexit
+
+bb7.loopexit:          ; preds = %bb6.bb7.loopexit_crit_edge, %bb
+       br label %bb7
+
+bb7:           ; preds = %bb7.loopexit, %entry
+       ret %struct.NSArray* null
+}