From: Devang Patel <dpatel@apple.com>
Date: Wed, 13 Feb 2008 22:23:07 +0000 (+0000)
Subject: A loop latch phi node may have uses inside loop, not just in loop header.
X-Git-Url: http://plrg.eecs.uci.edu/git/?a=commitdiff_plain;h=ea069065592a43cabe4548299828eb9b26785da7;p=oota-llvm.git

A loop latch phi node may have uses inside loop, not just in loop header.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47093 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Transforms/Scalar/LoopIndexSplit.cpp b/lib/Transforms/Scalar/LoopIndexSplit.cpp
index 383415b228b..a0bfe4f0822 100644
--- a/lib/Transforms/Scalar/LoopIndexSplit.cpp
+++ b/lib/Transforms/Scalar/LoopIndexSplit.cpp
@@ -151,7 +151,7 @@ namespace {
     /// Update ExitBB PHINodes' to reflect this change.
     void updatePHINodes(BasicBlock *ExitBB, BasicBlock *Latch, 
                         BasicBlock *Header,
-                        PHINode *IV, Instruction *IVIncrement);
+                        PHINode *IV, Instruction *IVIncrement, Loop *LP);
 
     /// moveExitCondition - Move exit condition EC into split condition block CondBB.
     void moveExitCondition(BasicBlock *CondBB, BasicBlock *ActiveBB,
@@ -1597,7 +1597,7 @@ void LoopIndexSplit::moveExitCondition(BasicBlock *CondBB, BasicBlock *ActiveBB,
   new BranchInst(OrigDestBB, ExitingBB);
 
   // Update PHINodes
-  updatePHINodes(ExitBB, ExitingBB, CondBB, IV, IVAdd);
+  updatePHINodes(ExitBB, ExitingBB, CondBB, IV, IVAdd, LP);
 
   // Fix dominator info.
   // ExitBB is now dominated by CondBB
@@ -1637,7 +1637,8 @@ void LoopIndexSplit::moveExitCondition(BasicBlock *CondBB, BasicBlock *ActiveBB,
 /// Update ExitBB PHINodes' to reflect this change.
 void LoopIndexSplit::updatePHINodes(BasicBlock *ExitBB, BasicBlock *Latch, 
                                     BasicBlock *Header,
-                                    PHINode *IV, Instruction *IVIncrement) {
+                                    PHINode *IV, Instruction *IVIncrement,
+                                    Loop *LP) {
 
   for (BasicBlock::iterator BI = ExitBB->begin(), BE = ExitBB->end(); 
        BI != BE; ++BI) {
@@ -1653,7 +1654,7 @@ void LoopIndexSplit::updatePHINodes(BasicBlock *ExitBB, BasicBlock *Latch,
       for (Value::use_iterator UI = PHV->use_begin(), E = PHV->use_end(); 
            UI != E; ++UI) 
         if (PHINode *U = dyn_cast<PHINode>(*UI)) 
-          if (U->getParent() == Header) {
+          if (LP->contains(U->getParent())) {
             NewV = U;
             break;
           }
diff --git a/test/Transforms/LoopIndexSplit/2008-02-13-LoopLatchPHI.ll b/test/Transforms/LoopIndexSplit/2008-02-13-LoopLatchPHI.ll
new file mode 100644
index 00000000000..393299f3e09
--- /dev/null
+++ b/test/Transforms/LoopIndexSplit/2008-02-13-LoopLatchPHI.ll
@@ -0,0 +1,74 @@
+; RUN: llvm-as < %s | opt -loop-index-split -disable-output
+; PR 2011
+	%struct.CLAUSE_HELP = type { i32, i32, i32, i32, i32*, i32, %struct.LIST_NODE*, %struct.LIST_NODE*, i32, i32, %struct.LITERAL_HELP**, i32, i32, i32, i32 }
+	%struct.LIST_NODE = type { %struct.LIST_NODE*, i8* }
+	%struct.LITERAL_HELP = type { i32, i32, i32, %struct.CLAUSE_HELP*, %struct.term* }
+	%struct.anon = type { %struct.LIST_NODE* }
+	%struct.st = type { %struct.subst*, %struct.LIST_NODE*, %struct.LIST_NODE*, i16, i16 }
+	%struct.subst = type { %struct.subst*, i32, %struct.term* }
+	%struct.term = type { i32, %struct.anon, %struct.LIST_NODE*, i32, i32 }
+
+define fastcc %struct.LIST_NODE* @inf_HyperResolvents(%struct.CLAUSE_HELP* %Clause, %struct.subst* %Subst, %struct.LIST_NODE* %Restlits, i32 %GlobalMaxVar, %struct.LIST_NODE* %FoundMap, i32 %StrictlyMaximal, { %struct.st*, [3001 x %struct.term*], [4000 x %struct.term*], i32 }* %Index, i32* %Flags, i32* %Precedence) nounwind  {
+entry:
+	br i1 false, label %bb960, label %bb885
+
+bb885:		; preds = %entry
+	ret %struct.LIST_NODE* null
+
+bb960:		; preds = %entry
+	br i1 false, label %bb1097, label %bb1005.preheader
+
+bb1005.preheader:		; preds = %bb960
+	ret %struct.LIST_NODE* null
+
+bb1097:		; preds = %bb960
+	br i1 false, label %bb1269.preheader, label %bb1141.preheader
+
+bb1141.preheader:		; preds = %bb1097
+	ret %struct.LIST_NODE* null
+
+bb1269.preheader:		; preds = %bb1097
+	br i1 false, label %bb1318, label %bb1281
+
+bb1281:		; preds = %bb1269.preheader
+	ret %struct.LIST_NODE* null
+
+bb1318:		; preds = %bb1269.preheader
+	br i1 false, label %bb1459, label %bb.nph52
+
+bb.nph52:		; preds = %bb1318
+	ret %struct.LIST_NODE* null
+
+bb1459:		; preds = %bb1318
+	br i1 false, label %bb1553, label %bb.nph62
+
+bb.nph62:		; preds = %bb1459
+	ret %struct.LIST_NODE* null
+
+bb1553:		; preds = %bb1669, %bb1459
+	%j295.0.reg2mem.0 = phi i32 [ %storemerge110, %bb1669 ], [ 0, %bb1459 ]		; <i32> [#uses=2]
+	%Constraint403.2.reg2mem.0 = phi %struct.LIST_NODE* [ %Constraint403.1.reg2mem.0, %bb1669 ], [ null, %bb1459 ]		; <%struct.LIST_NODE*> [#uses=1]
+	br i1 false, label %bb1588, label %bb1616
+
+bb1588:		; preds = %bb1553
+	br label %bb1616
+
+bb1616:		; preds = %bb1588, %bb1553
+	%tmp1629 = icmp sgt i32 %j295.0.reg2mem.0, 0		; <i1> [#uses=1]
+	br i1 %tmp1629, label %bb1649, label %bb1632
+
+bb1632:		; preds = %bb1616
+	br label %bb1669
+
+bb1649:		; preds = %bb1616
+	br label %bb1669
+
+bb1669:		; preds = %bb1649, %bb1632
+	%Constraint403.1.reg2mem.0 = phi %struct.LIST_NODE* [ null, %bb1632 ], [ %Constraint403.2.reg2mem.0, %bb1649 ]		; <%struct.LIST_NODE*> [#uses=1]
+	%storemerge110 = add i32 %j295.0.reg2mem.0, 1		; <i32> [#uses=2]
+	%tmp1672 = icmp sgt i32 %storemerge110, 0		; <i1> [#uses=1]
+	br i1 %tmp1672, label %bb1678, label %bb1553
+
+bb1678:		; preds = %bb1669
+	ret %struct.LIST_NODE* null
+}