From: Devang Patel <dpatel@apple.com>
Date: Thu, 18 Sep 2008 23:45:14 +0000 (+0000)
Subject: splitLoop does not handle split condition EQ.
X-Git-Url: http://plrg.eecs.uci.edu/git/?a=commitdiff_plain;h=4fe0fe8b493437e91f8510b81462ff39f0d889ca;p=oota-llvm.git

splitLoop does not handle split condition EQ.
Fixes PR 2805


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56321 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Transforms/Scalar/LoopIndexSplit.cpp b/lib/Transforms/Scalar/LoopIndexSplit.cpp
index 8cafe7424d0..085223cd814 100644
--- a/lib/Transforms/Scalar/LoopIndexSplit.cpp
+++ b/lib/Transforms/Scalar/LoopIndexSplit.cpp
@@ -1430,6 +1430,12 @@ bool LoopIndexSplit::splitLoop(SplitInfo &SD) {
   if (!safeSplitCondition(SD))
     return false;
 
+  // If split condition EQ is not handled.
+  if (ICmpInst *ICMP = dyn_cast<ICmpInst>(SD.SplitCondition)) {
+    if (ICMP->getPredicate() == ICmpInst::ICMP_EQ)
+      return false;
+  }
+  
   BasicBlock *SplitCondBlock = SD.SplitCondition->getParent();
   
   // Unable to handle triangle loops at the moment.
diff --git a/test/Transforms/LoopIndexSplit/2008-09-20-Crash.ll b/test/Transforms/LoopIndexSplit/2008-09-20-Crash.ll
new file mode 100644
index 00000000000..f66edcd062e
--- /dev/null
+++ b/test/Transforms/LoopIndexSplit/2008-09-20-Crash.ll
@@ -0,0 +1,38 @@
+; RUN: llvm-as < %s | opt -loop-index-split -disable-output
+; PR 2805
+@g_330 = common global i32 0		; <i32*> [#uses=1]
+
+define i32 @func_45(i32 %p_47) nounwind {
+entry:
+	br label %bb
+
+bb:		; preds = %bb3, %entry
+	%p_47_addr.0.reg2mem.0 = phi i32 [ 0, %entry ], [ %2, %bb3 ]		; <i32> [#uses=2]
+	%0 = icmp eq i32 %p_47_addr.0.reg2mem.0, 0		; <i1> [#uses=1]
+	br i1 %0, label %bb2, label %bb1
+
+bb1:		; preds = %bb
+	%1 = tail call i32 (...)* @func_70( i32 1 ) nounwind		; <i32> [#uses=0]
+	br label %bb3
+
+bb2:		; preds = %bb
+	store i32 1, i32* @g_330, align 4
+	br label %bb3
+
+bb3:		; preds = %bb2, %bb1
+	%2 = add i32 %p_47_addr.0.reg2mem.0, 1		; <i32> [#uses=3]
+	%3 = icmp ult i32 %2, 22		; <i1> [#uses=1]
+	br i1 %3, label %bb, label %bb6
+
+bb6:		; preds = %bb3
+	%.lcssa = phi i32 [ %2, %bb3 ]		; <i32> [#uses=1]
+	%4 = tail call i32 (...)* @func_95( i32 %.lcssa ) nounwind		; <i32> [#uses=1]
+	%5 = tail call i32 (...)* @func_56( i32 %4 ) nounwind		; <i32> [#uses=0]
+	ret i32 undef
+}
+
+declare i32 @func_70(...)
+
+declare i32 @func_95(...)
+
+declare i32 @func_56(...)