From: Chris Lattner <sabre@nondot.org>
Date: Tue, 20 Jan 2009 01:15:41 +0000 (+0000)
Subject: another fix for PR3354
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=63bf29b5b1c741038d6d502d62721cac0d2760b4;p=oota-llvm.git

another fix for PR3354


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62561 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Transforms/Utils/SimplifyCFG.cpp b/lib/Transforms/Utils/SimplifyCFG.cpp
index 1a4f57320f7..d891eebf33c 100644
--- a/lib/Transforms/Utils/SimplifyCFG.cpp
+++ b/lib/Transforms/Utils/SimplifyCFG.cpp
@@ -1559,6 +1559,11 @@ static bool SimplifyCondBranchToCondBranch(BranchInst *PBI, BranchInst *BI) {
   // fold the conditions into logical ops and one cond br.
   if (&BB->front() != BI)
     return false;
+
+  
+  if (ConstantExpr *CE = dyn_cast<ConstantExpr>(BI->getCondition()))
+    if (CE->canTrap())
+      return false;
   
   int PBIOp, BIOp;
   if (PBI->getSuccessor(0) == BI->getSuccessor(0))
diff --git a/test/Transforms/SimplifyCFG/2009-01-19-UnconditionalTrappingConstantExpr.ll b/test/Transforms/SimplifyCFG/2009-01-19-UnconditionalTrappingConstantExpr.ll
index 0bc6bdb895b..1a6f485f662 100644
--- a/test/Transforms/SimplifyCFG/2009-01-19-UnconditionalTrappingConstantExpr.ll
+++ b/test/Transforms/SimplifyCFG/2009-01-19-UnconditionalTrappingConstantExpr.ll
@@ -1,4 +1,4 @@
-; RUN: llvm-as < %s | opt -simplifycfg | llvm-dis | grep {br i1 } | count 2
+; RUN: llvm-as < %s | opt -simplifycfg | llvm-dis | grep {br i1 } | count 4
 ; PR3354
 ; Do not merge bb1 into the entry block, it might trap.
 
@@ -18,3 +18,14 @@ bb6:
 	unwind
 }
 
+define i32 @test2(i32 %tmp21, i32 %tmp24, i1 %tmp34) {
+	br i1 %tmp34, label %bb5, label %bb6
+
+bb5:		; preds = %bb4
+	br i1 icmp sgt (i32 sdiv (i32 32767, i32 0), i32 0), label %bb6, label %bb7
+bb6:
+	ret i32 42
+bb7:
+	unwind
+}
+