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 1a4f57320f79bc406bda8c6108bacdf2f811596b..d891eebf33c331e848ae9fe16b26c894e013a1c9 100644 (file)
--- 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 0bc6bdb895b0602b5ded0c9098d17abdf610abcc..1a6f485f6621e8e2bed32e790bf432dcbd320506 100644 (file)
--- 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
+}
+