git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@185187 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 45 insertions, 0 deletions

diff --git a/lib/Analysis/DependenceAnalysis.cpp b/lib/Analysis/DependenceAnalysis.cpp
index cbc71bd..450dcbc 100644
--- a/lib/Analysis/DependenceAnalysis.cpp
+++ b/lib/Analysis/DependenceAnalysis.cpp
@@ -2951,6 +2951,11 @@ const SCEV *DependenceAnalysis::addToCoefficient(const SCEV *Expr,
                              AddRec->getLoop(),
                              AddRec->getNoWrapFlags());
   }
+  if (SE->isLoopInvariant(AddRec, TargetLoop))
+    return SE->getAddRecExpr(AddRec,
+			     Value,
+			     TargetLoop,
+			     SCEV::FlagAnyWrap);
   return SE->getAddRecExpr(addToCoefficient(AddRec->getStart(),
                                             TargetLoop, Value),
                            AddRec->getStepRecurrence(*SE),
diff --git a/test/Analysis/DependenceAnalysis/Invariant.ll b/test/Analysis/DependenceAnalysis/Invariant.ll
new file mode 100644
index 0000000..202d8e2
--- /dev/null
+++ b/test/Analysis/DependenceAnalysis/Invariant.ll
@@ -0,0 +1,40 @@
+; RUN: opt < %s -analyze -basicaa -da | FileCheck %s
+
+; Test for a bug, which caused an assert when an invalid
+; SCEVAddRecExpr is created in addToCoefficient.
+
+; CHECK: da analyze - consistent input [S 0]!
+; CHECK: da analyze - input [* 0|<]!
+; CHECK: da analyze - none!
+
+define float @foo(float %g, [40 x float]* %rr) nounwind {
+entry:
+  br label %for.cond1.preheader
+
+for.cond1.preheader:
+  %i.04 = phi i32 [ 0, %entry ], [ %add10, %for.inc9 ]
+  %res.03 = phi float [ 0.000000e+00, %entry ], [ %add.res.1, %for.inc9 ]
+  br label %for.body3
+
+for.body3:
+  %j.02 = phi i32 [ 0, %for.cond1.preheader ], [ %add8, %for.body3 ]
+  %res.11 = phi float [ %res.03, %for.cond1.preheader ], [ %add.res.1, %for.body3 ]
+  %arrayidx4 = getelementptr inbounds [40 x float]* %rr, i32 %j.02, i32 %j.02
+  %0 = load float* %arrayidx4, align 4
+  %arrayidx6 = getelementptr inbounds [40 x float]* %rr, i32 %i.04, i32 %j.02
+  %1 = load float* %arrayidx6, align 4
+  %add = fadd float %0, %1
+  %cmp7 = fcmp ogt float %add, %g
+  %add.res.1 = select i1 %cmp7, float %add, float %res.11
+  %add8 = add nsw i32 %j.02, 5
+  %cmp2 = icmp slt i32 %add8, 40
+  br i1 %cmp2, label %for.body3, label %for.inc9
+
+for.inc9:
+  %add10 = add nsw i32 %i.04, 5
+  %cmp = icmp slt i32 %add10, 40
+  br i1 %cmp, label %for.cond1.preheader, label %for.end11
+
+for.end11:
+  ret float %add.res.1
+}