[DAGCombiner] Fix for oss-fuzz bug

llvm-svn: 330178
diff --git a/llvm/test/CodeGen/Generic/dag-combine-ossfuzz-crash.ll b/llvm/test/CodeGen/Generic/dag-combine-ossfuzz-crash.ll
new file mode 100644
index 0000000..650d4b4
--- /dev/null
+++ b/llvm/test/CodeGen/Generic/dag-combine-ossfuzz-crash.ll
@@ -0,0 +1,53 @@
+; RUN: llc < %s
+
+; llc built with address sanitizer crashes because of a dangling node pointer
+; oss-fuzz -  DAGCombiner::useDivRem (5011)
+
+define void @f() {
+BB:
+  %A19 = alloca i1**
+  %C18 = icmp ugt i1 true, false
+  %L13 = load i8, i8* undef
+  %L10 = load i8, i8* undef
+  %B12 = and i8 %L13, %L10
+  %B35 = and i8 %B12, %L10
+  %L2 = load i66*, i66** undef
+  %L23 = load i66, i66* %L2
+  %B38 = urem i8 %B35, %B12
+  %B9 = ashr i66 %L23, %L23
+  %C11 = icmp sge i8 %B38, %B35
+  %A4 = alloca i66
+  %G4 = getelementptr i66, i66* %A4, i1 true
+  %L6 = load i66, i66* %G4
+  %B21 = urem i1 %C11, true
+  %B1 = mul i66 %B9, %L23
+  %B5 = udiv i8 %L10, %L13
+  %B22 = udiv i66 %B9, %B1
+  %C29 = icmp ult i32 -1, 0
+  store i1* undef, i1** undef
+  store i1 %C29, i1* undef
+  br label %BB1
+
+BB1:                                              ; preds = %BB
+  %G8 = getelementptr i66, i66* undef, i16 32767
+  %G43 = getelementptr i66, i66* undef, i66 -1
+  %L20 = load i1, i1* undef
+  %B7 = and i66 %L6, %L6
+  %B30 = sdiv i66 -36893488147419103232, -1
+  %B16 = urem i66 %B22, %L6
+  %G47 = getelementptr i66, i66* %G8, i66 %B16
+  store i66 %B7, i66* %G47
+  store i8 %B5, i8* undef
+  %C5 = icmp ult i1 %C18, %L20
+  store i66 %B30, i66* %G47
+  store i1** undef, i1*** %A19
+  store i1 %C5, i1* undef
+  store i1 %C11, i1* undef
+  store i66* %G43, i66** undef
+  store i1 %B21, i1* undef
+  %G59 = getelementptr i1, i1* undef, i1 false
+  %G61 = getelementptr i66, i66* %G8, i1 %L20
+  store i1 %L20, i1* %G59
+  store i66* %G61, i66** undef
+  ret void
+}