1 files changed, 41 insertions, 0 deletions
diff --git a/test/CodeGen/AArch64/regress-wzr-allocatable.ll b/test/CodeGen/AArch64/regress-wzr-allocatable.ll
new file mode 100644
index 0000000000..a587d83bd8
--- /dev/null
+++ b/test/CodeGen/AArch64/regress-wzr-allocatable.ll
@@ -0,0 +1,41 @@
+; RUN: llc -verify-machineinstrs < %s -march=aarch64 -O0
+
+; When WZR wasn't marked as reserved, this function tried to allocate
+; it at O0 and then generated an internal fault (mostly incidentally)
+; when it discovered that it was already in use for a multiplication.
+
+; I'm not really convinced this is a good test since it could easily
+; stop testing what it does now with no-one any the wiser. However, I
+; can't think of a better way to force the allocator to use WZR
+; specifically.
+
+define void @test() nounwind {
+entry:
+  br label %for.cond
+
+for.cond:                                         ; preds = %for.body, %entry
+  br i1 undef, label %for.body, label %for.end
+
+for.body:                                         ; preds = %for.cond
+  br label %for.cond
+
+for.end:                                          ; preds = %for.cond
+  br label %for.cond6
+
+for.cond6:                                        ; preds = %for.body9, %for.end
+  br i1 undef, label %for.body9, label %while.cond30
+
+for.body9:                                        ; preds = %for.cond6
+  store i16 0, i16* undef, align 2
+  %0 = load i32* undef, align 4
+  %1 = load i32* undef, align 4
+  %mul15 = mul i32 %0, %1
+  %add16 = add i32 %mul15, 32768
+  %div = udiv i32 %add16, 65535
+  %add17 = add i32 %div, 1
+  store i32 %add17, i32* undef, align 4
+  br label %for.cond6
+
+while.cond30:                                     ; preds = %for.cond6
+  ret void
+}