1 files changed, 37 insertions, 0 deletions
diff --git a/llvm/test/Transforms/CodeGenPrepare/ARM/bitreverse-recognize.ll b/llvm/test/Transforms/CodeGenPrepare/ARM/bitreverse-recognize.ll
new file mode 100644
index 00000000000..f5644e4ad31
--- /dev/null
+++ b/llvm/test/Transforms/CodeGenPrepare/ARM/bitreverse-recognize.ll
@@ -0,0 +1,37 @@
+; RUN: opt -S -loop-unroll -codegenprepare < %s | FileCheck %s
+
+target datalayout = "e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64"
+target triple = "armv7--linux-gnueabihf"
+
+; CHECK-LABEL: @f
+define i32 @f(i32 %a) #0 {
+; CHECK: call i32 @llvm.bitreverse.i32
+entry:
+  br label %for.body
+
+for.cond.cleanup:                                 ; preds = %for.body
+  ret i32 %or
+
+for.body:                                         ; preds = %for.body, %entry
+  %i.08 = phi i32 [ 0, %entry ], [ %inc, %for.body ]
+  %b.07 = phi i32 [ 0, %entry ], [ %or, %for.body ]
+  %shr = lshr i32 %a, %i.08
+  %and = and i32 %shr, 1
+  %sub = sub nuw nsw i32 31, %i.08
+  %shl = shl i32 %and, %sub
+  %or = or i32 %shl, %b.07
+  %inc = add nuw nsw i32 %i.08, 1
+  %exitcond = icmp eq i32 %inc, 32
+  br i1 %exitcond, label %for.cond.cleanup, label %for.body, !llvm.loop !3
+}
+
+attributes #0 = { norecurse nounwind readnone "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="cortex-a8" "target-features"="+dsp,+neon,+vfp3" "unsafe-fp-math"="false" "use-soft-float"="false" }
+
+!llvm.module.flags = !{!0, !1}
+!llvm.ident = !{!2}
+
+!0 = !{i32 1, !"wchar_size", i32 4}
+!1 = !{i32 1, !"min_enum_size", i32 4}
+!2 = !{!"clang version 3.8.0"}
+!3 = distinct !{!3, !4}
+!4 = !{!"llvm.loop.unroll.full"}