1 files changed, 46 insertions, 0 deletions
diff --git a/llvm/test/Transforms/LoopVectorize/X86/already-vectorized.ll b/llvm/test/Transforms/LoopVectorize/X86/already-vectorized.ll
new file mode 100644
index 00000000000..60dd07698a3
--- /dev/null
+++ b/llvm/test/Transforms/LoopVectorize/X86/already-vectorized.ll
@@ -0,0 +1,46 @@
+; RUN: opt < %s -disable-loop-unrolling -debug-only=loop-vectorize -O3 -S 2>&1 | FileCheck %s
+; REQUIRES: asserts
+; We want to make sure that we don't even try to vectorize loops again
+; The vectorizer used to mark the un-vectorized loop only as already vectorized
+; thus, trying to vectorize the vectorized loop again
+
+target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+@a = external global [255 x i32]
+
+; Function Attrs: nounwind readonly uwtable
+define i32 @vect() {
+; CHECK: LV: Checking a loop in "vect"
+entry:
+  br label %for.body
+
+for.body:                                         ; preds = %for.body, %entry
+; We need to make sure we did vectorize the loop
+; CHECK: LV: Found a loop: for.body
+; CHECK: LV: We can vectorize this loop!
+  %indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ]
+  %red.05 = phi i32 [ 0, %entry ], [ %add, %for.body ]
+  %arrayidx = getelementptr inbounds [255 x i32], [255 x i32]* @a, i64 0, i64 %indvars.iv
+  %0 = load i32, i32* %arrayidx, align 4
+  %add = add nsw i32 %0, %red.05
+  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
+  %exitcond = icmp eq i64 %indvars.iv.next, 255
+  br i1 %exitcond, label %for.end, label %for.body
+
+; If it did, we have two loops:
+; CHECK: vector.body:
+; CHECK: br {{.*}} label %vector.body, !llvm.loop [[vect:![0-9]+]]
+; CHECK: for.body:
+; CHECK: br {{.*}} label %for.body, !llvm.loop [[scalar:![0-9]+]]
+
+for.end:                                          ; preds = %for.body
+  ret i32 %add
+}
+
+; Now, we check for the Hint metadata
+; CHECK: [[vect]] = distinct !{[[vect]], [[width:![0-9]+]]}
+; CHECK: [[width]] = !{!"llvm.loop.isvectorized", i32 1}
+; CHECK: [[scalar]] = distinct !{[[scalar]], [[runtime_unroll:![0-9]+]], [[width]]}
+; CHECK: [[runtime_unroll]] = !{!"llvm.loop.unroll.runtime.disable"}
+