1 files changed, 53 insertions, 0 deletions
diff --git a/llvm/test/Transforms/LoopVectorize/AArch64/predication_costs.ll b/llvm/test/Transforms/LoopVectorize/AArch64/predication_costs.ll
new file mode 100644
index 00000000000..150073aa2ab
--- /dev/null
+++ b/llvm/test/Transforms/LoopVectorize/AArch64/predication_costs.ll
@@ -0,0 +1,53 @@
+; REQUIRES: asserts
+; RUN: opt < %s -force-vector-width=2 -loop-vectorize -debug-only=loop-vectorize -disable-output 2>&1 | FileCheck %s
+
+target datalayout = "e-m:e-i64:64-i128:128-n32:64-S128"
+target triple = "aarch64--linux-gnu"
+
+; Check predication-related cost calculations, including scalarization overhead
+; and block probability scaling. Note that the functionality being tested is
+; not specific to AArch64. We specify a target to get actual values for the
+; instruction costs.
+
+; CHECK-LABEL: predicated_udiv
+;
+; This test checks that we correctly compute the cost of the predicated udiv
+; instruction. If we assume the block probability is 50%, we compute the cost
+; as:
+;
+; Cost for vector lane zero:
+;   (udiv(1) + 2 * extractelement(0) + insertelement(0)) / 2 = 0
+; Cost for vector lane one:
+;   (udiv(1) + 2 * extractelement(3) + insertelement(3)) / 2 = 5
+;
+; CHECK: Found an estimated cost of 5 for VF 2 For instruction: %tmp4 = udiv i32 %tmp2, %tmp3
+; CHECK: Scalarizing and predicating: %tmp4 = udiv i32 %tmp2, %tmp3
+;
+define i32 @predicated_udiv(i32* %a, i32* %b, i1 %c, i64 %n) {
+entry:
+  br label %for.body
+
+for.body:
+  %i = phi i64 [ 0, %entry ], [ %i.next, %for.inc ]
+  %r = phi i32 [ 0, %entry ], [ %tmp6, %for.inc ]
+  %tmp0 = getelementptr inbounds i32, i32* %a, i64 %i
+  %tmp1 = getelementptr inbounds i32, i32* %b, i64 %i
+  %tmp2 = load i32, i32* %tmp0, align 4
+  %tmp3 = load i32, i32* %tmp1, align 4
+  br i1 %c, label %if.then, label %for.inc
+
+if.then:
+  %tmp4 = udiv i32 %tmp2, %tmp3
+  br label %for.inc
+
+for.inc:
+  %tmp5 = phi i32 [ %tmp3, %for.body ], [ %tmp4, %if.then]
+  %tmp6 = add i32 %r, %tmp5
+  %i.next = add nuw nsw i64 %i, 1
+  %cond = icmp slt i64 %i.next, %n
+  br i1 %cond, label %for.body, label %for.end
+
+for.end:
+  %tmp7 = phi i32 [ %tmp6, %for.inc ]
+  ret i32 %tmp7
+}