1 files changed, 211 insertions, 0 deletions
diff --git a/llvm/test/Transforms/LoopVectorize/tripcount.ll b/llvm/test/Transforms/LoopVectorize/tripcount.ll
new file mode 100644
index 00000000000..56f8b3e83c7
--- /dev/null
+++ b/llvm/test/Transforms/LoopVectorize/tripcount.ll
@@ -0,0 +1,211 @@
+; This test verifies that the loop vectorizer will not vectorizes low trip count
+; loops that require runtime checks (Trip count is computed with profile info).
+; REQUIRES: asserts
+; RUN: opt < %s -loop-vectorize -loop-vectorize-with-block-frequency -S | FileCheck %s
+
+target datalayout = "E-m:e-p:32:32-i64:32-f64:32:64-a:0:32-n32-S128"
+
+@tab = common global [32 x i8] zeroinitializer, align 1
+
+define i32 @foo_low_trip_count1(i32 %bound) {
+; Simple loop with low tripcount. Should not be vectorized.
+
+; CHECK-LABEL: @foo_low_trip_count1(
+; CHECK-NOT: <{{[0-9]+}} x i8>
+
+entry:
+  br label %for.body
+
+for.body:                                         ; preds = %for.body, %entry
+  %i.08 = phi i32 [ 0, %entry ], [ %inc, %for.body ]
+  %arrayidx = getelementptr inbounds [32 x i8], [32 x i8]* @tab, i32 0, i32 %i.08
+  %0 = load i8, i8* %arrayidx, align 1
+  %cmp1 = icmp eq i8 %0, 0
+  %. = select i1 %cmp1, i8 2, i8 1
+  store i8 %., i8* %arrayidx, align 1
+  %inc = add nsw i32 %i.08, 1
+  %exitcond = icmp eq i32 %i.08, %bound
+  br i1 %exitcond, label %for.end, label %for.body, !prof !1
+
+for.end:                                          ; preds = %for.body
+  ret i32 0
+}
+
+define i32 @foo_low_trip_count2(i32 %bound) !prof !0 {
+; The loop has a same invocation count with the function, but has a low
+; trip_count per invocation and not worth to vectorize.
+
+; CHECK-LABEL: @foo_low_trip_count2(
+; CHECK-NOT: <{{[0-9]+}} x i8>
+
+entry:
+  br label %for.body
+
+for.body:                                         ; preds = %for.body, %entry
+  %i.08 = phi i32 [ 0, %entry ], [ %inc, %for.body ]
+  %arrayidx = getelementptr inbounds [32 x i8], [32 x i8]* @tab, i32 0, i32 %i.08
+  %0 = load i8, i8* %arrayidx, align 1
+  %cmp1 = icmp eq i8 %0, 0
+  %. = select i1 %cmp1, i8 2, i8 1
+  store i8 %., i8* %arrayidx, align 1
+  %inc = add nsw i32 %i.08, 1
+  %exitcond = icmp eq i32 %i.08, %bound
+  br i1 %exitcond, label %for.end, label %for.body, !prof !1
+
+for.end:                                          ; preds = %for.body
+  ret i32 0
+}
+
+define i32 @foo_low_trip_count3(i1 %cond, i32 %bound) !prof !0 {
+; The loop has low invocation count compare to the function invocation count,
+; but has a high trip count per invocation. Vectorize it.
+
+; CHECK-LABEL: @foo_low_trip_count3(
+; CHECK: vector.body:
+
+entry:
+  br i1 %cond, label %for.preheader, label %for.end, !prof !2
+
+for.preheader:
+  br label %for.body
+
+for.body:                                         ; preds = %for.body, %entry
+  %i.08 = phi i32 [ 0, %for.preheader ], [ %inc, %for.body ]
+  %arrayidx = getelementptr inbounds [32 x i8], [32 x i8]* @tab, i32 0, i32 %i.08
+  %0 = load i8, i8* %arrayidx, align 1
+  %cmp1 = icmp eq i8 %0, 0
+  %. = select i1 %cmp1, i8 2, i8 1
+  store i8 %., i8* %arrayidx, align 1
+  %inc = add nsw i32 %i.08, 1
+  %exitcond = icmp eq i32 %i.08, %bound
+  br i1 %exitcond, label %for.end, label %for.body, !prof !3
+
+for.end:                                          ; preds = %for.body
+  ret i32 0
+}
+
+define i32 @foo_low_trip_count_icmp_sgt(i32 %bound) {
+; Simple loop with low tripcount and inequality test for exit.
+; Should not be vectorized.
+
+; CHECK-LABEL: @foo_low_trip_count_icmp_sgt(
+; CHECK-NOT: <{{[0-9]+}} x i8>
+
+entry:
+  br label %for.body
+
+for.body:                                         ; preds = %for.body, %entry
+  %i.08 = phi i32 [ 0, %entry ], [ %inc, %for.body ]
+  %arrayidx = getelementptr inbounds [32 x i8], [32 x i8]* @tab, i32 0, i32 %i.08
+  %0 = load i8, i8* %arrayidx, align 1
+  %cmp1 = icmp eq i8 %0, 0
+  %. = select i1 %cmp1, i8 2, i8 1
+  store i8 %., i8* %arrayidx, align 1
+  %inc = add nsw i32 %i.08, 1
+  %exitcond = icmp sgt i32 %i.08, %bound
+  br i1 %exitcond, label %for.end, label %for.body, !prof !1
+
+for.end:                                          ; preds = %for.body
+  ret i32 0
+}
+
+define i32 @const_low_trip_count() {
+; Simple loop with constant, small trip count and no profiling info.
+
+; CHECK-LABEL: @const_low_trip_count
+; CHECK-NOT: <{{[0-9]+}} x i8>
+
+entry:
+  br label %for.body
+
+for.body:                                         ; preds = %for.body, %entry
+  %i.08 = phi i32 [ 0, %entry ], [ %inc, %for.body ]
+  %arrayidx = getelementptr inbounds [32 x i8], [32 x i8]* @tab, i32 0, i32 %i.08
+  %0 = load i8, i8* %arrayidx, align 1
+  %cmp1 = icmp eq i8 %0, 0
+  %. = select i1 %cmp1, i8 2, i8 1
+  store i8 %., i8* %arrayidx, align 1
+  %inc = add nsw i32 %i.08, 1
+  %exitcond = icmp slt i32 %i.08, 2
+  br i1 %exitcond, label %for.body, label %for.end
+
+for.end:                                          ; preds = %for.body
+  ret i32 0
+}
+
+define i32 @const_large_trip_count() {
+; Simple loop with constant large trip count and no profiling info.
+
+; CHECK-LABEL: @const_large_trip_count
+; CHECK: <{{[0-9]+}} x i8>
+
+entry:
+  br label %for.body
+
+for.body:                                         ; preds = %for.body, %entry
+  %i.08 = phi i32 [ 0, %entry ], [ %inc, %for.body ]
+  %arrayidx = getelementptr inbounds [32 x i8], [32 x i8]* @tab, i32 0, i32 %i.08
+  %0 = load i8, i8* %arrayidx, align 1
+  %cmp1 = icmp eq i8 %0, 0
+  %. = select i1 %cmp1, i8 2, i8 1
+  store i8 %., i8* %arrayidx, align 1
+  %inc = add nsw i32 %i.08, 1
+  %exitcond = icmp slt i32 %i.08, 1000
+  br i1 %exitcond, label %for.body, label %for.end
+
+for.end:                                          ; preds = %for.body
+  ret i32 0
+}
+
+define i32 @const_small_trip_count_step() {
+; Simple loop with static, small trip count and no profiling info.
+
+; CHECK-LABEL: @const_small_trip_count_step
+; CHECK-NOT: <{{[0-9]+}} x i8>
+
+entry:
+  br label %for.body
+
+for.body:                                         ; preds = %for.body, %entry
+  %i.08 = phi i32 [ 0, %entry ], [ %inc, %for.body ]
+  %arrayidx = getelementptr inbounds [32 x i8], [32 x i8]* @tab, i32 0, i32 %i.08
+  %0 = load i8, i8* %arrayidx, align 1
+  %cmp1 = icmp eq i8 %0, 0
+  %. = select i1 %cmp1, i8 2, i8 1
+  store i8 %., i8* %arrayidx, align 1
+  %inc = add nsw i32 %i.08, 5
+  %exitcond = icmp slt i32 %i.08, 10
+  br i1 %exitcond, label %for.body, label %for.end
+
+for.end:                                          ; preds = %for.body
+  ret i32 0
+}
+
+define i32 @const_trip_over_profile() {
+; constant trip count takes precedence over profile data
+
+; CHECK-LABEL: @const_trip_over_profile
+; CHECK: <{{[0-9]+}} x i8>
+
+entry:
+  br label %for.body
+
+for.body:                                         ; preds = %for.body, %entry
+  %i.08 = phi i32 [ 0, %entry ], [ %inc, %for.body ]
+  %arrayidx = getelementptr inbounds [32 x i8], [32 x i8]* @tab, i32 0, i32 %i.08
+  %0 = load i8, i8* %arrayidx, align 1
+  %cmp1 = icmp eq i8 %0, 0
+  %. = select i1 %cmp1, i8 2, i8 1
+  store i8 %., i8* %arrayidx, align 1
+  %inc = add nsw i32 %i.08, 1
+  %exitcond = icmp slt i32 %i.08, 1000
+  br i1 %exitcond, label %for.body, label %for.end, !prof !1
+
+for.end:                                          ; preds = %for.body
+  ret i32 0
+}
+
+!0 = !{!"function_entry_count", i64 100}
+!1 = !{!"branch_weights", i32 100, i32 0}
+!2 = !{!"branch_weights", i32 10, i32 90}
+!3 = !{!"branch_weights", i32 10, i32 10000}