; 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 -passes=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], ptr @tab, i32 0, i32 %i.08
%0 = load i8, ptr %arrayidx, align 1
%cmp1 = icmp eq i8 %0, 0
%. = select i1 %cmp1, i8 2, i8 1
store i8 %., ptr %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], ptr @tab, i32 0, i32 %i.08
%0 = load i8, ptr %arrayidx, align 1
%cmp1 = icmp eq i8 %0, 0
%. = select i1 %cmp1, i8 2, i8 1
store i8 %., ptr %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:vector\.body]]:
; CHECK: br i1 [[TMP9:%.*]], label [[MIDDLE_BLOCK:%.*]], label %[[VECTOR_BODY]], !prof [[LP3:\!.*]],
; CHECK: [[FOR_BODY:for\.body]]:
; CHECK: br i1 [[EXITCOND:%.*]], label [[FOR_END_LOOPEXIT:%.*]], label %[[FOR_BODY]], !prof [[LP6:\!.*]],
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], ptr @tab, i32 0, i32 %i.08
%0 = load i8, ptr %arrayidx, align 1
%cmp1 = icmp eq i8 %0, 0
%. = select i1 %cmp1, i8 2, i8 1
store i8 %., ptr %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], ptr @tab, i32 0, i32 %i.08
%0 = load i8, ptr %arrayidx, align 1
%cmp1 = icmp eq i8 %0, 0
%. = select i1 %cmp1, i8 2, i8 1
store i8 %., ptr %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], ptr @tab, i32 0, i32 %i.08
%0 = load i8, ptr %arrayidx, align 1
%cmp1 = icmp eq i8 %0, 0
%. = select i1 %cmp1, i8 2, i8 1
store i8 %., ptr %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], ptr @tab, i32 0, i32 %i.08
%0 = load i8, ptr %arrayidx, align 1
%cmp1 = icmp eq i8 %0, 0
%. = select i1 %cmp1, i8 2, i8 1
store i8 %., ptr %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], ptr @tab, i32 0, i32 %i.08
%0 = load i8, ptr %arrayidx, align 1
%cmp1 = icmp eq i8 %0, 0
%. = select i1 %cmp1, i8 2, i8 1
store i8 %., ptr %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], ptr @tab, i32 0, i32 %i.08
%0 = load i8, ptr %arrayidx, align 1
%cmp1 = icmp eq i8 %0, 0
%. = select i1 %cmp1, i8 2, i8 1
store i8 %., ptr %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
}
; CHECK: [[LP3]] = !{!"branch_weights", i32 10, i32 2490}
; CHECK: [[LP6]] = !{!"branch_weights", i32 10, i32 0}
; original loop has latchExitWeight=10 and backedgeTakenWeight=10,000,
; therefore estimatedBackedgeTakenCount=1,000 and estimatedTripCount=1,001.
; Vectorizing by 4 produces estimatedTripCounts of 1,001/4=250 and 1,001%4=1
; for vectorized and remainder loops, respectively, therefore their
; estimatedBackedgeTakenCounts are 249 and 0, and so the weights recorded with
; loop invocation weights of 10 are the above {10, 2490} and {10, 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}
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