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; RUN: opt < %s -passes=loop-vectorize -enable-vplan-native-path -pass-remarks-analysis=loop-vectorize -debug-only=loop-vectorize -S 2>&1 | FileCheck %s
; REQUIRES: asserts
; Verify that LV bails out on explicit vectorization outer loops that contain
; divergent inner loops.
; Root C/C++ source code for all the test cases
; void foo(int *a, int *b, int N, int M)
; {
; int i, j;
; #pragma clang loop vectorize(enable) vectorize_width(8)
; for (i = 0; i < N; i++) {
; // Tested inner loop. It will be replaced per test.
; for (j = 0; j < M; j++) {
; a[i*M+j] = bptr b[i*M+j];
; }
; }
; }
; Case 1 (for (j = i; j < M; j++)): Inner loop with divergent IV start.
; CHECK-LABEL: iv_start
; CHECK: LV: Not vectorizing: Outer loop contains divergent loops.
; CHECK: LV: Not vectorizing: Unsupported outer loop.
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
define void @iv_start(ptr nocapture %a, ptr nocapture readonly %b, i32 %N, i32 %M) local_unnamed_addr {
entry:
%cmp33 = icmp sgt i32 %N, 0
br i1 %cmp33, label %outer.ph, label %for.end15
outer.ph: ; preds = %entry
%0 = sext i32 %M to i64
%wide.trip.count = zext i32 %M to i64
%wide.trip.count41 = zext i32 %N to i64
br label %outer.body
outer.body: ; preds = %outer.inc, %outer.ph
%indvars.iv38 = phi i64 [ 0, %outer.ph ], [ %indvars.iv.next39, %outer.inc ]
%cmp231 = icmp slt i64 %indvars.iv38, %0
br i1 %cmp231, label %inner.ph, label %outer.inc
inner.ph: ; preds = %outer.body
%1 = mul nsw i64 %indvars.iv38, %0
br label %inner.body
inner.body: ; preds = %inner.body, %inner.ph
%indvars.iv35 = phi i64 [ %indvars.iv38, %inner.ph ], [ %indvars.iv.next36, %inner.body ]
%2 = add nsw i64 %indvars.iv35, %1
%arrayidx = getelementptr inbounds i32, ptr %b, i64 %2
%3 = load i32, ptr %arrayidx, align 4, !tbaa !2
%mul8 = mul nsw i32 %3, %3
%arrayidx12 = getelementptr inbounds i32, ptr %a, i64 %2
store i32 %mul8, ptr %arrayidx12, align 4, !tbaa !2
%indvars.iv.next36 = add nuw nsw i64 %indvars.iv35, 1
%exitcond = icmp eq i64 %indvars.iv.next36, %wide.trip.count
br i1 %exitcond, label %outer.inc, label %inner.body
outer.inc: ; preds = %inner.body, %outer.body
%indvars.iv.next39 = add nuw nsw i64 %indvars.iv38, 1
%exitcond42 = icmp eq i64 %indvars.iv.next39, %wide.trip.count41
br i1 %exitcond42, label %for.end15, label %outer.body, !llvm.loop !6
for.end15: ; preds = %outer.inc, %entry
ret void
}
; Case 2 (for (j = 0; j < i; j++)): Inner loop with divergent upper-bound.
; CHECK-LABEL: loop_ub
; CHECK: LV: Not vectorizing: Outer loop contains divergent loops.
; CHECK: LV: Not vectorizing: Unsupported outer loop.
define void @loop_ub(ptr nocapture %a, ptr nocapture readonly %b, i32 %N, i32 %M) local_unnamed_addr {
entry:
%cmp32 = icmp sgt i32 %N, 0
br i1 %cmp32, label %outer.ph, label %for.end15
outer.ph: ; preds = %entry
%0 = sext i32 %M to i64
%wide.trip.count41 = zext i32 %N to i64
br label %outer.body
outer.body: ; preds = %outer.inc, %outer.ph
%indvars.iv38 = phi i64 [ 0, %outer.ph ], [ %indvars.iv.next39, %outer.inc ]
%cmp230 = icmp eq i64 %indvars.iv38, 0
br i1 %cmp230, label %outer.inc, label %inner.ph
inner.ph: ; preds = %outer.body
%1 = mul nsw i64 %indvars.iv38, %0
br label %inner.body
inner.body: ; preds = %inner.body, %inner.ph
%indvars.iv = phi i64 [ 0, %inner.ph ], [ %indvars.iv.next, %inner.body ]
%2 = add nsw i64 %indvars.iv, %1
%arrayidx = getelementptr inbounds i32, ptr %b, i64 %2
%3 = load i32, ptr %arrayidx, align 4, !tbaa !2
%mul8 = mul nsw i32 %3, %3
%arrayidx12 = getelementptr inbounds i32, ptr %a, i64 %2
store i32 %mul8, ptr %arrayidx12, align 4, !tbaa !2
%indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
%exitcond = icmp eq i64 %indvars.iv.next, %indvars.iv38
br i1 %exitcond, label %outer.inc, label %inner.body
outer.inc: ; preds = %inner.body, %outer.body
%indvars.iv.next39 = add nuw nsw i64 %indvars.iv38, 1
%exitcond42 = icmp eq i64 %indvars.iv.next39, %wide.trip.count41
br i1 %exitcond42, label %for.end15, label %outer.body, !llvm.loop !6
for.end15: ; preds = %outer.inc, %entry
ret void
}
; Case 3 (for (j = 0; j < M; j+=i)): Inner loop with divergent step.
; CHECK-LABEL: iv_step
; CHECK: LV: Not vectorizing: Outer loop contains divergent loops.
; CHECK: LV: Not vectorizing: Unsupported outer loop.
define void @iv_step(ptr nocapture %a, ptr nocapture readonly %b, i32 %N, i32 %M) local_unnamed_addr {
entry:
%cmp33 = icmp sgt i32 %N, 0
br i1 %cmp33, label %outer.ph, label %for.end15
outer.ph: ; preds = %entry
%cmp231 = icmp sgt i32 %M, 0
%0 = sext i32 %M to i64
%wide.trip.count = zext i32 %N to i64
br label %outer.body
outer.body: ; preds = %for.inc14, %outer.ph
%indvars.iv39 = phi i64 [ 0, %outer.ph ], [ %indvars.iv.next40, %for.inc14 ]
br i1 %cmp231, label %inner.ph, label %for.inc14
inner.ph: ; preds = %outer.body
%1 = mul nsw i64 %indvars.iv39, %0
br label %inner.body
inner.body: ; preds = %inner.ph, %inner.body
%indvars.iv36 = phi i64 [ 0, %inner.ph ], [ %indvars.iv.next37, %inner.body ]
%2 = add nsw i64 %indvars.iv36, %1
%arrayidx = getelementptr inbounds i32, ptr %b, i64 %2
%3 = load i32, ptr %arrayidx, align 4, !tbaa !2
%mul8 = mul nsw i32 %3, %3
%arrayidx12 = getelementptr inbounds i32, ptr %a, i64 %2
store i32 %mul8, ptr %arrayidx12, align 4, !tbaa !2
%indvars.iv.next37 = add nuw nsw i64 %indvars.iv36, %indvars.iv39
%cmp2 = icmp slt i64 %indvars.iv.next37, %0
br i1 %cmp2, label %inner.body, label %for.inc14
for.inc14: ; preds = %inner.body, %outer.body
%indvars.iv.next40 = add nuw nsw i64 %indvars.iv39, 1
%exitcond = icmp eq i64 %indvars.iv.next40, %wide.trip.count
br i1 %exitcond, label %for.end15, label %outer.body, !llvm.loop !6
for.end15: ; preds = %for.inc14, %entry
ret void
}
!llvm.module.flags = !{!0}
!llvm.ident = !{!1}
!0 = !{i32 1, !"wchar_size", i32 4}
!1 = !{!"clang version 6.0.0"}
!2 = !{!3, !3, i64 0}
!3 = !{!"int", !4, i64 0}
!4 = !{!"omnipotent char", !5, i64 0}
!5 = !{!"Simple C/C++ TBAA"}
!6 = distinct !{!6, !7, !8}
!7 = !{!"llvm.loop.vectorize.width", i32 8}
!8 = !{!"llvm.loop.vectorize.enable", i1 true}
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