; 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] = b[i*M+j] * 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(i32* nocapture %a, i32* 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, i32* %b, i64 %2 %3 = load i32, i32* %arrayidx, align 4, !tbaa !2 %mul8 = mul nsw i32 %3, %3 %arrayidx12 = getelementptr inbounds i32, i32* %a, i64 %2 store i32 %mul8, i32* %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(i32* nocapture %a, i32* 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, i32* %b, i64 %2 %3 = load i32, i32* %arrayidx, align 4, !tbaa !2 %mul8 = mul nsw i32 %3, %3 %arrayidx12 = getelementptr inbounds i32, i32* %a, i64 %2 store i32 %mul8, i32* %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(i32* nocapture %a, i32* 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, i32* %b, i64 %2 %3 = load i32, i32* %arrayidx, align 4, !tbaa !2 %mul8 = mul nsw i32 %3, %3 %arrayidx12 = getelementptr inbounds i32, i32* %a, i64 %2 store i32 %mul8, i32* %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}