xref: /llvm-project/llvm/test/Transforms/LoopVectorize/unsafe-vf-hint-remark.ll (revision b8dccb7d56c7e32b549c00a094d1b6ac32a01328)
1; REQUIRES: asserts
2; RUN: opt -passes=loop-vectorize -pass-remarks-analysis=loop-vectorize -debug-only=loop-vectorize -S < %s 2>&1 | FileCheck %s
3
4; Make sure the unsafe user specified vectorization factor is clamped.
5
6target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128"
7
8; void foo(int *a, int *b) {
9;   #pragma clang loop vectorize(enable) vectorize_width(4)
10;   for (int i=0; i < 1024; ++i) {
11;     a[i + 2] = a[i] + b[i];
12;   }
13; }
14
15; CHECK: LV: User VF=4 is unsafe, clamping to max safe VF=2.
16; CHECK: remark: <unknown>:0:0: User-specified vectorization factor 4 is unsafe, clamping to maximum safe vectorization factor 2
17; CHECK: remark: <unknown>:0:0: UserVF ignored because it may be larger than the maximal safe VF
18; CHECK-LABEL: @foo
19; CHECK: <2 x i32>
20define void @foo(ptr %a, ptr %b) {
21entry:
22  br label %loop.ph
23
24loop.ph:
25  br label %loop
26
27loop:
28  %iv = phi i64 [ 0, %loop.ph ], [ %iv.next, %loop ]
29  %arrayidx = getelementptr inbounds i32, ptr %a, i64 %iv
30  %0 = load i32, ptr %arrayidx, align 4
31  %arrayidx2 = getelementptr inbounds i32, ptr %b, i64 %iv
32  %1 = load i32, ptr %arrayidx2, align 4
33  %add = add nsw i32 %1, %0
34  %2 = add nuw nsw i64 %iv, 2
35  %arrayidx5 = getelementptr inbounds i32, ptr %a, i64 %2
36  store i32 %add, ptr %arrayidx5, align 4
37  %iv.next = add nuw nsw i64 %iv, 1
38  %exitcond.not = icmp eq i64 %iv.next, 1024
39  br i1 %exitcond.not, label %exit, label %loop, !llvm.loop !0
40
41exit:
42  ret void
43}
44
45!0 = !{!0, !1, !2}
46!1 = !{!"llvm.loop.vectorize.width", i32 4}
47!2 = !{!"llvm.loop.vectorize.enable", i1 true}
48