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; RUN: opt < %s -loop-vectorize -force-vector-unroll=1 -force-vector-width=4 -dce -instcombine -S | FileCheck %s
target 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"
target triple = "x86_64-unknown-linux-gnu"
; A tricky loop:
;
; void loop(int *a, int *b) {
; for (int i = 0; i < 512; ++i) {
; a[a[i]] = b[i];
; a[i] = b[i+1];
; }
;}
;CHECK-LABEL: @loop(
;CHECK-NOT: <4 x i32>
define void @loop(i32* nocapture %a, i32* nocapture %b) nounwind uwtable {
entry:
br label %for.body
for.body: ; preds = %for.body, %entry
%indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ]
%arrayidx = getelementptr inbounds i32* %b, i64 %indvars.iv
%0 = load i32* %arrayidx, align 4
%arrayidx2 = getelementptr inbounds i32* %a, i64 %indvars.iv
%1 = load i32* %arrayidx2, align 4
%idxprom3 = sext i32 %1 to i64
%arrayidx4 = getelementptr inbounds i32* %a, i64 %idxprom3
store i32 %0, i32* %arrayidx4, align 4
%indvars.iv.next = add i64 %indvars.iv, 1
%arrayidx6 = getelementptr inbounds i32* %b, i64 %indvars.iv.next
%2 = load i32* %arrayidx6, align 4
store i32 %2, i32* %arrayidx2, align 4
%lftr.wideiv = trunc i64 %indvars.iv.next to i32
%exitcond = icmp eq i32 %lftr.wideiv, 512
br i1 %exitcond, label %for.end, label %for.body
for.end: ; preds = %for.body
ret void
}
; The same loop with parallel loop metadata added to the loop branch
; and the memory instructions.
;CHECK-LABEL: @parallel_loop(
;CHECK: <4 x i32>
define void @parallel_loop(i32* nocapture %a, i32* nocapture %b) nounwind uwtable {
entry:
br label %for.body
for.body: ; preds = %for.body, %entry
%indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ]
%arrayidx = getelementptr inbounds i32* %b, i64 %indvars.iv
%0 = load i32* %arrayidx, align 4, !llvm.mem.parallel_loop_access !3
%arrayidx2 = getelementptr inbounds i32* %a, i64 %indvars.iv
%1 = load i32* %arrayidx2, align 4, !llvm.mem.parallel_loop_access !3
%idxprom3 = sext i32 %1 to i64
%arrayidx4 = getelementptr inbounds i32* %a, i64 %idxprom3
; This store might have originated from inlining a function with a parallel
; loop. Refers to a list with the "original loop reference" (!4) also included.
store i32 %0, i32* %arrayidx4, align 4, !llvm.mem.parallel_loop_access !5
%indvars.iv.next = add i64 %indvars.iv, 1
%arrayidx6 = getelementptr inbounds i32* %b, i64 %indvars.iv.next
%2 = load i32* %arrayidx6, align 4, !llvm.mem.parallel_loop_access !3
store i32 %2, i32* %arrayidx2, align 4, !llvm.mem.parallel_loop_access !3
%lftr.wideiv = trunc i64 %indvars.iv.next to i32
%exitcond = icmp eq i32 %lftr.wideiv, 512
br i1 %exitcond, label %for.end, label %for.body, !llvm.loop !3
for.end: ; preds = %for.body
ret void
}
; The same loop with an illegal parallel loop metadata: the memory
; accesses refer to a different loop's identifier.
;CHECK-LABEL: @mixed_metadata(
;CHECK-NOT: <4 x i32>
define void @mixed_metadata(i32* nocapture %a, i32* nocapture %b) nounwind uwtable {
entry:
br label %for.body
for.body: ; preds = %for.body, %entry
%indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ]
%arrayidx = getelementptr inbounds i32* %b, i64 %indvars.iv
%0 = load i32* %arrayidx, align 4, !llvm.mem.parallel_loop_access !6
%arrayidx2 = getelementptr inbounds i32* %a, i64 %indvars.iv
%1 = load i32* %arrayidx2, align 4, !llvm.mem.parallel_loop_access !6
%idxprom3 = sext i32 %1 to i64
%arrayidx4 = getelementptr inbounds i32* %a, i64 %idxprom3
; This refers to the loop marked with !7 which we are not in at the moment.
; It should prevent detecting as a parallel loop.
store i32 %0, i32* %arrayidx4, align 4, !llvm.mem.parallel_loop_access !7
%indvars.iv.next = add i64 %indvars.iv, 1
%arrayidx6 = getelementptr inbounds i32* %b, i64 %indvars.iv.next
%2 = load i32* %arrayidx6, align 4, !llvm.mem.parallel_loop_access !6
store i32 %2, i32* %arrayidx2, align 4, !llvm.mem.parallel_loop_access !6
%lftr.wideiv = trunc i64 %indvars.iv.next to i32
%exitcond = icmp eq i32 %lftr.wideiv, 512
br i1 %exitcond, label %for.end, label %for.body, !llvm.loop !6
for.end: ; preds = %for.body
ret void
}
!3 = metadata !{metadata !3}
!4 = metadata !{metadata !4}
!5 = metadata !{metadata !3, metadata !4}
!6 = metadata !{metadata !6}
!7 = metadata !{metadata !7}
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