-; RUN: opt < %s -loop-vectorize -dce -instcombine -licm -S | FileCheck %s
+; 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-apple-macosx10.8.0"
; for (i=0; i<n; i++){
; a[i] += i;
; }
-;CHECK: @inc
+;CHECK-LABEL: @inc(
;CHECK: load <4 x i32>
-;CHECK: add <4 x i32>
+;CHECK: add nsw <4 x i32>
;CHECK: store <4 x i32>
;CHECK: ret void
define void @inc(i32 %n) nounwind uwtable noinline ssp {
._crit_edge: ; preds = %.lr.ph, %0
ret void
}
+
+; Can't vectorize this loop because the access to A[X] is non linear.
+;
+; for (i = 0; i < n; ++i) {
+; A[B[i]]++;
+;
+;CHECK-LABEL: @histogram(
+;CHECK-NOT: <4 x i32>
+;CHECK: ret i32
+define i32 @histogram(i32* nocapture noalias %A, i32* nocapture noalias %B, i32 %n) nounwind uwtable ssp {
+entry:
+ %cmp6 = icmp sgt i32 %n, 0
+ br i1 %cmp6, label %for.body, label %for.end
+
+for.body: ; preds = %entry, %for.body
+ %indvars.iv = phi i64 [ %indvars.iv.next, %for.body ], [ 0, %entry ]
+ %arrayidx = getelementptr inbounds i32* %B, i64 %indvars.iv
+ %0 = load i32* %arrayidx, align 4
+ %idxprom1 = sext i32 %0 to i64
+ %arrayidx2 = getelementptr inbounds i32* %A, i64 %idxprom1
+ %1 = load i32* %arrayidx2, align 4
+ %inc = add nsw i32 %1, 1
+ store i32 %inc, i32* %arrayidx2, align 4
+ %indvars.iv.next = add i64 %indvars.iv, 1
+ %lftr.wideiv = trunc i64 %indvars.iv.next to i32
+ %exitcond = icmp eq i32 %lftr.wideiv, %n
+ br i1 %exitcond, label %for.end, label %for.body
+
+for.end: ; preds = %for.body, %entry
+ ret i32 0
+}