Imported Upstream version 5.18.0.205

Former-commit-id: 7f59f7e792705db773f1caecdaa823092f4e2927

external/llvm/test/Transforms/LoopVectorize/bsd_regex.ll

@@ -0,0 +1,38 @@
+; RUN: opt -S -loop-vectorize -dce -instcombine -force-vector-width=2 -force-vector-interleave=2 < %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"
+
+;PR 15830.
+
+;CHECK-LABEL: @foo(
+; When scalarizing stores we need to preserve the original order.
+; Make sure that we are extracting in the correct order (0101, and not 0011).
+;CHECK: extractelement <2 x i64> {{.*}}, i32 0
+;CHECK: extractelement <2 x i64> {{.*}}, i32 1
+;CHECK: extractelement <2 x i64> {{.*}}, i32 0
+;CHECK: extractelement <2 x i64> {{.*}}, i32 1
+;CHECK: store
+;CHECK: store
+;CHECK: store
+;CHECK: store
+;CHECK: ret
+
+define i32 @foo(i32* nocapture %A) {
+entry:
+  br label %for.body
+
+for.body:
+  %indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ]
+  %0 = shl nsw i64 %indvars.iv, 2
+  %arrayidx = getelementptr inbounds i32, i32* %A, i64 %0
+  store i32 4, i32* %arrayidx, 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, 10000
+  br i1 %exitcond, label %for.end, label %for.body
+
+for.end:
+  ret i32 undef
+}
+
+