1 files changed, 65 insertions, 0 deletions
diff --git a/test/Transforms/LoopDistribute/symbolic-stride.ll b/test/Transforms/LoopDistribute/symbolic-stride.ll
new file mode 100644
index 0000000000000..73d3d19c5dd4a
--- /dev/null
+++ b/test/Transforms/LoopDistribute/symbolic-stride.ll
@@ -0,0 +1,65 @@
+; RUN: opt -basicaa -loop-distribute -S < %s | \
+; RUN:     FileCheck %s --check-prefix=ALL --check-prefix=STRIDE_SPEC
+
+; RUN: opt -basicaa -loop-distribute -S -enable-mem-access-versioning=0 < %s | \
+; RUN:     FileCheck %s --check-prefix=ALL --check-prefix=NO_STRIDE_SPEC
+
+; If we don't speculate stride for 1 we can't distribute along the line
+; because we could have a backward dependence:
+;
+;   for (i = 0; i < n; i++) {
+;     A[i + 1] = A[i] * B[i];
+;     =======================
+;     C[i] = D[i] * A[stride * i];
+;   }
+
+target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-apple-macosx10.10.0"
+
+; ALL-LABEL: @f(
+define void @f(i32* noalias %a,
+               i32* noalias %b,
+               i32* noalias %c,
+               i32* noalias %d,
+               i64 %stride) {
+entry:
+  br label %for.body
+
+; STRIDE_SPEC: %ident.check = icmp ne i64 %stride, 1
+
+; STRIDE_SPEC: for.body.ldist1:
+; NO_STRIDE_SPEC-NOT: for.body.ldist1:
+
+for.body:                                         ; preds = %for.body, %entry
+  %ind = phi i64 [ 0, %entry ], [ %add, %for.body ]
+
+  %arrayidxA = getelementptr inbounds i32, i32* %a, i64 %ind
+  %loadA = load i32, i32* %arrayidxA, align 4
+
+  %arrayidxB = getelementptr inbounds i32, i32* %b, i64 %ind
+  %loadB = load i32, i32* %arrayidxB, align 4
+
+  %mulA = mul i32 %loadB, %loadA
+
+  %add = add nuw nsw i64 %ind, 1
+  %arrayidxA_plus_4 = getelementptr inbounds i32, i32* %a, i64 %add
+  store i32 %mulA, i32* %arrayidxA_plus_4, align 4
+
+  %arrayidxD = getelementptr inbounds i32, i32* %d, i64 %ind
+  %loadD = load i32, i32* %arrayidxD, align 4
+
+  %mul = mul i64 %ind, %stride
+  %arrayidxStridedA = getelementptr inbounds i32, i32* %a, i64 %mul
+  %loadStridedA = load i32, i32* %arrayidxStridedA, align 4
+
+  %mulC = mul i32 %loadD, %loadStridedA
+
+  %arrayidxC = getelementptr inbounds i32, i32* %c, i64 %ind
+  store i32 %mulC, i32* %arrayidxC, align 4
+
+  %exitcond = icmp eq i64 %add, 20
+  br i1 %exitcond, label %for.end, label %for.body
+
+for.end:                                          ; preds = %for.body
+  ret void
+}