1 files changed, 76 insertions, 0 deletions
diff --git a/test/Transforms/LoopLoadElim/opt-size.ll b/test/Transforms/LoopLoadElim/opt-size.ll
new file mode 100644
index 0000000000000..a6322d874f327
--- /dev/null
+++ b/test/Transforms/LoopLoadElim/opt-size.ll
@@ -0,0 +1,76 @@
+; RUN: opt -basicaa -loop-load-elim -S < %s | FileCheck %s
+
+; When optimizing for size don't eliminate in this loop because the loop would
+; have to be versioned first because A and C may alias.
+;
+;   for (unsigned i = 0; i < 100; i++) {
+;     A[i+1] = B[i] + 2;
+;     C[i] = A[i] * 2;
+;   }
+
+target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
+
+; CHECK-LABEL: @f(
+define void @f(i32* %A, i32* %B, i32* %C, i64 %N) optsize {
+
+entry:
+  br label %for.body
+
+for.body:                                         ; preds = %for.body, %entry
+  %indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ]
+  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
+
+  %Aidx_next = getelementptr inbounds i32, i32* %A, i64 %indvars.iv.next
+  %Bidx = getelementptr inbounds i32, i32* %B, i64 %indvars.iv
+  %Cidx = getelementptr inbounds i32, i32* %C, i64 %indvars.iv
+  %Aidx = getelementptr inbounds i32, i32* %A, i64 %indvars.iv
+
+  %b = load i32, i32* %Bidx, align 4
+  %a_p1 = add i32 %b, 2
+  store i32 %a_p1, i32* %Aidx_next, align 4
+
+  %a = load i32, i32* %Aidx, align 4
+; CHECK: %c = mul i32 %a, 2
+  %c = mul i32 %a, 2
+  store i32 %c, i32* %Cidx, align 4
+
+  %exitcond = icmp eq i64 %indvars.iv.next, %N
+  br i1 %exitcond, label %for.end, label %for.body
+
+for.end:                                          ; preds = %for.body
+  ret void
+}
+
+; Same loop but with noalias on %A and %C.  In this case load-eliminate even
+; with -Os.
+
+; CHECK-LABEL: @g(
+define void @g(i32* noalias %A, i32* %B, i32* noalias %C, i64 %N) optsize {
+
+entry:
+  br label %for.body
+
+for.body:                                         ; preds = %for.body, %entry
+  %indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ]
+  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
+
+  %Aidx_next = getelementptr inbounds i32, i32* %A, i64 %indvars.iv.next
+  %Bidx = getelementptr inbounds i32, i32* %B, i64 %indvars.iv
+  %Cidx = getelementptr inbounds i32, i32* %C, i64 %indvars.iv
+  %Aidx = getelementptr inbounds i32, i32* %A, i64 %indvars.iv
+
+  %b = load i32, i32* %Bidx, align 4
+  %a_p1 = add i32 %b, 2
+  store i32 %a_p1, i32* %Aidx_next, align 4
+
+  %a = load i32, i32* %Aidx, align 4
+; CHECK: %c = mul i32 %store_forwarded, 2
+  %c = mul i32 %a, 2
+  store i32 %c, i32* %Cidx, align 4
+
+  %exitcond = icmp eq i64 %indvars.iv.next, %N
+  br i1 %exitcond, label %for.end, label %for.body
+
+for.end:                                          ; preds = %for.body
+  ret void
+}