diff options
Diffstat (limited to 'llvm/test/Transforms/LoopLoadElim/def-store-before-load.ll')
| -rw-r--r-- | llvm/test/Transforms/LoopLoadElim/def-store-before-load.ll | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/llvm/test/Transforms/LoopLoadElim/def-store-before-load.ll b/llvm/test/Transforms/LoopLoadElim/def-store-before-load.ll new file mode 100644 index 00000000000..3dc93f6786e --- /dev/null +++ b/llvm/test/Transforms/LoopLoadElim/def-store-before-load.ll @@ -0,0 +1,35 @@ +; RUN: opt -loop-load-elim -S < %s | FileCheck %s + +; No loop-carried forwarding: The intervening store to A[i] kills the stored +; value from the previous iteration. +; +; for (unsigned i = 0; i < 100; i++) { +; A[i] = 1; +; A[i+1] = A[i] + B[i]; +; } + +target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128" + +define void @f(i32* noalias nocapture %A, i32* noalias nocapture readonly %B, i64 %N) { +entry: + br label %for.body + +for.body: ; preds = %for.body, %entry +; CHECK-NOT: %store_forwarded + %indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ] + %arrayidx = getelementptr inbounds i32, i32* %A, i64 %indvars.iv + store i32 1, i32* %arrayidx, align 4 + %a = load i32, i32* %arrayidx, align 4 + %arrayidxB = getelementptr inbounds i32, i32* %B, i64 %indvars.iv + %b = load i32, i32* %arrayidxB, align 4 +; CHECK: %add = add i32 %b, %a + %add = add i32 %b, %a + %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1 + %arrayidx_next = getelementptr inbounds i32, i32* %A, i64 %indvars.iv.next + store i32 %add, i32* %arrayidx_next, 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 +} |
