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1; RUN: opt -passes=loop-load-elim -S < %s | FileCheck %s2 3; Simple st->ld forwarding derived from a lexical forward dep.4;5; for (unsigned i = 0; i < 100; i++) {6; A[i+1] = B[i] + 2;7; C[i] = A[i] * 2;8; }9 10target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"11 12define void @f(ptr %A, ptr %B, ptr %C, i64 %N) {13 14; CHECK: for.body.lver.check:15; CHECK: %found.conflict{{.*}} =16; CHECK-NOT: %found.conflict{{.*}} =17 18entry:19; Make sure the hoisted load keeps the alignment20; CHECK: %load_initial = load i32, ptr %A, align 121 br label %for.body22 23for.body: ; preds = %for.body, %entry24; CHECK: %store_forwarded = phi i32 [ %load_initial, %for.body.ph ], [ %a_p1, %for.body ]25 %indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ]26 %indvars.iv.next = add nuw nsw i64 %indvars.iv, 127 28 %Aidx_next = getelementptr inbounds i32, ptr %A, i64 %indvars.iv.next29 %Bidx = getelementptr inbounds i32, ptr %B, i64 %indvars.iv30 %Cidx = getelementptr inbounds i32, ptr %C, i64 %indvars.iv31 %Aidx = getelementptr inbounds i32, ptr %A, i64 %indvars.iv32 33 %b = load i32, ptr %Bidx, align 434 %a_p1 = add i32 %b, 235 store i32 %a_p1, ptr %Aidx_next, align 436 37 %a = load i32, ptr %Aidx, align 138; CHECK: %c = mul i32 %store_forwarded, 239 %c = mul i32 %a, 240 store i32 %c, ptr %Cidx, align 441 42 %exitcond = icmp eq i64 %indvars.iv.next, %N43 br i1 %exitcond, label %for.end, label %for.body44 45for.end: ; preds = %for.body46 ret void47}48