1 ; RUN: opt -loop-load-elim -S < %s | FileCheck %s 2 ; RUN: opt -passes=loop-load-elim -S < %s | FileCheck %s 3 4 ; Simple st->ld forwarding derived from a lexical backward dep. 5 ; 6 ; for (unsigned i = 0; i < 100; i++) 7 ; A[i+1] = A[i] + B[i]; 8 9 target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128" 10 11 define void @f(i32* noalias nocapture %A, i32* noalias nocapture readonly %B, i64 %N) { 12 entry: 13 ; CHECK: %load_initial = load i32, i32* %A 14 br label %for.body 15 16 for.body: ; preds = %for.body, %entry 17 ; CHECK: %store_forwarded = phi i32 [ %load_initial, %entry ], [ %add, %for.body ] 18 %indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ] 19 %arrayidx = getelementptr inbounds i32, i32* %A, i64 %indvars.iv 20 %load = load i32, i32* %arrayidx, align 4 21 %arrayidx2 = getelementptr inbounds i32, i32* %B, i64 %indvars.iv 22 %load_1 = load i32, i32* %arrayidx2, align 4 23 ; CHECK: %add = add i32 %load_1, %store_forwarded 24 %add = add i32 %load_1, %load 25 %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1 26 %arrayidx_next = getelementptr inbounds i32, i32* %A, i64 %indvars.iv.next 27 store i32 %add, i32* %arrayidx_next, align 4 28 %exitcond = icmp eq i64 %indvars.iv.next, %N 29 br i1 %exitcond, label %for.end, label %for.body 30 31 for.end: ; preds = %for.body 32 ret void 33 } 34
