1 ; RUN: opt -S -loop-load-elim < %s | FileCheck %s 2 3 ; We can't hoist conditional loads to the preheader for the initial value. 4 ; E.g. in the loop below we'd access array[-1] if we did: 5 ; 6 ; for(int i = 0 ; i < n ; i++ ) 7 ; array[i] = ( i > 0 ? array[i - 1] : 0 ) + 4; 8 9 target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128" 10 target triple = "x86_64-apple-macosx10.11.0" 11 12 define void @f(i32* %array, i32 %n) { 13 entry: 14 %cmp10 = icmp sgt i32 %n, 0 15 br i1 %cmp10, label %for.body, label %for.cond.cleanup 16 17 for.cond.cleanup: ; preds = %cond.end, %entry 18 ret void 19 20 for.body: ; preds = %entry, %cond.end 21 %indvars.iv = phi i64 [ %indvars.iv.next, %cond.end ], [ 0, %entry ] 22 ; CHECK-NOT: %store_forwarded = phi 23 %cmp1 = icmp sgt i64 %indvars.iv, 0 24 br i1 %cmp1, label %cond.true, label %cond.end 25 26 cond.true: ; preds = %for.body 27 %0 = add nsw i64 %indvars.iv, -1 28 %arrayidx = getelementptr inbounds i32, i32* %array, i64 %0 29 %1 = load i32, i32* %arrayidx, align 4 30 br label %cond.end 31 32 cond.end: ; preds = %for.body, %cond.true 33 %cond = phi i32 [ %1, %cond.true ], [ 0, %for.body ] 34 ; CHECK: %cond = phi i32 [ %1, %cond.true ], [ 0, %for.body ] 35 %add = add nsw i32 %cond, 4 36 %arrayidx3 = getelementptr inbounds i32, i32* %array, i64 %indvars.iv 37 store i32 %add, i32* %arrayidx3, align 4 38 %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1 39 %lftr.wideiv = trunc i64 %indvars.iv.next to i32 40 %exitcond = icmp eq i32 %lftr.wideiv, %n 41 br i1 %exitcond, label %for.cond.cleanup, label %for.body 42 } 43
