; RUN: opt -S < %s -loop-idiom | FileCheck %s ; CHECK-NOT: memset ; check that memset is not generated (for stores) because that will result ; in udiv hoisted out of the loop by the SCEV Expander ; TODO: ideally we should be able to generate memset ; if SCEV expander is taught to generate the dependencies ; at the right point. @a = global i32 0, align 4 @b = global i32 0, align 4 @c = external local_unnamed_addr global [1 x i8], align 1 define void @e() local_unnamed_addr { entry: %d0 = load i32, i32* @a, align 4 %d1 = load i32, i32* @b, align 4 br label %for.cond1thread-pre-split for.cond1thread-pre-split: ; preds = %for.body5, %entry %div = udiv i32 %d0, %d1 br label %for.body5 for.body5: ; preds = %for.body5, %for.cond1thread-pre-split %indvars.iv = phi i64 [ 0, %for.cond1thread-pre-split ], [ %indvars.iv.next, %for.body5 ] %divx = sext i32 %div to i64 %0 = add nsw i64 %divx, %indvars.iv %arrayidx = getelementptr inbounds [1 x i8], [1 x i8]* @c, i64 0, i64 %0 store i8 0, i8* %arrayidx, align 1 %indvars.iv.next = add nsw i64 %indvars.iv, 1 %1 = trunc i64 %indvars.iv.next to i32 %tobool4 = icmp eq i32 %1, 0 br i1 %tobool4, label %for.cond1thread-pre-split, label %for.body5 } ; The loop's trip count is depending on an unsafe operation ; udiv. SCEV expander hoists it out of the loop, so loop-idiom ; should check that the memset is not generated in this case. define void @f(i32 %a, i32 %b, i8* nocapture %x) local_unnamed_addr { entry: br label %for.body for.body: ; preds = %for.body6, %entry %div = udiv i32 %a, %b %conv = zext i32 %div to i64 br label %for.body6 for.body6: ; preds = %for.body6, %for.body %i.09 = phi i64 [ %inc, %for.body6 ], [ 0, %for.body ] %arrayidx = getelementptr inbounds i8, i8* %x, i64 %i.09 store i8 0, i8* %arrayidx, align 1 %inc = add nuw nsw i64 %i.09, 1 %cmp3 = icmp slt i64 %inc, %conv br i1 %cmp3, label %for.body6, label %for.body }