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1; RUN: opt -S -unroll-runtime -passes=loop-unroll < %s | FileCheck %s2 3target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128"4 5;; Check that we don't emit expensive instructions to compute trip6;; counts when unrolling loops.7 8define i32 @test(i64 %v12, ptr %array, ptr %loc) {9; CHECK-LABEL: @test(10; CHECK-NOT: udiv11entry:12 %step = load i64, ptr %loc, !range !013 br label %loop14 15loop: ; preds = %entry, %loop16 %k.015 = phi i64 [ %v15, %loop ], [ %v12, %entry ]17 %v14 = getelementptr inbounds i8, ptr %array, i64 %k.01518 store i8 0, ptr %v1419 %v15 = add nuw nsw i64 %k.015, %step20 %v16 = icmp slt i64 %v15, 819321 br i1 %v16, label %loop, label %loopexit22 23loopexit: ; preds = %loop24 ret i32 025}26 27;; Though SCEV for loop tripcount contains division,28;; it shouldn't be considered expensive, since the division already29;; exists in the code and we don't need to expand it once more.30;; Thus, it shouldn't prevent us from unrolling the loop.31 32define i32 @test2(ptr %loc, i64 %conv7) {33; CHECK-LABEL: @test2(34; CHECK: udiv35; CHECK: udiv36; CHECK-NOT: udiv37; CHECK-LABEL: for.body38entry:39 %rem0 = load i64, ptr %loc, align 840 %ExpensiveComputation = udiv i64 %rem0, 42 ; <<< Extra computations are added to the trip-count expression41 br label %bb142bb1:43 %div11 = udiv i64 %ExpensiveComputation, %conv744 %cmp.i38 = icmp ugt i64 %div11, 145 %div12 = select i1 %cmp.i38, i64 %div11, i64 146 br label %for.body47for.body:48 %rem1 = phi i64 [ %rem0, %bb1 ], [ %rem2, %for.body ]49 %k1 = phi i64 [ %div12, %bb1 ], [ %dec, %for.body ]50 %mul1 = mul i64 %rem1, 4827151 %rem2 = urem i64 %mul1, 214748364752 %dec = add i64 %k1, -153 %cmp = icmp eq i64 %dec, 054 br i1 %cmp, label %exit, label %for.body55exit:56 %rem3 = phi i64 [ %rem2, %for.body ]57 store i64 %rem3, ptr %loc, align 858 ret i32 059}60 61!0 = !{i64 1, i64 100}62