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1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py2; RUN: opt -S -passes=jump-threading < %s | FileCheck %s3 4define i8 @test(i32 %a, i32 %length) {5; CHECK-LABEL: @test(6; CHECK-NEXT: entry:7; CHECK-NEXT: br label [[BACKEDGE:%.*]]8; CHECK: backedge:9; CHECK-NEXT: [[IV:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[BACKEDGE]] ]10; CHECK-NEXT: [[IV_NEXT]] = add nsw i32 [[IV]], 111; CHECK-NEXT: [[CONT:%.*]] = icmp slt i32 [[IV_NEXT]], 40012; CHECK-NEXT: br i1 [[CONT]], label [[BACKEDGE]], label [[EXIT:%.*]]13; CHECK: exit:14; CHECK-NEXT: ret i8 015;16entry:17 br label %loop18 19loop:20 %iv = phi i32 [0, %entry], [%iv.next, %backedge]21 ;; We can use an inductive argument to prove %iv is always positive22 %cnd = icmp sge i32 %iv, 023 br i1 %cnd, label %backedge, label %exit24 25backedge:26 %iv.next = add nsw i32 %iv, 127 %cont = icmp slt i32 %iv.next, 40028 br i1 %cont, label %loop, label %exit29exit:30 ret i8 031}32 33