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; NOTE: Assertions have been autogenerated by utils/update_analyze_test_checks.py
; RUN: opt < %s -analyze -enable-new-pm=0 -scalar-evolution | FileCheck %s
; RUN: opt < %s -disable-output "-passes=print<scalar-evolution>" 2>&1 | FileCheck %s
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"
; Previously in this case the max backedge count would be computed as 1/0, which
; is correct but undesirable. It would also not fold as a constant, tripping
; asserts in SCEV.
define void @pluto(i32 %arg) {
; CHECK-LABEL: 'pluto'
; CHECK-NEXT: Classifying expressions for: @pluto
; CHECK-NEXT: %tmp = ashr i32 %arg, 31
; CHECK-NEXT: --> %tmp U: [-1,1) S: [-1,1)
; CHECK-NEXT: %tmp1 = add nsw i32 %tmp, 2
; CHECK-NEXT: --> (2 + %tmp)<nsw> U: [1,3) S: [1,3)
; CHECK-NEXT: %tmp3 = phi i32 [ 0, %bb ], [ %tmp4, %bb2 ]
; CHECK-NEXT: --> {0,+,(2 + %tmp)<nsw>}<nuw><nsw><%bb2> U: [0,3) S: [0,3) Exits: ((2 + %tmp)<nsw> * (1 /u (2 + %tmp)<nsw>)) LoopDispositions: { %bb2: Computable }
; CHECK-NEXT: %tmp4 = add nuw nsw i32 %tmp1, %tmp3
; CHECK-NEXT: --> {(2 + %tmp)<nsw>,+,(2 + %tmp)<nsw>}<nuw><nsw><%bb2> U: [1,5) S: [1,5) Exits: (2 + ((2 + %tmp)<nsw> * (1 /u (2 + %tmp)<nsw>)) + %tmp) LoopDispositions: { %bb2: Computable }
; CHECK-NEXT: Determining loop execution counts for: @pluto
; CHECK-NEXT: Loop %bb2: backedge-taken count is (1 /u (2 + %tmp)<nsw>)
; CHECK-NEXT: Loop %bb2: max backedge-taken count is 1
; CHECK-NEXT: Loop %bb2: Predicated backedge-taken count is (1 /u (2 + %tmp)<nsw>)
; CHECK-NEXT: Predicates:
; CHECK: Loop %bb2: Trip multiple is 1
;
bb:
%tmp = ashr i32 %arg, 31
%tmp1 = add nsw i32 %tmp, 2
br label %bb2
bb2: ; preds = %bb2, %bb
%tmp3 = phi i32 [ 0, %bb ], [ %tmp4, %bb2 ]
%tmp4 = add nuw nsw i32 %tmp1, %tmp3
%tmp5 = icmp ult i32 %tmp4, 2
br i1 %tmp5, label %bb2, label %bb6
bb6: ; preds = %bb2
ret void
}
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