1; NOTE: Assertions have been autogenerated by utils/update_analyze_test_checks.py 2; RUN: opt < %s -analyze -enable-new-pm=0 -scalar-evolution -scalar-evolution-classify-expressions=0 | FileCheck %s 3; RUN: opt < %s -disable-output "-passes=print<scalar-evolution>" -scalar-evolution-classify-expressions=0 2>&1 | FileCheck %s 4 5; Trip counts with trivial exit conditions. 6 7define void @a(i64 %n) nounwind { 8; CHECK-LABEL: 'a' 9; CHECK-NEXT: Determining loop execution counts for: @a 10; CHECK-NEXT: Loop %loop: Unpredictable backedge-taken count. 11; CHECK-NEXT: Loop %loop: Unpredictable max backedge-taken count. 12; CHECK-NEXT: Loop %loop: Unpredictable predicated backedge-taken count. 13; 14entry: 15 %t0 = icmp sgt i64 %n, 0 16 br i1 %t0, label %loop, label %return 17 18loop: 19 %i = phi i64 [ %i.next, %loop ], [ 0, %entry ] 20 %i.next = add nsw i64 %i, 1 21 %exitcond = icmp eq i64 %i.next, %n 22 br i1 false, label %return, label %loop 23 24return: 25 ret void 26} 27define void @b(i64 %n) nounwind { 28; CHECK-LABEL: 'b' 29; CHECK-NEXT: Determining loop execution counts for: @b 30; CHECK-NEXT: Loop %loop: backedge-taken count is false 31; CHECK-NEXT: Loop %loop: max backedge-taken count is false 32; CHECK-NEXT: Loop %loop: Predicated backedge-taken count is false 33; CHECK-NEXT: Predicates: 34; CHECK: Loop %loop: Trip multiple is 1 35; 36entry: 37 %t0 = icmp sgt i64 %n, 0 38 br i1 %t0, label %loop, label %return 39 40loop: 41 %i = phi i64 [ %i.next, %loop ], [ 0, %entry ] 42 %i.next = add nsw i64 %i, 1 43 %exitcond = icmp eq i64 %i.next, %n 44 br i1 true, label %return, label %loop 45 46return: 47 ret void 48} 49define void @c(i64 %n) nounwind { 50; CHECK-LABEL: 'c' 51; CHECK-NEXT: Determining loop execution counts for: @c 52; CHECK-NEXT: Loop %loop: backedge-taken count is false 53; CHECK-NEXT: Loop %loop: max backedge-taken count is false 54; CHECK-NEXT: Loop %loop: Predicated backedge-taken count is false 55; CHECK-NEXT: Predicates: 56; CHECK: Loop %loop: Trip multiple is 1 57; 58entry: 59 %t0 = icmp sgt i64 %n, 0 60 br i1 %t0, label %loop, label %return 61 62loop: 63 %i = phi i64 [ %i.next, %loop ], [ 0, %entry ] 64 %i.next = add nsw i64 %i, 1 65 %exitcond = icmp eq i64 %i.next, %n 66 br i1 false, label %loop, label %return 67 68return: 69 ret void 70} 71define void @d(i64 %n) nounwind { 72; CHECK-LABEL: 'd' 73; CHECK-NEXT: Determining loop execution counts for: @d 74; CHECK-NEXT: Loop %loop: Unpredictable backedge-taken count. 75; CHECK-NEXT: Loop %loop: Unpredictable max backedge-taken count. 76; CHECK-NEXT: Loop %loop: Unpredictable predicated backedge-taken count. 77; 78entry: 79 %t0 = icmp sgt i64 %n, 0 80 br i1 %t0, label %loop, label %return 81 82loop: 83 %i = phi i64 [ %i.next, %loop ], [ 0, %entry ] 84 %i.next = add nsw i64 %i, 1 85 %exitcond = icmp eq i64 %i.next, %n 86 br i1 true, label %loop, label %return 87 88return: 89 ret void 90} 91 92; Trip counts for non-polynomial iterations. It's theoretically possible 93; to compute a maximum count for these, but short of that, ScalarEvolution 94; should return unknown. 95 96; PR7416 97declare i1 @g() nounwind 98 99define void @nonpolynomial() { 100; CHECK-LABEL: 'nonpolynomial' 101; CHECK-NEXT: Determining loop execution counts for: @nonpolynomial 102; CHECK-NEXT: Loop %loophead: Unpredictable backedge-taken count. 103; CHECK-NEXT: Loop %loophead: Unpredictable max backedge-taken count. 104; CHECK-NEXT: Loop %loophead: Unpredictable predicated backedge-taken count. 105; 106entry: 107 br label %loophead 108loophead: 109 %x = phi i32 [0, %entry], [%x.1, %bb1], [%x.2, %bb2] 110 %y = icmp slt i32 %x, 100 111 br i1 %y, label %loopbody, label %retbb 112loopbody: 113 %z = call i1 @g() 114 br i1 %z, label %bb1, label %bb2 115bb1: 116 %x.1 = add i32 %x, 2 117 br label %loophead 118bb2: 119 %x.2 = add i32 %x, 3 120 br label %loophead 121retbb: 122 ret void 123} 124 125; PHI nodes with all constant operands. 126 127define void @constant_phi_operands() nounwind { 128; CHECK-LABEL: 'constant_phi_operands' 129; CHECK-NEXT: Determining loop execution counts for: @constant_phi_operands 130; CHECK-NEXT: Loop %loop: backedge-taken count is 1 131; CHECK-NEXT: Loop %loop: max backedge-taken count is 1 132; CHECK-NEXT: Loop %loop: Predicated backedge-taken count is 1 133; CHECK-NEXT: Predicates: 134; CHECK: Loop %loop: Trip multiple is 2 135; 136entry: 137 br label %loop 138 139loop: 140 %i = phi i64 [ 1, %loop ], [ 0, %entry ] 141 %exitcond = icmp eq i64 %i, 1 142 br i1 %exitcond, label %return, label %loop 143 144return: 145 ret void 146} 147 148; PR16130: Loop exit depends on an 'or' expression. 149; One side of the expression test against a value that will be skipped. 150; We can't assume undefined behavior just because we have an NSW flag. 151; 152define void @exit_orcond_nsw(i32 *%a) nounwind { 153; CHECK-LABEL: 'exit_orcond_nsw' 154; CHECK-NEXT: Determining loop execution counts for: @exit_orcond_nsw 155; CHECK-NEXT: Loop %for.body.i: Unpredictable backedge-taken count. 156; CHECK-NEXT: Loop %for.body.i: max backedge-taken count is 1 157; CHECK-NEXT: Loop %for.body.i: Unpredictable predicated backedge-taken count. 158; 159entry: 160 br label %for.body.i 161 162for.body.i: ; preds = %for.body.i, %entry 163 %b.01.i = phi i32 [ 0, %entry ], [ %add.i, %for.body.i ] 164 %tobool.i = icmp ne i32 %b.01.i, 0 165 %add.i = add nsw i32 %b.01.i, 8 166 %cmp.i = icmp eq i32 %add.i, 13 167 %or.cond = or i1 %tobool.i, %cmp.i 168 br i1 %or.cond, label %exit, label %for.body.i 169 170exit: ; preds = %for.body.i 171 %b.01.i.lcssa = phi i32 [ %b.01.i, %for.body.i ] 172 store i32 %b.01.i.lcssa, i32* %a, align 4 173 ret void 174} 175