171 lines · plain
1; NOTE: Assertions have been autogenerated by utils/update_analyze_test_checks.py2; RUN: opt < %s -disable-output "-passes=print<scalar-evolution>" -scalar-evolution-classify-expressions=0 2>&1 | FileCheck %s3 4; Trip counts with trivial exit conditions.5 6define void @a(i64 %n) nounwind {7; CHECK-LABEL: 'a'8; CHECK-NEXT: Determining loop execution counts for: @a9; CHECK-NEXT: Loop %loop: Unpredictable backedge-taken count.10; CHECK-NEXT: Loop %loop: Unpredictable constant max backedge-taken count.11; CHECK-NEXT: Loop %loop: Unpredictable symbolic max backedge-taken count.12;13entry:14 %t0 = icmp sgt i64 %n, 015 br i1 %t0, label %loop, label %return16 17loop:18 %i = phi i64 [ %i.next, %loop ], [ 0, %entry ]19 %i.next = add nsw i64 %i, 120 %exitcond = icmp eq i64 %i.next, %n21 br i1 false, label %return, label %loop22 23return:24 ret void25}26define void @b(i64 %n) nounwind {27; CHECK-LABEL: 'b'28; CHECK-NEXT: Determining loop execution counts for: @b29; CHECK-NEXT: Loop %loop: backedge-taken count is i1 false30; CHECK-NEXT: Loop %loop: constant max backedge-taken count is i1 false31; CHECK-NEXT: Loop %loop: symbolic max backedge-taken count is i1 false32; CHECK-NEXT: Loop %loop: Trip multiple is 133;34entry:35 %t0 = icmp sgt i64 %n, 036 br i1 %t0, label %loop, label %return37 38loop:39 %i = phi i64 [ %i.next, %loop ], [ 0, %entry ]40 %i.next = add nsw i64 %i, 141 %exitcond = icmp eq i64 %i.next, %n42 br i1 true, label %return, label %loop43 44return:45 ret void46}47define void @c(i64 %n) nounwind {48; CHECK-LABEL: 'c'49; CHECK-NEXT: Determining loop execution counts for: @c50; CHECK-NEXT: Loop %loop: backedge-taken count is i1 false51; CHECK-NEXT: Loop %loop: constant max backedge-taken count is i1 false52; CHECK-NEXT: Loop %loop: symbolic max backedge-taken count is i1 false53; CHECK-NEXT: Loop %loop: Trip multiple is 154;55entry:56 %t0 = icmp sgt i64 %n, 057 br i1 %t0, label %loop, label %return58 59loop:60 %i = phi i64 [ %i.next, %loop ], [ 0, %entry ]61 %i.next = add nsw i64 %i, 162 %exitcond = icmp eq i64 %i.next, %n63 br i1 false, label %loop, label %return64 65return:66 ret void67}68define void @d(i64 %n) nounwind {69; CHECK-LABEL: 'd'70; CHECK-NEXT: Determining loop execution counts for: @d71; CHECK-NEXT: Loop %loop: Unpredictable backedge-taken count.72; CHECK-NEXT: Loop %loop: Unpredictable constant max backedge-taken count.73; CHECK-NEXT: Loop %loop: Unpredictable symbolic max backedge-taken count.74;75entry:76 %t0 = icmp sgt i64 %n, 077 br i1 %t0, label %loop, label %return78 79loop:80 %i = phi i64 [ %i.next, %loop ], [ 0, %entry ]81 %i.next = add nsw i64 %i, 182 %exitcond = icmp eq i64 %i.next, %n83 br i1 true, label %loop, label %return84 85return:86 ret void87}88 89; Trip counts for non-polynomial iterations. It's theoretically possible90; to compute a maximum count for these, but short of that, ScalarEvolution91; should return unknown.92 93; PR741694declare i1 @g() nounwind95 96define void @nonpolynomial() {97; CHECK-LABEL: 'nonpolynomial'98; CHECK-NEXT: Determining loop execution counts for: @nonpolynomial99; CHECK-NEXT: Loop %loophead: Unpredictable backedge-taken count.100; CHECK-NEXT: Loop %loophead: Unpredictable constant max backedge-taken count.101; CHECK-NEXT: Loop %loophead: Unpredictable symbolic max backedge-taken count.102;103entry:104 br label %loophead105loophead:106 %x = phi i32 [0, %entry], [%x.1, %bb1], [%x.2, %bb2]107 %y = icmp slt i32 %x, 100108 br i1 %y, label %loopbody, label %retbb109loopbody:110 %z = call i1 @g()111 br i1 %z, label %bb1, label %bb2112bb1:113 %x.1 = add i32 %x, 2114 br label %loophead115bb2:116 %x.2 = add i32 %x, 3117 br label %loophead118retbb:119 ret void120}121 122; PHI nodes with all constant operands.123 124define void @constant_phi_operands() nounwind {125; CHECK-LABEL: 'constant_phi_operands'126; CHECK-NEXT: Determining loop execution counts for: @constant_phi_operands127; CHECK-NEXT: Loop %loop: backedge-taken count is i32 1128; CHECK-NEXT: Loop %loop: constant max backedge-taken count is i32 1129; CHECK-NEXT: Loop %loop: symbolic max backedge-taken count is i32 1130; CHECK-NEXT: Loop %loop: Trip multiple is 2131;132entry:133 br label %loop134 135loop:136 %i = phi i64 [ 1, %loop ], [ 0, %entry ]137 %exitcond = icmp eq i64 %i, 1138 br i1 %exitcond, label %return, label %loop139 140return:141 ret void142}143 144; PR16130: Loop exit depends on an 'or' expression.145; One side of the expression test against a value that will be skipped.146; We can't assume undefined behavior just because we have an NSW flag.147;148define void @exit_orcond_nsw(ptr %a) nounwind {149; CHECK-LABEL: 'exit_orcond_nsw'150; CHECK-NEXT: Determining loop execution counts for: @exit_orcond_nsw151; CHECK-NEXT: Loop %for.body.i: Unpredictable backedge-taken count.152; CHECK-NEXT: Loop %for.body.i: constant max backedge-taken count is i32 1153; CHECK-NEXT: Loop %for.body.i: symbolic max backedge-taken count is i32 1154;155entry:156 br label %for.body.i157 158for.body.i: ; preds = %for.body.i, %entry159 %b.01.i = phi i32 [ 0, %entry ], [ %add.i, %for.body.i ]160 %tobool.i = icmp ne i32 %b.01.i, 0161 %add.i = add nsw i32 %b.01.i, 8162 %cmp.i = icmp eq i32 %add.i, 13163 %or.cond = or i1 %tobool.i, %cmp.i164 br i1 %or.cond, label %exit, label %for.body.i165 166exit: ; preds = %for.body.i167 %b.01.i.lcssa = phi i32 [ %b.01.i, %for.body.i ]168 store i32 %b.01.i.lcssa, ptr %a, align 4169 ret void170}171