1; RUN: opt -loop-idiom < %s -mtriple=x86_64-apple-darwin -mcpu=corei7 -S | FileCheck %s 2 3;To recognize this pattern: 4;int popcount(unsigned long long a) { 5; int c = 0; 6; while (a) { 7; c++; 8; a &= a - 1; 9; } 10; return c; 11;} 12; 13; CHECK: entry 14; CHECK: llvm.ctpop.i64 15; CHECK: ret 16define i32 @popcount(i64 %a) nounwind uwtable readnone ssp { 17entry: 18 %tobool3 = icmp eq i64 %a, 0 19 br i1 %tobool3, label %while.end, label %while.body 20 21while.body: ; preds = %entry, %while.body 22 %c.05 = phi i32 [ %inc, %while.body ], [ 0, %entry ] 23 %a.addr.04 = phi i64 [ %and, %while.body ], [ %a, %entry ] 24 %inc = add nsw i32 %c.05, 1 25 %sub = add i64 %a.addr.04, -1 26 %and = and i64 %sub, %a.addr.04 27 %tobool = icmp eq i64 %and, 0 28 br i1 %tobool, label %while.end, label %while.body 29 30while.end: ; preds = %while.body, %entry 31 %c.0.lcssa = phi i32 [ 0, %entry ], [ %inc, %while.body ] 32 ret i32 %c.0.lcssa 33} 34 35; To recognize this pattern: 36;int popcount(unsigned long long a, int mydata1, int mydata2) { 37; int c = 0; 38; while (a) { 39; c++; 40; a &= a - 1; 41; mydata1 *= c; 42; mydata2 *= (int)a; 43; } 44; return c + mydata1 + mydata2; 45;} 46; CHECK: entry 47; CHECK: llvm.ctpop.i64 48; CHECK: ret 49define i32 @popcount2(i64 %a, i32 %mydata1, i32 %mydata2) nounwind uwtable readnone ssp { 50entry: 51 %tobool9 = icmp eq i64 %a, 0 52 br i1 %tobool9, label %while.end, label %while.body 53 54while.body: ; preds = %entry, %while.body 55 %c.013 = phi i32 [ %inc, %while.body ], [ 0, %entry ] 56 %mydata2.addr.012 = phi i32 [ %mul1, %while.body ], [ %mydata2, %entry ] 57 %mydata1.addr.011 = phi i32 [ %mul, %while.body ], [ %mydata1, %entry ] 58 %a.addr.010 = phi i64 [ %and, %while.body ], [ %a, %entry ] 59 %inc = add nsw i32 %c.013, 1 60 %sub = add i64 %a.addr.010, -1 61 %and = and i64 %sub, %a.addr.010 62 %mul = mul nsw i32 %inc, %mydata1.addr.011 63 %conv = trunc i64 %and to i32 64 %mul1 = mul nsw i32 %conv, %mydata2.addr.012 65 %tobool = icmp eq i64 %and, 0 66 br i1 %tobool, label %while.end, label %while.body 67 68while.end: ; preds = %while.body, %entry 69 %c.0.lcssa = phi i32 [ 0, %entry ], [ %inc, %while.body ] 70 %mydata2.addr.0.lcssa = phi i32 [ %mydata2, %entry ], [ %mul1, %while.body ] 71 %mydata1.addr.0.lcssa = phi i32 [ %mydata1, %entry ], [ %mul, %while.body ] 72 %add = add i32 %mydata2.addr.0.lcssa, %mydata1.addr.0.lcssa 73 %add2 = add i32 %add, %c.0.lcssa 74 ret i32 %add2 75} 76 77; Some variants once cause crash 78target triple = "x86_64-apple-macosx10.8.0" 79 80define i32 @PopCntCrash1(i64 %a) nounwind uwtable readnone ssp { 81entry: 82 %tobool3 = icmp eq i64 %a, 0 83 br i1 %tobool3, label %while.end, label %while.body 84 85while.body: ; preds = %entry, %while.body 86 %c.05 = phi i32 [ %inc, %while.body ], [ 0, %entry ] 87 %a.addr.04 = phi i64 [ %and, %while.body ], [ %a, %entry ] 88 %t = add i32 %c.05, %c.05 89 %inc = add nsw i32 %t, 1 90 %sub = add i64 %a.addr.04, -1 91 %and = and i64 %sub, %a.addr.04 92 %tobool = icmp eq i64 %and, 0 93 br i1 %tobool, label %while.end, label %while.body 94 95while.end: ; preds = %while.body, %entry 96 %c.0.lcssa = phi i32 [ 0, %entry ], [ %inc, %while.body ] 97 ret i32 %c.0.lcssa 98 99; CHECK: entry 100; CHECK: ret 101} 102 103define i32 @PopCntCrash2(i64 %a, i32 %b) nounwind uwtable readnone ssp { 104entry: 105 %tobool3 = icmp eq i64 %a, 0 106 br i1 %tobool3, label %while.end, label %while.body 107 108while.body: ; preds = %entry, %while.body 109 %c.05 = phi i32 [ %inc, %while.body ], [ %b, %entry ] 110 %a.addr.04 = phi i64 [ %and, %while.body ], [ %a, %entry ] 111 %inc = add nsw i32 %c.05, 1 112 %sub = add i64 %a.addr.04, -1 113 %and = and i64 %sub, %a.addr.04 114 %tobool = icmp eq i64 %and, 0 115 br i1 %tobool, label %while.end, label %while.body 116 117while.end: ; preds = %while.body, %entry 118 %c.0.lcssa = phi i32 [ 0, %entry ], [ %inc, %while.body ] 119 ret i32 %c.0.lcssa 120} 121 122define i32 @PopCntCrash3(i64 %a, i32 %x) { 123entry: 124 %tobool3 = icmp eq i64 %a, 0 125 %cmp = icmp eq i32 %x, 0 126 br i1 %tobool3, label %while.end, label %while.body 127 128while.body: ; preds = %entry, %while.body 129 %c.05 = phi i32 [ %inc, %while.body ], [ 0, %entry ] 130 %a.addr.04 = phi i64 [ %and, %while.body ], [ %a, %entry ] 131 %inc = add nsw i32 %c.05, 1 132 %sub = add i64 %a.addr.04, -1 133 %and = and i64 %sub, %a.addr.04 134 %tobool = icmp eq i64 %and, 0 135 br i1 %cmp, label %while.end, label %while.body 136 137while.end: ; preds = %while.body, %entry 138 %c.0.lcssa = phi i32 [ 0, %entry ], [ %inc, %while.body ] 139 ret i32 %c.0.lcssa 140} 141