1 ; RUN: opt -S < %s -analyze -scalar-evolution -loop-simplify -scalar-evolution | FileCheck %s 2 3 ; Provide legal integer types. 4 target datalayout = "n8:16:32:64" 5 6 @maxStat = external global i32 7 8 ; LoopSimplify should invalidate SCEV when splitting out the 9 ; inner loop. 10 ; 11 ; First SCEV print: 12 ; CHECK-LABEL: Classifying expressions for: @test 13 ; CHECK: %[[PHI:.*]] = phi i32 [ 0, %entry ], [ %{{.*}}, %if.then5 ], [ %[[PHI]], %if.end ] 14 ; CHECK-LABEL: Determining loop execution counts for: @test 15 ; CHECK: Loop %for.body18: Unpredictable backedge-taken count. 16 ; CHECK: Loop %for.body18: max backedge-taken count is 2147483646 17 ; CHECK: Loop %for.body18: Unpredictable predicated backedge-taken count. 18 ; CHECK: Loop %for.cond: <multiple exits> Unpredictable backedge-taken count. 19 ; CHECK: Loop %for.cond: Unpredictable max backedge-taken count. 20 ; CHECK: Loop %for.cond: Unpredictable predicated backedge-taken count. 21 ; 22 ; Now simplify the loop, which should cause SCEV to re-compute more precise 23 ; info here in addition to having preheader PHIs. Second SCEV print: 24 ; CHECK-LABEL: Classifying expressions for: @test 25 ; CHECK: phi i32 [ %{{.*}}, %if.then5 ], [ 0, %entry ] 26 ; CHECK-LABEL: Determining loop execution counts for: @test 27 ; CHECK: Loop %for.body18: Unpredictable backedge-taken count. 28 ; CHECK: Loop %for.body18: max backedge-taken count is 2147483646 29 ; CHECK: Loop %for.body18: Unpredictable predicated backedge-taken count. 30 ; CHECK: Loop %for.cond: <multiple exits> Unpredictable backedge-taken count. 31 ; CHECK: Loop %for.cond: max backedge-taken count is -2147483647 32 ; CHECK: Loop %for.cond: Unpredictable predicated backedge-taken count. 33 ; CHECK: Loop %for.cond.outer: <multiple exits> Unpredictable backedge-taken count. 34 ; CHECK: Loop %for.cond.outer: Unpredictable max backedge-taken count. 35 ; CHECK: Loop %for.cond.outer: Unpredictable predicated backedge-taken count. 36 define i32 @test() nounwind { 37 entry: 38 br label %for.cond 39 40 for.cond: ; preds = %if.then5, %if.end, %entry 41 %cuts.1 = phi i32 [ 0, %entry ], [ %inc, %if.then5 ], [ %cuts.1, %if.end ] 42 %0 = phi i32 [ 0, %entry ], [ %add, %if.end ], [ %add, %if.then5 ] 43 %add = add i32 %0, 1 44 %cmp = icmp slt i32 %0, 1 45 %tmp1 = load i32, i32* @maxStat, align 4 46 br i1 %cmp, label %for.body, label %for.cond14.preheader 47 48 for.cond14.preheader: ; preds = %for.cond 49 %cmp1726 = icmp sgt i32 %tmp1, 0 50 br i1 %cmp1726, label %for.body18, label %return 51 52 for.body: ; preds = %for.cond 53 %cmp2 = icmp sgt i32 %tmp1, 100 54 br i1 %cmp2, label %return, label %if.end 55 56 if.end: ; preds = %for.body 57 %cmp4 = icmp sgt i32 %tmp1, -1 58 br i1 %cmp4, label %if.then5, label %for.cond 59 60 if.then5: ; preds = %if.end 61 call void @foo() nounwind 62 %inc = add i32 %cuts.1, 1 63 br label %for.cond 64 65 for.body18: ; preds = %for.body18, %for.cond14.preheader 66 %i13.027 = phi i32 [ %1, %for.body18 ], [ 0, %for.cond14.preheader ] 67 call void @foo() nounwind 68 %1 = add nsw i32 %i13.027, 1 69 %tmp16 = load i32, i32* @maxStat, align 4 70 %cmp17 = icmp slt i32 %1, %tmp16 71 br i1 %cmp17, label %for.body18, label %return 72 73 return: ; preds = %for.body18, %for.body, %for.cond14.preheader 74 ret i32 0 75 } 76 77 declare void @foo() nounwind 78 79 ; Notify SCEV when removing an ExitingBlock. This only changes the 80 ; backedge-taken information. 81 ; 82 ; First SCEV print: 83 ; CHECK-LABEL: Determining loop execution counts for: @mergeExit 84 ; CHECK: Loop %while.cond191: <multiple exits> Unpredictable backedge-taken count. 85 ; CHECK: Loop %while.cond191: max backedge-taken count is -1 86 ; CHECK: Loop %while.cond191: Unpredictable predicated backedge-taken count. 87 ; CHECK: Loop %while.cond191.outer: <multiple exits> Unpredictable backedge-taken count. 88 ; CHECK: Loop %while.cond191.outer: Unpredictable max backedge-taken count. 89 ; CHECK: Loop %while.cond191.outer: Unpredictable predicated backedge-taken count. 90 ; 91 ; After simplifying, the max backedge count is refined. 92 ; Second SCEV print: 93 ; CHECK-LABEL: Determining loop execution counts for: @mergeExit 94 ; CHECK: Loop %while.cond191: <multiple exits> backedge-taken count is 0 95 ; CHECK: Loop %while.cond191: max backedge-taken count is 0 96 ; CHECK: Loop %while.cond191: Predicated backedge-taken count is 0 97 ; CHECK: Loop %while.cond191.outer: <multiple exits> Unpredictable backedge-taken count. 98 ; CHECK: Loop %while.cond191.outer: max backedge-taken count is false 99 ; CHECK: Loop %while.cond191.outer: Unpredictable predicated backedge-taken count. 100 define void @mergeExit(i32 %MapAttrCount) nounwind uwtable ssp { 101 entry: 102 br i1 undef, label %if.then124, label %if.end126 103 104 if.then124: ; preds = %entry 105 unreachable 106 107 if.end126: ; preds = %entry 108 br i1 undef, label %while.body.lr.ph, label %if.end591 109 110 while.body.lr.ph: ; preds = %if.end126 111 br i1 undef, label %if.end140, label %if.then137 112 113 if.then137: ; preds = %while.body.lr.ph 114 unreachable 115 116 if.end140: ; preds = %while.body.lr.ph 117 br i1 undef, label %while.cond191.outer, label %if.then148 118 119 if.then148: ; preds = %if.end140 120 unreachable 121 122 while.cond191.outer: ; preds = %if.then205, %if.end140 123 br label %while.cond191 124 125 while.cond191: ; preds = %while.body197, %while.cond191.outer 126 %CppIndex.0 = phi i32 [ %inc, %while.body197 ], [ undef, %while.cond191.outer ] 127 br i1 undef, label %land.rhs, label %if.then216 128 129 land.rhs: ; preds = %while.cond191 130 %inc = add i32 %CppIndex.0, 1 131 %cmp196 = icmp ult i32 %inc, %MapAttrCount 132 br i1 %cmp196, label %while.body197, label %if.then216 133 134 while.body197: ; preds = %land.rhs 135 br i1 undef, label %if.then205, label %while.cond191 136 137 if.then205: ; preds = %while.body197 138 br label %while.cond191.outer 139 140 if.then216: ; preds = %land.rhs, %while.cond191 141 br i1 undef, label %if.else, label %if.then221 142 143 if.then221: ; preds = %if.then216 144 unreachable 145 146 if.else: ; preds = %if.then216 147 br i1 undef, label %if.then266, label %if.end340 148 149 if.then266: ; preds = %if.else 150 switch i32 undef, label %if.else329 [ 151 i32 17, label %if.then285 152 i32 19, label %if.then285 153 i32 18, label %if.then285 154 i32 15, label %if.then285 155 ] 156 157 if.then285: ; preds = %if.then266, %if.then266, %if.then266, %if.then266 158 br i1 undef, label %if.then317, label %if.else324 159 160 if.then317: ; preds = %if.then285 161 br label %if.end340 162 163 if.else324: ; preds = %if.then285 164 unreachable 165 166 if.else329: ; preds = %if.then266 167 unreachable 168 169 if.end340: ; preds = %if.then317, %if.else 170 unreachable 171 172 if.end591: ; preds = %if.end126 173 br i1 undef, label %cond.end, label %cond.false 174 175 cond.false: ; preds = %if.end591 176 unreachable 177 178 cond.end: ; preds = %if.end591 179 ret void 180 } 181
