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1; Test the static branch probability heuristics for no-return functions.2; RUN: opt < %s -passes='print<branch-prob>' --disable-output 2>&1 | FileCheck %s3 4declare void @g1()5declare void @g2()6declare void @g3()7declare void @g4()8declare i32 @g5()9 10define void @test1(i32 %a, i32 %b) {11entry:12 br label %do.body13; CHECK: edge %entry -> %do.body probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]14 15do.body:16 %i.0 = phi i32 [ 0, %entry ], [ %inc3, %do.end ]17 call void @g1()18 br label %do.body119; CHECK: edge %do.body -> %do.body1 probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]20 21do.body1:22 %j.0 = phi i32 [ 0, %do.body ], [ %inc, %do.body1 ]23 call void @g2()24 %inc = add nsw i32 %j.0, 125 %cmp = icmp slt i32 %inc, %b26 br i1 %cmp, label %do.body1, label %do.end27; CHECK: edge %do.body1 -> %do.body1 probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]28; CHECK: edge %do.body1 -> %do.end probability is 0x04000000 / 0x80000000 = 3.12%29 30do.end:31 call void @g3()32 %inc3 = add nsw i32 %i.0, 133 %cmp4 = icmp slt i32 %inc3, %a34 br i1 %cmp4, label %do.body, label %do.end535; CHECK: edge %do.end -> %do.body probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]36; CHECK: edge %do.end -> %do.end5 probability is 0x04000000 / 0x80000000 = 3.12%37 38do.end5:39 call void @g4()40 ret void41}42 43define void @test2(i32 %a, i32 %b) {44entry:45 %cmp9 = icmp sgt i32 %a, 046 br i1 %cmp9, label %for.body.lr.ph, label %for.end647; CHECK: edge %entry -> %for.body.lr.ph probability is 0x50000000 / 0x80000000 = 62.50%48; CHECK: edge %entry -> %for.end6 probability is 0x30000000 / 0x80000000 = 37.50%49 50for.body.lr.ph:51 %cmp27 = icmp sgt i32 %b, 052 br label %for.body53; CHECK: edge %for.body.lr.ph -> %for.body probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]54 55for.body:56 %i.010 = phi i32 [ 0, %for.body.lr.ph ], [ %inc5, %for.end ]57 call void @g1()58 br i1 %cmp27, label %for.body3, label %for.end59; CHECK: edge %for.body -> %for.body3 probability is 0x50000000 / 0x80000000 = 62.50%60; CHECK: edge %for.body -> %for.end probability is 0x30000000 / 0x80000000 = 37.50%61 62for.body3:63 %j.08 = phi i32 [ %inc, %for.body3 ], [ 0, %for.body ]64 call void @g2()65 %inc = add nsw i32 %j.08, 166 %exitcond = icmp eq i32 %inc, %b67 br i1 %exitcond, label %for.end, label %for.body368; CHECK: edge %for.body3 -> %for.end probability is 0x04000000 / 0x80000000 = 3.12%69; CHECK: edge %for.body3 -> %for.body3 probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]70 71for.end:72 call void @g3()73 %inc5 = add nsw i32 %i.010, 174 %exitcond11 = icmp eq i32 %inc5, %a75 br i1 %exitcond11, label %for.end6, label %for.body76; CHECK: edge %for.end -> %for.end6 probability is 0x04000000 / 0x80000000 = 3.12%77; CHECK: edge %for.end -> %for.body probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]78 79for.end6:80 call void @g4()81 ret void82}83 84define void @test3(i32 %a, i32 %b, ptr %c) {85entry:86 br label %do.body87; CHECK: edge %entry -> %do.body probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]88 89do.body:90 %i.0 = phi i32 [ 0, %entry ], [ %inc4, %if.end ]91 call void @g1()92 %0 = load i32, ptr %c, align 493 %cmp = icmp slt i32 %0, 4294 br i1 %cmp, label %do.body1, label %if.end95; CHECK: edge %do.body -> %do.body1 probability is 0x40000000 / 0x80000000 = 50.00%96; CHECK: edge %do.body -> %if.end probability is 0x40000000 / 0x80000000 = 50.00%97 98do.body1:99 %j.0 = phi i32 [ %inc, %do.body1 ], [ 0, %do.body ]100 call void @g2()101 %inc = add nsw i32 %j.0, 1102 %cmp2 = icmp slt i32 %inc, %b103 br i1 %cmp2, label %do.body1, label %if.end104; CHECK: edge %do.body1 -> %do.body1 probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]105; CHECK: edge %do.body1 -> %if.end probability is 0x04000000 / 0x80000000 = 3.12%106 107if.end:108 call void @g3()109 %inc4 = add nsw i32 %i.0, 1110 %cmp5 = icmp slt i32 %inc4, %a111 br i1 %cmp5, label %do.body, label %do.end6112; CHECK: edge %if.end -> %do.body probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]113; CHECK: edge %if.end -> %do.end6 probability is 0x04000000 / 0x80000000 = 3.12%114 115do.end6:116 call void @g4()117 ret void118}119 120define void @test4(i32 %a, i32 %b, ptr %c) {121entry:122 br label %do.body123; CHECK: edge %entry -> %do.body probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]124 125do.body:126 %i.0 = phi i32 [ 0, %entry ], [ %inc4, %do.end ]127 call void @g1()128 %0 = load i32, ptr %c, align 4129 %cmp = icmp slt i32 %0, 42130 br i1 %cmp, label %return, label %do.body1131; CHECK: edge %do.body -> %return probability is 0x04000000 / 0x80000000 = 3.12%132; CHECK: edge %do.body -> %do.body1 probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]133 134do.body1:135 %j.0 = phi i32 [ %inc, %do.body1 ], [ 0, %do.body ]136 call void @g2()137 %inc = add nsw i32 %j.0, 1138 %cmp2 = icmp slt i32 %inc, %b139 br i1 %cmp2, label %do.body1, label %do.end140; CHECK: edge %do.body1 -> %do.body1 probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]141; CHECK: edge %do.body1 -> %do.end probability is 0x04000000 / 0x80000000 = 3.12%142 143do.end:144 call void @g3()145 %inc4 = add nsw i32 %i.0, 1146 %cmp5 = icmp slt i32 %inc4, %a147 br i1 %cmp5, label %do.body, label %do.end6148; CHECK: edge %do.end -> %do.body probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]149; CHECK: edge %do.end -> %do.end6 probability is 0x04000000 / 0x80000000 = 3.12%150 151do.end6:152 call void @g4()153 br label %return154; CHECK: edge %do.end6 -> %return probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]155 156return:157 ret void158}159 160define void @test5(i32 %a, i32 %b, ptr %c) {161entry:162 br label %do.body163; CHECK: edge %entry -> %do.body probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]164 165do.body:166 %i.0 = phi i32 [ 0, %entry ], [ %inc4, %do.end ]167 call void @g1()168 br label %do.body1169; CHECK: edge %do.body -> %do.body1 probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]170 171do.body1:172 %j.0 = phi i32 [ 0, %do.body ], [ %inc, %if.end ]173 %0 = load i32, ptr %c, align 4174 %cmp = icmp slt i32 %0, 42175 br i1 %cmp, label %return, label %if.end176; CHECK: edge %do.body1 -> %return probability is 0x04000000 / 0x80000000 = 3.12%177; CHECK: edge %do.body1 -> %if.end probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]178 179if.end:180 call void @g2()181 %inc = add nsw i32 %j.0, 1182 %cmp2 = icmp slt i32 %inc, %b183 br i1 %cmp2, label %do.body1, label %do.end184; CHECK: edge %if.end -> %do.body1 probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]185; CHECK: edge %if.end -> %do.end probability is 0x04000000 / 0x80000000 = 3.12%186 187do.end:188 call void @g3()189 %inc4 = add nsw i32 %i.0, 1190 %cmp5 = icmp slt i32 %inc4, %a191 br i1 %cmp5, label %do.body, label %do.end6192; CHECK: edge %do.end -> %do.body probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]193; CHECK: edge %do.end -> %do.end6 probability is 0x04000000 / 0x80000000 = 3.12%194 195do.end6:196 call void @g4()197 br label %return198; CHECK: edge %do.end6 -> %return probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]199 200return:201 ret void202}203 204define void @test6(i32 %a, i32 %b, ptr %c) {205entry:206 br label %do.body207; CHECK: edge %entry -> %do.body probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]208 209do.body:210 %i.0 = phi i32 [ 0, %entry ], [ %inc4, %do.end ]211 call void @g1()212 br label %do.body1213; CHECK: edge %do.body -> %do.body1 probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]214 215do.body1:216 %j.0 = phi i32 [ 0, %do.body ], [ %inc, %do.cond ]217 call void @g2()218 %0 = load i32, ptr %c, align 4219 %cmp = icmp slt i32 %0, 42220 br i1 %cmp, label %return, label %do.cond221; CHECK: edge %do.body1 -> %return probability is 0x04000000 / 0x80000000 = 3.12%222; CHECK: edge %do.body1 -> %do.cond probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]223 224do.cond:225 %inc = add nsw i32 %j.0, 1226 %cmp2 = icmp slt i32 %inc, %b227 br i1 %cmp2, label %do.body1, label %do.end228; CHECK: edge %do.cond -> %do.body1 probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]229; CHECK: edge %do.cond -> %do.end probability is 0x04000000 / 0x80000000 = 3.12%230 231do.end:232 call void @g3()233 %inc4 = add nsw i32 %i.0, 1234 %cmp5 = icmp slt i32 %inc4, %a235 br i1 %cmp5, label %do.body, label %do.end6236; CHECK: edge %do.end -> %do.body probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]237; CHECK: edge %do.end -> %do.end6 probability is 0x04000000 / 0x80000000 = 3.12%238 239do.end6:240 call void @g4()241 br label %return242; CHECK: edge %do.end6 -> %return probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]243 244return:245 ret void246}247 248define void @test7(i32 %a, i32 %b, ptr %c) {249entry:250 %cmp10 = icmp sgt i32 %a, 0251 br i1 %cmp10, label %for.body.lr.ph, label %for.end7252; CHECK: edge %entry -> %for.body.lr.ph probability is 0x50000000 / 0x80000000 = 62.50%253; CHECK: edge %entry -> %for.end7 probability is 0x30000000 / 0x80000000 = 37.50%254 255for.body.lr.ph:256 %cmp38 = icmp sgt i32 %b, 0257 br label %for.body258; CHECK: edge %for.body.lr.ph -> %for.body probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]259 260for.body:261 %i.011 = phi i32 [ 0, %for.body.lr.ph ], [ %inc6, %for.inc5 ]262 %0 = load i32, ptr %c, align 4263 %cmp1 = icmp eq i32 %0, %i.011264 br i1 %cmp1, label %for.inc5, label %if.end265; CHECK: edge %for.body -> %for.inc5 probability is 0x40000000 / 0x80000000 = 50.00%266; CHECK: edge %for.body -> %if.end probability is 0x40000000 / 0x80000000 = 50.00%267 268if.end:269 call void @g1()270 br i1 %cmp38, label %for.body4, label %for.end271; CHECK: edge %if.end -> %for.body4 probability is 0x50000000 / 0x80000000 = 62.50%272; CHECK: edge %if.end -> %for.end probability is 0x30000000 / 0x80000000 = 37.50%273 274for.body4:275 %j.09 = phi i32 [ %inc, %for.body4 ], [ 0, %if.end ]276 call void @g2()277 %inc = add nsw i32 %j.09, 1278 %exitcond = icmp eq i32 %inc, %b279 br i1 %exitcond, label %for.end, label %for.body4280; CHECK: edge %for.body4 -> %for.end probability is 0x04000000 / 0x80000000 = 3.12%281; CHECK: edge %for.body4 -> %for.body4 probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]282 283for.end:284 call void @g3()285 br label %for.inc5286; CHECK: edge %for.end -> %for.inc5 probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]287 288for.inc5:289 %inc6 = add nsw i32 %i.011, 1290 %exitcond12 = icmp eq i32 %inc6, %a291 br i1 %exitcond12, label %for.end7, label %for.body292; CHECK: edge %for.inc5 -> %for.end7 probability is 0x04000000 / 0x80000000 = 3.12%293; CHECK: edge %for.inc5 -> %for.body probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]294 295for.end7:296 call void @g4()297 ret void298}299 300define void @test8(i32 %a, i32 %b, ptr %c) {301entry:302 %cmp18 = icmp sgt i32 %a, 0303 br i1 %cmp18, label %for.body.lr.ph, label %for.end15304; CHECK: edge %entry -> %for.body.lr.ph probability is 0x50000000 / 0x80000000 = 62.50%305; CHECK: edge %entry -> %for.end15 probability is 0x30000000 / 0x80000000 = 37.50%306 307for.body.lr.ph:308 %cmp216 = icmp sgt i32 %b, 0309 %arrayidx5 = getelementptr inbounds i32, ptr %c, i64 1310 %arrayidx9 = getelementptr inbounds i32, ptr %c, i64 2311 br label %for.body312; CHECK: edge %for.body.lr.ph -> %for.body probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]313 314for.body:315 %i.019 = phi i32 [ 0, %for.body.lr.ph ], [ %inc14, %for.end ]316 call void @g1()317 br i1 %cmp216, label %for.body3, label %for.end318; CHECK: edge %for.body -> %for.body3 probability is 0x50000000 / 0x80000000 = 62.50%319; CHECK: edge %for.body -> %for.end probability is 0x30000000 / 0x80000000 = 37.50%320 321for.body3:322 %j.017 = phi i32 [ 0, %for.body ], [ %inc, %for.inc ]323 %0 = load i32, ptr %c, align 4324 %cmp4 = icmp eq i32 %0, %j.017325 br i1 %cmp4, label %for.inc, label %if.end326; CHECK: edge %for.body3 -> %for.inc probability is 0x40000000 / 0x80000000 = 50.00%327; CHECK: edge %for.body3 -> %if.end probability is 0x40000000 / 0x80000000 = 50.00%328 329if.end:330 %1 = load i32, ptr %arrayidx5, align 4331 %cmp6 = icmp eq i32 %1, %j.017332 br i1 %cmp6, label %for.inc, label %if.end8333; CHECK: edge %if.end -> %for.inc probability is 0x40000000 / 0x80000000 = 50.00%334; CHECK: edge %if.end -> %if.end8 probability is 0x40000000 / 0x80000000 = 50.00%335 336if.end8:337 %2 = load i32, ptr %arrayidx9, align 4338 %cmp10 = icmp eq i32 %2, %j.017339 br i1 %cmp10, label %for.inc, label %if.end12340; CHECK: edge %if.end8 -> %for.inc probability is 0x40000000 / 0x80000000 = 50.00%341; CHECK: edge %if.end8 -> %if.end12 probability is 0x40000000 / 0x80000000 = 50.00%342 343if.end12:344 call void @g2()345 br label %for.inc346; CHECK: edge %if.end12 -> %for.inc probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]347 348for.inc:349 %inc = add nsw i32 %j.017, 1350 %exitcond = icmp eq i32 %inc, %b351 br i1 %exitcond, label %for.end, label %for.body3352; CHECK: edge %for.inc -> %for.end probability is 0x04000000 / 0x80000000 = 3.12%353; CHECK: edge %for.inc -> %for.body3 probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]354 355for.end:356 call void @g3()357 %inc14 = add nsw i32 %i.019, 1358 %exitcond20 = icmp eq i32 %inc14, %a359 br i1 %exitcond20, label %for.end15, label %for.body360; CHECK: edge %for.end -> %for.end15 probability is 0x04000000 / 0x80000000 = 3.12%361; CHECK: edge %for.end -> %for.body probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]362 363for.end15:364 call void @g4()365 ret void366}367 368; Test that an irreducible loop gets heavily weighted back-edges.369define void @test9(i32 %i, i32 %x, i32 %c) {370entry:371 %tobool = icmp eq i32 %c, 0372 br i1 %tobool, label %if.end, label %midloop373; CHECK: edge %entry -> %if.end probability is 0x30000000 / 0x80000000 = 37.50%374; CHECK: edge %entry -> %midloop probability is 0x50000000 / 0x80000000 = 62.50%375 376if.end:377 br label %for.cond378; CHECK: edge %if.end -> %for.cond probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]379 380for.cond:381 %i.addr.0 = phi i32 [ %inc, %for.inc ], [ 0, %if.end ]382 %cmp = icmp slt i32 %i.addr.0, %x383 br i1 %cmp, label %midloop, label %end384; CHECK: edge %for.cond -> %midloop probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]385; CHECK: edge %for.cond -> %end probability is 0x04000000 / 0x80000000 = 3.12%386 387midloop:388 %i.addr.1 = phi i32 [ %i, %entry ], [ %i.addr.0, %for.cond ]389 %call1 = call i32 @g5()390 %tobool2 = icmp eq i32 %call1, 0391 br i1 %tobool2, label %for.inc, label %end392; CHECK: edge %midloop -> %for.inc probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]393; CHECK: edge %midloop -> %end probability is 0x04000000 / 0x80000000 = 3.12%394 395for.inc:396 %inc = add nsw i32 %i.addr.1, 1397 br label %for.cond398; CHECK: edge %for.inc -> %for.cond probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]399 400end:401 ret void402}403 404; Check that the for.body -> if.then edge is considered unlikely due to making405; the if-condition false for the next iteration of the loop.406define i32 @test10(i32 %n, ptr %p) {407entry:408 br label %for.cond409; CHECK: edge %entry -> %for.cond probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]410 411for.cond:412 %count.0 = phi i32 [ 0, %entry ], [ %count.1, %for.inc ]413 %sum.0 = phi i32 [ 0, %entry ], [ %sum.1, %for.inc ]414 %i.0 = phi i32 [ 0, %entry ], [ %inc3, %for.inc ]415 %cmp = icmp slt i32 %i.0, %n416 br i1 %cmp, label %for.body, label %for.cond.cleanup417; CHECK: edge %for.cond -> %for.body probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]418; CHECK: edge %for.cond -> %for.cond.cleanup probability is 0x04000000 / 0x80000000 = 3.12%419 420for.cond.cleanup:421 ret i32 %sum.0422 423for.body:424 %arrayidx = getelementptr inbounds i32, ptr %p, i32 %i.0425 %0 = load i32, ptr %arrayidx, align 4426 %add = add nsw i32 %sum.0, %0427 %inc = add nsw i32 %count.0, 1428 %cmp1 = icmp sgt i32 %count.0, 6429 br i1 %cmp1, label %if.then, label %for.inc430; CHECK: edge %for.body -> %if.then probability is 0x2aaaa8e4 / 0x80000000 = 33.33%431; CHECK: edge %for.body -> %for.inc probability is 0x5555571c / 0x80000000 = 66.67%432if.then:433 store i32 %add, ptr %arrayidx, align 4434 br label %for.inc435; CHECK: edge %if.then -> %for.inc probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]436 437for.inc:438 %count.1 = phi i32 [ 0, %if.then ], [ %inc, %for.body ]439 %sum.1 = phi i32 [ 0, %if.then ], [ %add, %for.body ]440 %inc3 = add nsw i32 %i.0, 1441 br label %for.cond442; CHECK: edge %for.inc -> %for.cond probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]443}444 445; Each successor to for.body makes itself not be taken in the next iteration, so446; both should be equally likely447define i32 @test11(i32 %n, ptr %p) {448entry:449 br label %for.cond450; CHECK: edge %entry -> %for.cond probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]451 452for.cond:453 %flip.0 = phi i32 [ 0, %entry ], [ %flip.1, %for.inc ]454 %sum.0 = phi i32 [ 0, %entry ], [ %sum.1, %for.inc ]455 %i.0 = phi i32 [ 0, %entry ], [ %inc, %for.inc ]456 %cmp = icmp slt i32 %i.0, %n457 br i1 %cmp, label %for.body, label %for.cond.cleanup458; CHECK: edge %for.cond -> %for.body probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]459; CHECK: edge %for.cond -> %for.cond.cleanup probability is 0x04000000 / 0x80000000 = 3.12%460 461for.cond.cleanup:462 ret i32 %sum.0463 464for.body:465 %tobool = icmp eq i32 %flip.0, 0466 %arrayidx1 = getelementptr inbounds i32, ptr %p, i32 %i.0467 %0 = load i32, ptr %arrayidx1, align 4468 br i1 %tobool, label %if.else, label %if.then469; CHECK: edge %for.body -> %if.else probability is 0x40000000 / 0x80000000 = 50.00%470; CHECK: edge %for.body -> %if.then probability is 0x40000000 / 0x80000000 = 50.00%471 472if.then:473 %add = add nsw i32 %0, %sum.0474 store i32 %add, ptr %arrayidx1, align 4475 br label %for.inc476; CHECK: edge %if.then -> %for.inc probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]477 478if.else:479 %add2 = add nsw i32 %sum.0, %0480 br label %for.inc481; CHECK: edge %if.else -> %for.inc probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]482 483for.inc:484 %flip.1 = phi i32 [ 0, %if.then ], [ 1, %if.else ]485 %sum.1 = phi i32 [ %sum.0, %if.then ], [ %add2, %if.else ]486 %inc = add nsw i32 %i.0, 1487 br label %for.cond488; CHECK: edge %for.inc -> %for.cond probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]489}490 491; The loop heuristic should not overwrite the invoke heuristic. The unwind destination492; of an invoke should be considered VERY rare even in a loop.493define void @test12(i32 %a) personality i8 0 {494entry:495 br label %loop496; CHECK: edge %entry -> %loop probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]497 498loop:499 %i.0 = phi i32 [ 0, %entry ], [ %inc, %invoke.cont ]500 invoke i32 @InvokeCall()501 to label %invoke.cont unwind label %lpad502; CHECK: edge %loop -> %invoke.cont probability is 0x7ffff800 / 0x80000000 = 100.00% [HOT edge]503; CHECK: edge %loop -> %lpad probability is 0x00000800 / 0x80000000 = 0.00%504 505invoke.cont:506 %inc = add nsw i32 %i.0, 1507 %cmp = icmp slt i32 %inc, %a508 br i1 %cmp, label %loop, label %exit509; CHECK: edge %invoke.cont -> %loop probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]510; CHECK: edge %invoke.cont -> %exit probability is 0x04000000 / 0x80000000 = 3.12%511 512lpad:513 %ll = landingpad { ptr, i32 }514 cleanup515 br label %exit516 517exit:518 ret void519}520 521declare i32 @InvokeCall()522declare void @cold() cold523 524; If loop has single exit and it leads to 'cold' block then edge leading to loop enter525; should be considered 'cold' as well.526define void @test13(i1 %arg) {527; CHECK: edge %entry -> %loop probability is 0x078780e3 / 0x80000000 = 5.88%528; CHECK: edge %entry -> %exit probability is 0x78787f1d / 0x80000000 = 94.12% [HOT edge]529; CHECK: edge %loop -> %loop probability is 0x7fbe1203 / 0x80000000 = 99.80% [HOT edge]530; CHECK: edge %loop -> %cold probability is 0x0041edfd / 0x80000000 = 0.20%531; CHECK: edge %cold -> %exit probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]532 533entry:534 br i1 %arg, label %loop, label %exit535 536loop:537 %i.0 = phi i32 [ 0, %entry ], [ %inc, %loop ]538 %inc = add nsw i32 %i.0, 1539 br i1 %arg, label %loop, label %cold540 541cold:542 call void @cold()543 br label %exit544 545exit:546 ret void547}548 549; This is the same case as test13 but with additional loop 'preheader' block.550define void @test14(i1 %arg) {551; CHECK: edge %entry -> %preheader probability is 0x078780e3 / 0x80000000 = 5.88%552; CHECK: edge %entry -> %exit probability is 0x78787f1d / 0x80000000 = 94.12% [HOT edge]553; CHECK: edge %preheader -> %loop probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]554; CHECK: edge %loop -> %loop probability is 0x7fbe1203 / 0x80000000 = 99.80% [HOT edge]555; CHECK: edge %loop -> %cold probability is 0x0041edfd / 0x80000000 = 0.20%556; CHECK: edge %cold -> %exit probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]557 558entry:559 br i1 %arg, label %preheader, label %exit560 561preheader:562 br label %loop563 564loop:565 %i.0 = phi i32 [ 0, %preheader ], [ %inc, %loop ]566 %inc = add nsw i32 %i.0, 1567 br i1 %arg, label %loop, label %cold568 569cold:570 call void @cold()571 br label %exit572 573exit:574 ret void575}576 577; If loop has multiple low probability exits then edge leading to loop enter578; should be considered low probable as well.579define void @test15(i1 %arg) {580; CHECK: edge %entry -> %loop probability is 0x078780e3 / 0x80000000 = 5.88%581; CHECK: edge %entry -> %exit probability is 0x78787f1d / 0x80000000 = 94.12% [HOT edge]582; CHECK: edge %loop -> %cont probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]583; CHECK: edge %loop -> %unreached probability is 0x00000000 / 0x80000000 = 0.00%584; CHECK: edge %cont -> %loop probability is 0x7fbe1203 / 0x80000000 = 99.80% [HOT edge]585; CHECK: edge %cont -> %cold probability is 0x0041edfd / 0x80000000 = 0.20%586; CHECK: edge %cold -> %exit probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]587 588entry:589 br i1 %arg, label %loop, label %exit590 591loop:592 %i.0 = phi i32 [ 0, %entry ], [ %inc, %cont ]593 %inc = add nsw i32 %i.0, 1594 br i1 %arg, label %cont, label %unreached595 596cont:597 br i1 %arg, label %loop, label %cold598 599unreached:600 unreachable601 602 603cold:604 call void @cold()605 br label %exit606 607exit:608 ret void609}610 611; This is the same case as test15 but with additional loop 'preheader' block.612define void @test16(i1 %arg) {613; CHECK: edge %entry -> %preheader probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]614; CHECK: edge %preheader -> %loop probability is 0x078780e3 / 0x80000000 = 5.88%615; CHECK: edge %preheader -> %exit probability is 0x78787f1d / 0x80000000 = 94.12% [HOT edge]616; CHECK: edge %loop -> %cont probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]617; CHECK: edge %loop -> %unreached probability is 0x00000000 / 0x80000000 = 0.00%618; CHECK: edge %cont -> %loop probability is 0x7fbe1203 / 0x80000000 = 99.80% [HOT edge]619; CHECK: edge %cont -> %cold probability is 0x0041edfd / 0x80000000 = 0.20%620; CHECK: edge %cold -> %exit probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]621 622entry:623 br label %preheader624 625preheader:626 br i1 %arg, label %loop, label %exit627 628loop:629 %i.0 = phi i32 [ 0, %preheader ], [ %inc, %cont ]630 %inc = add nsw i32 %i.0, 1631 br i1 %arg, label %cont, label %unreached632 633cont:634 br i1 %arg, label %loop, label %cold635 636unreached:637 unreachable638 639 640cold:641 call void @cold()642 br label %exit643 644exit:645 ret void646}647 648declare void @abort() noreturn649 650; Check that 'preheader' has 50/50 probability since there is one 'normal' exit.651; Check that exit to 'cold' and 'noreturn' has lower probability than 'normal' exit.652define void @test17(i1 %arg) {653; CHECK: edge %entry -> %preheader probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]654; CHECK: edge %preheader -> %loop probability is 0x40000000 / 0x80000000 = 50.00%655; CHECK: edge %preheader -> %exit probability is 0x40000000 / 0x80000000 = 50.00%656; CHECK: edge %loop -> %cont probability is 0x7ffff800 / 0x80000000 = 100.00% [HOT edge]657; CHECK: edge %loop -> %noreturn probability is 0x00000800 / 0x80000000 = 0.00%658; CHECK: edge %cont -> %cont2 probability is 0x7fbe1203 / 0x80000000 = 99.80% [HOT edge]659; CHECK: edge %cont -> %cold probability is 0x0041edfd / 0x80000000 = 0.20%660; CHECK: edge %cont2 -> %loop probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]661; CHECK: edge %cont2 -> %exit probability is 0x04000000 / 0x80000000 = 3.12%662; CHECK: edge %cold -> %exit probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]663entry:664 br label %preheader665 666preheader:667 br i1 %arg, label %loop, label %exit668 669loop:670 %i.0 = phi i32 [ 0, %preheader ], [ %inc, %cont2 ]671 %inc = add nsw i32 %i.0, 1672 br i1 %arg, label %cont, label %noreturn673 674cont:675 br i1 %arg, label %cont2, label %cold676 677cont2:678 br i1 %arg, label %loop, label %exit679 680noreturn:681 call void @abort()682 unreachable683 684cold:685 call void @cold()686 br label %exit687 688exit:689 ret void690}691 692 693; This is case with two loops where one nested into another. Nested loop has694; low probable exit what encreases robability to take exit in the top level loop.695define void @test18(i1 %arg) {696; CHECK: edge %entry -> %top.loop probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]697; CHECK: edge %top.loop -> %loop probability is 0x546cd4b7 / 0x80000000 = 65.96%698; CHECK: edge %top.loop -> %exit probability is 0x2b932b49 / 0x80000000 = 34.04%699; CHECK: edge %loop -> %loop probability is 0x7fbe1203 / 0x80000000 = 99.80% [HOT edge]700; CHECK: edge %loop -> %cold probability is 0x0041edfd / 0x80000000 = 0.20%701; CHECK: edge %cold -> %top.loop probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]702 703entry:704 br label %top.loop 705 706top.loop:707 %j.0 = phi i32 [ 0, %entry ], [ %j.inc, %cold ]708 br i1 %arg, label %loop, label %exit709 710loop:711 %i.0 = phi i32 [ %j.0, %top.loop ], [ %inc, %loop ]712 %inc = add nsw i32 %i.0, 1713 br i1 %arg, label %loop, label %cold714 715cold:716 call void @cold()717 %j.inc = add nsw i32 %j.0, 1718 br label %top.loop719 720exit:721 ret void722}723 724 725 726