1; RUN: opt -enable-new-pm=1 -sample-profile -licm -S -sample-profile-file='%S/Inputs/no-hoist-prof.prof' < %s | FileCheck %s --check-prefix=CHECK-BFI-LICM 2; RUN: opt -passes=licm -S < %s | FileCheck %s --check-prefix=CHECK-LICM 3 4; Original source code: 5; 6; int bar(int); 7; int foo(int iter, int explode) { 8; int base = bar(explode); 9; for (int i = 0; i != iter; ++i) 10; if (i == explode) 11; iter = (base * base) + bar(iter); 12; return iter; 13; } 14 15; We need debug information in this .ll in order to leverage the pgo file, so: 16; .ll generated by running `clang++ -O3 -g -S -emit-llvm`, then: 17; - move hoisted mul back into cold section 18; - give labels names 19; - reindex variables 20; - remove metadata calls, attributes, module header 21; - remove unnecessary metadata 22 23; CHECK-LICM: .l.check.preheader:{{.*}} 24; CHECK-LICM-NEXT: {{.*}} = mul {{.*}} 25; CHECK-LICM-NEXT: br{{.*}} 26 27; CHECK-BFI-LICM: .l.cold:{{.*}} 28; CHECK-BFI-LICM-NEXT: {{.*}} = mul {{.*}} 29 30define dso_local i32 @_Z3fooii(i32, i32) local_unnamed_addr #0 !dbg !7 { 31 %3 = tail call i32 @_Z3bari(i32 %1), !dbg !19 32 %4 = icmp eq i32 %0, 0, !dbg !22 33 br i1 %4, label %.l.ret, label %.l.check.preheader, !dbg !24 34 35.l.check.preheader: 36 br label %.l.check, !dbg !24 37 38.l.ret: 39 %5 = phi i32 [ 0, %2 ], [ %12, %.l.iterate ] 40 ret i32 %5, !dbg !25 41 42.l.check: 43 %6 = phi i32 [ 0, %.l.check.preheader ], [ %13, %.l.iterate ] 44 %7 = phi i32 [ %0, %.l.check.preheader ], [ %12, %.l.iterate ] 45 %8 = icmp eq i32 %6, %1, !dbg !26 46 br i1 %8, label %.l.cold, label %.l.iterate, !dbg !28 47 48.l.cold: 49 %9 = mul nsw i32 %3, %3 50 %10 = tail call i32 @_Z3bari(i32 %7), !dbg !29 51 %11 = add nsw i32 %10, %9, !dbg !30 52 br label %.l.iterate, !dbg !31 53 54.l.iterate: 55 %12 = phi i32 [ %11, %.l.cold ], [ %7, %.l.check ] 56 %13 = add nuw nsw i32 %6, 1, !dbg !32 57 %14 = icmp eq i32 %13, %12, !dbg !22 58 br i1 %14, label %.l.ret, label %.l.check, !dbg !24, !llvm.loop !33 59} 60 61attributes #0 = { "use-sample-profile" } 62 63declare dso_local i32 @_Z3bari(i32) local_unnamed_addr #1 64 65!llvm.module.flags = !{!4} 66 67!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !1, producer: "clang version 8.0.20181009 ", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, nameTableKind: None) 68!1 = !DIFile(filename: "foo.cpp", directory: "/tmp/gather_pgo") 69!4 = !{i32 2, !"Debug Info Version", i32 3} 70!7 = distinct !DISubprogram(name: "foo", linkageName: "_Z3fooii", scope: !1, file: !1, line: 2, type: !8, isLocal: false, isDefinition: true, scopeLine: 2, flags: DIFlagPrototyped, isOptimized: true, unit: !0) 71!8 = !DISubroutineType(types: !9) 72!9 = !{!10, !10, !10} 73!10 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed) 74!16 = distinct !DILexicalBlock(scope: !7, file: !1, line: 4, column: 3) 75!19 = !DILocation(line: 3, column: 14, scope: !7) 76!22 = !DILocation(line: 4, column: 21, scope: !23) 77!23 = distinct !DILexicalBlock(scope: !16, file: !1, line: 4, column: 3) 78!24 = !DILocation(line: 4, column: 3, scope: !16) 79!25 = !DILocation(line: 7, column: 3, scope: !7) 80!26 = !DILocation(line: 5, column: 11, scope: !27) 81!27 = distinct !DILexicalBlock(scope: !23, file: !1, line: 5, column: 9) 82!28 = !DILocation(line: 5, column: 9, scope: !23) 83!29 = !DILocation(line: 6, column: 30, scope: !27) 84!30 = !DILocation(line: 6, column: 28, scope: !27) 85!31 = !DILocation(line: 6, column: 7, scope: !27) 86!32 = !DILocation(line: 4, column: 30, scope: !23) 87!33 = distinct !{!33, !24, !34} 88!34 = !DILocation(line: 6, column: 38, scope: !16) 89