1; RUN: llc < %s -tail-dup-placement-threshold=4 | FileCheck %s 2 3; Based on test case from PR43695: 4; __declspec(allocator) void *alloc(unsigned int size); 5; void f2(); 6; void f1(unsigned int *size_ptr) { 7; void *hg = alloc(size_ptr ? *size_ptr : 1UL); 8; f2(); 9; } 10 11; In this case, block placement duplicates the heap allocation site. 12 13; ModuleID = 't.cpp' 14source_filename = "t.cpp" 15target datalayout = "e-m:w-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128" 16target triple = "x86_64-pc-windows-msvc19.22.27905" 17 18define dso_local void @taildupit(i32* readonly %size_ptr) !dbg !8 { 19entry: 20 call void @llvm.dbg.value(metadata i32* %size_ptr, metadata !14, metadata !DIExpression()), !dbg !17 21 %tobool = icmp eq i32* %size_ptr, null, !dbg !18 22 br i1 %tobool, label %cond.end, label %cond.true, !dbg !18 23 24cond.true: ; preds = %entry 25 %0 = load i32, i32* %size_ptr, align 4, !dbg !18, !tbaa !19 26 br label %cond.end, !dbg !18 27 28cond.end: ; preds = %entry, %cond.true 29 %cond = phi i32 [ %0, %cond.true ], [ 1, %entry ], !dbg !18 30 %call = tail call i8* @alloc(i32 %cond), !dbg !18, !heapallocsite !2 31 call void @llvm.dbg.value(metadata i8* %call, metadata !15, metadata !DIExpression()), !dbg !17 32 tail call void @f2(), !dbg !23 33 ret void, !dbg !24 34} 35 36; CHECK-LABEL: taildupit: # @taildupit 37; CHECK: testq 38; CHECK: je 39; CHECK: callq alloc 40; CHECK-NEXT: [[L1:.Ltmp[0-9]+]] 41; CHECK: jmp f2 # TAILCALL 42; CHECK: callq alloc 43; CHECK-NEXT: [[L3:.Ltmp[0-9]+]] 44; CHECK: jmp f2 # TAILCALL 45 46; CHECK-LABEL: .short 4423 # Record kind: S_GPROC32_ID 47; CHECK: .short 4446 # Record kind: S_HEAPALLOCSITE 48; CHECK-NEXT: .secrel32 [[L0:.Ltmp[0-9]+]] 49; CHECK-NEXT: .secidx [[L0]] 50; CHECK-NEXT: .short [[L1]]-[[L0]] 51; CHECK-NEXT: .long 3 52; CHECK: .short 4446 # Record kind: S_HEAPALLOCSITE 53; CHECK-NEXT: .secrel32 [[L2:.Ltmp[0-9]+]] 54; CHECK-NEXT: .secidx [[L2]] 55; CHECK-NEXT: .short [[L3]]-[[L2]] 56; CHECK-NEXT: .long 3 57 58declare dso_local i8* @alloc(i32) 59 60declare dso_local void @f2() 61 62declare void @llvm.dbg.value(metadata, metadata, metadata) 63 64!llvm.dbg.cu = !{!0} 65!llvm.module.flags = !{!3, !4, !5, !6} 66 67!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus_14, file: !1, producer: "clang version 10.0.0 (git@github.com:llvm/llvm-project.git 0650355c09ab8e6605ae37b818270a7a7c8ce2c7)", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, nameTableKind: None) 68!1 = !DIFile(filename: "t.cpp", directory: "C:\\src\\llvm-project\\build", checksumkind: CSK_MD5, checksum: "b227901e92d848fa564190b0762d757c") 69!2 = !{} 70!3 = !{i32 2, !"CodeView", i32 1} 71!4 = !{i32 2, !"Debug Info Version", i32 3} 72!5 = !{i32 1, !"wchar_size", i32 2} 73!6 = !{i32 7, !"PIC Level", i32 2} 74!8 = distinct !DISubprogram(name: "f1", linkageName: "?f1@@YAXPEAI@Z", scope: !1, file: !1, line: 5, type: !9, scopeLine: 5, flags: DIFlagPrototyped, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !13) 75!9 = !DISubroutineType(types: !10) 76!10 = !{null, !11} 77!11 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !12, size: 64) 78!12 = !DIBasicType(name: "unsigned int", size: 32, encoding: DW_ATE_unsigned) 79!13 = !{!14, !15} 80!14 = !DILocalVariable(name: "size_ptr", arg: 1, scope: !8, file: !1, line: 5, type: !11) 81!15 = !DILocalVariable(name: "hg", scope: !8, file: !1, line: 6, type: !16) 82!16 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: null, size: 64) 83!17 = !DILocation(line: 0, scope: !8) 84!18 = !DILocation(line: 6, scope: !8) 85!19 = !{!20, !20, i64 0} 86!20 = !{!"int", !21, i64 0} 87!21 = !{!"omnipotent char", !22, i64 0} 88!22 = !{!"Simple C++ TBAA"} 89!23 = !DILocation(line: 7, scope: !8) 90!24 = !DILocation(line: 8, scope: !8) 91