1; RUN: opt -S -passes=instcombine %s | FileCheck %s -check-prefix=RUN-ONCE 2; RUN: opt -S -passes=instcombine %s --try-experimental-debuginfo-iterators | FileCheck %s -check-prefix=RUN-ONCE 3 4; This example was reduced from a test case in which InstCombine ran at least 5; twice: 6; - The first InstCombine run converted dbg.declares to dbg.values using the 7; LowerDbgDeclare utility. This produced a dbg.value(ptr %2, DW_OP_deref) 8; (this happens when the contents of an alloca are passed by-value), and a 9; dbg.value(i32 %0) (due to the store of %0 into the alloca). 10; - The second InstCombine run deleted the alloca (%2). 11; Check that the DW_OP_deref dbg.value is deleted, just like a dbg.declare would 12; be. 13; 14; RUN-ONCE-LABEL: @t1( 15; RUN-ONCE-NEXT: #dbg_value(i32 %0, [[t1_arg0:![0-9]+]], !DIExpression(), 16; RUN-ONCE-NEXT: #dbg_value(ptr poison, [[t1_fake_ptr:![0-9]+]], !DIExpression(), 17; RUN-ONCE-NEXT: ret void 18define void @t1(i32) !dbg !9 { 19 %2 = alloca i32, align 4 20 store i32 %0, ptr %2, align 4 21 call void @llvm.dbg.value(metadata i32 %0, metadata !14, metadata !DIExpression()), !dbg !15 22 call void @llvm.dbg.value(metadata ptr %2, metadata !14, metadata !DIExpression(DW_OP_deref)), !dbg !15 23 call void @llvm.dbg.value(metadata ptr %2, metadata !20, metadata !DIExpression()), !dbg !15 24 ret void 25} 26 27; This example is closer to an end-to-end test: the IR looks like it could have 28; been produced by a frontend compiling at -O0. 29; 30; Here's what happens: 31; 1) We run InstCombine. This puts a dbg.value(ptr %x.addr, DW_OP_deref) 32; before the call to @use, and a dbg.value(i32 %x) after the store. 33; 2) We inline @use. 34; 3) We run InstCombine again. The alloca %x.addr is erased. We should just get 35; dbg.value(i32 %x). There should be no leftover dbg.value(metadata ptr 36; undef). 37; 38;;; define void @use(ptr %addr) alwaysinline { ret void } 39;;; define void @t2(i32 %x) !dbg !17 { 40;;; %x.addr = alloca i32, align 4 41;;; store i32 %x, ptr %x.addr, align 4 42;;; call void @llvm.dbg.declare(metadata ptr %x.addr, metadata !18, metadata !DIExpression()), !dbg !19 43;;; call void @use(ptr %x.addr) 44;;; ret void 45;;; } 46 47declare void @llvm.dbg.value(metadata, metadata, metadata) 48declare void @llvm.dbg.declare(metadata, metadata, metadata) 49 50!llvm.module.flags = !{!0, !1, !2, !3, !4} 51!llvm.dbg.cu = !{!5} 52!llvm.ident = !{!8} 53 54; RUN-ONCE: [[t1_arg0]] = !DILocalVariable(name: "a" 55; RUN-ONCE: [[t1_fake_ptr]] = !DILocalVariable(name: "fake_ptr" 56 57!0 = !{i32 2, !"SDK Version", [2 x i32] [i32 10, i32 14]} 58!1 = !{i32 2, !"Dwarf Version", i32 4} 59!2 = !{i32 2, !"Debug Info Version", i32 3} 60!3 = !{i32 1, !"wchar_size", i32 4} 61!4 = !{i32 7, !"PIC Level", i32 2} 62!5 = distinct !DICompileUnit(language: DW_LANG_C99, file: !6, producer: "", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, enums: !7, nameTableKind: GNU) 63!6 = !DIFile(filename: "-", directory: "/") 64!7 = !{} 65!8 = !{!""} 66!9 = distinct !DISubprogram(name: "t1", scope: !10, file: !10, line: 1, type: !11, scopeLine: 1, flags: DIFlagPrototyped, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !7) 67!10 = !DIFile(filename: "<stdin>", directory: "/") 68!11 = !DISubroutineType(types: !12) 69!12 = !{null, !13} 70!13 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed) 71!14 = !DILocalVariable(name: "a", arg: 1, scope: !9, file: !10, line: 1, type: !13) 72!15 = !DILocation(line: 1, column: 13, scope: !9) 73!16 = !DILocation(line: 1, column: 17, scope: !9) 74!17 = distinct !DISubprogram(name: "t2", scope: !10, file: !10, line: 1, type: !11, scopeLine: 1, flags: DIFlagPrototyped, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !7) 75!18 = !DILocalVariable(name: "x", arg: 1, scope: !17, file: !10, line: 1, type: !13) 76!19 = !DILocation(line: 1, column: 1, scope: !17) 77!20 = !DILocalVariable(name: "fake_ptr", scope: !9, file: !10, line: 1, type: !13) 78