Index: llvm/lib/CodeGen/LiveDebugValues.cpp =================================================================== --- llvm/lib/CodeGen/LiveDebugValues.cpp +++ llvm/lib/CodeGen/LiveDebugValues.cpp @@ -922,6 +922,12 @@ void LiveDebugValues::transferRegisterDef( MachineInstr &MI, OpenRangesSet &OpenRanges, VarLocMap &VarLocIDs, TransferMap &Transfers) { + + // Meta Instructions do not affect the debug liveness of any register they + // define. + if (MI.isMetaInstruction()) + return; + MachineFunction *MF = MI.getMF(); const TargetLowering *TLI = MF->getSubtarget().getTargetLowering(); unsigned SP = TLI->getStackPointerRegisterToSaveRestore(); Index: llvm/test/DebugInfo/MIR/X86/entry-value-of-modified-param.mir =================================================================== --- llvm/test/DebugInfo/MIR/X86/entry-value-of-modified-param.mir +++ llvm/test/DebugInfo/MIR/X86/entry-value-of-modified-param.mir @@ -103,7 +103,7 @@ CFI_INSTRUCTION offset $rbx, -16 $ebx = MOV32rr $esi DBG_VALUE $ebx, $noreg, !17, !DIExpression(), debug-location !20 - renamable $edi = KILL $edi, implicit-def $rdi + $edi = MOV32ri 5, debug-location !22 DBG_VALUE $edi, $noreg, !16, !DIExpression(), debug-location !20 renamable $edx = LEA64_32r killed renamable $rdi, 1, $noreg, 2, $noreg, debug-location !21 DBG_VALUE $edx, $noreg, !19, !DIExpression(), debug-location !20 Index: llvm/test/DebugInfo/MIR/X86/livedebugvalues-ignores-metaInstructions.mir =================================================================== --- /dev/null +++ llvm/test/DebugInfo/MIR/X86/livedebugvalues-ignores-metaInstructions.mir @@ -0,0 +1,64 @@ +--- | + ; RUN: llc %s -march=x86-64 -run-pass=livedebugvalues -o - | FileCheck %s -implicit-check-not=DBG_VALUE + + ; Check that live-debug-values ignores meta instructions. + + ; CHECK-LABEL: bb.0.entry: + ; CHECK: DBG_VALUE $ebx, $noreg, !16, !DIExpression(), debug-location !17 + ; CHECK-LABEL: bb.1.bb1: + ; CHECK: DBG_VALUE $ebx, $noreg, !16, !DIExpression(), debug-location !17 + ; CHECK-LABEL: bb.2.bb2: + ; CHECK: DBG_VALUE $ebx, $noreg, !16, !DIExpression(), debug-location !17 + ; CHECK-LABEL: bb.3.bb3: + ; CHECK: DBG_VALUE $ebx, $noreg, !16, !DIExpression(), debug-location !17 + + define i32 @_Z8bb_to_bb() local_unnamed_addr !dbg !12 { + entry: + br label %bb1, !dbg !17 + bb1: + br label %bb2, !dbg !17 + bb2: + br label %bb3, !dbg !17 + bb3: + ret i32 0, !dbg !17 + } + + !llvm.dbg.cu = !{!0} + !llvm.module.flags = !{!7, !8, !9, !10} + !llvm.ident = !{!11} + !0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !1, producer: "clang version 10.0.0", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, globals: !3, debugInfoForProfiling: true, nameTableKind: None) + !1 = !DIFile(filename: "main.cpp", directory: "F:\") + !2 = !{} + !3 = !{!4} + !4 = !DIGlobalVariableExpression(var: !5, expr: !DIExpression()) + !5 = distinct !DIGlobalVariable(name: "start", scope: !0, file: !1, line: 4, type: !6, isLocal: false, isDefinition: true) + !6 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed) + !7 = !{i32 2, !"Dwarf Version", i32 4} + !8 = !{i32 2, !"Debug Info Version", i32 3} + !9 = !{i32 1, !"wchar_size", i32 2} + !10 = !{i32 7, !"PIC Level", i32 2} + !11 = !{!"clang version 10.0.0"} + !12 = distinct !DISubprogram(name: "bb_to_bb", linkageName: "bb_to_bb", scope: !1, file: !1, line: 6, type: !13, scopeLine: 6, flags: DIFlagPrototyped, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !15) + !13 = !DISubroutineType(types: !14) + !14 = !{!6, !6} + !15 = !{!16} + !16 = !DILocalVariable(name: "myVar", scope: !12, file: !1, line: 7, type: !6) + !17 = !DILocation(line: 10, scope: !12) + +... +--- +name: _Z8bb_to_bb +body: | + bb.0.entry: + successors: %bb.1 + $ebx = MOV32ri 0, debug-location !17 + DBG_VALUE $ebx, $noreg, !16, !DIExpression(), debug-location !17 + bb.1.bb1: + successors: %bb.2 + renamable $ebx = KILL $ebx + bb.2.bb2: + successors: %bb.3 + renamable $ebx = KILL $ebx + bb.3.bb3: + RETQ $eax, debug-location !17 +...