Commit 8703cc62 authored by Bill Wendling's avatar Bill Wendling
Browse files

Merging r182344: 

------------------------------------------------------------------------
r182344 | mren | 2013-05-20 17:57:22 -0700 (Mon, 20 May 2013) | 7 lines

Dwarf: use a single line table to generate assembly when .loc is used.

This is to fix PR15408 where an undefined symbol Lline_table_start1 is used.
Since we do not generate the debug_line section when .loc is used,
Lline_table_start1 is not emitted and we can't refer to it when calculating
at_stmt_list for a compile unit.

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llvm-svn: 182346
parent d3e6cfff

llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp

+14 −3
Original line number Diff line number Diff line
@@ -708,6 +708,12 @@ CompileUnit *DwarfDebug::constructCompileUnit(const MDNode *N) { 
  Asm->OutStreamer.getContext().setMCLineTableSymbol(LineTableStartSym,

                                                     NewCU->getUniqueID());



  // Use a single line table if we are using .loc and generating assembly.

  bool UseTheFirstCU =

    (Asm->TM.hasMCUseLoc() &&

     Asm->OutStreamer.getKind() == MCStreamer::SK_AsmStreamer) ||

    (NewCU->getUniqueID() == 0);



  // DW_AT_stmt_list is a offset of line number information for this

  // compile unit in debug_line section. For split dwarf this is

  // left in the skeleton CU and so not included.
@@ -716,9 +722,9 @@ CompileUnit *DwarfDebug::constructCompileUnit(const MDNode *N) { 
  if (!useSplitDwarf()) {

    if (Asm->MAI->doesDwarfUseRelocationsAcrossSections())

      NewCU->addLabel(Die, dwarf::DW_AT_stmt_list, dwarf::DW_FORM_data4,

                      NewCU->getUniqueID() == 0 ?

                      UseTheFirstCU ?

                      Asm->GetTempSymbol("section_line") : LineTableStartSym);

    else if (NewCU->getUniqueID() == 0)

    else if (UseTheFirstCU)

      NewCU->addUInt(Die, dwarf::DW_AT_stmt_list, dwarf::DW_FORM_data4, 0);

    else

      NewCU->addDelta(Die, dwarf::DW_AT_stmt_list, dwarf::DW_FORM_data4,
@@ -1441,6 +1447,11 @@ void DwarfDebug::beginFunction(const MachineFunction *MF) { 
  LexicalScope *FnScope = LScopes.getCurrentFunctionScope();

  CompileUnit *TheCU = SPMap.lookup(FnScope->getScopeNode());

  assert(TheCU && "Unable to find compile unit!");

  if (Asm->TM.hasMCUseLoc() &&

      Asm->OutStreamer.getKind() == MCStreamer::SK_AsmStreamer)

    // Use a single line table if we are using .loc and generating assembly.

    Asm->OutStreamer.getContext().setDwarfCompileUnitID(0);

  else

    Asm->OutStreamer.getContext().setDwarfCompileUnitID(TheCU->getUniqueID());



  FunctionBeginSym = Asm->GetTempSymbol("func_begin",

llvm/test/DebugInfo/X86/stmt-list-multiple-compile-units.ll

+6 −0
Original line number Diff line number Diff line 
; RUN: llc -O0 %s -mtriple=x86_64-apple-darwin -filetype=obj -o %t

; RUN: llvm-dwarfdump %t | FileCheck %s

; RUN: llc < %s -O0 -mtriple=x86_64-apple-macosx10.7 | FileCheck %s -check-prefix=ASM



; rdar://13067005

; CHECK: .debug_info contents:
@@ -20,6 +21,11 @@ 
; CHECK: file_names[  1]    0 0x00000000 0x00000000 simple2.c

; CHECK-NOT: file_names



; PR15408

; ASM: L__DWARF__debug_info_begin0:

; ASM: .long   0                       ## DW_AT_stmt_list

; ASM: L__DWARF__debug_info_begin1:

; ASM: .long   0                       ## DW_AT_stmt_list

define i32 @test(i32 %a) nounwind uwtable ssp {

entry:

  %a.addr = alloca i32, align 4