From 0493f95a2cc8f4faea3df1b97d613ae87c670153 Mon Sep 17 00:00:00 2001
From: Devang Patel <dpatel@apple.com>
Date: Mon, 22 Mar 2010 22:38:48 +0000
Subject: [PATCH] DW_AT_stmt_list attribute attached with a compile unit
 encodes offset of line number information for this compile unit in debug_line
 section. This offset is always zero when only one compile unit is emitted in
 a object file.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@99223 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/CodeGen/AsmPrinter/DIE.cpp        | 25 ---------------------
 lib/CodeGen/AsmPrinter/DIE.h          | 32 ---------------------------
 lib/CodeGen/AsmPrinter/DwarfDebug.cpp | 18 ++++-----------
 lib/CodeGen/AsmPrinter/DwarfDebug.h   |  6 -----
 4 files changed, 4 insertions(+), 77 deletions(-)

diff --git a/lib/CodeGen/AsmPrinter/DIE.cpp b/lib/CodeGen/AsmPrinter/DIE.cpp
index 141c80b38ef..cb2fe472fb6 100644
--- a/lib/CodeGen/AsmPrinter/DIE.cpp
+++ b/lib/CodeGen/AsmPrinter/DIE.cpp
@@ -277,31 +277,6 @@ void DIELabel::print(raw_ostream &O) {
 }
 #endif
 
-//===----------------------------------------------------------------------===//
-// DIESectionOffset Implementation
-//===----------------------------------------------------------------------===//
-
-/// EmitValue - Emit delta value.
-///
-void DIESectionOffset::EmitValue(DwarfPrinter *D, unsigned Form) const {
-  bool IsSmall = Form == dwarf::DW_FORM_data4;
-  D->EmitSectionOffset(Label, Section, IsSmall, IsEH);
-}
-
-/// SizeOf - Determine size of delta value in bytes.
-///
-unsigned DIESectionOffset::SizeOf(const TargetData *TD, unsigned Form) const {
-  if (Form == dwarf::DW_FORM_data4) return 4;
-  return TD->getPointerSize();
-}
-
-#ifndef NDEBUG
-void DIESectionOffset::print(raw_ostream &O) {
-  O << "Off: " << Label->getName() << "-" << Section->getName()
-    << "-" << IsEH;
-}
-#endif
-
 //===----------------------------------------------------------------------===//
 // DIEDelta Implementation
 //===----------------------------------------------------------------------===//
diff --git a/lib/CodeGen/AsmPrinter/DIE.h b/lib/CodeGen/AsmPrinter/DIE.h
index 1a41e2829c2..4ba40aa1faf 100644
--- a/lib/CodeGen/AsmPrinter/DIE.h
+++ b/lib/CodeGen/AsmPrinter/DIE.h
@@ -324,38 +324,6 @@ namespace llvm {
     static bool classof(const DIELabel *)  { return true; }
     static bool classof(const DIEValue *L) { return L->getType() == isLabel; }
 
-#ifndef NDEBUG
-    virtual void print(raw_ostream &O);
-#endif
-  };
-
-  //===--------------------------------------------------------------------===//
-  /// DIESectionOffset - A section offset DIE.
-  ///
-  class DIESectionOffset : public DIEValue {
-    const MCSymbol *Label;
-    const MCSymbol *Section;
-    bool IsEH : 1;
-  public:
-    DIESectionOffset(const MCSymbol *Lab, const MCSymbol *Sec,
-                     bool isEH = false)
-      : DIEValue(isSectionOffset), Label(Lab), Section(Sec),
-        IsEH(isEH) {}
-
-    /// EmitValue - Emit section offset.
-    ///
-    virtual void EmitValue(DwarfPrinter *D, unsigned Form) const;
-
-    /// SizeOf - Determine size of section offset value in bytes.
-    ///
-    virtual unsigned SizeOf(const TargetData *TD, unsigned Form) const;
-
-    // Implement isa/cast/dyncast.
-    static bool classof(const DIESectionOffset *)  { return true; }
-    static bool classof(const DIEValue *D) {
-      return D->getType() == isSectionOffset;
-    }
-
 #ifndef NDEBUG
     virtual void print(raw_ostream &O);
 #endif
diff --git a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
index c935d3a3312..83cac7916b4 100644
--- a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
+++ b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
@@ -386,16 +386,6 @@ void DwarfDebug::addLabel(DIE *Die, unsigned Attribute, unsigned Form,
   Die->addValue(Attribute, Form, Value);
 }
 
-/// addSectionOffset - Add a section offset label attribute data and value.
-///
-void DwarfDebug::addSectionOffset(DIE *Die, unsigned Attribute, unsigned Form,
-                                  const MCSymbol *Label,const MCSymbol *Section,
-                                  bool isEH) {
-  DIEValue *Value = new DIESectionOffset(Label, Section, isEH);
-  DIEValues.push_back(Value);
-  Die->addValue(Attribute, Form, Value);
-}
-
 /// addDelta - Add a label delta attribute data and value.
 ///
 void DwarfDebug::addDelta(DIE *Die, unsigned Attribute, unsigned Form,
@@ -1666,10 +1656,10 @@ void DwarfDebug::constructCompileUnit(MDNode *N) {
   unsigned ID = GetOrCreateSourceID(Dir, FN);
 
   DIE *Die = new DIE(dwarf::DW_TAG_compile_unit);
-  // FIXME: Why getting the delta between two identical labels??
-  addSectionOffset(Die, dwarf::DW_AT_stmt_list, dwarf::DW_FORM_data4,
-                   getTempLabel("section_line"), getTempLabel("section_line"),
-                   false);
+  // DW_AT_stmt_list is a offset of line number information for this
+  // compile unit in debug_line section. It is always zero when only one
+  // compile unit is emitted in one object file.
+  addUInt(Die, dwarf::DW_AT_stmt_list, dwarf::DW_FORM_data4, 0);
   addString(Die, dwarf::DW_AT_producer, dwarf::DW_FORM_string,
             DIUnit.getProducer());
   addUInt(Die, dwarf::DW_AT_language, dwarf::DW_FORM_data1,
diff --git a/lib/CodeGen/AsmPrinter/DwarfDebug.h b/lib/CodeGen/AsmPrinter/DwarfDebug.h
index d6634e1f5d1..6004bb3510f 100644
--- a/lib/CodeGen/AsmPrinter/DwarfDebug.h
+++ b/lib/CodeGen/AsmPrinter/DwarfDebug.h
@@ -250,12 +250,6 @@ class DwarfDebug : public DwarfPrinter {
   void addLabel(DIE *Die, unsigned Attribute, unsigned Form,
                 const MCSymbol *Label);
 
-  /// addSectionOffset - Add a section offset label attribute data and value.
-  ///
-  void addSectionOffset(DIE *Die, unsigned Attribute, unsigned Form,
-                        const MCSymbol *Label, const MCSymbol *Section,
-                        bool isEH = false);
-
   /// addDelta - Add a label delta attribute data and value.
   ///
   void addDelta(DIE *Die, unsigned Attribute, unsigned Form,
-- 
2.34.1