Rely on a single DWARF version instead of having two copies

This patch makes AsmPrinter less reliant on DwarfDebug by relying on the DWARF version in the AsmPrinter's MCStreamer's MCContext. This allows us to remove the redundant DWARF version from DwarfDebug. It also lets us change code that used to access the AsmPrinter's DwarfDebug just to get to the DWARF version by changing the DWARF version accessor on AsmPrinter so that it grabs the version from its MCStreamer's MCContext.

Differential Revision: https://reviews.llvm.org/D27032

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@287839 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/include/llvm/CodeGen/AsmPrinter.h b/include/llvm/CodeGen/AsmPrinter.h
index dd38979c8246711ab0ea902b45d43e5103381d7e..93c39819061137a3815aa88ea817fdb712076b52 100644 (file)
--- a/include/llvm/CodeGen/AsmPrinter.h
+++ b/include/llvm/CodeGen/AsmPrinter.h
@@ -149,6 +149,9 @@ public:
   DwarfDebug *getDwarfDebug() { return DD; }
   DwarfDebug *getDwarfDebug() const { return DD; }
 
+  uint16_t getDwarfVersion() const;
+  void setDwarfVersion(uint16_t Version);
+
   bool isPositionIndependent() const;
 
   /// Return true if assembly output should contain comments.

diff --git a/lib/CodeGen/AsmPrinter/AsmPrinter.cpp b/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
index 74724c224c8a64fcf5acfc4402d6a081c61e5d67..7f9dc8379010912b245100011cee4c76fa4a1a43 100644 (file)
--- a/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
+++ b/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
@@ -2620,3 +2620,11 @@ void AsmPrinter::recordSled(MCSymbol *Sled, const MachineInstr &MI,
   Sleds.emplace_back(
     XRayFunctionEntry{ Sled, CurrentFnSym, Kind, AlwaysInstrument, Fn });
 }
+
+uint16_t AsmPrinter::getDwarfVersion() const {
+  return OutStreamer->getContext().getDwarfVersion();
+}
+
+void AsmPrinter::setDwarfVersion(uint16_t Version) {
+  OutStreamer->getContext().setDwarfVersion(Version);
+}

diff --git a/lib/CodeGen/AsmPrinter/AsmPrinterDwarf.cpp b/lib/CodeGen/AsmPrinter/AsmPrinterDwarf.cpp
index a6c6373447bd1171e5f5841cfbcf903ab7766779..7efe74f15a6262ff24593a25861b5b8b0459ec0e 100644 (file)
--- a/lib/CodeGen/AsmPrinter/AsmPrinterDwarf.cpp
+++ b/lib/CodeGen/AsmPrinter/AsmPrinterDwarf.cpp
@@ -177,7 +177,7 @@ void AsmPrinter::emitDwarfStringOffset(DwarfStringPoolEntryRef S) const {
 /// EmitDwarfRegOp - Emit dwarf register operation.
 void AsmPrinter::EmitDwarfRegOp(ByteStreamer &Streamer,
                                 const MachineLocation &MLoc) const {
-  DebugLocDwarfExpression Expr(getDwarfDebug()->getDwarfVersion(), Streamer);
+  DebugLocDwarfExpression Expr(getDwarfVersion(), Streamer);
   const MCRegisterInfo *MRI = MMI->getContext().getRegisterInfo();
   int Reg = MRI->getDwarfRegNum(MLoc.getReg(), false);
   if (Reg < 0) {

diff --git a/lib/CodeGen/AsmPrinter/DIE.cpp b/lib/CodeGen/AsmPrinter/DIE.cpp
index 75b9a1658bdce5bf79fd92706c85052496eb0ad4..afb7e87d36a2b30f27ca2464f758746c02eafd7b 100644 (file)
--- a/lib/CodeGen/AsmPrinter/DIE.cpp
+++ b/lib/CodeGen/AsmPrinter/DIE.cpp
@@ -298,7 +298,7 @@ unsigned DIEInteger::SizeOf(const AsmPrinter *AP, dwarf::Form Form) const {
   case dwarf::DW_FORM_addr:
     return AP->getPointerSize();
   case dwarf::DW_FORM_ref_addr:
-    if (AP->OutStreamer->getContext().getDwarfVersion() == 2)
+    if (AP->getDwarfVersion() == 2)
       return AP->getPointerSize();
     return sizeof(int32_t);
   default: llvm_unreachable("DIE Value form not supported yet");
@@ -466,9 +466,7 @@ unsigned DIEEntry::getRefAddrSize(const AsmPrinter *AP) {
   // specified to be four bytes in the DWARF 32-bit format and eight bytes
   // in the DWARF 64-bit format, while DWARF Version 2 specifies that such
   // references have the same size as an address on the target system.
-  const DwarfDebug *DD = AP->getDwarfDebug();
-  assert(DD && "Expected Dwarf Debug info to be available");
-  if (DD->getDwarfVersion() == 2)
+  if (AP->getDwarfVersion() == 2)
     return AP->getPointerSize();
   return sizeof(int32_t);
 }

diff --git a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
index 06641d807844f589768becfd3611fd66fc9701b9..884e03d3f0a2b601f84b58451f02f9927d213aca 100644 (file)
--- a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
+++ b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
@@ -256,7 +256,7 @@ DwarfDebug::DwarfDebug(AsmPrinter *A, Module *M)
     UseAllLinkageNames = DwarfLinkageNames == AllLinkageNames;
 
   unsigned DwarfVersionNumber = Asm->TM.Options.MCOptions.DwarfVersion;
-  DwarfVersion = DwarfVersionNumber ? DwarfVersionNumber
+  unsigned DwarfVersion = DwarfVersionNumber ? DwarfVersionNumber
                                     : MMI->getModule()->getDwarfVersion();
   // Use dwarf 4 by default if nothing is requested.
   DwarfVersion = DwarfVersion ? DwarfVersion : dwarf::DWARF_VERSION;
@@ -1197,7 +1197,7 @@ void DwarfDebug::recordSourceLine(unsigned Line, unsigned Col, const MDNode *S,
     Fn = Scope->getFilename();
     Dir = Scope->getDirectory();
     if (auto *LBF = dyn_cast<DILexicalBlockFile>(Scope))
-      if (DwarfVersion >= 4)
+      if (getDwarfVersion() >= 4)
         Discriminator = LBF->getDiscriminator();
 
     unsigned CUID = Asm->OutStreamer->getContext().getDwarfCompileUnitID();
@@ -1415,8 +1415,7 @@ static void emitDebugLocValue(const AsmPrinter &AP, const DIBasicType *BT,
                               const DebugLocEntry::Value &Value,
                               unsigned PieceOffsetInBits) {
   DIExpressionCursor ExprCursor(Value.getExpression());
-  DebugLocDwarfExpression DwarfExpr(AP.getDwarfDebug()->getDwarfVersion(),
-                                    Streamer);
+  DebugLocDwarfExpression DwarfExpr(AP.getDwarfVersion(), Streamer);
   // Regular entry.
   if (Value.isInt()) {
     if (BT && (BT->getEncoding() == dwarf::DW_ATE_signed ||
@@ -1467,8 +1466,7 @@ void DebugLocEntry::finalize(const AsmPrinter &AP,
       assert(Offset <= PieceOffset && "overlapping or duplicate pieces");
       if (Offset < PieceOffset) {
         // The DWARF spec seriously mandates pieces with no locations for gaps.
-        DebugLocDwarfExpression Expr(AP.getDwarfDebug()->getDwarfVersion(),
-                                     Streamer);
+        DebugLocDwarfExpression Expr(AP.getDwarfVersion(), Streamer);
         Expr.AddOpPiece(PieceOffset-Offset, 0);
         Offset += PieceOffset-Offset;
       }
@@ -1983,3 +1981,7 @@ void DwarfDebug::addAccelType(StringRef Name, const DIE &Die, char Flags) {
     return;
   AccelTypes.AddName(InfoHolder.getStringPool().getEntry(*Asm, Name), &Die);
 }
+
+uint16_t DwarfDebug::getDwarfVersion() const {
+  return Asm->OutStreamer->getContext().getDwarfVersion();
+}

diff --git a/lib/CodeGen/AsmPrinter/DwarfDebug.h b/lib/CodeGen/AsmPrinter/DwarfDebug.h
index 7d36fe924fd8fa3a392d4db7f8a76316d4793265..37d03a6bf90347a73cb71547a69c79851187ba56 100644 (file)
--- a/lib/CodeGen/AsmPrinter/DwarfDebug.h
+++ b/lib/CodeGen/AsmPrinter/DwarfDebug.h
@@ -254,9 +254,6 @@ class DwarfDebug : public DebugHandlerBase {
   /// Whether to emit all linkage names, or just abstract subprograms.
   bool UseAllLinkageNames;
 
-  /// Version of dwarf we're emitting.
-  unsigned DwarfVersion;
-
   /// DWARF5 Experimental Options
   /// @{
   bool HasDwarfAccelTables;
@@ -515,7 +512,7 @@ public:
   bool useSplitDwarf() const { return HasSplitDwarf; }
 
   /// Returns the Dwarf Version.
-  unsigned getDwarfVersion() const { return DwarfVersion; }
+  uint16_t getDwarfVersion() const;
 
   /// Returns the previous CU that was being updated
   const DwarfCompileUnit *getPrevCU() const { return PrevCU; }

diff --git a/lib/CodeGen/AsmPrinter/DwarfUnit.cpp b/lib/CodeGen/AsmPrinter/DwarfUnit.cpp
index a49518a378f844f983a2ee81e45751964a7833a6..f97b5deb6ccd894b2d1d603cc90196b96a08f1a4 100644 (file)
--- a/lib/CodeGen/AsmPrinter/DwarfUnit.cpp
+++ b/lib/CodeGen/AsmPrinter/DwarfUnit.cpp
@@ -51,7 +51,7 @@ GenerateDwarfTypeUnits("generate-type-units", cl::Hidden,
 
 DIEDwarfExpression::DIEDwarfExpression(const AsmPrinter &AP, DwarfUnit &DU,
                                        DIELoc &DIE)
-    : DwarfExpression(AP.getDwarfDebug()->getDwarfVersion()), AP(AP), DU(DU),
+    : DwarfExpression(AP.getDwarfVersion()), AP(AP), DU(DU),
       DIE(DIE) {}
 
 void DIEDwarfExpression::EmitOp(uint8_t Op, const char* Comment) {