Reland 196270 "Generalize debug info / EH emission in AsmPrinter"

Addressing the existense AMDGPUAsmPrinter and other subclasses of AsmPrinter

llvm-svn: 196288

Author: timurrrr

llvm/include/llvm/CodeGen/AsmPrinter.h

@@ -22,6 +22,7 @@
 #include "llvm/Support/ErrorHandling.h"
 
 namespace llvm {
+  class AsmPrinterHandler;
   class BlockAddress;
   class GCStrategy;
   class Constant;
@@ -110,13 +111,21 @@ namespace llvm {
     /// function.
     MachineLoopInfo *LI;
 
+    struct HandlerInfo {
+      AsmPrinterHandler *Handler;
+      const char *TimerName, *TimerGroupName;
+      HandlerInfo(AsmPrinterHandler *Handler, const char *TimerName,
+                  const char *TimerGroupName)
+          : Handler(Handler), TimerName(TimerName),
+            TimerGroupName(TimerGroupName) {}
+    };
+    /// Handlers - a vector of all debug/EH info emitters we should use.
+    /// This vector maintains ownership of the emitters.
+    SmallVector<HandlerInfo, 1> Handlers;
+
     /// DD - If the target supports dwarf debug info, this pointer is non-null.
     DwarfDebug *DD;
 
-    /// DE - If the target supports dwarf exception info, this pointer is
-    /// non-null.
-    DwarfException *DE;
-
   protected:
     explicit AsmPrinter(TargetMachine &TM, MCStreamer &Streamer);
 

llvm/lib/CodeGen/AsmPrinter/ARMException.cpp

@@ -66,7 +66,7 @@ void ARMException::beginFunction(const MachineFunction *MF) {
 
 /// endFunction - Gather and emit post-function exception information.
 ///
-void ARMException::endFunction() {
+void ARMException::endFunction(const MachineFunction *) {
   ARMTargetStreamer &ATS = getTargetStreamer();
   if (!Asm->MF->getFunction()->needsUnwindTableEntry())
     ATS.emitCantUnwind();

llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp

@@ -99,14 +99,14 @@ AsmPrinter::AsmPrinter(TargetMachine &tm, MCStreamer &Streamer)
     OutContext(Streamer.getContext()),
     OutStreamer(Streamer),
     LastMI(0), LastFn(0), Counter(~0U), SetCounter(0) {
-  DD = 0; DE = 0; MMI = 0; LI = 0; MF = 0;
+  DD = 0; MMI = 0; LI = 0; MF = 0;
   CurrentFnSym = CurrentFnSymForSize = 0;
   GCMetadataPrinters = 0;
   VerboseAsm = Streamer.isVerboseAsm();
 }
 
 AsmPrinter::~AsmPrinter() {
-  assert(DD == 0 && DE == 0 && "Debug/EH info didn't get finalized");
+  assert(DD == 0 && Handlers.empty() && "Debug/EH info didn't get finalized");
 
   if (GCMetadataPrinters != 0) {
     gcp_map_type &GCMap = getGCMap(GCMetadataPrinters);
@@ -192,25 +192,29 @@ bool AsmPrinter::doInitialization(Module &M) {
     OutStreamer.AddBlankLine();
   }
 
-  if (MAI->doesSupportDebugInformation())
+  if (MAI->doesSupportDebugInformation()) {
     DD = new DwarfDebug(this, &M);
+    Handlers.push_back(HandlerInfo(DD, DbgTimerName, DWARFGroupName));
+  }
 
+  DwarfException *DE = 0;
   switch (MAI->getExceptionHandlingType()) {
   case ExceptionHandling::None:
-    return false;
+    break;
   case ExceptionHandling::SjLj:
   case ExceptionHandling::DwarfCFI:
     DE = new DwarfCFIException(this);
-    return false;
+    break;
   case ExceptionHandling::ARM:
     DE = new ARMException(this);
-    return false;
+    break;
   case ExceptionHandling::Win64:
     DE = new Win64Exception(this);
-    return false;
+    break;
   }
-
-  llvm_unreachable("Unknown exception type.");
+  if (DE)
+    Handlers.push_back(HandlerInfo(DE, EHTimerName, DWARFGroupName));
+  return false;
 }
 
 void AsmPrinter::EmitLinkage(const GlobalValue *GV, MCSymbol *GVSym) const {
@@ -311,8 +315,11 @@ void AsmPrinter::EmitGlobalVariable(const GlobalVariable *GV) {
   // sections and expected to be contiguous (e.g. ObjC metadata).
   unsigned AlignLog = getGVAlignmentLog2(GV, *DL);
 
-  if (DD)
-    DD->setSymbolSize(GVSym, Size);
+  for (unsigned I = 0, E = Handlers.size(); I != E; ++I) {
+    const HandlerInfo &OI = Handlers[I];
+    NamedRegionTimer T(OI.TimerName, OI.TimerGroupName, TimePassesIsEnabled);
+    OI.Handler->setSymbolSize(GVSym, Size);
+  }
 
   // Handle common and BSS local symbols (.lcomm).
   if (GVKind.isCommon() || GVKind.isBSSLocal()) {
@@ -482,13 +489,10 @@ void AsmPrinter::EmitFunctionHeader() {
   }
 
   // Emit pre-function debug and/or EH information.
-  if (DE) {
-    NamedRegionTimer T(EHTimerName, DWARFGroupName, TimePassesIsEnabled);
-    DE->beginFunction(MF);
-  }
-  if (DD) {
-    NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled);
-    DD->beginFunction(MF);
+  for (unsigned I = 0, E = Handlers.size(); I != E; ++I) {
+    const HandlerInfo &OI = Handlers[I];
+    NamedRegionTimer T(OI.TimerName, OI.TimerGroupName, TimePassesIsEnabled);
+    OI.Handler->beginFunction(MF);
   }
 
   // Emit the prefix data.
@@ -693,7 +697,7 @@ void AsmPrinter::EmitFunctionBody() {
   // Emit target-specific gunk before the function body.
   EmitFunctionBodyStart();
 
-  bool ShouldPrintDebugScopes = DD && MMI->hasDebugInfo();
+  bool ShouldPrintDebugScopes = MMI->hasDebugInfo();
 
   // Print out code for the function.
   bool HasAnyRealCode = false;
@@ -714,8 +718,12 @@ void AsmPrinter::EmitFunctionBody() {
       }
 
       if (ShouldPrintDebugScopes) {
-        NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled);
-        DD->beginInstruction(II);
+        for (unsigned III = 0, EEE = Handlers.size(); III != EEE; ++III) {
+          const HandlerInfo &OI = Handlers[III];
+          NamedRegionTimer T(OI.TimerName, OI.TimerGroupName,
+                             TimePassesIsEnabled);
+          OI.Handler->beginInstruction(II);
+        }
       }
 
       if (isVerbose())
@@ -754,8 +762,12 @@ void AsmPrinter::EmitFunctionBody() {
       }
 
       if (ShouldPrintDebugScopes) {
-        NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled);
-        DD->endInstruction(II);
+        for (unsigned III = 0, EEE = Handlers.size(); III != EEE; ++III) {
+          const HandlerInfo &OI = Handlers[III];
+          NamedRegionTimer T(OI.TimerName, OI.TimerGroupName,
+                             TimePassesIsEnabled);
+          OI.Handler->endInstruction();
+        }
       }
     }
   }
@@ -811,14 +823,11 @@ void AsmPrinter::EmitFunctionBody() {
     OutStreamer.EmitELFSize(CurrentFnSym, SizeExp);
   }
 
-  // Emit post-function debug information.
-  if (DD) {
-    NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled);
-    DD->endFunction(MF);
-  }
-  if (DE) {
-    NamedRegionTimer T(EHTimerName, DWARFGroupName, TimePassesIsEnabled);
-    DE->endFunction();
+  // Emit post-function debug and/or EH information.
+  for (unsigned I = 0, E = Handlers.size(); I != E; ++I) {
+    const HandlerInfo &OI = Handlers[I];
+    NamedRegionTimer T(OI.TimerName, OI.TimerGroupName, TimePassesIsEnabled);
+    OI.Handler->endFunction(MF);
   }
   MMI->EndFunction();
 
@@ -907,20 +916,15 @@ bool AsmPrinter::doFinalization(Module &M) {
   OutStreamer.Flush();
 
   // Finalize debug and EH information.
-  if (DE) {
-    {
-      NamedRegionTimer T(EHTimerName, DWARFGroupName, TimePassesIsEnabled);
-      DE->endModule();
-    }
-    delete DE; DE = 0;
-  }
-  if (DD) {
-    {
-      NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled);
-      DD->endModule();
-    }
-    delete DD; DD = 0;
-  }
+  for (unsigned I = 0, E = Handlers.size(); I != E; ++I) {
+    const HandlerInfo &OI = Handlers[I];
+    NamedRegionTimer T(OI.TimerName, OI.TimerGroupName,
+                       TimePassesIsEnabled);
+    OI.Handler->endModule();
+    delete OI.Handler;
+  }
+  Handlers.clear();
+  DD = 0;
 
   // If the target wants to know about weak references, print them all.
   if (MAI->getWeakRefDirective()) {

llvm/lib/CodeGen/AsmPrinter/AsmPrinterHandler.h

@@ -0,0 +1,56 @@
+//===-- lib/CodeGen/AsmPrinter/AsmPrinterHandler.h -------------*- C++ -*--===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains a generic interface for AsmPrinter handlers,
+// like debug and EH info emitters.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef CODEGEN_ASMPRINTER_ASMPRINTERHANDLER_H__
+#define CODEGEN_ASMPRINTER_ASMPRINTERHANDLER_H__
+
+#include "llvm/Support/DataTypes.h"
+
+namespace llvm {
+
+class MachineFunction;
+class MachineInstr;
+class MCSymbol;
+
+/// \brief Collects and handles AsmPrinter objects required to build debug
+/// or EH information.
+class AsmPrinterHandler {
+public:
+  virtual ~AsmPrinterHandler() {}
+
+  /// \brief For symbols that have a size designated (e.g. common symbols),
+  /// this tracks that size.
+  virtual void setSymbolSize(const MCSymbol *Sym, uint64_t Size) = 0;
+
+  /// \brief Emit all sections that should come after the content.
+  virtual void endModule() = 0;
+
+  /// \brief Gather pre-function debug information.
+  /// Every beginFunction(MF) call should be followed by an endFunction(MF) call.
+  virtual void beginFunction(const MachineFunction *MF) = 0;
+
+  /// \brief Gather post-function debug information.
+  /// Please note that some AsmPrinter implementationss may not call
+  /// beginFunction at all.
+  virtual void endFunction(const MachineFunction *MF) = 0;
+
+  /// \brief Process beginning of an instruction.
+  virtual void beginInstruction(const MachineInstr *MI) = 0;
+
+  /// \brief Process end of an instruction.
+  virtual void endInstruction() = 0;
+};
+} // End of namespace llvm
+
+#endif

llvm/lib/CodeGen/AsmPrinter/DIE.cpp

@@ -390,7 +390,9 @@ unsigned DIEEntry::getRefAddrSize(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.
-  if (AP->getDwarfDebug()->getDwarfVersion() == 2)
+  const DwarfDebug *DD = AP->getDwarfDebug();
+  assert(DD && "Expected Dwarf Debug info to be available");
+  if (DD->getDwarfVersion() == 2)
     return AP->getDataLayout().getPointerSize();
   return sizeof(int32_t);
 }

llvm/lib/CodeGen/AsmPrinter/DwarfCFIException.cpp

@@ -137,7 +137,7 @@ void DwarfCFIException::beginFunction(const MachineFunction *MF) {
 
 /// endFunction - Gather and emit post-function exception information.
 ///
-void DwarfCFIException::endFunction() {
+void DwarfCFIException::endFunction(const MachineFunction *) {
   if (!shouldEmitPersonality && !shouldEmitMoves)
     return;