Revert r129518, "Change ELF systems to use CFI for producing the EH tables. This reduces the"

It broke several builds.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@129557 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/CodeGen/AsmPrinter.h

@@ -183,8 +183,6 @@ namespace llvm {
     /// function.
     void EmitFunctionBody();
 
-    void emitPrologLabel(const MachineInstr &MI);
-
     /// EmitConstantPool - Print to the current output stream assembly
     /// representations of the constants in the constant pool MCP. This is
     /// used to print out constants which have been "spilled to memory" by

lib/CodeGen/AsmPrinter/AsmPrinter.cpp

@@ -33,7 +33,6 @@
 #include "llvm/MC/MCStreamer.h"
 #include "llvm/MC/MCSymbol.h"
 #include "llvm/Target/Mangler.h"
-#include "llvm/Target/TargetAsmInfo.h"
 #include "llvm/Target/TargetData.h"
 #include "llvm/Target/TargetInstrInfo.h"
 #include "llvm/Target/TargetLowering.h"
@@ -625,45 +624,6 @@ static bool EmitDebugValueComment(const MachineInstr *MI, AsmPrinter &AP) {
   return true;
 }
 
-void AsmPrinter::emitPrologLabel(const MachineInstr &MI) {
-  MCSymbol *Label = MI.getOperand(0).getMCSymbol();
-  if (MAI->getExceptionHandlingType() != ExceptionHandling::DwarfCFI) {
-    OutStreamer.EmitLabel(Label);
-    return;
-  }
-
-  const MachineFunction &MF = *MI.getParent()->getParent();
-  MachineModuleInfo &MMI = MF.getMMI();
-  std::vector<MachineMove> &Moves = MMI.getFrameMoves();
-  const MachineMove *Move = NULL;
-  for (std::vector<MachineMove>::iterator I = Moves.begin(),
-         E = Moves.end(); I != E; ++I) {
-    if (I->getLabel() == Label) {
-      Move = &*I;
-      break;
-    }
-  }
-  assert(Move);
-
-  const MachineLocation &Dst = Move->getDestination();
-  const MachineLocation &Src = Move->getSource();
-  const TargetAsmInfo &AsmInfo = OutContext.getTargetAsmInfo();
-  if (Dst.isReg() && Dst.getReg() == MachineLocation::VirtualFP) {
-    if (Src.getReg() == MachineLocation::VirtualFP)
-      OutStreamer.EmitCFIDefCfaOffset(-Src.getOffset());
-    else {
-      unsigned Reg = AsmInfo.getDwarfRegNum(Src.getReg(), true);
-      OutStreamer.EmitCFIDefCfa(Reg, -Src.getOffset());
-    }
-  } else if (Src.isReg() && Src.getReg() == MachineLocation::VirtualFP) {
-    unsigned Reg = AsmInfo.getDwarfRegNum(Dst.getReg(), true);
-    OutStreamer.EmitCFIDefCfaRegister(Reg);
-  } else {
-    unsigned Reg = AsmInfo.getDwarfRegNum(Src.getReg(), true);
-    OutStreamer.EmitCFIOffset(Reg, -Dst.getOffset());
-  }
-}
-
 /// EmitFunctionBody - This method emits the body and trailer for a
 /// function.
 void AsmPrinter::EmitFunctionBody() {
@@ -700,9 +660,6 @@ void AsmPrinter::EmitFunctionBody() {
 
       switch (II->getOpcode()) {
       case TargetOpcode::PROLOG_LABEL:
-        emitPrologLabel(*II);
-        break;
-
       case TargetOpcode::EH_LABEL:
       case TargetOpcode::GC_LABEL:
         OutStreamer.EmitLabel(II->getOperand(0).getMCSymbol());

lib/CodeGen/AsmPrinter/DwarfCFIException.cpp

@@ -32,7 +32,6 @@
 #include "llvm/Target/TargetOptions.h"
 #include "llvm/Target/TargetRegisterInfo.h"
 #include "llvm/Support/Dwarf.h"
-#include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/FormattedStream.h"
 #include "llvm/ADT/SmallString.h"
 #include "llvm/ADT/StringExtras.h"
@@ -61,16 +60,11 @@ void DwarfCFIException::EndModule() {
   // Begin eh frame section.
   Asm->OutStreamer.SwitchSection(TLOF.getEHFrameSection());
 
-  if ((PerEncoding & 0x70) != dwarf::DW_EH_PE_pcrel)
-    return;
-
   // Emit references to all used personality functions
   const std::vector<const Function*> &Personalities = MMI->getPersonalities();
   for (size_t i = 0, e = Personalities.size(); i != e; ++i) {
     Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("personality", i));
-    const MCSymbol *Sym = Asm->Mang->getSymbol(Personalities[i]);
-    unsigned Size = Asm->TM.getTargetData()->getPointerSize();
-    Asm->OutStreamer.EmitSymbolValue(Sym, Size);
+    Asm->EmitReference(Personalities[i], PerEncoding);
   }
 }
 
@@ -93,9 +87,17 @@ void DwarfCFIException::BeginFunction(const MachineFunction *MF) {
 
   shouldEmitTableModule |= shouldEmitTable;
 
-  if (shouldEmitMoves || shouldEmitTable)
+  if (shouldEmitMoves) {
+    const TargetFrameLowering *TFL = Asm->TM.getFrameLowering();
     Asm->OutStreamer.EmitCFIStartProc();
 
+    // Indicate locations of general callee saved registers in frame.
+    std::vector<MachineMove> Moves;
+    TFL->getInitialFrameState(Moves);
+    Asm->EmitCFIFrameMoves(Moves);
+    Asm->EmitCFIFrameMoves(MMI->getFrameMoves());
+  }
+
   if (!shouldEmitTable)
     return;
 
@@ -110,25 +112,11 @@ void DwarfCFIException::BeginFunction(const MachineFunction *MF) {
 
   // Indicate personality routine, if any.
   unsigned PerEncoding = TLOF.getPersonalityEncoding();
-  const Function *Per = MMI->getPersonalities()[MMI->getPersonalityIndex()];
-  if (PerEncoding == dwarf::DW_EH_PE_omit || !Per)
-    return;
-
-  const MCSymbol *Sym;
-  switch (PerEncoding & 0x70) {
-  default:
-    report_fatal_error("We do not support this DWARF encoding yet!");
-  case dwarf::DW_EH_PE_absptr: {
-    Sym = Asm->Mang->getSymbol(Per);
-    break;
-  }
-  case dwarf::DW_EH_PE_pcrel: {
-    Sym = Asm->GetTempSymbol("personality",
-                             MMI->getPersonalityIndex());
-    break;
-  }
-  }
-  Asm->OutStreamer.EmitCFIPersonality(Sym, PerEncoding);
+  if (PerEncoding != dwarf::DW_EH_PE_omit &&
+      MMI->getPersonalities()[MMI->getPersonalityIndex()])
+    Asm->OutStreamer.EmitCFIPersonality(Asm->GetTempSymbol("personality",
+                                                    MMI->getPersonalityIndex()),
+                                        PerEncoding);
 }
 
 /// EndFunction - Gather and emit post-function exception information.

lib/Target/TargetLoweringObjectFile.cpp

@@ -314,7 +314,7 @@ getExprForDwarfReference(const MCSymbol *Sym, Mangler *Mang,
                          MCStreamer &Streamer) const {
   const MCExpr *Res = MCSymbolRefExpr::Create(Sym, getContext());
 
-  switch (Encoding & 0x70) {
+  switch (Encoding & 0xF0) {
   default:
     report_fatal_error("We do not support this DWARF encoding yet!");
   case dwarf::DW_EH_PE_absptr:

lib/Target/X86/X86FrameLowering.cpp

@@ -22,7 +22,6 @@
 #include "llvm/CodeGen/MachineInstrBuilder.h"
 #include "llvm/CodeGen/MachineModuleInfo.h"
 #include "llvm/CodeGen/MachineRegisterInfo.h"
-#include "llvm/MC/MCAsmInfo.h"
 #include "llvm/Target/TargetData.h"
 #include "llvm/Target/TargetOptions.h"
 #include "llvm/Support/CommandLine.h"
@@ -477,15 +476,6 @@ void X86FrameLowering::emitPrologue(MachineFunction &MF) const {
         .addReg(StackPtr);
 
     if (needsFrameMoves) {
-      const MCAsmInfo &MAI = MMI.getContext().getAsmInfo();
-      if (MAI.getExceptionHandlingType() == ExceptionHandling::DwarfCFI) {
-        MCSymbol *FrameLabel0 = MMI.getContext().CreateTempSymbol();
-        BuildMI(MBB, MBBI, DL, TII.get(X86::PROLOG_LABEL)).addSym(FrameLabel0);
-        MachineLocation FPSrc0(FramePtr);
-        MachineLocation FPDst0(FramePtr, -2 * stackGrowth);
-        Moves.push_back(MachineMove(FrameLabel0, FPDst0, FPSrc0));
-      }
-
       // Mark effective beginning of when frame pointer becomes valid.
       MCSymbol *FrameLabel = MMI.getContext().CreateTempSymbol();
       BuildMI(MBB, MBBI, DL, TII.get(X86::PROLOG_LABEL)).addSym(FrameLabel);
@@ -625,7 +615,7 @@ void X86FrameLowering::emitPrologue(MachineFunction &MF) const {
     emitSPUpdate(MBB, MBBI, StackPtr, -(int64_t)NumBytes, Is64Bit,
                  TII, *RegInfo);
 
-  if (( (!HasFP && NumBytes) || PushedRegs) && needsFrameMoves) {
+  if ((NumBytes || PushedRegs) && needsFrameMoves) {
     // Mark end of stack pointer adjustment.
     MCSymbol *Label = MMI.getContext().CreateTempSymbol();
     BuildMI(MBB, MBBI, DL, TII.get(X86::PROLOG_LABEL)).addSym(Label);

lib/Target/X86/X86MCAsmInfo.cpp

@@ -89,9 +89,7 @@ X86ELFMCAsmInfo::X86ELFMCAsmInfo(const Triple &T) {
   SupportsDebugInformation = true;
 
   // Exceptions handling
-  ExceptionsType = ExceptionHandling::DwarfCFI;
-
-  DwarfRequiresFrameSection = false;
+  ExceptionsType = ExceptionHandling::DwarfTable;
 
   // OpenBSD has buggy support for .quad in 32-bit mode, just split into two
   // .words.

test/CodeGen/X86/2007-05-05-Personality.ll

@@ -1,7 +1,4 @@
-; RUN: llc < %s -mtriple=i686-pc-linux-gnu -o - | FileCheck %s
-
-; CHECK: .cfi_lsda 0, .Lexception0
-; CHECK: .cfi_personality 0, __gnat_eh_personality
+; RUN: llc < %s -mtriple=i686-pc-linux-gnu -o - | grep zPL
 
 @error = external global i8		; <i8*> [#uses=2]
 

test/CodeGen/X86/2008-12-12-PrivateEHSymbol.ll

@@ -0,0 +1,12 @@
+; RUN: llc < %s -march=x86-64 -mtriple=x86_64-unknown-linux-gnu | grep ^.L_Z1fv.eh
+; RUN: llc < %s -march=x86    -mtriple=i686-unknown-linux-gnu | grep ^.L_Z1fv.eh
+; RUN: llc < %s -march=x86-64 -mtriple=x86_64-apple-darwin9 | grep ^__Z1fv.eh
+; RUN: llc < %s -march=x86    -mtriple=i386-apple-darwin9 | grep ^__Z1fv.eh
+
+define void @_Z1fv() {
+entry:
+	br label %return
+
+return:
+	ret void
+}

test/CodeGen/X86/aliases.ll

@@ -1,4 +1,6 @@
 ; RUN: llc < %s -mtriple=i686-pc-linux-gnu -asm-verbose=false -o %t
+; RUN: grep { = } %t   | count 16
+; RUN: grep set %t   | count 18
 ; RUN: grep globl %t | count 6
 ; RUN: grep weak %t  | count 1
 ; RUN: grep hidden %t | count 1