This reverts commit r200064 and r200051.

r200064 depends on r200051.

r200051 is broken: I tries to replace .mips_hack_elf_flags, which is a good
thing, but what it replaces it with is even worse.

The new emitMipsELFFlags it adds corresponds to no assembly directive, is not
marked as a hack and is not even printed to the .s file.

The patch also introduces more uses of hasRawTextSupport.

The correct way to remove .mips_hack_elf_flags is to have the mips target
streamer handle the default flags (and command line options). That way the
same code path is used for asm and obj. The streamer interface should *really*
correspond to what is printed in the .s file.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200078 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Target/Mips/AsmParser/MipsAsmParser.cpp

@@ -21,9 +21,6 @@
 #include "llvm/MC/MCSubtargetInfo.h"
 #include "llvm/MC/MCSymbol.h"
 #include "llvm/MC/MCTargetAsmParser.h"
-#include "llvm/Support/ELF.h"
-#include "llvm/Support/TargetRegistry.h"
-#include "llvm/ADT/APInt.h"
 #include "llvm/Support/MathExtras.h"
 #include "llvm/Support/TargetRegistry.h"
 
@@ -197,6 +194,7 @@ class MipsAsmParser : public MCTargetAsmParser {
 
   bool isEvaluated(const MCExpr *Expr);
   bool parseDirectiveSet();
+  bool parseDirectiveMipsHackELFFlags();
   bool parseDirectiveOption();
 
   bool parseSetAtDirective();
@@ -259,17 +257,13 @@ class MipsAsmParser : public MCTargetAsmParser {
   // Example: INSERT.B $w0[n], $1 => 16 > n >= 0
   bool validateMSAIndex(int Val, int RegKind);
 
-  // Set ELF flags based on defaults and commandline arguments.
-  void processInitialEFlags();
-
 public:
   MipsAsmParser(MCSubtargetInfo &sti, MCAsmParser &parser,
                 const MCInstrInfo &MII)
       : MCTargetAsmParser(), STI(sti), Parser(parser),
         hasConsumedDollar(false) {
     // Initialize the set of available features.
     setAvailableFeatures(ComputeAvailableFeatures(STI.getFeatureBits()));
-    processInitialEFlags();
   }
 
   MCAsmParser &getParser() const { return Parser; }
@@ -2435,6 +2429,17 @@ bool MipsAsmParser::parseDirectiveSet() {
   return true;
 }
 
+bool MipsAsmParser::parseDirectiveMipsHackELFFlags() {
+  int64_t Flags = 0;
+  if (Parser.parseAbsoluteExpression(Flags)) {
+    TokError("unexpected token");
+    return false;
+  }
+
+  getTargetStreamer().emitMipsHackELFFlags(Flags);
+  return false;
+}
+
 /// parseDirectiveWord
 ///  ::= .word [ expression (, expression)* ]
 bool MipsAsmParser::parseDirectiveWord(unsigned Size, SMLoc L) {
@@ -2553,6 +2558,9 @@ bool MipsAsmParser::ParseDirective(AsmToken DirectiveID) {
     return false;
   }
 
+  if (IDVal == ".mips_hack_elf_flags")
+    return parseDirectiveMipsHackELFFlags();
+
   if (IDVal == ".option")
     return parseDirectiveOption();
 
@@ -2569,43 +2577,6 @@ bool MipsAsmParser::ParseDirective(AsmToken DirectiveID) {
   return true;
 }
 
-void MipsAsmParser::processInitialEFlags() {
-  // Start will a clean slate.
-  unsigned EFlags = 0;
-  unsigned FeatureBits = STI.getFeatureBits();
-
-  // Default settings
-  EFlags |= ELF::EF_MIPS_NOREORDER | ELF::EF_MIPS_PIC | ELF::EF_MIPS_ABI_O32;
-
-  // ISA
-  if (FeatureBits & Mips::FeatureMips64r2) {
-    EFlags |= ELF::EF_MIPS_ARCH_64R2;
-    EFlags &= ~ELF::EF_MIPS_ABI_O32;
-  } else if (FeatureBits & Mips::FeatureMips64) {
-    EFlags |= ELF::EF_MIPS_ARCH_64;
-    EFlags &= ~ELF::EF_MIPS_ABI_O32;
-  } else if (FeatureBits & Mips::FeatureMips32r2)
-    EFlags |= ELF::EF_MIPS_ARCH_32R2;
-  else if (FeatureBits & Mips::FeatureMips32)
-    EFlags |= ELF::EF_MIPS_ARCH_32;
-  else if (FeatureBits & Mips::FeatureO32)
-    EFlags |= ELF::EF_MIPS_ABI_O32; // This is really a zero
-
-  // ASE
-  if (FeatureBits & Mips::FeatureMicroMips)
-    EFlags |= ELF::EF_MIPS_MICROMIPS;
-  else if (FeatureBits & Mips::FeatureMips16)
-    EFlags |= ELF::EF_MIPS_ARCH_ASE_M16;
-
-  // ABI
-  // TODO: n32/eabi
-
-  // Linkage model
-  // TODO: pic/cpic/static
-
-  getTargetStreamer().emitMipsELFFlags(EFlags);
-}
-
 extern "C" void LLVMInitializeMipsAsmParser() {
   RegisterMCAsmParser<MipsAsmParser> X(TheMipsTarget);
   RegisterMCAsmParser<MipsAsmParser> Y(TheMipselTarget);

lib/Target/Mips/MCTargetDesc/MipsTargetStreamer.cpp

@@ -21,13 +21,23 @@
 
 using namespace llvm;
 
+static cl::opt<bool> PrintHackDirectives("print-hack-directives",
+                                         cl::init(false), cl::Hidden);
+
 // Pin vtable to this file.
 void MipsTargetStreamer::anchor() {}
 
 MipsTargetAsmStreamer::MipsTargetAsmStreamer(formatted_raw_ostream &OS)
     : OS(OS) {}
 
-void MipsTargetAsmStreamer::emitMipsELFFlags(unsigned Flags) { return; }
+void MipsTargetAsmStreamer::emitMipsHackELFFlags(unsigned Flags) {
+  if (!PrintHackDirectives)
+    return;
+
+  OS << "\t.mips_hack_elf_flags 0x";
+  OS.write_hex(Flags);
+  OS << '\n';
+}
 
 void MipsTargetAsmStreamer::emitDirectiveSetMicroMips() {
   OS << "\t.set\tmicromips\n";
@@ -75,7 +85,7 @@ MCELFStreamer &MipsTargetELFStreamer::getStreamer() {
   return static_cast<MCELFStreamer &>(*Streamer);
 }
 
-void MipsTargetELFStreamer::emitMipsELFFlags(unsigned Flags) {
+void MipsTargetELFStreamer::emitMipsHackELFFlags(unsigned Flags) {
   MCAssembler &MCA = getStreamer().getAssembler();
   MCA.setELFHeaderEFlags(Flags);
 }

lib/Target/Mips/MipsAsmPrinter.cpp

@@ -108,6 +108,7 @@ void MipsAsmPrinter::EmitInstruction(const MachineInstr *MI) {
     return;
   }
 
+
   MachineBasicBlock::const_instr_iterator I = MI;
   MachineBasicBlock::const_instr_iterator E = MI->getParent()->instr_end();
 
@@ -633,57 +634,54 @@ void MipsAsmPrinter::EmitStartOfAsmFile(Module &M) {
 
 }
 
-void MipsAsmPrinter::processInitialEFlags() {
-  // Not having this check would work too, but would have us chew through
-  // code that it doesn't use for RawText.
-  if (OutStreamer.hasRawTextSupport())
-    return;
-
+static void emitELFHeaderFlagsCG(MipsTargetStreamer &TargetStreamer,
+                                 const MipsSubtarget &Subtarget) {
   // Update e_header flags
   unsigned EFlags = 0;
 
   // TODO: Need to add -mabicalls and -mno-abicalls flags.
   // Currently we assume that -mabicalls is the default.
   EFlags |= ELF::EF_MIPS_CPIC;
 
-  if (Subtarget->inMips16Mode())
+  if (Subtarget.inMips16Mode())
     EFlags |= ELF::EF_MIPS_ARCH_ASE_M16;
   else
     EFlags |= ELF::EF_MIPS_NOREORDER;
 
   // Architecture
-  if (Subtarget->hasMips64r2())
+  if (Subtarget.hasMips64r2())
     EFlags |= ELF::EF_MIPS_ARCH_64R2;
-  else if (Subtarget->hasMips64())
+  else if (Subtarget.hasMips64())
     EFlags |= ELF::EF_MIPS_ARCH_64;
-  else if (Subtarget->hasMips32r2())
+  else if (Subtarget.hasMips32r2())
     EFlags |= ELF::EF_MIPS_ARCH_32R2;
   else
     EFlags |= ELF::EF_MIPS_ARCH_32;
 
-  if (Subtarget->inMicroMipsMode())
+  if (Subtarget.inMicroMipsMode())
     EFlags |= ELF::EF_MIPS_MICROMIPS;
 
   // ABI
-  if (Subtarget->isABI_O32())
+  if (Subtarget.isABI_O32())
     EFlags |= ELF::EF_MIPS_ABI_O32;
 
   // Relocation Model
-  Reloc::Model RM = Subtarget->getRelocationModel();
+  Reloc::Model RM = Subtarget.getRelocationModel();
   if (RM == Reloc::PIC_ || RM == Reloc::Default)
     EFlags |= ELF::EF_MIPS_PIC;
   else if (RM == Reloc::Static)
     ; // Do nothing for Reloc::Static
   else
     llvm_unreachable("Unsupported relocation model for e_flags");
 
-  getTargetStreamer().emitMipsELFFlags(EFlags);
+  TargetStreamer.emitMipsHackELFFlags(EFlags);
 }
 
 void MipsAsmPrinter::EmitEndOfAsmFile(Module &M) {
   // Emit Mips ELF register info
   Subtarget->getMReginfo().emitMipsReginfoSectionCG(
              OutStreamer, getObjFileLowering(), *Subtarget);
+  emitELFHeaderFlagsCG(getTargetStreamer(), *Subtarget);
 }
 
 void MipsAsmPrinter::PrintDebugValueComment(const MachineInstr *MI,

lib/Target/Mips/MipsAsmPrinter.h

@@ -50,10 +50,6 @@ class LLVM_LIBRARY_VISIBILITY MipsAsmPrinter : public AsmPrinter {
   /// pool entries so we can properly mark them as data regions.
   bool InConstantPool;
 
-  // If object output, set initial eflags.
-  // This includes both default and commandline flags that affect the output
-  // ELF header flags.
-  void processInitialEFlags();
 
 public:
 
@@ -65,7 +61,6 @@ class LLVM_LIBRARY_VISIBILITY MipsAsmPrinter : public AsmPrinter {
     : AsmPrinter(TM, Streamer), MCP(0), InConstantPool(false),
       MCInstLowering(*this) {
     Subtarget = &TM.getSubtarget<MipsSubtarget>();
-    processInitialEFlags();
   }
 
   virtual const char *getPassName() const {
@@ -108,7 +103,6 @@ class LLVM_LIBRARY_VISIBILITY MipsAsmPrinter : public AsmPrinter {
   void EmitStartOfAsmFile(Module &M);
   void EmitEndOfAsmFile(Module &M);
   void PrintDebugValueComment(const MachineInstr *MI, raw_ostream &OS);
-
 };
 }
 

lib/Target/Mips/MipsTargetStreamer.h

@@ -18,7 +18,7 @@ class MipsTargetStreamer : public MCTargetStreamer {
   virtual void anchor();
 
 public:
-  virtual void emitMipsELFFlags(unsigned Flags) = 0;
+  virtual void emitMipsHackELFFlags(unsigned Flags) = 0;
   virtual void emitDirectiveSetMicroMips() = 0;
   virtual void emitDirectiveSetNoMicroMips() = 0;
   virtual void emitDirectiveSetMips16() = 0;
@@ -34,7 +34,7 @@ class MipsTargetAsmStreamer : public MipsTargetStreamer {
 
 public:
   MipsTargetAsmStreamer(formatted_raw_ostream &OS);
-  virtual void emitMipsELFFlags(unsigned Flags);
+  virtual void emitMipsHackELFFlags(unsigned Flags);
   virtual void emitDirectiveSetMicroMips();
   virtual void emitDirectiveSetNoMicroMips();
   virtual void emitDirectiveSetMips16();
@@ -56,7 +56,7 @@ class MipsTargetELFStreamer : public MipsTargetStreamer {
   virtual void emitLabel(MCSymbol *Symbol) LLVM_OVERRIDE;
 
   // FIXME: emitMipsHackELFFlags() will be removed from this class.
-  virtual void emitMipsELFFlags(unsigned Flags);
+  virtual void emitMipsHackELFFlags(unsigned Flags);
   virtual void emitDirectiveSetMicroMips();
   virtual void emitDirectiveSetNoMicroMips();
   virtual void emitDirectiveSetMips16();