Implement the missing bits corresponding to .mips_hack_elf_flags.

These were:
* noreorder handling on the target object streamer and asm parser.
* setting the initial flag bits based on the enabled features.
* setting the elf header flag for micromips

It is *really* depressing I am the one doing this instead of someone at
mips actually taking the time to understand the infrastructure.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200138 91177308-0d34-0410-b5e6-96231b3b80d8

5 files changed, 47 insertions, 86 deletions

diff --git a/lib/Target/Mips/AsmParser/MipsAsmParser.cpp b/lib/Target/Mips/AsmParser/MipsAsmParser.cpp
index aae2dcd16e..74e4fffcee 100644
--- a/lib/Target/Mips/AsmParser/MipsAsmParser.cpp
+++ b/lib/Target/Mips/AsmParser/MipsAsmParser.cpp
@@ -194,7 +194,6 @@ class MipsAsmParser : public MCTargetAsmParser {
 
   bool isEvaluated(const MCExpr *Expr);
   bool parseDirectiveSet();
-  bool parseDirectiveMipsHackELFFlags();
   bool parseDirectiveOption();
 
   bool parseSetAtDirective();
@@ -2311,6 +2310,7 @@ bool MipsAsmParser::parseSetNoReorderDirective() {
     return false;
   }
   Options.setNoreorder();
+  getTargetStreamer().emitDirectiveSetNoReorder();
   Parser.Lex(); // Consume the EndOfStatement.
   return false;
 }
@@ -2429,17 +2429,6 @@ 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) {
@@ -2558,9 +2547,6 @@ bool MipsAsmParser::ParseDirective(AsmToken DirectiveID) {
     return false;
   }
 
-  if (IDVal == ".mips_hack_elf_flags")
-    return parseDirectiveMipsHackELFFlags();
-
   if (IDVal == ".option")
     return parseDirectiveOption();
 
diff --git a/lib/Target/Mips/MCTargetDesc/MipsMCTargetDesc.cpp b/lib/Target/Mips/MCTargetDesc/MipsMCTargetDesc.cpp
index 6d3662cb80..f7cf1c1e00 100644
--- a/lib/Target/Mips/MCTargetDesc/MipsMCTargetDesc.cpp
+++ b/lib/Target/Mips/MCTargetDesc/MipsMCTargetDesc.cpp
@@ -134,7 +134,7 @@ static MCStreamer *createMCStreamer(const Target &T, StringRef TT,
                                     bool RelaxAll, bool NoExecStack) {
   MCStreamer *S =
       createELFStreamer(Context, MAB, OS, Emitter, RelaxAll, NoExecStack);
-  new MipsTargetELFStreamer(*S);
+  new MipsTargetELFStreamer(*S, STI);
   return S;
 }
 
diff --git a/lib/Target/Mips/MCTargetDesc/MipsTargetStreamer.cpp b/lib/Target/Mips/MCTargetDesc/MipsTargetStreamer.cpp
index d635bbf80f..82e8a96879 100644
--- a/lib/Target/Mips/MCTargetDesc/MipsTargetStreamer.cpp
+++ b/lib/Target/Mips/MCTargetDesc/MipsTargetStreamer.cpp
@@ -12,8 +12,10 @@
 //===----------------------------------------------------------------------===//
 
 #include "MipsTargetStreamer.h"
+#include "MipsMCTargetDesc.h"
 #include "llvm/MC/MCELF.h"
 #include "llvm/MC/MCSymbol.h"
+#include "llvm/MC/MCSubtargetInfo.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/ELF.h"
 #include "llvm/Support/ErrorHandling.h"
@@ -21,9 +23,6 @@
 
 using namespace llvm;
 
-static cl::opt<bool> PrintHackDirectives("print-hack-directives",
-                                         cl::init(false), cl::Hidden);
-
 // Pin vtable to this file.
 void MipsTargetStreamer::anchor() {}
 
@@ -33,15 +32,6 @@ MipsTargetAsmStreamer::MipsTargetAsmStreamer(MCStreamer &S,
                                              formatted_raw_ostream &OS)
     : MipsTargetStreamer(S), OS(OS) {}
 
-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";
 }
@@ -96,8 +86,38 @@ void MipsTargetAsmStreamer::emitDirectiveOptionPic0() {
 }
 
 // This part is for ELF object output.
-MipsTargetELFStreamer::MipsTargetELFStreamer(MCStreamer &S)
-    : MipsTargetStreamer(S), MicroMipsEnabled(false) {}
+MipsTargetELFStreamer::MipsTargetELFStreamer(MCStreamer &S,
+                                             const MCSubtargetInfo &STI)
+    : MipsTargetStreamer(S), MicroMipsEnabled(false) {
+  MCAssembler &MCA = getStreamer().getAssembler();
+  uint64_t Features = STI.getFeatureBits();
+  Triple T(STI.getTargetTriple());
+
+  // Update e_header flags
+  unsigned EFlags = 0;
+
+  // Architecture
+  if (Features & Mips::FeatureMips64r2)
+    EFlags |= ELF::EF_MIPS_ARCH_64R2;
+  else if (Features & Mips::FeatureMips64)
+    EFlags |= ELF::EF_MIPS_ARCH_64;
+  else if (Features & Mips::FeatureMips32r2)
+    EFlags |= ELF::EF_MIPS_ARCH_32R2;
+  else if (Features & Mips::FeatureMips32)
+    EFlags |= ELF::EF_MIPS_ARCH_32;
+
+  if (T.isArch64Bit()) {
+    EFlags |= ELF::EF_MIPS_ABI2;
+  } else {
+    if (Features & Mips::FeatureMips64r2 || Features & Mips::FeatureMips64)
+      EFlags |= ELF::EF_MIPS_32BITMODE;
+
+    // ABI
+    EFlags |= ELF::EF_MIPS_ABI_O32;
+  }
+
+  MCA.setELFHeaderEFlags(EFlags);
+}
 
 void MipsTargetELFStreamer::emitLabel(MCSymbol *Symbol) {
   if (!isMicroMipsEnabled())
@@ -117,13 +137,13 @@ MCELFStreamer &MipsTargetELFStreamer::getStreamer() {
   return static_cast<MCELFStreamer &>(Streamer);
 }
 
-void MipsTargetELFStreamer::emitMipsHackELFFlags(unsigned Flags) {
-  MCAssembler &MCA = getStreamer().getAssembler();
-  MCA.setELFHeaderEFlags(Flags);
-}
-
 void MipsTargetELFStreamer::emitDirectiveSetMicroMips() {
   MicroMipsEnabled = true;
+
+  MCAssembler &MCA = getStreamer().getAssembler();
+  unsigned Flags = MCA.getELFHeaderEFlags();
+  Flags |= ELF::EF_MIPS_MICROMIPS;
+  MCA.setELFHeaderEFlags(Flags);
 }
 
 void MipsTargetELFStreamer::emitDirectiveSetNoMicroMips() {
@@ -146,7 +166,10 @@ void MipsTargetELFStreamer::emitDirectiveSetReorder() {
 }
 
 void MipsTargetELFStreamer::emitDirectiveSetNoReorder() {
-  // FIXME: implement.
+  MCAssembler &MCA = getStreamer().getAssembler();
+  unsigned Flags = MCA.getELFHeaderEFlags();
+  Flags |= ELF::EF_MIPS_NOREORDER;
+  MCA.setELFHeaderEFlags(Flags);
 }
 
 void MipsTargetELFStreamer::emitDirectiveSetMacro() {
@@ -176,7 +199,7 @@ void MipsTargetELFStreamer::emitDirectiveEnt(const MCSymbol &Symbol) {
 void MipsTargetELFStreamer::emitDirectiveAbiCalls() {
   MCAssembler &MCA = getStreamer().getAssembler();
   unsigned Flags = MCA.getELFHeaderEFlags();
-  Flags |= ELF::EF_MIPS_CPIC;
+  Flags |= ELF::EF_MIPS_CPIC | ELF::EF_MIPS_PIC;
   MCA.setELFHeaderEFlags(Flags);
 }
 void MipsTargetELFStreamer::emitDirectiveOptionPic0() {
diff --git a/lib/Target/Mips/MipsAsmPrinter.cpp b/lib/Target/Mips/MipsAsmPrinter.cpp
index 048e0cacfb..8ce37b9161 100644
--- a/lib/Target/Mips/MipsAsmPrinter.cpp
+++ b/lib/Target/Mips/MipsAsmPrinter.cpp
@@ -636,54 +636,10 @@ void MipsAsmPrinter::EmitStartOfAsmFile(Module &M) {
 
 }
 
-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())
-    EFlags |= ELF::EF_MIPS_ARCH_ASE_M16;
-  else
-    EFlags |= ELF::EF_MIPS_NOREORDER;
-
-  // Architecture
-  if (Subtarget.hasMips64r2())
-    EFlags |= ELF::EF_MIPS_ARCH_64R2;
-  else if (Subtarget.hasMips64())
-    EFlags |= ELF::EF_MIPS_ARCH_64;
-  else if (Subtarget.hasMips32r2())
-    EFlags |= ELF::EF_MIPS_ARCH_32R2;
-  else
-    EFlags |= ELF::EF_MIPS_ARCH_32;
-
-  if (Subtarget.inMicroMipsMode())
-    EFlags |= ELF::EF_MIPS_MICROMIPS;
-
-  // ABI
-  if (Subtarget.isABI_O32())
-    EFlags |= ELF::EF_MIPS_ABI_O32;
-
-  // Relocation Model
-  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");
-
-  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,
diff --git a/lib/Target/Mips/MipsTargetStreamer.h b/lib/Target/Mips/MipsTargetStreamer.h
index b9272dc285..a8a846023d 100644
--- a/lib/Target/Mips/MipsTargetStreamer.h
+++ b/lib/Target/Mips/MipsTargetStreamer.h
@@ -19,7 +19,6 @@ class MipsTargetStreamer : public MCTargetStreamer {
 
 public:
   MipsTargetStreamer(MCStreamer &S);
-  virtual void emitMipsHackELFFlags(unsigned Flags) = 0;
   virtual void emitDirectiveSetMicroMips() = 0;
   virtual void emitDirectiveSetNoMicroMips() = 0;
   virtual void emitDirectiveSetMips16() = 0;
@@ -44,7 +43,6 @@ class MipsTargetAsmStreamer : public MipsTargetStreamer {
 
 public:
   MipsTargetAsmStreamer(MCStreamer &S, formatted_raw_ostream &OS);
-  virtual void emitMipsHackELFFlags(unsigned Flags);
   virtual void emitDirectiveSetMicroMips();
   virtual void emitDirectiveSetNoMicroMips();
   virtual void emitDirectiveSetMips16();
@@ -70,12 +68,10 @@ class MipsTargetELFStreamer : public MipsTargetStreamer {
 public:
   bool isMicroMipsEnabled() const { return MicroMipsEnabled; }
   MCELFStreamer &getStreamer();
-  MipsTargetELFStreamer(MCStreamer &S);
+  MipsTargetELFStreamer(MCStreamer &S, const MCSubtargetInfo &STI);
 
   virtual void emitLabel(MCSymbol *Symbol) LLVM_OVERRIDE;
 
-  // FIXME: emitMipsHackELFFlags() will be removed from this class.
-  virtual void emitMipsHackELFFlags(unsigned Flags);
   virtual void emitDirectiveSetMicroMips();
   virtual void emitDirectiveSetNoMicroMips();
   virtual void emitDirectiveSetMips16();