Add isOSNaCl, and add Asm subclasses for NaCl

Removes some of the FIXME cruft that suggest we should use subclassing.

BUG=

Review URL: https://codereview.chromium.org/11316230

9 files changed, 106 insertions, 60 deletions

diff --git a/include/llvm/ADT/Triple.h b/include/llvm/ADT/Triple.h
index a9e67cafba..f317c190b0 100644
--- a/include/llvm/ADT/Triple.h
+++ b/include/llvm/ADT/Triple.h
@@ -310,6 +310,11 @@ public:
     return getOS() == Triple::Win32 || isOSCygMing();
   }
 
+  /// \brief isOSNaCl - Is this the Native Client OS.
+  bool isOSNaCl() const {
+    return getOS() == Triple::NativeClient;
+  }
+
   /// \brief Tests whether the OS uses the ELF binary format.
   bool isOSBinFormatELF() const {
     return !isOSDarwin() && !isOSWindows();
diff --git a/lib/Target/ARM/ARMSubtarget.h b/lib/Target/ARM/ARMSubtarget.h
index e99d1d4a48..f07ad350a2 100644
--- a/lib/Target/ARM/ARMSubtarget.h
+++ b/lib/Target/ARM/ARMSubtarget.h
@@ -256,9 +256,7 @@ protected:
 
   bool isTargetIOS() const { return TargetTriple.getOS() == Triple::IOS; }
   bool isTargetDarwin() const { return TargetTriple.isOSDarwin(); }
-  bool isTargetNaCl() const {
-    return TargetTriple.getOS() == Triple::NativeClient;
-  }
+  bool isTargetNaCl() const { return TargetTriple.isOSNaCl(); }  // @LOCALMOD
   bool isTargetELF() const { return !isTargetDarwin(); }
 
   bool isAPCS_ABI() const { return TargetABI == ARM_ABI_APCS; }
diff --git a/lib/Target/ARM/MCTargetDesc/ARMAsmBackend.cpp b/lib/Target/ARM/MCTargetDesc/ARMAsmBackend.cpp
index 6380d09ad8..27c1bc76fd 100644
--- a/lib/Target/ARM/MCTargetDesc/ARMAsmBackend.cpp
+++ b/lib/Target/ARM/MCTargetDesc/ARMAsmBackend.cpp
@@ -632,20 +632,37 @@ public:
                    uint8_t _OSABI)
     : ARMAsmBackend(T, TT), OSABI(_OSABI) { }
 
+  void applyFixup(const MCFixup &Fixup, char *Data, unsigned DataSize,
+                  uint64_t Value) const;
+
   MCObjectWriter *createObjectWriter(raw_ostream &OS) const {
     return createARMELFObjectWriter(OS, OSABI);
   }
 };
 
+// FIXME: Raise this to share code between Darwin and ELF.
+void ELFARMAsmBackend::applyFixup(const MCFixup &Fixup, char *Data,
+                                  unsigned DataSize, uint64_t Value) const {
+  unsigned NumBytes = 4;        // FIXME: 2 for Thumb
+  Value = adjustFixupValue(Fixup, Value);
+  if (!Value) return;           // Doesn't change encoding.
+
+  unsigned Offset = Fixup.getOffset();
+
+  // For each byte of the fragment that the fixup touches, mask in the bits from
+  // the fixup value. The Value has been "split up" into the appropriate
+  // bitfields above.
+  for (unsigned i = 0; i != NumBytes; ++i)
+    Data[Offset + i] |= uint8_t((Value >> (i * 8)) & 0xff);
+}
+
 // @LOCALMOD-BEGIN
 class NaClARMAsmBackend : public ELFARMAsmBackend {
- public:
-  NaClARMAsmBackend(const Target &T, const StringRef TT,
-                    uint8_t OSABI)
-      : ELFARMAsmBackend(T, TT, OSABI) { }
-  unsigned getBundleSize() const {
-    return 16;
-  }
+public:
+  NaClARMAsmBackend(const Target &T, const StringRef TT, uint8_t _OSABI)
+    : ELFARMAsmBackend(T, TT, _OSABI) { }
+
+  unsigned getBundleSize() const { return 16; }
 
   bool CustomExpandInst(const MCInst &Inst, MCStreamer &Out) const {
     return CustomExpandInstNaClARM(Inst, Out);
@@ -705,7 +722,9 @@ MCAsmBackend *llvm::createARMAsmBackend(const Target &T, StringRef TT, StringRef
     assert(0 && "Windows not supported on ARM");
 
   uint8_t OSABI = MCELFObjectTargetWriter::getOSABI(Triple(TT).getOS());
-  if (TheTriple.getOS() == llvm::Triple::NativeClient)
+  // @LOCALMOD-END
+  if (TheTriple.isOSNaCl())
     return new NaClARMAsmBackend(T, TT, OSABI);
+  // @LOCALMOD-END
   return new ELFARMAsmBackend(T, TT, OSABI);
 }
diff --git a/lib/Target/ARM/MCTargetDesc/ARMMCTargetDesc.cpp b/lib/Target/ARM/MCTargetDesc/ARMMCTargetDesc.cpp
index ffbb115098..bb40b4b0de 100644
--- a/lib/Target/ARM/MCTargetDesc/ARMMCTargetDesc.cpp
+++ b/lib/Target/ARM/MCTargetDesc/ARMMCTargetDesc.cpp
@@ -156,7 +156,7 @@ static MCAsmInfo *createARMMCAsmInfo(const Target &T, StringRef TT) {
 
   // @LOCALMOD-BEGIN
   ARMELFMCAsmInfo *MAI = new ARMELFMCAsmInfo();
-  if (TheTriple.getOS() == Triple::NativeClient) {
+  if (TheTriple.isOSNaCl()) {
     // NativeClient uses Dwarf exception handling
     MAI->setExceptionsType(ExceptionHandling::DwarfCFI);
     // Initial state of the frame ARM:SP points to cfa
diff --git a/lib/Target/Mips/MCTargetDesc/MipsAsmBackend.cpp b/lib/Target/Mips/MCTargetDesc/MipsAsmBackend.cpp
index 2e5092c13c..f7e88b98f8 100644
--- a/lib/Target/Mips/MCTargetDesc/MipsAsmBackend.cpp
+++ b/lib/Target/Mips/MCTargetDesc/MipsAsmBackend.cpp
@@ -248,29 +248,36 @@ public:
       OW->Write32(0);
     return true;
   }
+}; // class MipsAsmBackend
+
+// @LOCALMOD-BEGIN
+class NaClMipsAsmBackend : public MipsAsmBackend {
+public:
+  NaClMipsAsmBackend(const Target &T, bool _is64Bit)
+    : MipsAsmBackend(T, Triple::NativeClient, /* IsLittle */ true, _is64Bit) {}
 
-  // @LOCALMOD-BEGIN
-  // FIXME! NaCl should INHERIT from MipsAsmBackend, not add to it.
   unsigned getBundleSize() const {
-    return (OSType == Triple::NativeClient) ? 16 : 0;
+    return 16;
   }
 
   bool CustomExpandInst(const MCInst &Inst, MCStreamer &Out) const {
-    if (OSType == Triple::NativeClient) {
-      return CustomExpandInstNaClMips(Inst, Out);
-    }
-    return false;
+    return CustomExpandInstNaClMips(Inst, Out);
   }
-  // @LOCALMOD-END
-}; // class MipsAsmBackend
+}; // class NaClMipsAsmBackend
+// @LOCALMOD-END
 
 } // namespace
 
 // MCAsmBackend
 MCAsmBackend *llvm::createMipsAsmBackendEL32(const Target &T, StringRef TT,
                                              StringRef CPU) {
-  return new MipsAsmBackend(T, Triple(TT).getOS(),
-                            /*IsLittle*/true, /*Is64Bit*/false);
+  // @LOCALMOD-BEGIN
+  if (Triple(TT).isOSNaCl())
+    return new NaClMipsAsmBackend(T, /*Is64Bit*/false);
+  else
+    return new MipsAsmBackend(T, Triple(TT).getOS(),
+                              /*IsLittle*/true, /*Is64Bit*/false);
+  // @LOCALMOD-END
 }
 
 MCAsmBackend *llvm::createMipsAsmBackendEB32(const Target &T, StringRef TT,
@@ -281,8 +288,13 @@ MCAsmBackend *llvm::createMipsAsmBackendEB32(const Target &T, StringRef TT,
 
 MCAsmBackend *llvm::createMipsAsmBackendEL64(const Target &T, StringRef TT,
                                              StringRef CPU) {
-  return new MipsAsmBackend(T, Triple(TT).getOS(),
-                            /*IsLittle*/true, /*Is64Bit*/true);
+  // @LOCALMOD-BEGIN
+  if (Triple(TT).isOSNaCl())
+    return new NaClMipsAsmBackend(T, /*Is64Bit*/true);
+  else
+    return new MipsAsmBackend(T, Triple(TT).getOS(),
+                              /*IsLittle*/true, /*Is64Bit*/true);
+  // @LOCALMOD-END
 }
 
 MCAsmBackend *llvm::createMipsAsmBackendEB64(const Target &T, StringRef TT,
diff --git a/lib/Target/Mips/MipsSubtarget.h b/lib/Target/Mips/MipsSubtarget.h
index 0ea85bb3c1..f8fd0490fa 100644
--- a/lib/Target/Mips/MipsSubtarget.h
+++ b/lib/Target/Mips/MipsSubtarget.h
@@ -157,11 +157,7 @@ public:
   bool hasBitCount()  const { return HasBitCount; }
   bool hasFPIdx()     const { return HasFPIdx; }
 
-  // @LOCALMOD-BEGIN
-  bool isTargetNaCl() const {
-    return TargetTriple.getOS() == Triple::NativeClient;
-  }
-  // @LOCALMOD-END
+  bool isTargetNaCl() const { return TargetTriple.isOSNaCl(); }  // @LOCALMOD
 
 };
 } // End llvm namespace
diff --git a/lib/Target/X86/MCTargetDesc/X86AsmBackend.cpp b/lib/Target/X86/MCTargetDesc/X86AsmBackend.cpp
index 2c91c8c566..c0bddc65c1 100644
--- a/lib/Target/X86/MCTargetDesc/X86AsmBackend.cpp
+++ b/lib/Target/X86/MCTargetDesc/X86AsmBackend.cpp
@@ -338,10 +338,8 @@ namespace {
 class ELFX86AsmBackend : public X86AsmBackend {
 public:
   uint8_t OSABI;
-  Triple::OSType OSType; // @LOCALMOD: kept OSTYPE vs upstream. FIXME: remove.
-  ELFX86AsmBackend(const Target &T, uint8_t _OSABI, StringRef CPU,
-                   Triple::OSType _OSType)
-    : X86AsmBackend(T, CPU), OSABI(_OSABI), OSType(_OSType) {
+  ELFX86AsmBackend(const Target &T, uint8_t _OSABI, StringRef CPU)
+    : X86AsmBackend(T, CPU), OSABI(_OSABI) {
     HasReliableSymbolDifference = true;
   }
 
@@ -350,27 +348,12 @@ public:
     return ES.getFlags() & ELF::SHF_MERGE;
   }
 
-  // @LOCALMOD-BEGIN
-  // FIXME! NaCl should inherit from ELFX86AsmBackend!
-  unsigned getBundleSize() const {
-    return OSType == Triple::NativeClient ? 32 : 0;
-  }
-
-  bool CustomExpandInst(const MCInst &Inst, MCStreamer &Out) const {
-    if (OSType == Triple::NativeClient) {
-      return CustomExpandInstNaClX86(Inst, Out);
-    }
-    return false;
-  }
-  // @LOCALMOD-END
-
 };
 
 class ELFX86_32AsmBackend : public ELFX86AsmBackend {
 public:
-  ELFX86_32AsmBackend(const Target &T, uint8_t OSABI, StringRef CPU,
-                      Triple::OSType OSType) // @LOCALMOD: kept OSType
-    : ELFX86AsmBackend(T, OSABI, CPU, OSType) {}
+  ELFX86_32AsmBackend(const Target &T, uint8_t OSABI, StringRef CPU)
+    : ELFX86AsmBackend(T, OSABI, CPU) {}
 
   MCObjectWriter *createObjectWriter(raw_ostream &OS) const {
     return createX86ELFObjectWriter(OS, /*IsELF64*/ false, OSABI, ELF::EM_386);
@@ -379,15 +362,40 @@ public:
 
 class ELFX86_64AsmBackend : public ELFX86AsmBackend {
 public:
-  ELFX86_64AsmBackend(const Target &T, uint8_t OSABI, StringRef CPU,
-                      Triple::OSType OSType) // @LOCALMOD: kept OSType
-    : ELFX86AsmBackend(T, OSABI, CPU, OSType) {}
+  ELFX86_64AsmBackend(const Target &T, uint8_t OSABI, StringRef CPU)
+    : ELFX86AsmBackend(T, OSABI, CPU) {}
 
   MCObjectWriter *createObjectWriter(raw_ostream &OS) const {
     return createX86ELFObjectWriter(OS, /*IsELF64*/ true, OSABI, ELF::EM_X86_64);
   }
 };
 
+// @LOCALMOD-BEGIN
+class NaClX86_32AsmBackend : public ELFX86_32AsmBackend {
+public:
+  NaClX86_32AsmBackend(const Target &T, uint8_t OSABI, StringRef CPU)
+    : ELFX86_32AsmBackend(T, OSABI, CPU) {}
+
+  unsigned getBundleSize() const { return 32; }
+
+  bool CustomExpandInst(const MCInst &Inst, MCStreamer &Out) const {
+    return CustomExpandInstNaClX86(Inst, Out);
+  }
+};
+
+class NaClX86_64AsmBackend : public ELFX86_64AsmBackend {
+public:
+  NaClX86_64AsmBackend(const Target &T, uint8_t OSABI, StringRef CPU)
+    : ELFX86_64AsmBackend(T, OSABI, CPU) {}
+
+  unsigned getBundleSize() const { return 32; }
+
+  bool CustomExpandInst(const MCInst &Inst, MCStreamer &Out) const {
+    return CustomExpandInstNaClX86(Inst, Out);
+  }
+};
+// @LOCALMOD-END
+
 class WindowsX86AsmBackend : public X86AsmBackend {
   bool Is64Bit;
 
@@ -479,7 +487,12 @@ MCAsmBackend *llvm::createX86_32AsmBackend(const Target &T, StringRef TT, String
     return new WindowsX86AsmBackend(T, false, CPU);
 
   uint8_t OSABI = MCELFObjectTargetWriter::getOSABI(TheTriple.getOS());
-  return new ELFX86_32AsmBackend(T, OSABI, CPU, TheTriple.getOS());
+  // @LOCALMOD-BEGIN
+  if (TheTriple.isOSNaCl())
+    return new NaClX86_32AsmBackend(T, OSABI, CPU);
+  else
+    return new ELFX86_32AsmBackend(T, OSABI, CPU);
+  // @LOCALMOD-END
 }
 
 MCAsmBackend *llvm::createX86_64AsmBackend(const Target &T, StringRef TT, StringRef CPU) {
@@ -492,5 +505,10 @@ MCAsmBackend *llvm::createX86_64AsmBackend(const Target &T, StringRef TT, String
     return new WindowsX86AsmBackend(T, true, CPU);
 
   uint8_t OSABI = MCELFObjectTargetWriter::getOSABI(TheTriple.getOS());
-  return new ELFX86_64AsmBackend(T, OSABI, CPU, TheTriple.getOS());
+  // @LOCALMOD-BEGIN
+  if (TheTriple.isOSNaCl())
+    return new NaClX86_64AsmBackend(T, OSABI, CPU);
+  else
+    return new ELFX86_64AsmBackend(T, OSABI, CPU);
+  // @LOCALMOD-END
 }
diff --git a/lib/Target/X86/MCTargetDesc/X86MCAsmInfo.cpp b/lib/Target/X86/MCTargetDesc/X86MCAsmInfo.cpp
index 7706b9308e..19951b3385 100644
--- a/lib/Target/X86/MCTargetDesc/X86MCAsmInfo.cpp
+++ b/lib/Target/X86/MCTargetDesc/X86MCAsmInfo.cpp
@@ -79,7 +79,7 @@ X86ELFMCAsmInfo::X86ELFMCAsmInfo(const Triple &T) {
 
   // @LOCALMOD-BEGIN
   if (T.getArch() == Triple::x86_64) {
-    if (T.getOS() == Triple::NativeClient) {
+    if (T.isOSNaCl()) {
       PointerSize = 4;
       StackSlotSize = 8;
     } else {
diff --git a/lib/Target/X86/X86Subtarget.h b/lib/Target/X86/X86Subtarget.h
index 0f8cab52f2..f86b947574 100644
--- a/lib/Target/X86/X86Subtarget.h
+++ b/lib/Target/X86/X86Subtarget.h
@@ -249,9 +249,7 @@ public:
             TargetTriple.isOSBinFormatELF());
   }
   bool isTargetLinux() const { return TargetTriple.getOS() == Triple::Linux; }
-  bool isTargetNaCl() const {
-    return TargetTriple.getOS() == Triple::NativeClient;
-  }
+  bool isTargetNaCl() const { return TargetTriple.isOSNaCl(); }  // @LOCALMOD
   bool isTargetNaCl32() const { return isTargetNaCl() && !is64Bit(); }
   bool isTargetNaCl64() const { return isTargetNaCl() && is64Bit(); }
   bool isTargetWindows() const { return TargetTriple.getOS() == Triple::Win32; }