1 files changed, 26 insertions, 20 deletions

diff --git a/lib/Target/X86/MCTargetDesc/X86AsmBackend.cpp b/lib/Target/X86/MCTargetDesc/X86AsmBackend.cpp
index bf30a8e..23bca0d 100644
--- a/lib/Target/X86/MCTargetDesc/X86AsmBackend.cpp
+++ b/lib/Target/X86/MCTargetDesc/X86AsmBackend.cpp
@@ -73,11 +73,12 @@ public:
 };
 
 class X86AsmBackend : public MCAsmBackend {
-  StringRef CPU;
+  const StringRef CPU;
   bool HasNopl;
+  const uint64_t MaxNopLength;
 public:
   X86AsmBackend(const Target &T, StringRef _CPU)
-    : MCAsmBackend(), CPU(_CPU) {
+    : MCAsmBackend(), CPU(_CPU), MaxNopLength(_CPU == "slm" ? 7 : 15) {
     HasNopl = CPU != "generic" && CPU != "i386" && CPU != "i486" &&
               CPU != "i586" && CPU != "pentium" && CPU != "pentium-mmx" &&
               CPU != "i686" && CPU != "k6" && CPU != "k6-2" && CPU != "k6-3" &&
@@ -331,7 +332,7 @@ bool X86AsmBackend::writeNopData(uint64_t Count, MCObjectWriter *OW) const {
   // 15 is the longest single nop instruction.  Emit as many 15-byte nops as
   // needed, then emit a nop of the remaining length.
   do {
-    const uint8_t ThisNopLength = (uint8_t) std::min(Count, (uint64_t) 15);
+    const uint8_t ThisNopLength = (uint8_t) std::min(Count, MaxNopLength);
     const uint8_t Prefixes = ThisNopLength <= 10 ? 0 : ThisNopLength - 10;
     for (uint8_t i = 0; i < Prefixes; i++)
       OW->Write8(0x66);
@@ -365,6 +366,17 @@ public:
   }
 };
 
+class ELFX86_X32AsmBackend : public ELFX86AsmBackend {
+public:
+  ELFX86_X32AsmBackend(const Target &T, uint8_t OSABI, StringRef CPU)
+      : ELFX86AsmBackend(T, OSABI, CPU) {}
+
+  MCObjectWriter *createObjectWriter(raw_ostream &OS) const override {
+    return createX86ELFObjectWriter(OS, /*IsELF64*/ false, OSABI,
+                                    ELF::EM_X86_64);
+  }
+};
+
 class ELFX86_64AsmBackend : public ELFX86AsmBackend {
 public:
   ELFX86_64AsmBackend(const Target &T, uint8_t OSABI, StringRef CPU)
@@ -717,11 +729,10 @@ public:
 };
 
 class DarwinX86_32AsmBackend : public DarwinX86AsmBackend {
-  bool SupportsCU;
 public:
   DarwinX86_32AsmBackend(const Target &T, const MCRegisterInfo &MRI,
-                         StringRef CPU, bool SupportsCU)
-    : DarwinX86AsmBackend(T, MRI, CPU, false), SupportsCU(SupportsCU) {}
+                         StringRef CPU)
+      : DarwinX86AsmBackend(T, MRI, CPU, false) {}
 
   MCObjectWriter *createObjectWriter(raw_ostream &OS) const override {
     return createX86MachObjectWriter(OS, /*Is64Bit=*/false,
@@ -732,20 +743,16 @@ public:
   /// \brief Generate the compact unwind encoding for the CFI instructions.
   uint32_t generateCompactUnwindEncoding(
                              ArrayRef<MCCFIInstruction> Instrs) const override {
-    return SupportsCU ? generateCompactUnwindEncodingImpl(Instrs) : 0;
+    return generateCompactUnwindEncodingImpl(Instrs);
   }
 };
 
 class DarwinX86_64AsmBackend : public DarwinX86AsmBackend {
-  bool SupportsCU;
   const MachO::CPUSubTypeX86 Subtype;
 public:
   DarwinX86_64AsmBackend(const Target &T, const MCRegisterInfo &MRI,
-                         StringRef CPU, bool SupportsCU,
-                         MachO::CPUSubTypeX86 st)
-    : DarwinX86AsmBackend(T, MRI, CPU, true), SupportsCU(SupportsCU),
-      Subtype(st) {
-  }
+                         StringRef CPU, MachO::CPUSubTypeX86 st)
+      : DarwinX86AsmBackend(T, MRI, CPU, true), Subtype(st) {}
 
   MCObjectWriter *createObjectWriter(raw_ostream &OS) const override {
     return createX86MachObjectWriter(OS, /*Is64Bit=*/true,
@@ -788,7 +795,7 @@ public:
   /// \brief Generate the compact unwind encoding for the CFI instructions.
   uint32_t generateCompactUnwindEncoding(
                              ArrayRef<MCCFIInstruction> Instrs) const override {
-    return SupportsCU ? generateCompactUnwindEncodingImpl(Instrs) : 0;
+    return generateCompactUnwindEncodingImpl(Instrs);
   }
 };
 
@@ -801,9 +808,7 @@ MCAsmBackend *llvm::createX86_32AsmBackend(const Target &T,
   Triple TheTriple(TT);
 
   if (TheTriple.isOSBinFormatMachO())
-    return new DarwinX86_32AsmBackend(T, MRI, CPU,
-                                      TheTriple.isMacOSX() &&
-                                      !TheTriple.isMacOSXVersionLT(10, 7));
+    return new DarwinX86_32AsmBackend(T, MRI, CPU);
 
   if (TheTriple.isOSWindows() && !TheTriple.isOSBinFormatELF())
     return new WindowsX86AsmBackend(T, false, CPU);
@@ -823,14 +828,15 @@ MCAsmBackend *llvm::createX86_64AsmBackend(const Target &T,
         StringSwitch<MachO::CPUSubTypeX86>(TheTriple.getArchName())
             .Case("x86_64h", MachO::CPU_SUBTYPE_X86_64_H)
             .Default(MachO::CPU_SUBTYPE_X86_64_ALL);
-    return new DarwinX86_64AsmBackend(T, MRI, CPU,
-                                      TheTriple.isMacOSX() &&
-                                      !TheTriple.isMacOSXVersionLT(10, 7), CS);
+    return new DarwinX86_64AsmBackend(T, MRI, CPU, CS);
   }
 
   if (TheTriple.isOSWindows() && !TheTriple.isOSBinFormatELF())
     return new WindowsX86AsmBackend(T, true, CPU);
 
   uint8_t OSABI = MCELFObjectTargetWriter::getOSABI(TheTriple.getOS());
+
+  if (TheTriple.getEnvironment() == Triple::GNUX32)
+    return new ELFX86_X32AsmBackend(T, OSABI, CPU);
   return new ELFX86_64AsmBackend(T, OSABI, CPU);
 }