This patch implements runtime Mips specific

setting of ELF header e_flags.

Contributer: Jack Carter
 


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173884 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Target/Mips/MCTargetDesc/MipsELFStreamer.cpp

@@ -0,0 +1,61 @@
+//===-- MipsELFStreamer.cpp - MipsELFStreamer ---------------------------===//
+//
+//                       The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===-------------------------------------------------------------------===//
+#include "MCTargetDesc/MipsELFStreamer.h"
+#include "MipsSubtarget.h"
+#include "llvm/MC/MCAssembler.h"
+#include "llvm/Support/ELF.h"
+#include "llvm/Support/ErrorHandling.h"
+
+namespace llvm {
+
+  MCELFStreamer* createMipsELFStreamer(MCContext &Context, MCAsmBackend &TAB,
+                                       raw_ostream &OS, MCCodeEmitter *Emitter,
+                                       bool RelaxAll, bool NoExecStack) {
+    MipsELFStreamer *S = new MipsELFStreamer(Context, TAB, OS, Emitter,
+                                             RelaxAll, NoExecStack);
+    return S;
+  }
+
+  // For llc. Set a group of ELF header flags
+  void
+  MipsELFStreamer::emitELFHeaderFlagsCG(const MipsSubtarget &Subtarget) {
+
+    if (hasRawTextSupport())
+      return;
+
+    // Update e_header flags
+    MCAssembler& MCA = getAssembler();
+    unsigned EFlags = MCA.getELFHeaderEFlags();
+
+    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;
+
+    // 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");
+
+    MCA.setELFHeaderEFlags(EFlags);
+
+
+  }
+}

lib/Target/Mips/MCTargetDesc/MipsELFStreamer.h

@@ -0,0 +1,37 @@
+//=== MipsELFStreamer.h - MipsELFStreamer ------------------------------===//
+//
+//                    The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENCE.TXT for details.
+//
+//===-------------------------------------------------------------------===//
+#ifndef MIPSELFSTREAMER_H_
+#define MIPSELFSTREAMER_H_
+
+#include "llvm/MC/MCELFStreamer.h"
+
+namespace llvm {
+class MipsSubtarget;
+
+class MipsELFStreamer : public MCELFStreamer {
+private:
+  unsigned EFlags;
+public:
+  MipsELFStreamer(MCContext &Context, MCAsmBackend &TAB,
+                  raw_ostream &OS, MCCodeEmitter *Emitter,
+                  bool RelaxAll, bool NoExecStack)
+    : MCELFStreamer(Context, TAB, OS, Emitter), EFlags(0) {
+  }
+
+  ~MipsELFStreamer() {}
+  void emitELFHeaderFlagsCG(const MipsSubtarget &Subtarget);
+//  void emitELFHeaderFlagCG(unsigned Val);
+};
+
+  MCELFStreamer* createMipsELFStreamer(MCContext &Context, MCAsmBackend &TAB,
+                                       raw_ostream &OS, MCCodeEmitter *Emitter,
+                                       bool RelaxAll, bool NoExecStack);
+}
+
+#endif /* MIPSELFSTREAMER_H_ */

lib/Target/Mips/MCTargetDesc/MipsMCTargetDesc.cpp

@@ -11,6 +11,7 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "MCTargetDesc/MipsELFStreamer.h"
 #include "MipsMCTargetDesc.h"
 #include "InstPrinter/MipsInstPrinter.h"
 #include "MipsMCAsmInfo.h"
@@ -131,7 +132,7 @@ static MCStreamer *createMCStreamer(const Target &T, StringRef TT,
                                     bool NoExecStack) {
   Triple TheTriple(TT);
 
-  return createELFStreamer(Ctx, MAB, _OS, _Emitter, RelaxAll, NoExecStack);
+  return createMipsELFStreamer(Ctx, MAB, _OS, _Emitter, RelaxAll, NoExecStack);
 }
 
 extern "C" void LLVMInitializeMipsTargetMC() {

lib/Target/Mips/MipsAsmPrinter.cpp

@@ -15,6 +15,7 @@
 #define DEBUG_TYPE "mips-asm-printer"
 #include "InstPrinter/MipsInstPrinter.h"
 #include "MCTargetDesc/MipsBaseInfo.h"
+#include "MCTargetDesc/MipsELFStreamer.h"
 #include "Mips.h"
 #include "MipsAsmPrinter.h"
 #include "MipsInstrInfo.h"
@@ -545,9 +546,13 @@ void MipsAsmPrinter::EmitStartOfAsmFile(Module &M) {
 
 void MipsAsmPrinter::EmitEndOfAsmFile(Module &M) {
 
+  if (OutStreamer.hasRawTextSupport()) return;
+
   // Emit Mips ELF register info
   Subtarget->getMReginfo().emitMipsReginfoSectionCG(
              OutStreamer, getObjFileLowering(), *Subtarget);
+  MipsELFStreamer & MES = static_cast<MipsELFStreamer &>(OutStreamer);
+  MES.emitELFHeaderFlagsCG(*Subtarget);
 }
 
 MachineLocation

lib/Target/Mips/MipsSubtarget.cpp

@@ -26,13 +26,13 @@ void MipsSubtarget::anchor() { }
 
 MipsSubtarget::MipsSubtarget(const std::string &TT, const std::string &CPU,
                              const std::string &FS, bool little,
-                             Reloc::Model RM) :
+                             Reloc::Model _RM) :
   MipsGenSubtargetInfo(TT, CPU, FS),
   MipsArchVersion(Mips32), MipsABI(UnknownABI), IsLittle(little),
   IsSingleFloat(false), IsFP64bit(false), IsGP64bit(false), HasVFPU(false),
   IsLinux(true), HasSEInReg(false), HasCondMov(false), HasSwap(false),
   HasBitCount(false), HasFPIdx(false),
-  InMips16Mode(false), HasDSP(false), HasDSPR2(false), IsAndroid(false)
+  InMips16Mode(false), HasDSP(false), HasDSPR2(false), IsAndroid(false), RM(_RM)
 {
   std::string CPUName = CPU;
   if (CPUName.empty())

lib/Target/Mips/MipsSubtarget.h

@@ -100,6 +100,9 @@ protected:
   // The instance to the register info section object
   MipsReginfo MRI;
 
+  // Relocation Model
+  Reloc::Model RM;
+
 public:
   virtual bool enablePostRAScheduler(CodeGenOpt::Level OptLevel,
                                      AntiDepBreakMode& Mode,
@@ -152,6 +155,9 @@ public:
 
   // Grab MipsRegInfo object
   const MipsReginfo &getMReginfo() const { return MRI; }
+
+  // Grab relocation model
+  Reloc::Model getRelocationModel() const {return RM;}
 };
 } // End llvm namespace
 

test/MC/Mips/elf_eflags.ll

@@ -0,0 +1,55 @@
+; This tests ELF EFLAGS setting with direct object.
+; When the assembler is ready a .s file for it will
+; be created.
+
+; Non-shared (static) is the absence of pic and or cpic.
+
+; EF_MIPS_NOREORDER (0x00000001) is always on by default currently
+; EF_MIPS_PIC (0x00000002)
+; EF_MIPS_CPIC (0x00000004) - not tested yet
+; EF_MIPS_ABI2 (0x00000020) - n32 not tested yet
+; EF_MIPS_ARCH_32 (0x50000000)
+; EF_MIPS_ARCH_64 (0x60000000)
+; EF_MIPS_ARCH_32R2 (0x70000000)
+; EF_MIPS_ARCH_64R2 (0x80000000)
+
+; RUN: llc -filetype=obj -mtriple mipsel-unknown-linux -mcpu=mips32 -relocation-model=static %s -o - | elf-dump --dump-section-data  | FileCheck -check-prefix=CHECK-BE32 %s
+; RUN: llc -filetype=obj -mtriple mipsel-unknown-linux -mcpu=mips32 %s -o - | elf-dump --dump-section-data  | FileCheck -check-prefix=CHECK-BE32_PIC %s
+; RUN: llc -filetype=obj -mtriple mipsel-unknown-linux -mcpu=mips32r2 -relocation-model=static %s -o - | elf-dump --dump-section-data  | FileCheck -check-prefix=CHECK-BE32R2 %s
+; RUN: llc -filetype=obj -mtriple mipsel-unknown-linux -mcpu=mips32r2 %s -o - | elf-dump --dump-section-data  | FileCheck -check-prefix=CHECK-BE32R2_PIC %s
+
+; RUN: llc -filetype=obj -mtriple mipsel-unknown-linux -mcpu=mips64 -relocation-model=static %s -o - | elf-dump --dump-section-data  | FileCheck -check-prefix=CHECK-BE64 %s
+; RUN: llc -filetype=obj -mtriple mipsel-unknown-linux -mcpu=mips64 %s -o - | elf-dump --dump-section-data  | FileCheck -check-prefix=CHECK-BE64_PIC %s
+; RUN: llc -filetype=obj -mtriple mipsel-unknown-linux -mcpu=mips64r2 -relocation-model=static %s -o - | elf-dump --dump-section-data  | FileCheck -check-prefix=CHECK-BE64R2 %s
+; RUN: llc -filetype=obj -mtriple mipsel-unknown-linux -mcpu=mips64r2 %s -o - | elf-dump --dump-section-data  | FileCheck -check-prefix=CHECK-BE64R2_PIC %s
+
+
+; 32(R1) bit with NO_REORDER and static
+; CHECK-BE32: ('e_flags', 0x50000001)
+;
+; 32(R1) bit with NO_REORDER and PIC
+; CHECK-BE32_PIC: ('e_flags', 0x50000003)
+;
+; 32R2 bit with NO_REORDER and static
+; CHECK-BE32R2: ('e_flags', 0x70000001)
+;
+; 32R2 bit with NO_REORDER and PIC
+; CHECK-BE32R2_PIC: ('e_flags', 0x70000003)
+;
+; 64(R1) bit with NO_REORDER and static
+; CHECK-BE64: ('e_flags', 0x60000001)
+;
+; 64(R1) bit with NO_REORDER and PIC
+; CHECK-BE64_PIC: ('e_flags', 0x60000003)
+;
+; 64R2 bit with NO_REORDER and static
+; CHECK-BE64R2: ('e_flags', 0x80000001)
+;
+; 64R2 bit with NO_REORDER and PIC
+; CHECK-BE64R2_PIC: ('e_flags', 0x80000003)
+;
+
+define i32 @main() nounwind {
+entry:
+  ret i32 0
+}