[Hexagon] Adding MC ELF streamer and updating addend relocation test which shows correct ELF symbol.

llvm-svn: 239876
diff --git a/llvm/lib/Target/Hexagon/MCTargetDesc/HexagonMCELFStreamer.cpp b/llvm/lib/Target/Hexagon/MCTargetDesc/HexagonMCELFStreamer.cpp
new file mode 100644
index 0000000..bf51c35
--- /dev/null
+++ b/llvm/lib/Target/Hexagon/MCTargetDesc/HexagonMCELFStreamer.cpp
@@ -0,0 +1,152 @@
+//=== HexagonMCELFStreamer.cpp - Hexagon subclass of MCELFStreamer -------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file is a stub that parses a MCInst bundle and passes the
+// instructions on to the real streamer.
+//
+//===----------------------------------------------------------------------===//
+#define DEBUG_TYPE "hexagonmcelfstreamer"
+
+#include "Hexagon.h"
+#include "HexagonMCELFStreamer.h"
+#include "MCTargetDesc/HexagonBaseInfo.h"
+#include "MCTargetDesc/HexagonMCShuffler.h"
+#include "llvm/ADT/StringExtras.h"
+#include "llvm/MC/MCAssembler.h"
+#include "llvm/MC/MCContext.h"
+#include "llvm/MC/MCSectionELF.h"
+#include "llvm/MC/MCStreamer.h"
+#include "llvm/MC/MCSymbol.h"
+#include "llvm/MC/MCSymbolELF.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/raw_ostream.h"
+
+using namespace llvm;
+
+static cl::opt<unsigned>
+    GPSize("gpsize", cl::NotHidden,
+           cl::desc("Global Pointer Addressing Size.  The default size is 8."),
+           cl::Prefix, cl::init(8));
+
+void HexagonMCELFStreamer::EmitInstruction(const MCInst &MCK,
+                                           const MCSubtargetInfo &STI) {
+  MCInst HMI;
+  HMI.setOpcode(Hexagon::BUNDLE);
+  HMI.addOperand(MCOperand::createImm(0));
+  MCInst *MCB;
+
+  if (MCK.getOpcode() != Hexagon::BUNDLE) {
+    HMI.addOperand(MCOperand::createInst(&MCK));
+    MCB = &HMI;
+  } else
+    MCB = const_cast<MCInst *>(&MCK);
+
+  // Examines packet and pad the packet, if needed, when an
+  // end-loop is in the bundle.
+  HexagonMCInstrInfo::padEndloop(*MCB);
+  HexagonMCShuffle(*MCII, STI, *MCB);
+
+  assert(HexagonMCInstrInfo::bundleSize(*MCB) <= HEXAGON_PACKET_SIZE);
+  bool Extended = false;
+  for (auto &I : HexagonMCInstrInfo::bundleInstructions(*MCB)) {
+    MCInst *MCI = const_cast<MCInst *>(I.getInst());
+    if (Extended) {
+      if (HexagonMCInstrInfo::isDuplex(*MCII, *MCI)) {
+        MCInst *SubInst = const_cast<MCInst *>(MCI->getOperand(1).getInst());
+        HexagonMCInstrInfo::clampExtended(*MCII, *SubInst);
+      } else {
+        HexagonMCInstrInfo::clampExtended(*MCII, *MCI);
+      }
+      Extended = false;
+    } else {
+      Extended = HexagonMCInstrInfo::isImmext(*MCI);
+    }
+  }
+
+  // At this point, MCB is a bundle
+  // Iterate through the bundle and assign addends for the instructions
+  for (auto const &I : HexagonMCInstrInfo::bundleInstructions(*MCB)) {
+    MCInst *MCI = const_cast<MCInst *>(I.getInst());
+    EmitSymbol(*MCI);
+  }
+  MCObjectStreamer::EmitInstruction(*MCB, STI);
+}
+
+void HexagonMCELFStreamer::EmitSymbol(const MCInst &Inst) {
+  // Scan for values.
+  for (unsigned i = Inst.getNumOperands(); i--;)
+    if (Inst.getOperand(i).isExpr())
+      visitUsedExpr(*Inst.getOperand(i).getExpr());
+}
+
+// EmitCommonSymbol and EmitLocalCommonSymbol are extended versions of the
+// functions found in MCELFStreamer.cpp taking AccessSize as an additional
+// parameter.
+void HexagonMCELFStreamer::HexagonMCEmitCommonSymbol(MCSymbol *Symbol,
+                                                     uint64_t Size,
+                                                     unsigned ByteAlignment,
+                                                     unsigned AccessSize) {
+  getAssembler().registerSymbol(*Symbol);
+  StringRef sbss[4] = {".sbss.1", ".sbss.2", ".sbss.4", ".sbss.8"};
+
+  auto ELFSymbol = cast<MCSymbolELF>(Symbol);
+  if (!ELFSymbol->isBindingSet()) {
+    ELFSymbol->setBinding(ELF::STB_GLOBAL);
+    ELFSymbol->setExternal(true);
+  }
+
+  ELFSymbol->setType(ELF::STT_OBJECT);
+
+  if (ELFSymbol->getBinding() == ELF::STB_LOCAL) {
+    StringRef SectionName =
+        ((AccessSize == 0) || (Size == 0) || (Size > GPSize))
+            ? ".bss"
+            : sbss[(Log2_64(AccessSize))];
+
+    MCSection *CrntSection = getCurrentSection().first;
+    MCSection *Section = getAssembler().getContext().getELFSection(
+        SectionName, ELF::SHT_NOBITS, ELF::SHF_WRITE | ELF::SHF_ALLOC);
+    SwitchSection(Section);
+    AssignSection(Symbol, Section);
+
+    MCELFStreamer::EmitCommonSymbol(Symbol, Size, ByteAlignment);
+    SwitchSection(CrntSection);
+  } else {
+    if (ELFSymbol->declareCommon(Size, ByteAlignment))
+      report_fatal_error("Symbol: " + Symbol->getName() +
+                         " redeclared as different type");
+    if ((AccessSize) && (Size <= GPSize)) {
+      uint64_t SectionIndex =
+          (AccessSize <= GPSize)
+              ? ELF::SHN_HEXAGON_SCOMMON + (Log2_64(AccessSize) + 1)
+              : (unsigned)ELF::SHN_HEXAGON_SCOMMON;
+      ELFSymbol->setIndex(SectionIndex);
+    }
+  }
+
+  ELFSymbol->setSize(MCConstantExpr::create(Size, getContext()));
+}
+
+void HexagonMCELFStreamer::HexagonMCEmitLocalCommonSymbol(
+    MCSymbol *Symbol, uint64_t Size, unsigned ByteAlignment,
+    unsigned AccessSize) {
+  getAssembler().registerSymbol(*Symbol);
+  auto ELFSymbol = cast<MCSymbolELF>(Symbol);
+  ELFSymbol->setBinding(ELF::STB_LOCAL);
+  ELFSymbol->setExternal(false);
+  HexagonMCEmitCommonSymbol(Symbol, Size, ByteAlignment, AccessSize);
+}
+
+namespace llvm {
+MCStreamer *createHexagonELFStreamer(MCContext &Context, MCAsmBackend &MAB,
+                                     raw_pwrite_stream &OS, MCCodeEmitter *CE) {
+  return new HexagonMCELFStreamer(Context, MAB, OS, CE);
+}
+}