1 files changed, 229 insertions, 0 deletions

diff --git a/contrib/llvm-project/llvm/lib/MC/MCWasmStreamer.cpp b/contrib/llvm-project/llvm/lib/MC/MCWasmStreamer.cpp
new file mode 100644
index 000000000000..86fa72197855
--- /dev/null
+++ b/contrib/llvm-project/llvm/lib/MC/MCWasmStreamer.cpp
@@ -0,0 +1,229 @@
+//===- lib/MC/MCWasmStreamer.cpp - Wasm Object Output ---------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file assembles .s files and emits Wasm .o object files.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/MC/MCWasmStreamer.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/SmallPtrSet.h"
+#include "llvm/MC/MCAsmBackend.h"
+#include "llvm/MC/MCAsmLayout.h"
+#include "llvm/MC/MCAssembler.h"
+#include "llvm/MC/MCCodeEmitter.h"
+#include "llvm/MC/MCContext.h"
+#include "llvm/MC/MCExpr.h"
+#include "llvm/MC/MCInst.h"
+#include "llvm/MC/MCObjectStreamer.h"
+#include "llvm/MC/MCSection.h"
+#include "llvm/MC/MCSectionWasm.h"
+#include "llvm/MC/MCSymbol.h"
+#include "llvm/MC/MCSymbolWasm.h"
+#include "llvm/MC/MCValue.h"
+#include "llvm/Support/Casting.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/TargetRegistry.h"
+#include "llvm/Support/raw_ostream.h"
+
+using namespace llvm;
+
+MCWasmStreamer::~MCWasmStreamer() = default; // anchor.
+
+void MCWasmStreamer::mergeFragment(MCDataFragment *DF, MCDataFragment *EF) {
+  flushPendingLabels(DF, DF->getContents().size());
+
+  for (unsigned I = 0, E = EF->getFixups().size(); I != E; ++I) {
+    EF->getFixups()[I].setOffset(EF->getFixups()[I].getOffset() +
+                                 DF->getContents().size());
+    DF->getFixups().push_back(EF->getFixups()[I]);
+  }
+  if (DF->getSubtargetInfo() == nullptr && EF->getSubtargetInfo())
+    DF->setHasInstructions(*EF->getSubtargetInfo());
+  DF->getContents().append(EF->getContents().begin(), EF->getContents().end());
+}
+
+void MCWasmStreamer::EmitAssemblerFlag(MCAssemblerFlag Flag) {
+  // Let the target do whatever target specific stuff it needs to do.
+  getAssembler().getBackend().handleAssemblerFlag(Flag);
+
+  // Do any generic stuff we need to do.
+  llvm_unreachable("invalid assembler flag!");
+}
+
+void MCWasmStreamer::ChangeSection(MCSection *Section,
+                                   const MCExpr *Subsection) {
+  MCAssembler &Asm = getAssembler();
+  auto *SectionWasm = cast<MCSectionWasm>(Section);
+  const MCSymbol *Grp = SectionWasm->getGroup();
+  if (Grp)
+    Asm.registerSymbol(*Grp);
+
+  this->MCObjectStreamer::ChangeSection(Section, Subsection);
+  Asm.registerSymbol(*Section->getBeginSymbol());
+}
+
+void MCWasmStreamer::EmitWeakReference(MCSymbol *Alias,
+                                       const MCSymbol *Symbol) {
+  getAssembler().registerSymbol(*Symbol);
+  const MCExpr *Value = MCSymbolRefExpr::create(
+      Symbol, MCSymbolRefExpr::VK_WEAKREF, getContext());
+  Alias->setVariableValue(Value);
+}
+
+bool MCWasmStreamer::EmitSymbolAttribute(MCSymbol *S, MCSymbolAttr Attribute) {
+  assert(Attribute != MCSA_IndirectSymbol && "indirect symbols not supported");
+
+  auto *Symbol = cast<MCSymbolWasm>(S);
+
+  // Adding a symbol attribute always introduces the symbol; note that an
+  // important side effect of calling registerSymbol here is to register the
+  // symbol with the assembler.
+  getAssembler().registerSymbol(*Symbol);
+
+  switch (Attribute) {
+  case MCSA_LazyReference:
+  case MCSA_Reference:
+  case MCSA_SymbolResolver:
+  case MCSA_PrivateExtern:
+  case MCSA_WeakDefinition:
+  case MCSA_WeakDefAutoPrivate:
+  case MCSA_Invalid:
+  case MCSA_IndirectSymbol:
+  case MCSA_Protected:
+    return false;
+
+  case MCSA_Hidden:
+    Symbol->setHidden(true);
+    break;
+
+  case MCSA_Weak:
+  case MCSA_WeakReference:
+    Symbol->setWeak(true);
+    Symbol->setExternal(true);
+    break;
+
+  case MCSA_Global:
+    Symbol->setExternal(true);
+    break;
+
+  case MCSA_ELF_TypeFunction:
+    Symbol->setType(wasm::WASM_SYMBOL_TYPE_FUNCTION);
+    break;
+
+  case MCSA_ELF_TypeObject:
+  case MCSA_Cold:
+    break;
+
+  case MCSA_NoDeadStrip:
+    Symbol->setExported();
+    break;
+
+  default:
+    // unrecognized directive
+    llvm_unreachable("unexpected MCSymbolAttr");
+    return false;
+  }
+
+  return true;
+}
+
+void MCWasmStreamer::EmitCommonSymbol(MCSymbol *S, uint64_t Size,
+                                      unsigned ByteAlignment) {
+  llvm_unreachable("Common symbols are not yet implemented for Wasm");
+}
+
+void MCWasmStreamer::emitELFSize(MCSymbol *Symbol, const MCExpr *Value) {
+  cast<MCSymbolWasm>(Symbol)->setSize(Value);
+}
+
+void MCWasmStreamer::EmitLocalCommonSymbol(MCSymbol *S, uint64_t Size,
+                                           unsigned ByteAlignment) {
+  llvm_unreachable("Local common symbols are not yet implemented for Wasm");
+}
+
+void MCWasmStreamer::EmitValueImpl(const MCExpr *Value, unsigned Size,
+                                   SMLoc Loc) {
+  MCObjectStreamer::EmitValueImpl(Value, Size, Loc);
+}
+
+void MCWasmStreamer::EmitValueToAlignment(unsigned ByteAlignment, int64_t Value,
+                                          unsigned ValueSize,
+                                          unsigned MaxBytesToEmit) {
+  MCObjectStreamer::EmitValueToAlignment(ByteAlignment, Value, ValueSize,
+                                         MaxBytesToEmit);
+}
+
+void MCWasmStreamer::EmitIdent(StringRef IdentString) {
+  // TODO(sbc): Add the ident section once we support mergable strings
+  // sections in the object format
+}
+
+void MCWasmStreamer::EmitInstToFragment(const MCInst &Inst,
+                                        const MCSubtargetInfo &STI) {
+  this->MCObjectStreamer::EmitInstToFragment(Inst, STI);
+}
+
+void MCWasmStreamer::EmitInstToData(const MCInst &Inst,
+                                    const MCSubtargetInfo &STI) {
+  MCAssembler &Assembler = getAssembler();
+  SmallVector<MCFixup, 4> Fixups;
+  SmallString<256> Code;
+  raw_svector_ostream VecOS(Code);
+  Assembler.getEmitter().encodeInstruction(Inst, VecOS, Fixups, STI);
+
+  // Append the encoded instruction to the current data fragment (or create a
+  // new such fragment if the current fragment is not a data fragment).
+  MCDataFragment *DF = getOrCreateDataFragment();
+
+  // Add the fixups and data.
+  for (unsigned I = 0, E = Fixups.size(); I != E; ++I) {
+    Fixups[I].setOffset(Fixups[I].getOffset() + DF->getContents().size());
+    DF->getFixups().push_back(Fixups[I]);
+  }
+  DF->setHasInstructions(STI);
+  DF->getContents().append(Code.begin(), Code.end());
+}
+
+void MCWasmStreamer::FinishImpl() {
+  EmitFrames(nullptr);
+
+  this->MCObjectStreamer::FinishImpl();
+}
+
+MCStreamer *llvm::createWasmStreamer(MCContext &Context,
+                                     std::unique_ptr<MCAsmBackend> &&MAB,
+                                     std::unique_ptr<MCObjectWriter> &&OW,
+                                     std::unique_ptr<MCCodeEmitter> &&CE,
+                                     bool RelaxAll) {
+  MCWasmStreamer *S =
+      new MCWasmStreamer(Context, std::move(MAB), std::move(OW), std::move(CE));
+  if (RelaxAll)
+    S->getAssembler().setRelaxAll(true);
+  return S;
+}
+
+void MCWasmStreamer::EmitThumbFunc(MCSymbol *Func) {
+  llvm_unreachable("Generic Wasm doesn't support this directive");
+}
+
+void MCWasmStreamer::EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) {
+  llvm_unreachable("Wasm doesn't support this directive");
+}
+
+void MCWasmStreamer::EmitZerofill(MCSection *Section, MCSymbol *Symbol,
+                                  uint64_t Size, unsigned ByteAlignment,
+                                  SMLoc Loc) {
+  llvm_unreachable("Wasm doesn't support this directive");
+}
+
+void MCWasmStreamer::EmitTBSSSymbol(MCSection *Section, MCSymbol *Symbol,
+                                    uint64_t Size, unsigned ByteAlignment) {
+  llvm_unreachable("Wasm doesn't support this directive");
+}