Commit 1933c9d4 authored by Andy Wingo's avatar Andy Wingo Committed by Sam Clegg
Browse files

[WebAssembly] Factor out WasmTableType in binary format 

This commit factors out a WasmTableType definition from WasmTable, as is
the case for WasmGlobal and other data types.  Also add support for
extracting the SymbolName for a table from the linking section's symbol
table.

Differential Revision: https://reviews.llvm.org/D91849
parent edd67564

lld/wasm/SyntheticSections.cpp

+1 −1
Original line number Diff line number Diff line
@@ -223,7 +223,7 @@ void TableSection::writeBody() { 
    limits = {0, tableSize, 0};

  else

    limits = {WASM_LIMITS_FLAG_HAS_MAX, tableSize, tableSize};

  writeTableType(os, WasmTable{0, WASM_TYPE_FUNCREF, limits});

  writeTableType(os, WasmTableType{WASM_TYPE_FUNCREF, limits});

}



void MemorySection::writeBody() {

lld/wasm/WriterUtils.cpp

+1 −1
Original line number Diff line number Diff line
@@ -195,7 +195,7 @@ void writeEvent(raw_ostream &os, const WasmEvent &event) { 
  writeEventType(os, event.Type);

}



void writeTableType(raw_ostream &os, const llvm::wasm::WasmTable &type) {

void writeTableType(raw_ostream &os, const WasmTableType &type) {

  writeU8(os, WASM_TYPE_FUNCREF, "table type");

  writeLimits(os, type.Limits);

}

lld/wasm/WriterUtils.h

+1 −1
Original line number Diff line number Diff line
@@ -54,7 +54,7 @@ void writeEventType(raw_ostream &os, const llvm::wasm::WasmEventType &type); 


void writeEvent(raw_ostream &os, const llvm::wasm::WasmEvent &event);



void writeTableType(raw_ostream &os, const llvm::wasm::WasmTable &type);

void writeTableType(raw_ostream &os, const llvm::wasm::WasmTableType &type);



void writeImport(raw_ostream &os, const llvm::wasm::WasmImport &import);

llvm/include/llvm/BinaryFormat/Wasm.h

+8 −3
Original line number Diff line number Diff line
@@ -67,12 +67,17 @@ struct WasmLimits { 
  uint64_t Maximum;

};



struct WasmTable {

  uint32_t Index;

struct WasmTableType {

  uint8_t ElemType;

  WasmLimits Limits;

};



struct WasmTable {

  uint32_t Index;

  WasmTableType Type;

  StringRef SymbolName; // from the "linking" section

};



struct WasmInitExpr {

  uint8_t Opcode;

  union {
@@ -115,7 +120,7 @@ struct WasmImport { 
  union {

    uint32_t SigIndex;

    WasmGlobalType Global;

    WasmTable Table;

    WasmTableType Table;

    WasmLimits Memory;

    WasmEventType Event;

  };

llvm/lib/MC/WasmObjectWriter.cpp

+7 −7
Original line number Diff line number Diff line
@@ -848,11 +848,11 @@ void WasmObjectWriter::writeTableSection(ArrayRef<wasm::WasmTable> Tables) { 


  encodeULEB128(Tables.size(), W->OS);

  for (const wasm::WasmTable &Table : Tables) {

    encodeULEB128(Table.ElemType, W->OS);

    encodeULEB128(Table.Limits.Flags, W->OS);

    encodeULEB128(Table.Limits.Initial, W->OS);

    if (Table.Limits.Flags & wasm::WASM_LIMITS_FLAG_HAS_MAX)

      encodeULEB128(Table.Limits.Maximum, W->OS);

    encodeULEB128(Table.Type.ElemType, W->OS);

    encodeULEB128(Table.Type.Limits.Flags, W->OS);

    encodeULEB128(Table.Type.Limits.Initial, W->OS);

    if (Table.Type.Limits.Flags & wasm::WASM_LIMITS_FLAG_HAS_MAX)

      encodeULEB128(Table.Type.Limits.Maximum, W->OS);

  }

  endSection(Section);

}
@@ -1527,10 +1527,10 @@ uint64_t WasmObjectWriter::writeOneObject(MCAssembler &Asm, 
      if (WS.isDefined()) {

        assert(WasmIndices.count(&WS) == 0);

        wasm::WasmTable Table;

        Table.ElemType = static_cast<uint8_t>(WS.getTableType());

        Table.Index = NumTableImports + Tables.size();

        Table.Type.ElemType = static_cast<uint8_t>(WS.getTableType());

        // FIXME: Work on custom limits is ongoing

        Table.Limits = {wasm::WASM_LIMITS_FLAG_NONE, 0, 0};

        Table.Type.Limits = {wasm::WASM_LIMITS_FLAG_NONE, 0, 0};



        WasmIndices[&WS] = Table.Index;

        Tables.push_back(Table);