Sam Clegg 9504ab32b7 [WebAssembly] Second phase of implemented extended const proposal
This change continues to lay the ground work for supporting extended
const expressions in the linker.

The included test covers object file reading and writing and the YAML
representation.

Differential Revision: https://reviews.llvm.org/D121349
2022-03-14 08:55:47 -07:00

254 lines
8.3 KiB
C++

//===-- WasmDumper.cpp - Wasm-specific object file dumper -----------------===//
//
// 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 implements the Wasm-specific dumper for llvm-readobj.
//
//===----------------------------------------------------------------------===//
#include "ObjDumper.h"
#include "llvm-readobj.h"
#include "llvm/Object/Wasm.h"
#include "llvm/Support/ScopedPrinter.h"
using namespace llvm;
using namespace object;
namespace {
const EnumEntry<unsigned> WasmSymbolTypes[] = {
#define ENUM_ENTRY(X) \
{ #X, wasm::WASM_SYMBOL_TYPE_##X }
ENUM_ENTRY(FUNCTION), ENUM_ENTRY(DATA), ENUM_ENTRY(GLOBAL),
ENUM_ENTRY(SECTION), ENUM_ENTRY(TAG), ENUM_ENTRY(TABLE),
#undef ENUM_ENTRY
};
const EnumEntry<uint32_t> WasmSectionTypes[] = {
#define ENUM_ENTRY(X) \
{ #X, wasm::WASM_SEC_##X }
ENUM_ENTRY(CUSTOM), ENUM_ENTRY(TYPE), ENUM_ENTRY(IMPORT),
ENUM_ENTRY(FUNCTION), ENUM_ENTRY(TABLE), ENUM_ENTRY(MEMORY),
ENUM_ENTRY(GLOBAL), ENUM_ENTRY(TAG), ENUM_ENTRY(EXPORT),
ENUM_ENTRY(START), ENUM_ENTRY(ELEM), ENUM_ENTRY(CODE),
ENUM_ENTRY(DATA), ENUM_ENTRY(DATACOUNT),
#undef ENUM_ENTRY
};
const EnumEntry<unsigned> WasmSymbolFlags[] = {
#define ENUM_ENTRY(X) \
{ #X, wasm::WASM_SYMBOL_##X }
ENUM_ENTRY(BINDING_GLOBAL),
ENUM_ENTRY(BINDING_WEAK),
ENUM_ENTRY(BINDING_LOCAL),
ENUM_ENTRY(VISIBILITY_DEFAULT),
ENUM_ENTRY(VISIBILITY_HIDDEN),
ENUM_ENTRY(UNDEFINED),
ENUM_ENTRY(EXPORTED),
ENUM_ENTRY(EXPLICIT_NAME),
ENUM_ENTRY(NO_STRIP),
#undef ENUM_ENTRY
};
class WasmDumper : public ObjDumper {
public:
WasmDumper(const WasmObjectFile *Obj, ScopedPrinter &Writer)
: ObjDumper(Writer, Obj->getFileName()), Obj(Obj) {}
void printFileHeaders() override;
void printSectionHeaders() override;
void printRelocations() override;
void printUnwindInfo() override { llvm_unreachable("unimplemented"); }
void printStackMap() const override { llvm_unreachable("unimplemented"); }
protected:
void printSymbol(const SymbolRef &Sym);
void printRelocation(const SectionRef &Section, const RelocationRef &Reloc);
private:
void printSymbols() override;
void printDynamicSymbols() override { llvm_unreachable("unimplemented"); }
const WasmObjectFile *Obj;
};
void WasmDumper::printFileHeaders() {
W.printHex("Version", Obj->getHeader().Version);
}
void WasmDumper::printRelocation(const SectionRef &Section,
const RelocationRef &Reloc) {
SmallString<64> RelocTypeName;
uint64_t RelocType = Reloc.getType();
Reloc.getTypeName(RelocTypeName);
const wasm::WasmRelocation &WasmReloc = Obj->getWasmRelocation(Reloc);
StringRef SymName;
symbol_iterator SI = Reloc.getSymbol();
if (SI != Obj->symbol_end())
SymName = unwrapOrError(Obj->getFileName(), SI->getName());
bool HasAddend = wasm::relocTypeHasAddend(static_cast<uint32_t>(RelocType));
if (opts::ExpandRelocs) {
DictScope Group(W, "Relocation");
W.printNumber("Type", RelocTypeName, RelocType);
W.printHex("Offset", Reloc.getOffset());
if (!SymName.empty())
W.printString("Symbol", SymName);
else
W.printHex("Index", WasmReloc.Index);
if (HasAddend)
W.printNumber("Addend", WasmReloc.Addend);
} else {
raw_ostream &OS = W.startLine();
OS << W.hex(Reloc.getOffset()) << " " << RelocTypeName << " ";
if (!SymName.empty())
OS << SymName;
else
OS << WasmReloc.Index;
if (HasAddend)
OS << " " << WasmReloc.Addend;
OS << "\n";
}
}
void WasmDumper::printRelocations() {
ListScope D(W, "Relocations");
int SectionNumber = 0;
for (const SectionRef &Section : Obj->sections()) {
bool PrintedGroup = false;
StringRef Name = unwrapOrError(Obj->getFileName(), Section.getName());
++SectionNumber;
for (const RelocationRef &Reloc : Section.relocations()) {
if (!PrintedGroup) {
W.startLine() << "Section (" << SectionNumber << ") " << Name << " {\n";
W.indent();
PrintedGroup = true;
}
printRelocation(Section, Reloc);
}
if (PrintedGroup) {
W.unindent();
W.startLine() << "}\n";
}
}
}
void WasmDumper::printSymbols() {
ListScope Group(W, "Symbols");
for (const SymbolRef &Symbol : Obj->symbols())
printSymbol(Symbol);
}
void WasmDumper::printSectionHeaders() {
ListScope Group(W, "Sections");
for (const SectionRef &Section : Obj->sections()) {
const WasmSection &WasmSec = Obj->getWasmSection(Section);
DictScope SectionD(W, "Section");
W.printEnum("Type", WasmSec.Type, makeArrayRef(WasmSectionTypes));
W.printNumber("Size", static_cast<uint64_t>(WasmSec.Content.size()));
W.printNumber("Offset", WasmSec.Offset);
switch (WasmSec.Type) {
case wasm::WASM_SEC_CUSTOM:
W.printString("Name", WasmSec.Name);
if (WasmSec.Name == "linking") {
const wasm::WasmLinkingData &LinkingData = Obj->linkingData();
if (!LinkingData.InitFunctions.empty()) {
ListScope Group(W, "InitFunctions");
for (const wasm::WasmInitFunc &F : LinkingData.InitFunctions)
W.startLine() << F.Symbol << " (priority=" << F.Priority << ")\n";
}
}
break;
case wasm::WASM_SEC_DATA: {
ListScope Group(W, "Segments");
for (const WasmSegment &Segment : Obj->dataSegments()) {
const wasm::WasmDataSegment &Seg = Segment.Data;
DictScope Group(W, "Segment");
if (!Seg.Name.empty())
W.printString("Name", Seg.Name);
W.printNumber("Size", static_cast<uint64_t>(Seg.Content.size()));
if (Seg.Offset.Extended)
llvm_unreachable("extended const exprs not supported");
else if (Seg.Offset.Inst.Opcode == wasm::WASM_OPCODE_I32_CONST)
W.printNumber("Offset", Seg.Offset.Inst.Value.Int32);
else if (Seg.Offset.Inst.Opcode == wasm::WASM_OPCODE_I64_CONST)
W.printNumber("Offset", Seg.Offset.Inst.Value.Int64);
else if (Seg.Offset.Inst.Opcode == wasm::WASM_OPCODE_GLOBAL_GET) {
ListScope Group(W, "Offset");
W.printNumber("Global", Seg.Offset.Inst.Value.Global);
} else
llvm_unreachable("unknown init expr opcode");
}
break;
}
case wasm::WASM_SEC_MEMORY:
ListScope Group(W, "Memories");
for (const wasm::WasmLimits &Memory : Obj->memories()) {
DictScope Group(W, "Memory");
W.printNumber("MinPages", Memory.Minimum);
if (Memory.Flags & wasm::WASM_LIMITS_FLAG_HAS_MAX) {
W.printNumber("MaxPages", WasmSec.Offset);
}
}
break;
}
if (opts::SectionRelocations) {
ListScope D(W, "Relocations");
for (const RelocationRef &Reloc : Section.relocations())
printRelocation(Section, Reloc);
}
if (opts::SectionData) {
W.printBinaryBlock("SectionData", WasmSec.Content);
}
}
}
void WasmDumper::printSymbol(const SymbolRef &Sym) {
DictScope D(W, "Symbol");
WasmSymbol Symbol = Obj->getWasmSymbol(Sym.getRawDataRefImpl());
W.printString("Name", Symbol.Info.Name);
W.printEnum("Type", Symbol.Info.Kind, makeArrayRef(WasmSymbolTypes));
W.printFlags("Flags", Symbol.Info.Flags, makeArrayRef(WasmSymbolFlags));
if (Symbol.Info.Flags & wasm::WASM_SYMBOL_UNDEFINED) {
if (Symbol.Info.ImportName) {
W.printString("ImportName", *Symbol.Info.ImportName);
}
if (Symbol.Info.ImportModule) {
W.printString("ImportModule", *Symbol.Info.ImportModule);
}
}
if (Symbol.Info.Kind != wasm::WASM_SYMBOL_TYPE_DATA) {
W.printHex("ElementIndex", Symbol.Info.ElementIndex);
} else if (!(Symbol.Info.Flags & wasm::WASM_SYMBOL_UNDEFINED)) {
W.printHex("Offset", Symbol.Info.DataRef.Offset);
W.printHex("Segment", Symbol.Info.DataRef.Segment);
W.printHex("Size", Symbol.Info.DataRef.Size);
}
}
} // namespace
namespace llvm {
std::unique_ptr<ObjDumper> createWasmDumper(const object::WasmObjectFile &Obj,
ScopedPrinter &Writer) {
return std::make_unique<WasmDumper>(&Obj, Writer);
}
} // namespace llvm