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Diffstat (limited to 'contrib/llvm/lib/Target/WebAssembly/AsmParser/WebAssemblyAsmParser.cpp')
| -rw-r--r-- | contrib/llvm/lib/Target/WebAssembly/AsmParser/WebAssemblyAsmParser.cpp | 561 |
1 files changed, 561 insertions, 0 deletions
diff --git a/contrib/llvm/lib/Target/WebAssembly/AsmParser/WebAssemblyAsmParser.cpp b/contrib/llvm/lib/Target/WebAssembly/AsmParser/WebAssemblyAsmParser.cpp new file mode 100644 index 000000000000..2d92b93ca704 --- /dev/null +++ b/contrib/llvm/lib/Target/WebAssembly/AsmParser/WebAssemblyAsmParser.cpp @@ -0,0 +1,561 @@ +//==- WebAssemblyAsmParser.cpp - Assembler for WebAssembly -*- C++ -*-==// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +/// +/// \file +/// This file is part of the WebAssembly Assembler. +/// +/// It contains code to translate a parsed .s file into MCInsts. +/// +//===----------------------------------------------------------------------===// + +#include "MCTargetDesc/WebAssemblyMCTargetDesc.h" +#include "MCTargetDesc/WebAssemblyTargetStreamer.h" +#include "WebAssembly.h" +#include "llvm/MC/MCContext.h" +#include "llvm/MC/MCParser/MCTargetAsmParser.h" +#include "llvm/MC/MCParser/MCParsedAsmOperand.h" +#include "llvm/MC/MCInst.h" +#include "llvm/MC/MCInstrInfo.h" +#include "llvm/MC/MCSubtargetInfo.h" +#include "llvm/MC/MCSymbol.h" +#include "llvm/MC/MCStreamer.h" +#include "llvm/Support/Endian.h" +#include "llvm/Support/TargetRegistry.h" + +using namespace llvm; + +#define DEBUG_TYPE "wasm-asm-parser" + +namespace { + +// We store register types as SimpleValueType to retain SIMD layout +// information, but must also be able to supply them as the (unnamed) +// register enum from WebAssemblyRegisterInfo.td/.inc. +static unsigned MVTToWasmReg(MVT::SimpleValueType Type) { + switch(Type) { + case MVT::i32: return WebAssembly::I32_0; + case MVT::i64: return WebAssembly::I64_0; + case MVT::f32: return WebAssembly::F32_0; + case MVT::f64: return WebAssembly::F64_0; + case MVT::v16i8: return WebAssembly::V128_0; + case MVT::v8i16: return WebAssembly::V128_0; + case MVT::v4i32: return WebAssembly::V128_0; + case MVT::v4f32: return WebAssembly::V128_0; + default: return MVT::INVALID_SIMPLE_VALUE_TYPE; + } +} + +/// WebAssemblyOperand - Instances of this class represent the operands in a +/// parsed WASM machine instruction. +struct WebAssemblyOperand : public MCParsedAsmOperand { + enum KindTy { Token, Local, Stack, Integer, Float, Symbol } Kind; + + SMLoc StartLoc, EndLoc; + + struct TokOp { + StringRef Tok; + }; + + struct RegOp { + // This is a (virtual) local or stack register represented as 0.. + unsigned RegNo; + // In most targets, the register number also encodes the type, but for + // wasm we have to track that seperately since we have an unbounded + // number of registers. + // This has the unfortunate side effect that we supply a different value + // to the table-gen matcher at different times in the process (when it + // calls getReg() or addRegOperands(). + // TODO: While this works, it feels brittle. and would be nice to clean up. + MVT::SimpleValueType Type; + }; + + struct IntOp { + int64_t Val; + }; + + struct FltOp { + double Val; + }; + + struct SymOp { + const MCExpr *Exp; + }; + + union { + struct TokOp Tok; + struct RegOp Reg; + struct IntOp Int; + struct FltOp Flt; + struct SymOp Sym; + }; + + WebAssemblyOperand(KindTy K, SMLoc Start, SMLoc End, TokOp T) + : Kind(K), StartLoc(Start), EndLoc(End), Tok(T) {} + WebAssemblyOperand(KindTy K, SMLoc Start, SMLoc End, RegOp R) + : Kind(K), StartLoc(Start), EndLoc(End), Reg(R) {} + WebAssemblyOperand(KindTy K, SMLoc Start, SMLoc End, IntOp I) + : Kind(K), StartLoc(Start), EndLoc(End), Int(I) {} + WebAssemblyOperand(KindTy K, SMLoc Start, SMLoc End, FltOp F) + : Kind(K), StartLoc(Start), EndLoc(End), Flt(F) {} + WebAssemblyOperand(KindTy K, SMLoc Start, SMLoc End, SymOp S) + : Kind(K), StartLoc(Start), EndLoc(End), Sym(S) {} + + bool isToken() const override { return Kind == Token; } + bool isImm() const override { return Kind == Integer || + Kind == Float || + Kind == Symbol; } + bool isReg() const override { return Kind == Local || Kind == Stack; } + bool isMem() const override { return false; } + + unsigned getReg() const override { + assert(isReg()); + // This is called from the tablegen matcher (MatchInstructionImpl) + // where it expects to match the type of register, see RegOp above. + return MVTToWasmReg(Reg.Type); + } + + StringRef getToken() const { + assert(isToken()); + return Tok.Tok; + } + + SMLoc getStartLoc() const override { return StartLoc; } + SMLoc getEndLoc() const override { return EndLoc; } + + void addRegOperands(MCInst &Inst, unsigned N) const { + assert(N == 1 && "Invalid number of operands!"); + assert(isReg() && "Not a register operand!"); + // This is called from the tablegen matcher (MatchInstructionImpl) + // where it expects to output the actual register index, see RegOp above. + unsigned R = Reg.RegNo; + if (Kind == Stack) { + // A stack register is represented as a large negative number. + // See WebAssemblyRegNumbering::runOnMachineFunction and + // getWARegStackId for why this | is needed. + R |= INT32_MIN; + } + Inst.addOperand(MCOperand::createReg(R)); + } + + void addImmOperands(MCInst &Inst, unsigned N) const { + assert(N == 1 && "Invalid number of operands!"); + if (Kind == Integer) + Inst.addOperand(MCOperand::createImm(Int.Val)); + else if (Kind == Float) + Inst.addOperand(MCOperand::createFPImm(Flt.Val)); + else if (Kind == Symbol) + Inst.addOperand(MCOperand::createExpr(Sym.Exp)); + else + llvm_unreachable("Should be immediate or symbol!"); + } + + void print(raw_ostream &OS) const override { + switch (Kind) { + case Token: + OS << "Tok:" << Tok.Tok; + break; + case Local: + OS << "Loc:" << Reg.RegNo << ":" << static_cast<int>(Reg.Type); + break; + case Stack: + OS << "Stk:" << Reg.RegNo << ":" << static_cast<int>(Reg.Type); + break; + case Integer: + OS << "Int:" << Int.Val; + break; + case Float: + OS << "Flt:" << Flt.Val; + break; + case Symbol: + OS << "Sym:" << Sym.Exp; + break; + } + } +}; + +class WebAssemblyAsmParser final : public MCTargetAsmParser { + MCAsmParser &Parser; + MCAsmLexer &Lexer; + // These are for the current function being parsed: + // These are vectors since register assignments are so far non-sparse. + // Replace by map if necessary. + std::vector<MVT::SimpleValueType> LocalTypes; + std::vector<MVT::SimpleValueType> StackTypes; + MCSymbol *LastLabel; + +public: + WebAssemblyAsmParser(const MCSubtargetInfo &sti, MCAsmParser &Parser, + const MCInstrInfo &mii, const MCTargetOptions &Options) + : MCTargetAsmParser(Options, sti, mii), Parser(Parser), + Lexer(Parser.getLexer()), LastLabel(nullptr) { + } + +#define GET_ASSEMBLER_HEADER +#include "WebAssemblyGenAsmMatcher.inc" + + // TODO: This is required to be implemented, but appears unused. + bool ParseRegister(unsigned &/*RegNo*/, SMLoc &/*StartLoc*/, + SMLoc &/*EndLoc*/) override { + llvm_unreachable("ParseRegister is not implemented."); + } + + bool Error(const StringRef &msg, const AsmToken &tok) { + return Parser.Error(tok.getLoc(), msg + tok.getString()); + } + + bool IsNext(AsmToken::TokenKind Kind) { + auto ok = Lexer.is(Kind); + if (ok) Parser.Lex(); + return ok; + } + + bool Expect(AsmToken::TokenKind Kind, const char *KindName) { + if (!IsNext(Kind)) + return Error(std::string("Expected ") + KindName + ", instead got: ", + Lexer.getTok()); + return false; + } + + MVT::SimpleValueType ParseRegType(const StringRef &RegType) { + // Derive type from .param .local decls, or the instruction itself. + return StringSwitch<MVT::SimpleValueType>(RegType) + .Case("i32", MVT::i32) + .Case("i64", MVT::i64) + .Case("f32", MVT::f32) + .Case("f64", MVT::f64) + .Case("i8x16", MVT::v16i8) + .Case("i16x8", MVT::v8i16) + .Case("i32x4", MVT::v4i32) + .Case("f32x4", MVT::v4f32) + .Default(MVT::INVALID_SIMPLE_VALUE_TYPE); + } + + MVT::SimpleValueType &GetType( + std::vector<MVT::SimpleValueType> &Types, size_t i) { + Types.resize(std::max(i + 1, Types.size()), MVT::INVALID_SIMPLE_VALUE_TYPE); + return Types[i]; + } + + bool ParseReg(OperandVector &Operands, StringRef TypePrefix) { + if (Lexer.is(AsmToken::Integer)) { + auto &Local = Lexer.getTok(); + // This is a reference to a local, turn it into a virtual register. + auto LocalNo = static_cast<unsigned>(Local.getIntVal()); + Operands.push_back(make_unique<WebAssemblyOperand>( + WebAssemblyOperand::Local, Local.getLoc(), + Local.getEndLoc(), + WebAssemblyOperand::RegOp{LocalNo, + GetType(LocalTypes, LocalNo)})); + Parser.Lex(); + } else if (Lexer.is(AsmToken::Identifier)) { + auto &StackRegTok = Lexer.getTok(); + // These are push/pop/drop pseudo stack registers, which we turn + // into virtual registers also. The stackify pass will later turn them + // back into implicit stack references if possible. + auto StackReg = StackRegTok.getString(); + auto StackOp = StackReg.take_while([](char c) { return isalpha(c); }); + auto Reg = StackReg.drop_front(StackOp.size()); + unsigned long long ParsedRegNo = 0; + if (!Reg.empty() && getAsUnsignedInteger(Reg, 10, ParsedRegNo)) + return Error("Cannot parse stack register index: ", StackRegTok); + unsigned RegNo = static_cast<unsigned>(ParsedRegNo); + if (StackOp == "push") { + // This defines a result, record register type. + auto RegType = ParseRegType(TypePrefix); + GetType(StackTypes, RegNo) = RegType; + Operands.push_back(make_unique<WebAssemblyOperand>( + WebAssemblyOperand::Stack, + StackRegTok.getLoc(), + StackRegTok.getEndLoc(), + WebAssemblyOperand::RegOp{RegNo, RegType})); + } else if (StackOp == "pop") { + // This uses a previously defined stack value. + auto RegType = GetType(StackTypes, RegNo); + Operands.push_back(make_unique<WebAssemblyOperand>( + WebAssemblyOperand::Stack, + StackRegTok.getLoc(), + StackRegTok.getEndLoc(), + WebAssemblyOperand::RegOp{RegNo, RegType})); + } else if (StackOp == "drop") { + // This operand will be dropped, since it is part of an instruction + // whose result is void. + } else { + return Error("Unknown stack register prefix: ", StackRegTok); + } + Parser.Lex(); + } else { + return Error( + "Expected identifier/integer following $, instead got: ", + Lexer.getTok()); + } + IsNext(AsmToken::Equal); + return false; + } + + void ParseSingleInteger(bool IsNegative, OperandVector &Operands) { + auto &Int = Lexer.getTok(); + int64_t Val = Int.getIntVal(); + if (IsNegative) Val = -Val; + Operands.push_back(make_unique<WebAssemblyOperand>( + WebAssemblyOperand::Integer, Int.getLoc(), + Int.getEndLoc(), WebAssemblyOperand::IntOp{Val})); + Parser.Lex(); + } + + bool ParseOperandStartingWithInteger(bool IsNegative, + OperandVector &Operands, + StringRef InstType) { + ParseSingleInteger(IsNegative, Operands); + if (Lexer.is(AsmToken::LParen)) { + // Parse load/store operands of the form: offset($reg)align + auto &LParen = Lexer.getTok(); + Operands.push_back( + make_unique<WebAssemblyOperand>(WebAssemblyOperand::Token, + LParen.getLoc(), + LParen.getEndLoc(), + WebAssemblyOperand::TokOp{ + LParen.getString()})); + Parser.Lex(); + if (Expect(AsmToken::Dollar, "register")) return true; + if (ParseReg(Operands, InstType)) return true; + auto &RParen = Lexer.getTok(); + Operands.push_back( + make_unique<WebAssemblyOperand>(WebAssemblyOperand::Token, + RParen.getLoc(), + RParen.getEndLoc(), + WebAssemblyOperand::TokOp{ + RParen.getString()})); + if (Expect(AsmToken::RParen, ")")) return true; + if (Lexer.is(AsmToken::Integer)) { + ParseSingleInteger(false, Operands); + } else { + // Alignment not specified. + // FIXME: correctly derive a default from the instruction. + Operands.push_back(make_unique<WebAssemblyOperand>( + WebAssemblyOperand::Integer, RParen.getLoc(), + RParen.getEndLoc(), WebAssemblyOperand::IntOp{0})); + } + } + return false; + } + + bool ParseInstruction(ParseInstructionInfo &/*Info*/, StringRef Name, + SMLoc NameLoc, OperandVector &Operands) override { + Operands.push_back( + make_unique<WebAssemblyOperand>(WebAssemblyOperand::Token, NameLoc, + SMLoc::getFromPointer( + NameLoc.getPointer() + Name.size()), + WebAssemblyOperand::TokOp{ + StringRef(NameLoc.getPointer(), + Name.size())})); + auto NamePair = Name.split('.'); + // If no '.', there is no type prefix. + if (NamePair.second.empty()) std::swap(NamePair.first, NamePair.second); + while (Lexer.isNot(AsmToken::EndOfStatement)) { + auto &Tok = Lexer.getTok(); + switch (Tok.getKind()) { + case AsmToken::Dollar: { + Parser.Lex(); + if (ParseReg(Operands, NamePair.first)) return true; + break; + } + case AsmToken::Identifier: { + auto &Id = Lexer.getTok(); + const MCExpr *Val; + SMLoc End; + if (Parser.parsePrimaryExpr(Val, End)) + return Error("Cannot parse symbol: ", Lexer.getTok()); + Operands.push_back(make_unique<WebAssemblyOperand>( + WebAssemblyOperand::Symbol, Id.getLoc(), + Id.getEndLoc(), WebAssemblyOperand::SymOp{Val})); + break; + } + case AsmToken::Minus: + Parser.Lex(); + if (Lexer.isNot(AsmToken::Integer)) + return Error("Expected integer instead got: ", Lexer.getTok()); + if (ParseOperandStartingWithInteger(true, Operands, NamePair.first)) + return true; + break; + case AsmToken::Integer: + if (ParseOperandStartingWithInteger(false, Operands, NamePair.first)) + return true; + break; + case AsmToken::Real: { + double Val; + if (Tok.getString().getAsDouble(Val, false)) + return Error("Cannot parse real: ", Tok); + Operands.push_back(make_unique<WebAssemblyOperand>( + WebAssemblyOperand::Float, Tok.getLoc(), + Tok.getEndLoc(), WebAssemblyOperand::FltOp{Val})); + Parser.Lex(); + break; + } + default: + return Error("Unexpected token in operand: ", Tok); + } + if (Lexer.isNot(AsmToken::EndOfStatement)) { + if (Expect(AsmToken::Comma, ",")) return true; + } + } + Parser.Lex(); + // Call instructions are vararg, but the tablegen matcher doesn't seem to + // support that, so for now we strip these extra operands. + // This is problematic if these arguments are not simple $pop stack + // registers, since e.g. a local register would get lost, so we check for + // this. This can be the case when using -disable-wasm-explicit-locals + // which currently s2wasm requires. + // TODO: Instead, we can move this code to MatchAndEmitInstruction below and + // actually generate get_local instructions on the fly. + // Or even better, improve the matcher to support vararg? + auto IsIndirect = NamePair.second == "call_indirect"; + if (IsIndirect || NamePair.second == "call") { + // Figure out number of fixed operands from the instruction. + size_t CallOperands = 1; // The name token. + if (!IsIndirect) CallOperands++; // The function index. + if (!NamePair.first.empty()) CallOperands++; // The result register. + if (Operands.size() > CallOperands) { + // Ensure operands we drop are all $pop. + for (size_t I = CallOperands; I < Operands.size(); I++) { + auto Operand = + reinterpret_cast<WebAssemblyOperand *>(Operands[I].get()); + if (Operand->Kind != WebAssemblyOperand::Stack) + Parser.Error(NameLoc, + "Call instruction has non-stack arguments, if this code was " + "generated with -disable-wasm-explicit-locals please remove it"); + } + // Drop unneeded operands. + Operands.resize(CallOperands); + } + } + // Block instructions require a signature index, but these are missing in + // assembly, so we add a dummy one explicitly (since we have no control + // over signature tables here, we assume these will be regenerated when + // the wasm module is generated). + if (NamePair.second == "block" || NamePair.second == "loop") { + Operands.push_back(make_unique<WebAssemblyOperand>( + WebAssemblyOperand::Integer, NameLoc, + NameLoc, WebAssemblyOperand::IntOp{-1})); + } + // These don't specify the type, which has to derived from the local index. + if (NamePair.second == "get_local" || NamePair.second == "tee_local") { + if (Operands.size() >= 3 && Operands[1]->isReg() && + Operands[2]->isImm()) { + auto Op1 = reinterpret_cast<WebAssemblyOperand *>(Operands[1].get()); + auto Op2 = reinterpret_cast<WebAssemblyOperand *>(Operands[2].get()); + auto Type = GetType(LocalTypes, static_cast<size_t>(Op2->Int.Val)); + Op1->Reg.Type = Type; + GetType(StackTypes, Op1->Reg.RegNo) = Type; + } + } + return false; + } + + void onLabelParsed(MCSymbol *Symbol) override { + LastLabel = Symbol; + } + + bool ParseDirective(AsmToken DirectiveID) override { + assert(DirectiveID.getKind() == AsmToken::Identifier); + auto &Out = getStreamer(); + auto &TOut = reinterpret_cast<WebAssemblyTargetStreamer &>( + *Out.getTargetStreamer()); + // TODO: we're just parsing the subset of directives we're interested in, + // and ignoring ones we don't recognise. We should ideally verify + // all directives here. + if (DirectiveID.getString() == ".type") { + // This could be the start of a function, check if followed by + // "label,@function" + if (!(IsNext(AsmToken::Identifier) && + IsNext(AsmToken::Comma) && + IsNext(AsmToken::At) && + Lexer.is(AsmToken::Identifier))) + return Error("Expected label,@type declaration, got: ", Lexer.getTok()); + if (Lexer.getTok().getString() == "function") { + // Track locals from start of function. + LocalTypes.clear(); + StackTypes.clear(); + } + Parser.Lex(); + //Out.EmitSymbolAttribute(??, MCSA_ELF_TypeFunction); + } else if (DirectiveID.getString() == ".param" || + DirectiveID.getString() == ".local") { + // Track the number of locals, needed for correct virtual register + // assignment elsewhere. + // Also output a directive to the streamer. + std::vector<MVT> Params; + std::vector<MVT> Locals; + while (Lexer.is(AsmToken::Identifier)) { + auto RegType = ParseRegType(Lexer.getTok().getString()); + if (RegType == MVT::INVALID_SIMPLE_VALUE_TYPE) return true; + LocalTypes.push_back(RegType); + if (DirectiveID.getString() == ".param") { + Params.push_back(RegType); + } else { + Locals.push_back(RegType); + } + Parser.Lex(); + if (!IsNext(AsmToken::Comma)) break; + } + assert(LastLabel); + TOut.emitParam(LastLabel, Params); + TOut.emitLocal(Locals); + } else { + // For now, ignore anydirective we don't recognize: + while (Lexer.isNot(AsmToken::EndOfStatement)) Parser.Lex(); + } + return Expect(AsmToken::EndOfStatement, "EOL"); + } + + bool MatchAndEmitInstruction(SMLoc IDLoc, unsigned &/*Opcode*/, + OperandVector &Operands, + MCStreamer &Out, uint64_t &ErrorInfo, + bool MatchingInlineAsm) override { + MCInst Inst; + unsigned MatchResult = + MatchInstructionImpl(Operands, Inst, ErrorInfo, MatchingInlineAsm); + switch (MatchResult) { + case Match_Success: { + Out.EmitInstruction(Inst, getSTI()); + return false; + } + case Match_MissingFeature: + return Parser.Error(IDLoc, + "instruction requires a WASM feature not currently enabled"); + case Match_MnemonicFail: + return Parser.Error(IDLoc, "invalid instruction"); + case Match_NearMisses: + return Parser.Error(IDLoc, "ambiguous instruction"); + case Match_InvalidTiedOperand: + case Match_InvalidOperand: { + SMLoc ErrorLoc = IDLoc; + if (ErrorInfo != ~0ULL) { + if (ErrorInfo >= Operands.size()) + return Parser.Error(IDLoc, "too few operands for instruction"); + ErrorLoc = Operands[ErrorInfo]->getStartLoc(); + if (ErrorLoc == SMLoc()) + ErrorLoc = IDLoc; + } + return Parser.Error(ErrorLoc, "invalid operand for instruction"); + } + } + llvm_unreachable("Implement any new match types added!"); + } +}; +} // end anonymous namespace + +// Force static initialization. +extern "C" void LLVMInitializeWebAssemblyAsmParser() { + RegisterMCAsmParser<WebAssemblyAsmParser> X(getTheWebAssemblyTarget32()); + RegisterMCAsmParser<WebAssemblyAsmParser> Y(getTheWebAssemblyTarget64()); +} + +#define GET_REGISTER_MATCHER +#define GET_MATCHER_IMPLEMENTATION +#include "WebAssemblyGenAsmMatcher.inc" |