| //=- WebAssemblyInstPrinter.cpp - WebAssembly assembly instruction printing -=// |
| // |
| // 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 |
| // |
| //===----------------------------------------------------------------------===// |
| /// |
| /// \file |
| /// Print MCInst instructions to wasm format. |
| /// |
| //===----------------------------------------------------------------------===// |
| |
| #include "MCTargetDesc/WebAssemblyInstPrinter.h" |
| #include "MCTargetDesc/WebAssemblyMCTargetDesc.h" |
| #include "WebAssembly.h" |
| #include "WebAssemblyMachineFunctionInfo.h" |
| #include "WebAssemblyUtilities.h" |
| #include "llvm/ADT/SmallSet.h" |
| #include "llvm/ADT/StringExtras.h" |
| #include "llvm/CodeGen/TargetRegisterInfo.h" |
| #include "llvm/MC/MCExpr.h" |
| #include "llvm/MC/MCInst.h" |
| #include "llvm/MC/MCInstrInfo.h" |
| #include "llvm/MC/MCSubtargetInfo.h" |
| #include "llvm/MC/MCSymbol.h" |
| #include "llvm/Support/ErrorHandling.h" |
| #include "llvm/Support/FormattedStream.h" |
| using namespace llvm; |
| |
| #define DEBUG_TYPE "asm-printer" |
| |
| #include "WebAssemblyGenAsmWriter.inc" |
| |
| WebAssemblyInstPrinter::WebAssemblyInstPrinter(const MCAsmInfo &MAI, |
| const MCInstrInfo &MII, |
| const MCRegisterInfo &MRI) |
| : MCInstPrinter(MAI, MII, MRI) {} |
| |
| void WebAssemblyInstPrinter::printRegName(raw_ostream &OS, |
| unsigned RegNo) const { |
| assert(RegNo != WebAssemblyFunctionInfo::UnusedReg); |
| // Note that there's an implicit local.get/local.set here! |
| OS << "$" << RegNo; |
| } |
| |
| void WebAssemblyInstPrinter::printInst(const MCInst *MI, uint64_t Address, |
| StringRef Annot, |
| const MCSubtargetInfo &STI, |
| raw_ostream &OS) { |
| // Print the instruction (this uses the AsmStrings from the .td files). |
| printInstruction(MI, Address, OS); |
| |
| // Print any additional variadic operands. |
| const MCInstrDesc &Desc = MII.get(MI->getOpcode()); |
| if (Desc.isVariadic()) { |
| if (Desc.getNumOperands() == 0 && MI->getNumOperands() > 0) |
| OS << "\t"; |
| for (auto I = Desc.getNumOperands(), E = MI->getNumOperands(); I < E; ++I) { |
| // FIXME: For CALL_INDIRECT_VOID, don't print a leading comma, because |
| // we have an extra flags operand which is not currently printed, for |
| // compatiblity reasons. |
| if (I != 0 && ((MI->getOpcode() != WebAssembly::CALL_INDIRECT_VOID && |
| MI->getOpcode() != WebAssembly::CALL_INDIRECT_VOID_S) || |
| I != Desc.getNumOperands())) |
| OS << ", "; |
| printOperand(MI, I, OS); |
| } |
| } |
| |
| // Print any added annotation. |
| printAnnotation(OS, Annot); |
| |
| if (CommentStream) { |
| // Observe any effects on the control flow stack, for use in annotating |
| // control flow label references. |
| unsigned Opc = MI->getOpcode(); |
| switch (Opc) { |
| default: |
| break; |
| |
| case WebAssembly::LOOP: |
| case WebAssembly::LOOP_S: |
| printAnnotation(OS, "label" + utostr(ControlFlowCounter) + ':'); |
| ControlFlowStack.push_back(std::make_pair(ControlFlowCounter++, true)); |
| break; |
| |
| case WebAssembly::BLOCK: |
| case WebAssembly::BLOCK_S: |
| ControlFlowStack.push_back(std::make_pair(ControlFlowCounter++, false)); |
| break; |
| |
| case WebAssembly::TRY: |
| case WebAssembly::TRY_S: |
| ControlFlowStack.push_back(std::make_pair(ControlFlowCounter++, false)); |
| EHPadStack.push_back(EHPadStackCounter++); |
| LastSeenEHInst = TRY; |
| break; |
| |
| case WebAssembly::END_LOOP: |
| case WebAssembly::END_LOOP_S: |
| if (ControlFlowStack.empty()) { |
| printAnnotation(OS, "End marker mismatch!"); |
| } else { |
| ControlFlowStack.pop_back(); |
| } |
| break; |
| |
| case WebAssembly::END_BLOCK: |
| case WebAssembly::END_BLOCK_S: |
| if (ControlFlowStack.empty()) { |
| printAnnotation(OS, "End marker mismatch!"); |
| } else { |
| printAnnotation( |
| OS, "label" + utostr(ControlFlowStack.pop_back_val().first) + ':'); |
| } |
| break; |
| |
| case WebAssembly::END_TRY: |
| case WebAssembly::END_TRY_S: |
| if (ControlFlowStack.empty()) { |
| printAnnotation(OS, "End marker mismatch!"); |
| } else { |
| printAnnotation( |
| OS, "label" + utostr(ControlFlowStack.pop_back_val().first) + ':'); |
| LastSeenEHInst = END_TRY; |
| } |
| break; |
| |
| case WebAssembly::CATCH: |
| case WebAssembly::CATCH_S: |
| if (EHPadStack.empty()) { |
| printAnnotation(OS, "try-catch mismatch!"); |
| } else { |
| printAnnotation(OS, "catch" + utostr(EHPadStack.pop_back_val()) + ':'); |
| } |
| break; |
| } |
| |
| // Annotate any control flow label references. |
| |
| // rethrow instruction does not take any depth argument and rethrows to the |
| // nearest enclosing catch scope, if any. If there's no enclosing catch |
| // scope, it throws up to the caller. |
| if (Opc == WebAssembly::RETHROW || Opc == WebAssembly::RETHROW_S) { |
| if (EHPadStack.empty()) { |
| printAnnotation(OS, "to caller"); |
| } else { |
| printAnnotation(OS, "down to catch" + utostr(EHPadStack.back())); |
| } |
| |
| } else { |
| unsigned NumFixedOperands = Desc.NumOperands; |
| SmallSet<uint64_t, 8> Printed; |
| for (unsigned I = 0, E = MI->getNumOperands(); I < E; ++I) { |
| // See if this operand denotes a basic block target. |
| if (I < NumFixedOperands) { |
| // A non-variable_ops operand, check its type. |
| if (Desc.OpInfo[I].OperandType != WebAssembly::OPERAND_BASIC_BLOCK) |
| continue; |
| } else { |
| // A variable_ops operand, which currently can be immediates (used in |
| // br_table) which are basic block targets, or for call instructions |
| // when using -wasm-keep-registers (in which case they are registers, |
| // and should not be processed). |
| if (!MI->getOperand(I).isImm()) |
| continue; |
| } |
| uint64_t Depth = MI->getOperand(I).getImm(); |
| if (!Printed.insert(Depth).second) |
| continue; |
| if (Depth >= ControlFlowStack.size()) { |
| printAnnotation(OS, "Invalid depth argument!"); |
| } else { |
| const auto &Pair = ControlFlowStack.rbegin()[Depth]; |
| printAnnotation(OS, utostr(Depth) + ": " + |
| (Pair.second ? "up" : "down") + " to label" + |
| utostr(Pair.first)); |
| } |
| } |
| } |
| } |
| } |
| |
| static std::string toString(const APFloat &FP) { |
| // Print NaNs with custom payloads specially. |
| if (FP.isNaN() && !FP.bitwiseIsEqual(APFloat::getQNaN(FP.getSemantics())) && |
| !FP.bitwiseIsEqual( |
| APFloat::getQNaN(FP.getSemantics(), /*Negative=*/true))) { |
| APInt AI = FP.bitcastToAPInt(); |
| return std::string(AI.isNegative() ? "-" : "") + "nan:0x" + |
| utohexstr(AI.getZExtValue() & |
| (AI.getBitWidth() == 32 ? INT64_C(0x007fffff) |
| : INT64_C(0x000fffffffffffff)), |
| /*LowerCase=*/true); |
| } |
| |
| // Use C99's hexadecimal floating-point representation. |
| static const size_t BufBytes = 128; |
| char Buf[BufBytes]; |
| auto Written = FP.convertToHexString( |
| Buf, /*HexDigits=*/0, /*UpperCase=*/false, APFloat::rmNearestTiesToEven); |
| (void)Written; |
| assert(Written != 0); |
| assert(Written < BufBytes); |
| return Buf; |
| } |
| |
| void WebAssemblyInstPrinter::printOperand(const MCInst *MI, unsigned OpNo, |
| raw_ostream &O) { |
| const MCOperand &Op = MI->getOperand(OpNo); |
| if (Op.isReg()) { |
| unsigned WAReg = Op.getReg(); |
| if (int(WAReg) >= 0) |
| printRegName(O, WAReg); |
| else if (OpNo >= MII.get(MI->getOpcode()).getNumDefs()) |
| O << "$pop" << WebAssemblyFunctionInfo::getWARegStackId(WAReg); |
| else if (WAReg != WebAssemblyFunctionInfo::UnusedReg) |
| O << "$push" << WebAssemblyFunctionInfo::getWARegStackId(WAReg); |
| else |
| O << "$drop"; |
| // Add a '=' suffix if this is a def. |
| if (OpNo < MII.get(MI->getOpcode()).getNumDefs()) |
| O << '='; |
| } else if (Op.isImm()) { |
| O << Op.getImm(); |
| } else if (Op.isFPImm()) { |
| const MCInstrDesc &Desc = MII.get(MI->getOpcode()); |
| const MCOperandInfo &Info = Desc.OpInfo[OpNo]; |
| if (Info.OperandType == WebAssembly::OPERAND_F32IMM) { |
| // TODO: MC converts all floating point immediate operands to double. |
| // This is fine for numeric values, but may cause NaNs to change bits. |
| O << ::toString(APFloat(float(Op.getFPImm()))); |
| } else { |
| assert(Info.OperandType == WebAssembly::OPERAND_F64IMM); |
| O << ::toString(APFloat(Op.getFPImm())); |
| } |
| } else { |
| assert(Op.isExpr() && "unknown operand kind in printOperand"); |
| // call_indirect instructions have a TYPEINDEX operand that we print |
| // as a signature here, such that the assembler can recover this |
| // information. |
| auto SRE = static_cast<const MCSymbolRefExpr *>(Op.getExpr()); |
| if (SRE->getKind() == MCSymbolRefExpr::VK_WASM_TYPEINDEX) { |
| auto &Sym = static_cast<const MCSymbolWasm &>(SRE->getSymbol()); |
| O << WebAssembly::signatureToString(Sym.getSignature()); |
| } else { |
| Op.getExpr()->print(O, &MAI); |
| } |
| } |
| } |
| |
| void WebAssemblyInstPrinter::printBrList(const MCInst *MI, unsigned OpNo, |
| raw_ostream &O) { |
| O << "{"; |
| for (unsigned I = OpNo, E = MI->getNumOperands(); I != E; ++I) { |
| if (I != OpNo) |
| O << ", "; |
| O << MI->getOperand(I).getImm(); |
| } |
| O << "}"; |
| } |
| |
| void WebAssemblyInstPrinter::printWebAssemblyP2AlignOperand(const MCInst *MI, |
| unsigned OpNo, |
| raw_ostream &O) { |
| int64_t Imm = MI->getOperand(OpNo).getImm(); |
| if (Imm == WebAssembly::GetDefaultP2Align(MI->getOpcode())) |
| return; |
| O << ":p2align=" << Imm; |
| } |
| |
| void WebAssemblyInstPrinter::printWebAssemblySignatureOperand(const MCInst *MI, |
| unsigned OpNo, |
| raw_ostream &O) { |
| const MCOperand &Op = MI->getOperand(OpNo); |
| if (Op.isImm()) { |
| auto Imm = static_cast<unsigned>(Op.getImm()); |
| if (Imm != wasm::WASM_TYPE_NORESULT) |
| O << WebAssembly::anyTypeToString(Imm); |
| } else { |
| auto Expr = cast<MCSymbolRefExpr>(Op.getExpr()); |
| auto *Sym = cast<MCSymbolWasm>(&Expr->getSymbol()); |
| if (Sym->getSignature()) { |
| O << WebAssembly::signatureToString(Sym->getSignature()); |
| } else { |
| // Disassembler does not currently produce a signature |
| O << "unknown_type"; |
| } |
| } |
| } |
| |
| // We have various enums representing a subset of these types, use this |
| // function to convert any of them to text. |
| const char *WebAssembly::anyTypeToString(unsigned Ty) { |
| switch (Ty) { |
| case wasm::WASM_TYPE_I32: |
| return "i32"; |
| case wasm::WASM_TYPE_I64: |
| return "i64"; |
| case wasm::WASM_TYPE_F32: |
| return "f32"; |
| case wasm::WASM_TYPE_F64: |
| return "f64"; |
| case wasm::WASM_TYPE_V128: |
| return "v128"; |
| case wasm::WASM_TYPE_FUNCREF: |
| return "funcref"; |
| case wasm::WASM_TYPE_FUNC: |
| return "func"; |
| case wasm::WASM_TYPE_EXNREF: |
| return "exnref"; |
| case wasm::WASM_TYPE_NORESULT: |
| return "void"; |
| default: |
| return "invalid_type"; |
| } |
| } |
| |
| const char *WebAssembly::typeToString(wasm::ValType Ty) { |
| return anyTypeToString(static_cast<unsigned>(Ty)); |
| } |
| |
| std::string WebAssembly::typeListToString(ArrayRef<wasm::ValType> List) { |
| std::string S; |
| for (auto &Ty : List) { |
| if (&Ty != &List[0]) S += ", "; |
| S += WebAssembly::typeToString(Ty); |
| } |
| return S; |
| } |
| |
| std::string WebAssembly::signatureToString(const wasm::WasmSignature *Sig) { |
| std::string S("("); |
| S += typeListToString(Sig->Params); |
| S += ") -> ("; |
| S += typeListToString(Sig->Returns); |
| S += ")"; |
| return S; |
| } |
