+// Helpers.
+//===----------------------------------------------------------------------===//
+
+// Operand type (if any), followed by the lower-case version of the opcode's
+// name matching the names WebAssembly opcodes are expected to have. The
+// tablegen names are uppercase and suffixed with their type (after an
+// underscore). Conversions are additionally prefixed with their input type
+// (before a double underscore).
+static std::string OpcodeName(const WebAssemblyInstrInfo *TII,
+ const MachineInstr *MI) {
+ std::string N(StringRef(TII->getName(MI->getOpcode())).lower());
+ std::string::size_type Len = N.length();
+ std::string::size_type Under = N.rfind('_');
+ bool HasType = std::string::npos != Under;
+ std::string::size_type NameEnd = HasType ? Under : Len;
+ std::string Name(&N[0], &N[NameEnd]);
+ if (!HasType)
+ return Name;
+ for (const char *typelessOpcode : { "return", "call", "br_if" })
+ if (Name == typelessOpcode)
+ return Name;
+ std::string Type(&N[NameEnd + 1], &N[Len]);
+ std::string::size_type DoubleUnder = Name.find("__");
+ bool IsConv = std::string::npos != DoubleUnder;
+ if (!IsConv)
+ return Type + '.' + Name;
+ std::string InType(&Name[0], &Name[DoubleUnder]);
+ return Type + '.' + std::string(&Name[DoubleUnder + 2], &Name[NameEnd]) +
+ '/' + InType;
+}
+
+static std::string toSymbol(StringRef S) { return ("$" + S).str(); }
+
+std::string WebAssemblyAsmPrinter::getRegTypeName(unsigned RegNo) const {
+ const TargetRegisterClass *TRC = MRI->getRegClass(RegNo);
+ for (MVT T : {MVT::i32, MVT::i64, MVT::f32, MVT::f64})
+ if (TRC->hasType(T))
+ return EVT(T).getEVTString();
+ DEBUG(errs() << "Unknown type for register number: " << RegNo);
+ llvm_unreachable("Unknown register type");
+ return "?";
+}
+
+std::string WebAssemblyAsmPrinter::toString(const APFloat &FP) {
+ static const size_t BufBytes = 128;
+ char buf[BufBytes];
+ if (FP.isNaN())
+ assert((FP.bitwiseIsEqual(APFloat::getQNaN(FP.getSemantics())) ||
+ FP.bitwiseIsEqual(
+ APFloat::getQNaN(FP.getSemantics(), /*Negative=*/true))) &&
+ "convertToHexString handles neither SNaN nor NaN payloads");
+ // Use C99's hexadecimal floating-point representation.
+ auto Written = FP.convertToHexString(
+ buf, /*hexDigits=*/0, /*upperCase=*/false, APFloat::rmNearestTiesToEven);
+ (void)Written;
+ assert(Written != 0);
+ assert(Written < BufBytes);
+ return buf;
+}
+
+std::string WebAssemblyAsmPrinter::regToString(const MachineOperand &MO) {
+ unsigned RegNo = MO.getReg();
+ if (TargetRegisterInfo::isPhysicalRegister(RegNo))
+ return WebAssemblyInstPrinter::getRegisterName(RegNo);
+
+ // WebAssembly arguments and local variables are in the same index space, and
+ // there are no explicit varargs, so we just add the number of arguments to
+ // the virtual register number to get the local variable number.
+ return utostr(TargetRegisterInfo::virtReg2Index(RegNo) + NumArgs);
+}
+
+std::string WebAssemblyAsmPrinter::argToString(const MachineOperand &MO) {
+ unsigned ArgNo = MO.getImm();
+ // Same as above, but we don't need to add NumArgs here.
+ return utostr(ArgNo);
+}
+
+const char *WebAssemblyAsmPrinter::toString(Type *Ty) const {
+ switch (Ty->getTypeID()) {
+ default:
+ break;
+ // Treat all pointers as the underlying integer into linear memory.
+ case Type::PointerTyID:
+ switch (getPointerSize()) {
+ case 4:
+ return "i32";
+ case 8:
+ return "i64";
+ default:
+ llvm_unreachable("unsupported pointer size");
+ }
+ break;
+ case Type::FloatTyID:
+ return "f32";
+ case Type::DoubleTyID:
+ return "f64";
+ case Type::IntegerTyID:
+ switch (Ty->getIntegerBitWidth()) {
+ case 8:
+ return "i8";
+ case 16:
+ return "i16";
+ case 32:
+ return "i32";
+ case 64:
+ return "i64";
+ default:
+ break;
+ }
+ }
+ DEBUG(dbgs() << "Invalid type "; Ty->print(dbgs()); dbgs() << '\n');
+ llvm_unreachable("invalid type");
+ return "<invalid>";
+}
+
+//===----------------------------------------------------------------------===//
+// WebAssemblyAsmPrinter Implementation.
+//===----------------------------------------------------------------------===//
+
+void WebAssemblyAsmPrinter::EmitConstantPool() {
+ assert(MF->getConstantPool()->getConstants().empty() &&
+ "WebAssembly disables constant pools");
+}
+
+void WebAssemblyAsmPrinter::EmitJumpTableInfo() {
+ // Nothing to do; jump tables are incorporated into the instruction stream.
+}
+
+void WebAssemblyAsmPrinter::EmitFunctionBodyStart() {
+ const Function *F = MF->getFunction();
+ Type *Rt = F->getReturnType();
+ SmallString<128> Str;
+ raw_svector_ostream OS(Str);
+ bool First = true;
+
+ if (!Rt->isVoidTy() || !F->arg_empty()) {
+ for (const Argument &A : F->args()) {
+ OS << (First ? "" : "\n") << "\t.param " << toString(A.getType());
+ First = false;
+ }
+ if (!Rt->isVoidTy()) {
+ OS << (First ? "" : "\n") << "\t.result " << toString(Rt);
+ First = false;
+ }
+ }
+
+ bool FirstVReg = true;
+ for (unsigned Idx = 0, IdxE = MRI->getNumVirtRegs(); Idx != IdxE; ++Idx) {
+ unsigned VReg = TargetRegisterInfo::index2VirtReg(Idx);
+ // FIXME: Don't skip dead virtual registers for now: that would require
+ // remapping all locals' numbers.
+ //if (!MRI->use_empty(VReg)) {
+ if (FirstVReg) {
+ OS << (First ? "" : "\n") << "\t.local ";
+ First = false;
+ }
+ OS << (FirstVReg ? "" : ", ") << getRegTypeName(VReg);
+ FirstVReg = false;
+ //}
+ }
+
+ if (!First)
+ OutStreamer->EmitRawText(OS.str());
+ AsmPrinter::EmitFunctionBodyStart();
+}