1 //=- WebAssemblyInstPrinter.cpp - WebAssembly assembly instruction printing -=//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
11 /// \brief Print MCInst instructions to wasm format.
13 //===----------------------------------------------------------------------===//
15 #include "InstPrinter/WebAssemblyInstPrinter.h"
16 #include "MCTargetDesc/WebAssemblyMCTargetDesc.h"
17 #include "WebAssembly.h"
18 #include "WebAssemblyMachineFunctionInfo.h"
19 #include "llvm/ADT/SmallSet.h"
20 #include "llvm/ADT/StringExtras.h"
21 #include "llvm/MC/MCExpr.h"
22 #include "llvm/MC/MCInst.h"
23 #include "llvm/MC/MCInstrInfo.h"
24 #include "llvm/MC/MCSubtargetInfo.h"
25 #include "llvm/MC/MCSymbol.h"
26 #include "llvm/Support/ErrorHandling.h"
27 #include "llvm/Support/FormattedStream.h"
28 #include "llvm/Target/TargetRegisterInfo.h"
31 #define DEBUG_TYPE "asm-printer"
33 #include "WebAssemblyGenAsmWriter.inc"
35 WebAssemblyInstPrinter::WebAssemblyInstPrinter(const MCAsmInfo &MAI,
36 const MCInstrInfo &MII,
37 const MCRegisterInfo &MRI)
38 : MCInstPrinter(MAI, MII, MRI), ControlFlowCounter(0) {}
40 void WebAssemblyInstPrinter::printRegName(raw_ostream &OS,
41 unsigned RegNo) const {
42 assert(RegNo != WebAssemblyFunctionInfo::UnusedReg);
43 // Note that there's an implicit get_local/set_local here!
47 void WebAssemblyInstPrinter::printInst(const MCInst *MI, raw_ostream &OS,
49 const MCSubtargetInfo & /*STI*/) {
50 // Print the instruction (this uses the AsmStrings from the .td files).
51 printInstruction(MI, OS);
53 // Print any additional variadic operands.
54 const MCInstrDesc &Desc = MII.get(MI->getOpcode());
55 if (Desc.isVariadic())
56 for (auto i = Desc.getNumOperands(), e = MI->getNumOperands(); i < e; ++i) {
57 // FIXME: For CALL_INDIRECT_VOID, don't print a leading comma, because
58 // we have an extra flags operand which is not currently printed, for
59 // compatiblity reasons.
61 (MI->getOpcode() != WebAssembly::CALL_INDIRECT_VOID ||
62 i != Desc.getNumOperands()))
64 printOperand(MI, i, OS);
67 // Print any added annotation.
68 printAnnotation(OS, Annot);
71 // Observe any effects on the control flow stack, for use in annotating
72 // control flow label references.
73 switch (MI->getOpcode()) {
76 case WebAssembly::LOOP: {
77 printAnnotation(OS, "label" + utostr(ControlFlowCounter) + ':');
78 ControlFlowStack.push_back(std::make_pair(ControlFlowCounter++, true));
81 case WebAssembly::BLOCK:
82 ControlFlowStack.push_back(std::make_pair(ControlFlowCounter++, false));
84 case WebAssembly::END_LOOP:
85 ControlFlowStack.pop_back();
87 case WebAssembly::END_BLOCK:
89 OS, "label" + utostr(ControlFlowStack.pop_back_val().first) + ':');
93 // Annotate any control flow label references.
94 unsigned NumFixedOperands = Desc.NumOperands;
95 SmallSet<uint64_t, 8> Printed;
96 for (unsigned i = 0, e = MI->getNumOperands(); i < e; ++i) {
97 if (!(i < NumFixedOperands
98 ? (Desc.OpInfo[i].OperandType ==
99 WebAssembly::OPERAND_BASIC_BLOCK)
100 : (Desc.TSFlags & WebAssemblyII::VariableOpImmediateIsLabel)))
102 uint64_t Depth = MI->getOperand(i).getImm();
103 if (!Printed.insert(Depth).second)
105 const auto &Pair = ControlFlowStack.rbegin()[Depth];
106 printAnnotation(OS, utostr(Depth) + ": " + (Pair.second ? "up" : "down") +
107 " to label" + utostr(Pair.first));
112 static std::string toString(const APFloat &FP) {
113 // Print NaNs with custom payloads specially.
115 !FP.bitwiseIsEqual(APFloat::getQNaN(FP.getSemantics())) &&
117 APFloat::getQNaN(FP.getSemantics(), /*Negative=*/true))) {
118 APInt AI = FP.bitcastToAPInt();
120 std::string(AI.isNegative() ? "-" : "") + "nan:0x" +
121 utohexstr(AI.getZExtValue() &
122 (AI.getBitWidth() == 32 ? INT64_C(0x007fffff) :
123 INT64_C(0x000fffffffffffff)),
127 // Use C99's hexadecimal floating-point representation.
128 static const size_t BufBytes = 128;
130 auto Written = FP.convertToHexString(
131 buf, /*hexDigits=*/0, /*upperCase=*/false, APFloat::rmNearestTiesToEven);
133 assert(Written != 0);
134 assert(Written < BufBytes);
138 void WebAssemblyInstPrinter::printOperand(const MCInst *MI, unsigned OpNo,
140 const MCOperand &Op = MI->getOperand(OpNo);
142 assert((OpNo < MII.get(MI->getOpcode()).getNumOperands() ||
143 MII.get(MI->getOpcode()).TSFlags == 0) &&
144 "WebAssembly variable_ops register ops don't use TSFlags");
145 unsigned WAReg = Op.getReg();
147 printRegName(O, WAReg);
148 else if (OpNo >= MII.get(MI->getOpcode()).getNumDefs())
149 O << "$pop" << WebAssemblyFunctionInfo::getWARegStackId(WAReg);
150 else if (WAReg != WebAssemblyFunctionInfo::UnusedReg)
151 O << "$push" << WebAssemblyFunctionInfo::getWARegStackId(WAReg);
154 // Add a '=' suffix if this is a def.
155 if (OpNo < MII.get(MI->getOpcode()).getNumDefs())
157 } else if (Op.isImm()) {
158 const MCInstrDesc &Desc = MII.get(MI->getOpcode());
159 assert((OpNo < Desc.getNumOperands() ||
160 (Desc.TSFlags & WebAssemblyII::VariableOpIsImmediate)) &&
161 "WebAssemblyII::VariableOpIsImmediate should be set for "
162 "variable_ops immediate ops");
164 // TODO: (MII.get(MI->getOpcode()).TSFlags &
165 // WebAssemblyII::VariableOpImmediateIsLabel)
166 // can tell us whether this is an immediate referencing a label in the
167 // control flow stack, and it may be nice to pretty-print.
169 } else if (Op.isFPImm()) {
170 const MCInstrDesc &Desc = MII.get(MI->getOpcode());
171 assert(OpNo < Desc.getNumOperands() &&
172 "Unexpected floating-point immediate as a non-fixed operand");
173 assert(Desc.TSFlags == 0 &&
174 "WebAssembly variable_ops floating point ops don't use TSFlags");
175 const MCOperandInfo &Info = Desc.OpInfo[OpNo];
176 if (Info.OperandType == WebAssembly::OPERAND_F32IMM) {
177 // TODO: MC converts all floating point immediate operands to double.
178 // This is fine for numeric values, but may cause NaNs to change bits.
179 O << toString(APFloat(float(Op.getFPImm())));
181 assert(Info.OperandType == WebAssembly::OPERAND_F64IMM);
182 O << toString(APFloat(Op.getFPImm()));
185 assert((OpNo < MII.get(MI->getOpcode()).getNumOperands() ||
186 (MII.get(MI->getOpcode()).TSFlags &
187 WebAssemblyII::VariableOpIsImmediate)) &&
188 "WebAssemblyII::VariableOpIsImmediate should be set for "
189 "variable_ops expr ops");
190 assert(Op.isExpr() && "unknown operand kind in printOperand");
191 Op.getExpr()->print(O, &MAI);
196 WebAssemblyInstPrinter::printWebAssemblyP2AlignOperand(const MCInst *MI,
199 int64_t Imm = MI->getOperand(OpNo).getImm();
200 if (Imm == WebAssembly::GetDefaultP2Align(MI->getOpcode()))
202 O << ":p2align=" << Imm;
206 WebAssemblyInstPrinter::printWebAssemblySignatureOperand(const MCInst *MI,
209 int64_t Imm = MI->getOperand(OpNo).getImm();
210 switch (WebAssembly::ExprType(Imm)) {
211 case WebAssembly::ExprType::Void: break;
212 case WebAssembly::ExprType::I32: O << "i32"; break;
213 case WebAssembly::ExprType::I64: O << "i64"; break;
214 case WebAssembly::ExprType::F32: O << "f32"; break;
215 case WebAssembly::ExprType::F64: O << "f64"; break;
216 case WebAssembly::ExprType::I8x16: O << "i8x16"; break;
217 case WebAssembly::ExprType::I16x8: O << "i16x8"; break;
218 case WebAssembly::ExprType::I32x4: O << "i32x4"; break;
219 case WebAssembly::ExprType::F32x4: O << "f32x4"; break;
220 case WebAssembly::ExprType::B8x16: O << "b8x16"; break;
221 case WebAssembly::ExprType::B16x8: O << "b16x8"; break;
222 case WebAssembly::ExprType::B32x4: O << "b32x4"; break;
226 const char *llvm::WebAssembly::TypeToString(MVT Ty) {
227 switch (Ty.SimpleTy) {
242 llvm_unreachable("unsupported type");
246 const char *llvm::WebAssembly::TypeToString(wasm::ValType Type) {
248 case wasm::ValType::I32:
250 case wasm::ValType::I64:
252 case wasm::ValType::F32:
254 case wasm::ValType::F64:
257 llvm_unreachable("unsupported type");