Revert r252858: "[WebAssembly] Switch to MC for instruction printing."

It broke the CMake build:

"Cannot find source file: WebAssemblyRegNumbering.cpp"

llvm-svn: 252897

1 files changed, 145 insertions, 36 deletions

diff --git a/llvm/lib/Target/WebAssembly/WebAssemblyAsmPrinter.cpp b/llvm/lib/Target/WebAssembly/WebAssemblyAsmPrinter.cpp
index 641d6ea2b86..27095ec51df 100644
--- a/llvm/lib/Target/WebAssembly/WebAssemblyAsmPrinter.cpp
+++ b/llvm/lib/Target/WebAssembly/WebAssemblyAsmPrinter.cpp
@@ -15,12 +15,12 @@
 //===----------------------------------------------------------------------===//
 
 #include "WebAssembly.h"
-#include "InstPrinter/WebAssemblyInstPrinter.h"
-#include "MCTargetDesc/WebAssemblyMCTargetDesc.h"
-#include "WebAssemblyMCInstLower.h"
 #include "WebAssemblyMachineFunctionInfo.h"
 #include "WebAssemblyRegisterInfo.h"
 #include "WebAssemblySubtarget.h"
+#include "InstPrinter/WebAssemblyInstPrinter.h"
+#include "MCTargetDesc/WebAssemblyMCTargetDesc.h"
+
 #include "llvm/ADT/SmallString.h"
 #include "llvm/ADT/StringExtras.h"
 #include "llvm/CodeGen/Analysis.h"
@@ -28,7 +28,7 @@
 #include "llvm/CodeGen/MachineConstantPool.h"
 #include "llvm/CodeGen/MachineInstr.h"
 #include "llvm/IR/DataLayout.h"
-#include "llvm/MC/MCContext.h"
+#include "llvm/IR/DebugInfo.h"
 #include "llvm/MC/MCStreamer.h"
 #include "llvm/MC/MCSymbol.h"
 #include "llvm/Support/Debug.h"
@@ -42,12 +42,13 @@ using namespace llvm;
 namespace {
 
 class WebAssemblyAsmPrinter final : public AsmPrinter {
+  const WebAssemblyInstrInfo *TII;
   const MachineRegisterInfo *MRI;
-  const WebAssemblyFunctionInfo *MFI;
+  unsigned NumArgs;
 
 public:
   WebAssemblyAsmPrinter(TargetMachine &TM, std::unique_ptr<MCStreamer> Streamer)
-      : AsmPrinter(TM, std::move(Streamer)), MRI(nullptr), MFI(nullptr) {}
+      : AsmPrinter(TM, std::move(Streamer)), TII(nullptr), MRI(nullptr) {}
 
 private:
   const char *getPassName() const override {
@@ -63,8 +64,10 @@ private:
   }
 
   bool runOnMachineFunction(MachineFunction &MF) override {
+    const auto &Subtarget = MF.getSubtarget<WebAssemblySubtarget>();
+    TII = Subtarget.getInstrInfo();
     MRI = &MF.getRegInfo();
-    MFI = MF.getInfo<WebAssemblyFunctionInfo>();
+    NumArgs = MF.getInfo<WebAssemblyFunctionInfo>()->getParams().size();
     return AsmPrinter::runOnMachineFunction(MF);
   }
 
@@ -79,8 +82,10 @@ private:
   void EmitEndOfAsmFile(Module &M) override;
 
   std::string getRegTypeName(unsigned RegNo) const;
+  static std::string toString(const APFloat &APF);
   const char *toString(MVT VT) const;
   std::string regToString(const MachineOperand &MO);
+  std::string argToString(const MachineOperand &MO);
 };
 
 } // end anonymous namespace
@@ -89,6 +94,36 @@ private:
 // 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})
@@ -99,12 +134,38 @@ std::string WebAssemblyAsmPrinter::getRegTypeName(unsigned RegNo) const {
   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);
 
-  return utostr(MFI->getWAReg(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(MVT VT) const {
@@ -142,22 +203,26 @@ void WebAssemblyAsmPrinter::EmitFunctionBodyStart() {
   SmallString<128> Str;
   raw_svector_ostream OS(Str);
 
-  for (MVT VT : MFI->getParams())
-    OS << "\t" ".param " << toString(VT) << '\n';
-  for (MVT VT : MFI->getResults())
-    OS << "\t" ".result " << toString(VT) << '\n';
+  for (MVT VT : MF->getInfo<WebAssemblyFunctionInfo>()->getParams())
+    OS << "\t" ".param "
+       << toString(VT) << '\n';
+  for (MVT VT : MF->getInfo<WebAssemblyFunctionInfo>()->getResults())
+    OS << "\t" ".result "
+       << toString(VT) << '\n';
 
   bool FirstVReg = true;
   for (unsigned Idx = 0, IdxE = MRI->getNumVirtRegs(); Idx != IdxE; ++Idx) {
     unsigned VReg = TargetRegisterInfo::index2VirtReg(Idx);
-    if (!MRI->use_empty(VReg)) {
-      if (FirstVReg)
-        OS << "\t" ".local ";
-      else
-        OS << ", ";
-      OS << getRegTypeName(VReg);
-      FirstVReg = false;
-    }
+    // FIXME: Don't skip dead virtual registers for now: that would require
+    //        remapping all locals' numbers.
+    // if (!MRI->use_empty(VReg)) {
+    if (FirstVReg)
+      OS << "\t" ".local ";
+    else
+      OS << ", ";
+    OS << getRegTypeName(VReg);
+    FirstVReg = false;
+    //}
   }
   if (!FirstVReg)
     OS << '\n';
@@ -171,36 +236,80 @@ void WebAssemblyAsmPrinter::EmitFunctionBodyStart() {
 
 void WebAssemblyAsmPrinter::EmitInstruction(const MachineInstr *MI) {
   DEBUG(dbgs() << "EmitInstruction: " << *MI << '\n');
+  SmallString<128> Str;
+  raw_svector_ostream OS(Str);
 
   unsigned NumDefs = MI->getDesc().getNumDefs();
   assert(NumDefs <= 1 &&
          "Instructions with multiple result values not implemented");
 
+  OS << '\t';
+
   switch (MI->getOpcode()) {
-  case TargetOpcode::COPY: {
-    // TODO: Figure out a way to lower COPY instructions to MCInst form.
-    SmallString<128> Str;
-    raw_svector_ostream OS(Str);
-    OS << "\t" "set_local " << regToString(MI->getOperand(0)) << ", "
-               "(get_local " << regToString(MI->getOperand(1)) << ")";
-    OutStreamer->EmitRawText(OS.str());
+  case TargetOpcode::COPY:
+    OS << "get_local push, " << regToString(MI->getOperand(1));
     break;
-  }
   case WebAssembly::ARGUMENT_I32:
   case WebAssembly::ARGUMENT_I64:
   case WebAssembly::ARGUMENT_F32:
   case WebAssembly::ARGUMENT_F64:
-    // These represent values which are live into the function entry, so there's
-    // no instruction to emit.
+    OS << "get_local push, " << argToString(MI->getOperand(1));
     break;
   default: {
-    WebAssemblyMCInstLower MCInstLowering(OutContext, *this);
-    MCInst TmpInst;
-    MCInstLowering.Lower(MI, TmpInst);
-    EmitToStreamer(*OutStreamer, TmpInst);
+    OS << OpcodeName(TII, MI);
+    bool NeedComma = false;
+    bool DefsPushed = false;
+    if (NumDefs != 0 && !MI->isCall()) {
+      OS << " push";
+      NeedComma = true;
+      DefsPushed = true;
+    }
+    for (const MachineOperand &MO : MI->uses()) {
+      if (MO.isReg() && MO.isImplicit())
+        continue;
+      if (NeedComma)
+        OS << ',';
+      NeedComma = true;
+      OS << ' ';
+      switch (MO.getType()) {
+      default:
+        llvm_unreachable("unexpected machine operand type");
+      case MachineOperand::MO_Register:
+        OS << "(get_local " << regToString(MO) << ')';
+        break;
+      case MachineOperand::MO_Immediate:
+        OS << MO.getImm();
+        break;
+      case MachineOperand::MO_FPImmediate:
+        OS << toString(MO.getFPImm()->getValueAPF());
+        break;
+      case MachineOperand::MO_GlobalAddress:
+        OS << toSymbol(MO.getGlobal()->getName());
+        break;
+      case MachineOperand::MO_MachineBasicBlock:
+        OS << toSymbol(MO.getMBB()->getSymbol()->getName());
+        break;
+      }
+      if (NumDefs != 0 && !DefsPushed) {
+        // Special-case for calls; print the push after the callee.
+        assert(MI->isCall());
+        OS << ", push";
+        DefsPushed = true;
+      }
+    }
     break;
   }
   }
+
+  OutStreamer->EmitRawText(OS.str());
+
+  if (NumDefs != 0) {
+    SmallString<128> Str;
+    raw_svector_ostream OS(Str);
+    const MachineOperand &Operand = MI->getOperand(0);
+    OS << "\tset_local " << regToString(Operand) << ", pop";
+    OutStreamer->EmitRawText(OS.str());
+  }
 }
 
 static void ComputeLegalValueVTs(LLVMContext &Context,
@@ -231,8 +340,8 @@ void WebAssemblyAsmPrinter::EmitEndOfAsmFile(Module &M) {
       if (Str.empty())
         OS << "\t.imports\n";
 
-      MCSymbol *Sym = OutStreamer->getContext().getOrCreateSymbol(F.getName());
-      OS << "\t.import " << *Sym << " \"\" " << *Sym;
+      OS << "\t.import " << toSymbol(F.getName()) << " \"\" \"" << F.getName()
+         << "\"";
 
       const WebAssemblyTargetLowering &TLI =
           *TM.getSubtarget<WebAssemblySubtarget>(F).getTargetLowering();