Subzero: Add necessary PNaCl files for standalone build.

pnacl-llvm/NaClBitCodes.cpp

+//===- NaClBitcodeHeader.cpp ----------------------------------------------===//
+//     PNaCl bitcode header reader.
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// Implementation of Bitcode abbrevations.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Bitcode/NaCl/NaClBitCodes.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm/Support/ErrorHandling.h"
+
+using namespace llvm;
+
+const bool NaClBitCodeAbbrevOp::HasValueArray[] = {
+  true,  // Literal
+  true,  // Fixed
+  true,  // VBR
+  false, // Array
+  false  // Char6
+};
+
+const char *NaClBitCodeAbbrevOp::EncodingNameArray[] = {
+  "Literal",
+  "Fixed",
+  "VBR",
+  "Array",
+  "Char6"
+};
+
+NaClBitCodeAbbrevOp::NaClBitCodeAbbrevOp(Encoding E, uint64_t Data)
+    : Enc(E), Val(Data) {
+  if (isValid(E, Data)) return;
+  std::string Buffer;
+  raw_string_ostream StrBuf(Buffer);
+  StrBuf << "Invalid NaClBitCodeAbbrevOp(" << E << ", " << Data << ")";
+  report_fatal_error(StrBuf.str());
+}
+
+bool NaClBitCodeAbbrevOp::isValid(Encoding E, uint64_t Val) {
+  switch (NaClBitCodeAbbrevOp::Encoding(E)) {
+  case Literal:
+    return true;
+  case Fixed:
+  case VBR:
+    return Val <= naclbitc::MaxAbbrevWidth;
+  case Char6:
+  case Array:
+    return Val == 0;
+  }
+  llvm_unreachable("unhandled abbreviation");
+}
+
+void NaClBitCodeAbbrevOp::Print(raw_ostream& Stream) const {
+  if (Enc == Literal) {
+    Stream << getValue();
+    return;
+  }
+  Stream << getEncodingName(Enc);
+  if (!hasValue())
+    return;
+  Stream << "(" << Val << ")";
+}
+
+static void PrintExpression(raw_ostream &Stream,
+                            const NaClBitCodeAbbrev *Abbrev,
+                            unsigned &Index) {
+  // Bail out early, in case we are incrementally building the
+  // expression and the argument is not available yet.
+  if (Index >= Abbrev->getNumOperandInfos()) return;
+
+  const NaClBitCodeAbbrevOp &Op = Abbrev->getOperandInfo(Index);
+  Op.Print(Stream);
+  if (unsigned NumArgs = Op.NumArguments()) {
+    Stream << "(";
+    for (unsigned i = 0; i < NumArgs; ++i) {
+      ++Index;
+      if (i > 0) Stream << ",";
+      PrintExpression(Stream, Abbrev, Index);
+    }
+    Stream << ")";
+  }
+}
+
+void NaClBitCodeAbbrev::Print(raw_ostream &Stream, bool AddNewLine) const {
+  Stream << "[";
+  for (unsigned i = 0; i < getNumOperandInfos(); ++i) {
+    if (i > 0) Stream << ", ";
+    PrintExpression(Stream, this, i);
+  }
+  Stream << "]";
+  if (AddNewLine) Stream << "\n";
+}
+
+NaClBitCodeAbbrev *NaClBitCodeAbbrev::Simplify() const {
+  NaClBitCodeAbbrev *Abbrev = new NaClBitCodeAbbrev();
+  for (unsigned i = 0; i < OperandList.size(); ++i) {
+    const NaClBitCodeAbbrevOp &Op = OperandList[i];
+    // Simplify if possible.  Currently, the only simplification known
+    // is to remove unnecessary operands appearing immediately before an
+    // array operator. That is, apply the simplification:
+    //    Op Array(Op) -> Array(Op)
+    assert(!Op.isArrayOp() || i == OperandList.size()-2);
+    while (Op.isArrayOp() && !Abbrev->OperandList.empty() &&
+           Abbrev->OperandList.back() == OperandList[i+1]) {
+      Abbrev->OperandList.pop_back();
+    }
+    Abbrev->OperandList.push_back(Op);
+  }
+  return Abbrev;
+}
+
+bool NaClBitCodeAbbrev::isValid() const {
+  // Verify that an array op appears can only appear if it is the
+  // second to last element.
+  unsigned NumOperands = getNumOperandInfos();
+  if (NumOperands == 0) return false;
+  for (unsigned i = 0; i < NumOperands; ++i) {
+    const NaClBitCodeAbbrevOp &Op = getOperandInfo(i);
+    if (Op.isArrayOp() && i + 2 != NumOperands)
+      // Note: Unlike LLVM bitcode, we allow literals in arrays!
+      return false;
+  }
+  return true;
+}