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diff --git a/contrib/llvm/utils/TableGen/CodeEmitterGen.cpp b/contrib/llvm/utils/TableGen/CodeEmitterGen.cpp
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+//===- CodeEmitterGen.cpp - Code Emitter Generator ------------------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// CodeEmitterGen uses the descriptions of instructions and their fields to
+// construct an automated code emitter: a function that, given a MachineInstr,
+// returns the (currently, 32-bit unsigned) value of the instruction.
+//
+//===----------------------------------------------------------------------===//
+
+#include "CodeGenTarget.h"
+#include "llvm/ADT/StringExtras.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/TableGen/Record.h"
+#include "llvm/TableGen/TableGenBackend.h"
+#include <map>
+#include <string>
+#include <vector>
+using namespace llvm;
+
+namespace {
+
+class CodeEmitterGen {
+ RecordKeeper &Records;
+public:
+ CodeEmitterGen(RecordKeeper &R) : Records(R) {}
+
+ void run(raw_ostream &o);
+private:
+ int getVariableBit(const std::string &VarName, BitsInit *BI, int bit);
+ std::string getInstructionCase(Record *R, CodeGenTarget &Target);
+ void AddCodeToMergeInOperand(Record *R, BitsInit *BI,
+ const std::string &VarName,
+ unsigned &NumberedOp,
+ std::set<unsigned> &NamedOpIndices,
+ std::string &Case, CodeGenTarget &Target);
+
+};
+
+// If the VarBitInit at position 'bit' matches the specified variable then
+// return the variable bit position. Otherwise return -1.
+int CodeEmitterGen::getVariableBit(const std::string &VarName,
+ BitsInit *BI, int bit) {
+ if (VarBitInit *VBI = dyn_cast<VarBitInit>(BI->getBit(bit))) {
+ if (VarInit *VI = dyn_cast<VarInit>(VBI->getBitVar()))
+ if (VI->getName() == VarName)
+ return VBI->getBitNum();
+ } else if (VarInit *VI = dyn_cast<VarInit>(BI->getBit(bit))) {
+ if (VI->getName() == VarName)
+ return 0;
+ }
+
+ return -1;
+}
+
+void CodeEmitterGen::
+AddCodeToMergeInOperand(Record *R, BitsInit *BI, const std::string &VarName,
+ unsigned &NumberedOp,
+ std::set<unsigned> &NamedOpIndices,
+ std::string &Case, CodeGenTarget &Target) {
+ CodeGenInstruction &CGI = Target.getInstruction(R);
+
+ // Determine if VarName actually contributes to the Inst encoding.
+ int bit = BI->getNumBits()-1;
+
+ // Scan for a bit that this contributed to.
+ for (; bit >= 0; ) {
+ if (getVariableBit(VarName, BI, bit) != -1)
+ break;
+
+ --bit;
+ }
+
+ // If we found no bits, ignore this value, otherwise emit the call to get the
+ // operand encoding.
+ if (bit < 0) return;
+
+ // If the operand matches by name, reference according to that
+ // operand number. Non-matching operands are assumed to be in
+ // order.
+ unsigned OpIdx;
+ if (CGI.Operands.hasOperandNamed(VarName, OpIdx)) {
+ // Get the machine operand number for the indicated operand.
+ OpIdx = CGI.Operands[OpIdx].MIOperandNo;
+ assert(!CGI.Operands.isFlatOperandNotEmitted(OpIdx) &&
+ "Explicitly used operand also marked as not emitted!");
+ } else {
+ unsigned NumberOps = CGI.Operands.size();
+ /// If this operand is not supposed to be emitted by the
+ /// generated emitter, skip it.
+ while (NumberedOp < NumberOps &&
+ (CGI.Operands.isFlatOperandNotEmitted(NumberedOp) ||
+ (!NamedOpIndices.empty() && NamedOpIndices.count(
+ CGI.Operands.getSubOperandNumber(NumberedOp).first)))) {
+ ++NumberedOp;
+
+ if (NumberedOp >= CGI.Operands.back().MIOperandNo +
+ CGI.Operands.back().MINumOperands) {
+ errs() << "Too few operands in record " << R->getName() <<
+ " (no match for variable " << VarName << "):\n";
+ errs() << *R;
+ errs() << '\n';
+
+ return;
+ }
+ }
+
+ OpIdx = NumberedOp++;
+ }
+
+ std::pair<unsigned, unsigned> SO = CGI.Operands.getSubOperandNumber(OpIdx);
+ std::string &EncoderMethodName = CGI.Operands[SO.first].EncoderMethodName;
+
+ // If the source operand has a custom encoder, use it. This will
+ // get the encoding for all of the suboperands.
+ if (!EncoderMethodName.empty()) {
+ // A custom encoder has all of the information for the
+ // sub-operands, if there are more than one, so only
+ // query the encoder once per source operand.
+ if (SO.second == 0) {
+ Case += " // op: " + VarName + "\n" +
+ " op = " + EncoderMethodName + "(MI, " + utostr(OpIdx);
+ Case += ", Fixups, STI";
+ Case += ");\n";
+ }
+ } else {
+ Case += " // op: " + VarName + "\n" +
+ " op = getMachineOpValue(MI, MI.getOperand(" + utostr(OpIdx) + ")";
+ Case += ", Fixups, STI";
+ Case += ");\n";
+ }
+
+ for (; bit >= 0; ) {
+ int varBit = getVariableBit(VarName, BI, bit);
+
+ // If this bit isn't from a variable, skip it.
+ if (varBit == -1) {
+ --bit;
+ continue;
+ }
+
+ // Figure out the consecutive range of bits covered by this operand, in
+ // order to generate better encoding code.
+ int beginInstBit = bit;
+ int beginVarBit = varBit;
+ int N = 1;
+ for (--bit; bit >= 0;) {
+ varBit = getVariableBit(VarName, BI, bit);
+ if (varBit == -1 || varBit != (beginVarBit - N)) break;
+ ++N;
+ --bit;
+ }
+
+ uint64_t opMask = ~(uint64_t)0 >> (64-N);
+ int opShift = beginVarBit - N + 1;
+ opMask <<= opShift;
+ opShift = beginInstBit - beginVarBit;
+
+ if (opShift > 0) {
+ Case += " Value |= (op & UINT64_C(" + utostr(opMask) + ")) << " +
+ itostr(opShift) + ";\n";
+ } else if (opShift < 0) {
+ Case += " Value |= (op & UINT64_C(" + utostr(opMask) + ")) >> " +
+ itostr(-opShift) + ";\n";
+ } else {
+ Case += " Value |= op & UINT64_C(" + utostr(opMask) + ");\n";
+ }
+ }
+}
+
+
+std::string CodeEmitterGen::getInstructionCase(Record *R,
+ CodeGenTarget &Target) {
+ std::string Case;
+
+ BitsInit *BI = R->getValueAsBitsInit("Inst");
+ const std::vector<RecordVal> &Vals = R->getValues();
+ unsigned NumberedOp = 0;
+
+ std::set<unsigned> NamedOpIndices;
+ // Collect the set of operand indices that might correspond to named
+ // operand, and skip these when assigning operands based on position.
+ if (Target.getInstructionSet()->
+ getValueAsBit("noNamedPositionallyEncodedOperands")) {
+ CodeGenInstruction &CGI = Target.getInstruction(R);
+ for (unsigned i = 0, e = Vals.size(); i != e; ++i) {
+ unsigned OpIdx;
+ if (!CGI.Operands.hasOperandNamed(Vals[i].getName(), OpIdx))
+ continue;
+
+ NamedOpIndices.insert(OpIdx);
+ }
+ }
+
+ // Loop over all of the fields in the instruction, determining which are the
+ // operands to the instruction.
+ for (unsigned i = 0, e = Vals.size(); i != e; ++i) {
+ // Ignore fixed fields in the record, we're looking for values like:
+ // bits<5> RST = { ?, ?, ?, ?, ? };
+ if (Vals[i].getPrefix() || Vals[i].getValue()->isComplete())
+ continue;
+
+ AddCodeToMergeInOperand(R, BI, Vals[i].getName(), NumberedOp,
+ NamedOpIndices, Case, Target);
+ }
+
+ std::string PostEmitter = R->getValueAsString("PostEncoderMethod");
+ if (!PostEmitter.empty()) {
+ Case += " Value = " + PostEmitter + "(MI, Value";
+ Case += ", STI";
+ Case += ");\n";
+ }
+
+ return Case;
+}
+
+void CodeEmitterGen::run(raw_ostream &o) {
+ CodeGenTarget Target(Records);
+ std::vector<Record*> Insts = Records.getAllDerivedDefinitions("Instruction");
+
+ // For little-endian instruction bit encodings, reverse the bit order
+ Target.reverseBitsForLittleEndianEncoding();
+
+ const std::vector<const CodeGenInstruction*> &NumberedInstructions =
+ Target.getInstructionsByEnumValue();
+
+ // Emit function declaration
+ o << "uint64_t " << Target.getName();
+ o << "MCCodeEmitter::getBinaryCodeForInstr(const MCInst &MI,\n"
+ << " SmallVectorImpl<MCFixup> &Fixups,\n"
+ << " const MCSubtargetInfo &STI) const {\n";
+
+ // Emit instruction base values
+ o << " static const uint64_t InstBits[] = {\n";
+ for (std::vector<const CodeGenInstruction*>::const_iterator
+ IN = NumberedInstructions.begin(),
+ EN = NumberedInstructions.end();
+ IN != EN; ++IN) {
+ const CodeGenInstruction *CGI = *IN;
+ Record *R = CGI->TheDef;
+
+ if (R->getValueAsString("Namespace") == "TargetOpcode" ||
+ R->getValueAsBit("isPseudo")) {
+ o << " UINT64_C(0),\n";
+ continue;
+ }
+
+ BitsInit *BI = R->getValueAsBitsInit("Inst");
+
+ // Start by filling in fixed values.
+ uint64_t Value = 0;
+ for (unsigned i = 0, e = BI->getNumBits(); i != e; ++i) {
+ if (BitInit *B = dyn_cast<BitInit>(BI->getBit(e-i-1)))
+ Value |= (uint64_t)B->getValue() << (e-i-1);
+ }
+ o << " UINT64_C(" << Value << ")," << '\t' << "// " << R->getName() << "\n";
+ }
+ o << " UINT64_C(0)\n };\n";
+
+ // Map to accumulate all the cases.
+ std::map<std::string, std::vector<std::string> > CaseMap;
+
+ // Construct all cases statement for each opcode
+ for (std::vector<Record*>::iterator IC = Insts.begin(), EC = Insts.end();
+ IC != EC; ++IC) {
+ Record *R = *IC;
+ if (R->getValueAsString("Namespace") == "TargetOpcode" ||
+ R->getValueAsBit("isPseudo"))
+ continue;
+ const std::string &InstName = R->getValueAsString("Namespace") + "::"
+ + R->getName();
+ std::string Case = getInstructionCase(R, Target);
+
+ CaseMap[Case].push_back(InstName);
+ }
+
+ // Emit initial function code
+ o << " const unsigned opcode = MI.getOpcode();\n"
+ << " uint64_t Value = InstBits[opcode];\n"
+ << " uint64_t op = 0;\n"
+ << " (void)op; // suppress warning\n"
+ << " switch (opcode) {\n";
+
+ // Emit each case statement
+ std::map<std::string, std::vector<std::string> >::iterator IE, EE;
+ for (IE = CaseMap.begin(), EE = CaseMap.end(); IE != EE; ++IE) {
+ const std::string &Case = IE->first;
+ std::vector<std::string> &InstList = IE->second;
+
+ for (int i = 0, N = InstList.size(); i < N; i++) {
+ if (i) o << "\n";
+ o << " case " << InstList[i] << ":";
+ }
+ o << " {\n";
+ o << Case;
+ o << " break;\n"
+ << " }\n";
+ }
+
+ // Default case: unhandled opcode
+ o << " default:\n"
+ << " std::string msg;\n"
+ << " raw_string_ostream Msg(msg);\n"
+ << " Msg << \"Not supported instr: \" << MI;\n"
+ << " report_fatal_error(Msg.str());\n"
+ << " }\n"
+ << " return Value;\n"
+ << "}\n\n";
+}
+
+} // End anonymous namespace
+
+namespace llvm {
+
+void EmitCodeEmitter(RecordKeeper &RK, raw_ostream &OS) {
+ emitSourceFileHeader("Machine Code Emitter", OS);
+ CodeEmitterGen(RK).run(OS);
+}
+
+} // End llvm namespace
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