RPCS3/llvm
1
0
Fork 0
mirror of https://github.com/RPCS3/llvm.git synced 2025-01-16 15:08:59 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

split the giant encoder loop into two new helper functions.

Browse Source 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119129 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2010-11-15 06:59:17 +00:00
parent 98e969ae20
commit 1620117f76
2 changed files with 129 additions and 112 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

234
utils/TableGen/CodeEmitterGen.cpp
View File

@ -61,7 +61,7 @@ void CodeEmitterGen::reverseBits(std::vector<Record*> &Insts) {
// 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) {
BitsInit *BI, int bit) {
if (VarBitInit *VBI = dynamic_cast<VarBitInit*>(BI->getBit(bit)))
if (VarInit *VI = dynamic_cast<VarInit*>(VBI->getVariable()))
if (VI->getName() == VarName)
@ -70,6 +70,123 @@ int CodeEmitterGen::getVariableBit(const std::string &VarName,
return -1;
}
void CodeEmitterGen::
AddCodeToMergeInOperand(Record *R, BitsInit *BI, const std::string &VarName,
unsigned &NumberedOp,
std::string &Case, CodeGenTarget &Target) {
bool gotOp = false;
CodeGenInstruction &CGI = Target.getInstruction(R);
for (int bit = BI->getNumBits()-1; 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 consequtive 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;
}
if (!gotOp) {
// 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 {
/// If this operand is not supposed to be emitted by the
/// generated emitter, skip it.
while (CGI.Operands.isFlatOperandNotEmitted(NumberedOp))
++NumberedOp;
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);
if (MCEmitter)
Case += ", Fixups";
Case += ");\n";
}
} else {
Case += " // op: " + VarName + "\n" +
" op = getMachineOpValue(MI, MI.getOperand(" +
utostr(OpIdx) + ")";
if (MCEmitter)
Case += ", Fixups";
Case += ");\n";
}
gotOp = true;
}
unsigned opMask = ~0U >> (32-N);
int opShift = beginVarBit - N + 1;
opMask <<= opShift;
opShift = beginInstBit - beginVarBit;
if (opShift > 0) {
Case += " Value |= (op & " + utostr(opMask) + "U) << " +
itostr(opShift) + ";\n";
} else if (opShift < 0) {
Case += " Value |= (op & " + utostr(opMask) + "U) >> " +
itostr(-opShift) + ";\n";
} else {
Case += " Value |= op & " + utostr(opMask) + "U;\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;
// 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, Case, Target);
}
std::string PostEmitter = R->getValueAsString("PostEncoderMethod");
if (!PostEmitter.empty())
Case += " Value = " + PostEmitter + "(MI, Value);\n";
return Case;
}
void CodeEmitterGen::run(raw_ostream &o) {
CodeGenTarget Target;
std::vector<Record*> Insts = Records.getAllDerivedDefinitions("Instruction");
@ -107,12 +224,11 @@ void CodeEmitterGen::run(raw_ostream &o) {
BitsInit *BI = R->getValueAsBitsInit("Inst");
// Start by filling in fixed values...
// Start by filling in fixed values.
unsigned Value = 0;
for (unsigned i = 0, e = BI->getNumBits(); i != e; ++i) {
if (BitInit *B = dynamic_cast<BitInit*>(BI->getBit(e-i-1))) {
if (BitInit *B = dynamic_cast<BitInit*>(BI->getBit(e-i-1)))
Value |= B->getValue() << (e-i-1);
}
}
o << " " << Value << "U," << '\t' << "// " << R->getName() << "\n";
}
@ -128,115 +244,9 @@ void CodeEmitterGen::run(raw_ostream &o) {
if (R->getValueAsString("Namespace") == "TargetOpcode")
continue;
const std::string &InstName = R->getName();
std::string Case("");
std::string Case = getInstructionCase(R, Target);
BitsInit *BI = R->getValueAsBitsInit("Inst");
const std::vector<RecordVal> &Vals = R->getValues();
CodeGenInstruction &CGI = Target.getInstruction(R);
// Loop over all of the fields in the instruction, determining which are the
// operands to the instruction.
unsigned NumberedOp = 0;
for (unsigned i = 0, e = Vals.size(); i != e; ++i) {
// Ignore fixed fields.
if (Vals[i].getPrefix() || Vals[i].getValue()->isComplete())
continue;
// Is the operand continuous? If so, we can just mask and OR it in
// instead of doing it bit-by-bit, saving a lot in runtime cost.
const std::string &VarName = Vals[i].getName();
bool gotOp = false;
for (int bit = BI->getNumBits()-1; bit >= 0; ) {
int varBit = getVariableBit(VarName, BI, bit);
// If this bit isn't from a variable, skip it.
if (varBit == -1) {
--bit;
continue;
}
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;
}
if (!gotOp) {
// 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 {
/// If this operand is not supposed to be emitted by the
/// generated emitter, skip it.
while (CGI.Operands.isFlatOperandNotEmitted(NumberedOp))
++NumberedOp;
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);
if (MCEmitter)
Case += ", Fixups";
Case += ");\n";
}
} else {
Case += " // op: " + VarName + "\n"
+ " op = getMachineOpValue(MI, MI.getOperand("
+ utostr(OpIdx) + ")";
if (MCEmitter)
Case += ", Fixups";
Case += ");\n";
}
gotOp = true;
}
unsigned opMask = ~0U >> (32-N);
int opShift = beginVarBit - N + 1;
opMask <<= opShift;
opShift = beginInstBit - beginVarBit;
if (opShift > 0) {
Case += " Value |= (op & " + utostr(opMask) + "U) << "
+ itostr(opShift) + ";\n";
} else if (opShift < 0) {
Case += " Value |= (op & " + utostr(opMask) + "U) >> "
+ itostr(-opShift) + ";\n";
} else {
Case += " Value |= op & " + utostr(opMask) + "U;\n";
}
}
}
std::string PostEmitter = R->getValueAsString("PostEncoderMethod");
if (!PostEmitter.empty())
Case += " Value = " + PostEmitter + "(MI, Value);\n";
std::vector<std::string> &InstList = CaseMap[Case];
InstList.push_back(InstName);
CaseMap[Case].push_back(InstName);
}
// Emit initial function code

7
utils/TableGen/CodeEmitterGen.h
View File

@ -23,6 +23,7 @@ namespace llvm {
class RecordVal;
class BitsInit;
class CodeGenTarget;
class CodeEmitterGen : public TableGenBackend {
RecordKeeper &Records;
@ -36,6 +37,12 @@ private:
void emitGetValueBit(raw_ostream &o, const std::string &Namespace);
void reverseBits(std::vector<Record*> &Insts);
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::string &Case, CodeGenTarget &Target);
};
} // End llvm namespace