[tablegen] Avoid creating a temporary vector in getInstructionCase
Record::getValues returns ArrayRef which has a cast operator
to std::vector, as a result a temporary vector is created
if the type of the variable is const std::vector&
that is suboptimal in this case.
Differential revision: https://reviews.llvm.org/D34969
Test plan: make check-all
llvm-svn: 307063
diff --git a/llvm/utils/TableGen/CodeEmitterGen.cpp b/llvm/utils/TableGen/CodeEmitterGen.cpp
index b80dd5d..23751a2 100644
--- a/llvm/utils/TableGen/CodeEmitterGen.cpp
+++ b/llvm/utils/TableGen/CodeEmitterGen.cpp
@@ -187,20 +187,18 @@
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) {
+ for (const RecordVal &RV : R->getValues()) {
unsigned OpIdx;
- if (!CGI.Operands.hasOperandNamed(Vals[i].getName(), OpIdx))
+ if (!CGI.Operands.hasOperandNamed(RV.getName(), OpIdx))
continue;
NamedOpIndices.insert(OpIdx);
@@ -209,13 +207,13 @@
// 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) {
+ for (const RecordVal &RV : R->getValues()) {
// Ignore fixed fields in the record, we're looking for values like:
// bits<5> RST = { ?, ?, ?, ?, ? };
- if (Vals[i].getPrefix() || Vals[i].getValue()->isComplete())
+ if (RV.getPrefix() || RV.getValue()->isComplete())
continue;
- AddCodeToMergeInOperand(R, BI, Vals[i].getName(), NumberedOp,
+ AddCodeToMergeInOperand(R, BI, RV.getName(), NumberedOp,
NamedOpIndices, Case, Target);
}