Add support to model pipeline bypass / forwarding.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@115005 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/utils/TableGen/SubtargetEmitter.cpp b/utils/TableGen/SubtargetEmitter.cpp
index 21870b1..03a813d 100644
--- a/utils/TableGen/SubtargetEmitter.cpp
+++ b/utils/TableGen/SubtargetEmitter.cpp
@@ -262,6 +262,24 @@
}
}
+void SubtargetEmitter::FormItineraryBypassString(const std::string &Name,
+ Record *ItinData,
+ std::string &ItinString,
+ unsigned NOperandCycles) {
+ const std::vector<Record*> &BypassList =
+ ItinData->getValueAsListOfDefs("Bypasses");
+ unsigned N = BypassList.size();
+ for (unsigned i = 0; i < N;) {
+ ItinString += Name + "Bypass::" + BypassList[i]->getName();
+ if (++i < N) ItinString += ", ";
+ }
+
+ for (; N < NOperandCycles;) {
+ ItinString += " 0";
+ if (++N < NOperandCycles) ItinString += ", ";
+ }
+}
+
//
// EmitStageAndOperandCycleData - Generate unique itinerary stages and
// operand cycle tables. Record itineraries for processors.
@@ -296,6 +314,16 @@
<< " = 1 << " << j << ";\n";
OS << "}\n";
+
+ std::vector<Record*> BPs = Proc->getValueAsListOfDefs("BP");
+ OS << "\n// Pipeline bypasses for itineraries \"" << Name << "\"\n"
+ << "namespace " << Name << "Bypass {\n";
+
+ for (unsigned j = 0, BPN = BPs.size(); j < BPN; ++j)
+ OS << " const unsigned " << BPs[j]->getName()
+ << " = 1 << " << j << ";\n";
+
+ OS << "}\n";
}
// Begin stages table
@@ -305,6 +333,10 @@
// Begin operand cycle table
std::string OperandCycleTable = "static const unsigned OperandCycles[] = {\n";
OperandCycleTable += " 0, // No itinerary\n";
+
+ // Begin pipeline bypass table
+ std::string BypassTable = "static const unsigned Bypasses[] = {\n";
+ BypassTable += " 0, // No itinerary\n";
unsigned StageCount = 1, OperandCycleCount = 1;
unsigned ItinStageEnum = 1, ItinOperandCycleEnum = 1;
@@ -342,6 +374,10 @@
FormItineraryOperandCycleString(ItinData, ItinOperandCycleString,
NOperandCycles);
+ std::string ItinBypassString;
+ FormItineraryBypassString(Name, ItinData, ItinBypassString,
+ NOperandCycles);
+
// Check to see if stage already exists and create if it doesn't
unsigned FindStage = 0;
if (NStages > 0) {
@@ -367,6 +403,11 @@
// Record Itin class number.
ItinOperandCycleMap[ItinOperandCycleString] =
FindOperandCycle = OperandCycleCount;
+
+ // Emit as bypass, // index
+ BypassTable += ItinBypassString + ", // " +
+ itostr(ItinOperandCycleEnum) + "\n";
+
OperandCycleCount += NOperandCycles;
ItinOperandCycleEnum++;
}
@@ -389,7 +430,7 @@
// Add process itinerary to list
ProcList.push_back(ItinList);
}
-
+
// Closing stage
StageTable += " { 0, 0, 0, llvm::InstrStage::Required } // End itinerary\n";
StageTable += "};\n";
@@ -398,9 +439,13 @@
OperandCycleTable += " 0 // End itinerary\n";
OperandCycleTable += "};\n";
+ BypassTable += " 0 // End itinerary\n";
+ BypassTable += "};\n";
+
// Emit tables.
OS << StageTable;
OS << OperandCycleTable;
+ OS << BypassTable;
// Emit size of tables
OS<<"\nenum {\n";