[RISCV] Add tune info for mem* expansion (#118439)

So that CPUs can tune these options.

Author: wangpc-pp

llvm/lib/Target/RISCV/RISCVISelLowering.cpp

@@ -1544,6 +1544,20 @@ RISCVTargetLowering::RISCVTargetLowering(const TargetMachine &TM,
   // corresponding branch. This information is used in CGP/SelectOpt to decide
   // when to convert selects into branches.
   PredictableSelectIsExpensive = Subtarget.predictableSelectIsExpensive();
+
+  MaxStoresPerMemsetOptSize = Subtarget.getMaxStoresPerMemset(/*OptSize=*/true);
+  MaxStoresPerMemset = Subtarget.getMaxStoresPerMemset(/*OptSize=*/false);
+
+  MaxGluedStoresPerMemcpy = Subtarget.getMaxGluedStoresPerMemcpy();
+  MaxStoresPerMemcpyOptSize = Subtarget.getMaxStoresPerMemcpy(/*OptSize=*/true);
+  MaxStoresPerMemcpy = Subtarget.getMaxStoresPerMemcpy(/*OptSize=*/false);
+
+  MaxStoresPerMemmoveOptSize =
+      Subtarget.getMaxStoresPerMemmove(/*OptSize=*/true);
+  MaxStoresPerMemmove = Subtarget.getMaxStoresPerMemmove(/*OptSize=*/false);
+
+  MaxLoadsPerMemcmpOptSize = Subtarget.getMaxLoadsPerMemcmp(/*OptSize=*/true);
+  MaxLoadsPerMemcmp = Subtarget.getMaxLoadsPerMemcmp(/*OptSize=*/false);
 }
 
 EVT RISCVTargetLowering::getSetCCResultType(const DataLayout &DL,

llvm/lib/Target/RISCV/RISCVProcessors.td

@@ -24,15 +24,32 @@ class RISCVTuneInfo {
 
   // Tail duplication threshold at -O3.
   bits<32> TailDupAggressiveThreshold = 6;
+
+  bits<32> MaxStoresPerMemsetOptSize = 4;
+  bits<32> MaxStoresPerMemset = 8;
+
+  bits<32> MaxGluedStoresPerMemcpy = 0;
+  bits<32> MaxStoresPerMemcpyOptSize = 4;
+  bits<32> MaxStoresPerMemcpy = 8;
+
+  bits<32> MaxStoresPerMemmoveOptSize = 4;
+  bits<32> MaxStoresPerMemmove = 8;
+
+  bits<32> MaxLoadsPerMemcmpOptSize = 4;
+  bits<32> MaxLoadsPerMemcmp = 8;
 }
 
 def RISCVTuneInfoTable : GenericTable {
   let FilterClass = "RISCVTuneInfo";
   let CppTypeName = "RISCVTuneInfo";
   let Fields = ["Name", "PrefFunctionAlignment", "PrefLoopAlignment",
-                "CacheLineSize", "PrefetchDistance",
-                "MinPrefetchStride", "MaxPrefetchIterationsAhead",
-                "MinimumJumpTableEntries", "TailDupAggressiveThreshold"];
+                "CacheLineSize", "PrefetchDistance", "MinPrefetchStride",
+                "MaxPrefetchIterationsAhead", "MinimumJumpTableEntries",
+                "TailDupAggressiveThreshold", "MaxStoresPerMemsetOptSize",
+                "MaxStoresPerMemset", "MaxGluedStoresPerMemcpy",
+                "MaxStoresPerMemcpyOptSize", "MaxStoresPerMemcpy",
+                "MaxStoresPerMemmoveOptSize", "MaxStoresPerMemmove",
+                "MaxLoadsPerMemcmpOptSize", "MaxLoadsPerMemcmp"];
 }
 
 def getRISCVTuneInfo : SearchIndex {

llvm/lib/Target/RISCV/RISCVSubtarget.h

@@ -53,6 +53,19 @@ struct RISCVTuneInfo {
 
   // Tail duplication threshold at -O3.
   unsigned TailDupAggressiveThreshold;
+
+  unsigned MaxStoresPerMemsetOptSize;
+  unsigned MaxStoresPerMemset;
+
+  unsigned MaxGluedStoresPerMemcpy;
+  unsigned MaxStoresPerMemcpyOptSize;
+  unsigned MaxStoresPerMemcpy;
+
+  unsigned MaxStoresPerMemmoveOptSize;
+  unsigned MaxStoresPerMemmove;
+
+  unsigned MaxLoadsPerMemcmpOptSize;
+  unsigned MaxLoadsPerMemcmp;
 };
 
 #define GET_RISCVTuneInfoTable_DECL
@@ -325,6 +338,30 @@ class RISCVSubtarget : public RISCVGenSubtargetInfo {
     return TuneInfo->TailDupAggressiveThreshold;
   }
 
+  unsigned getMaxStoresPerMemset(bool OptSize) const {
+    return OptSize ? TuneInfo->MaxStoresPerMemsetOptSize
+                   : TuneInfo->MaxStoresPerMemset;
+  }
+
+  unsigned getMaxGluedStoresPerMemcpy() const {
+    return TuneInfo->MaxGluedStoresPerMemcpy;
+  }
+
+  unsigned getMaxStoresPerMemcpy(bool OptSize) const {
+    return OptSize ? TuneInfo->MaxStoresPerMemcpyOptSize
+                   : TuneInfo->MaxStoresPerMemcpy;
+  }
+
+  unsigned getMaxStoresPerMemmove(bool OptSize) const {
+    return OptSize ? TuneInfo->MaxStoresPerMemmoveOptSize
+                   : TuneInfo->MaxStoresPerMemmove;
+  }
+
+  unsigned getMaxLoadsPerMemcmp(bool OptSize) const {
+    return OptSize ? TuneInfo->MaxLoadsPerMemcmpOptSize
+                   : TuneInfo->MaxLoadsPerMemcmp;
+  }
+
   void overrideSchedPolicy(MachineSchedPolicy &Policy,
                            unsigned NumRegionInstrs) const override;
 };