[MemProf] Use DenseMap for call map (NFC) (#151161)

There is no reason to use std::map for the call maps maintained for
function clones during function clone assignment, as we don't iterate
over them and don't need deterministic ordering, so use the more
efficient DenseMap.

Author: teresajohnson

llvm/lib/Transforms/IPO/MemProfContextDisambiguation.cpp

@@ -732,7 +732,7 @@ class CallsiteContextGraph {
   /// of the functions tracked calls to their new versions in the CallMap.
   /// Assigns new clones to clone number CloneNo.
   FuncInfo cloneFunctionForCallsite(
-      FuncInfo &Func, CallInfo &Call, std::map<CallInfo, CallInfo> &CallMap,
+      FuncInfo &Func, CallInfo &Call, DenseMap<CallInfo, CallInfo> &CallMap,
       std::vector<CallInfo> &CallsWithMetadataInFunc, unsigned CloneNo) {
     return static_cast<DerivedCCG *>(this)->cloneFunctionForCallsite(
         Func, Call, CallMap, CallsWithMetadataInFunc, CloneNo);
@@ -899,7 +899,7 @@ class ModuleCallsiteContextGraph
   CallsiteContextGraph<ModuleCallsiteContextGraph, Function,
                        Instruction *>::FuncInfo
   cloneFunctionForCallsite(FuncInfo &Func, CallInfo &Call,
-                           std::map<CallInfo, CallInfo> &CallMap,
+                           DenseMap<CallInfo, CallInfo> &CallMap,
                            std::vector<CallInfo> &CallsWithMetadataInFunc,
                            unsigned CloneNo);
   std::string getLabel(const Function *Func, const Instruction *Call,
@@ -991,7 +991,7 @@ class IndexCallsiteContextGraph
   CallsiteContextGraph<IndexCallsiteContextGraph, FunctionSummary,
                        IndexCall>::FuncInfo
   cloneFunctionForCallsite(FuncInfo &Func, CallInfo &Call,
-                           std::map<CallInfo, CallInfo> &CallMap,
+                           DenseMap<CallInfo, CallInfo> &CallMap,
                            std::vector<CallInfo> &CallsWithMetadataInFunc,
                            unsigned CloneNo);
   std::string getLabel(const FunctionSummary *Func, const IndexCall &Call,
@@ -4062,7 +4062,7 @@ static void updateSubprogramLinkageName(Function *NewFunc, StringRef Name) {
 CallsiteContextGraph<ModuleCallsiteContextGraph, Function,
                      Instruction *>::FuncInfo
 ModuleCallsiteContextGraph::cloneFunctionForCallsite(
-    FuncInfo &Func, CallInfo &Call, std::map<CallInfo, CallInfo> &CallMap,
+    FuncInfo &Func, CallInfo &Call, DenseMap<CallInfo, CallInfo> &CallMap,
     std::vector<CallInfo> &CallsWithMetadataInFunc, unsigned CloneNo) {
   // Use existing LLVM facilities for cloning and obtaining Call in clone
   ValueToValueMapTy VMap;
@@ -4085,7 +4085,7 @@ ModuleCallsiteContextGraph::cloneFunctionForCallsite(
 CallsiteContextGraph<IndexCallsiteContextGraph, FunctionSummary,
                      IndexCall>::FuncInfo
 IndexCallsiteContextGraph::cloneFunctionForCallsite(
-    FuncInfo &Func, CallInfo &Call, std::map<CallInfo, CallInfo> &CallMap,
+    FuncInfo &Func, CallInfo &Call, DenseMap<CallInfo, CallInfo> &CallMap,
     std::vector<CallInfo> &CallsWithMetadataInFunc, unsigned CloneNo) {
   // Check how many clones we have of Call (and therefore function).
   // The next clone number is the current size of versions array.
@@ -4506,7 +4506,7 @@ bool CallsiteContextGraph<DerivedCCG, FuncTy, CallTy>::assignFunctions() {
     FuncInfo FuncClone;
     // Remappings of each call of interest (from original uncloned call to the
     // corresponding cloned call in this function clone).
-    std::map<CallInfo, CallInfo> CallMap;
+    DenseMap<CallInfo, CallInfo> CallMap;
   };
 
   // Walk all functions for which we saw calls with memprof metadata, and handle
@@ -4542,7 +4542,7 @@ bool CallsiteContextGraph<DerivedCCG, FuncTy, CallTy>::assignFunctions() {
         FuncCloneToCurNodeCloneMap[FuncClone] = CallsiteClone;
 
         assert(FuncCloneInfos.size() > FuncClone.cloneNo());
-        std::map<CallInfo, CallInfo> &CallMap =
+        DenseMap<CallInfo, CallInfo> &CallMap =
             FuncCloneInfos[FuncClone.cloneNo()].CallMap;
         CallInfo CallClone(Call);
         if (auto It = CallMap.find(Call); It != CallMap.end())
@@ -4594,7 +4594,8 @@ bool CallsiteContextGraph<DerivedCCG, FuncTy, CallTy>::assignFunctions() {
                 }));
             // Initialize with empty call map, assign Clone to original function
             // and its callers, and skip to the next clone.
-            FuncCloneInfos.push_back({OrigFunc, {}});
+            FuncCloneInfos.push_back(
+                {OrigFunc, DenseMap<CallInfo, CallInfo>()});
             AssignCallsiteCloneToFuncClone(
                 OrigFunc, Call, Clone,
                 AllocationCallToContextNodeMap.count(Call));
@@ -4627,7 +4628,7 @@ bool CallsiteContextGraph<DerivedCCG, FuncTy, CallTy>::assignFunctions() {
 
           // Clone function and save it along with the CallInfo map created
           // during cloning in the FuncCloneInfos.
-          std::map<CallInfo, CallInfo> NewCallMap;
+          DenseMap<CallInfo, CallInfo> NewCallMap;
           unsigned CloneNo = FuncCloneInfos.size();
           assert(CloneNo > 0 && "Clone 0 is the original function, which "
                                 "should already exist in the map");
@@ -4734,7 +4735,7 @@ bool CallsiteContextGraph<DerivedCCG, FuncTy, CallTy>::assignFunctions() {
               // CallMap is set up as indexed by original Call at clone 0.
               CallInfo OrigCall(Callee->getOrigNode()->Call);
               OrigCall.setCloneNo(0);
-              std::map<CallInfo, CallInfo> &CallMap =
+              DenseMap<CallInfo, CallInfo> &CallMap =
                   FuncCloneInfos[NewFuncClone.cloneNo()].CallMap;
               assert(CallMap.count(OrigCall));
               CallInfo NewCall(CallMap[OrigCall]);