[llvm] [CodeGen][StaticDataPartitioning]Place local-linkage global variables in hot or unlikely prefixed sections based on profile information (PR #125756)

[Snehasish Kumar via llvm-commits]

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@@ -117,18 +164,37 @@ bool StaticDataSplitter::partitionStaticDataWithProfiles(MachineFunction &MF) {
           // Hotness is based on source basic block hotness.
           // TODO: PSI APIs are about instruction hotness. Introduce API for
           // data access hotness.
-          if (PSI->isColdBlock(&MBB, MBFI))
+          if (Count && PSI->isColdCount(*Count))
             Hotness = MachineFunctionDataHotness::Cold;
 
           if (MJTI->updateJumpTableEntryHotness(JTI, Hotness))
             ++NumChangedJumpTables;
+        } else if (const Constant *C = getConstant(Op, TM)) {
+          SDPI->addConstantProfileCount(C, Count);
         }
       }
     }
   }
   return NumChangedJumpTables > 0;
 }
 
+const GlobalVariable *
+StaticDataSplitter::getLocalLinkageGlobalVariable(const GlobalValue *GV) {
+  // LLVM IR Verifier requires that a declaration must have valid declaration
+  // linkage, and local linkages are not among the valid ones. So there is no
+  // need to check GV is not a declaration here.
+  return (GV && GV->hasLocalLinkage()) ? dyn_cast<GlobalVariable>(GV) : nullptr;
+}
+
+bool StaticDataSplitter::inStaticDataSection(const GlobalVariable *GV,
+                                             const TargetMachine &TM) {
+  assert(GV && "Caller guaranteed");
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snehasish wrote:

Change the param to a const & to avoid this assertion?

https://github.com/llvm/llvm-project/pull/125756