refactor(codegen): share array metadata registration

DECLARE and array-parameter binding both computed the dimension
multipliers, filled the same ArrayMetadata and stored it in ArrayTable.
Move that into a private ArrayHandler::defineMetadata helper that also
yields the total element count.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

3 files changed, 26 insertions, 25 deletions

diff --git a/include/cps/ArrayHandler.h b/include/cps/ArrayHandler.h
index 8ba631f..a09e708 100644
--- a/include/cps/ArrayHandler.h
+++ b/include/cps/ArrayHandler.h
@@ -47,6 +47,11 @@ class ArrayHandler {
                                    const std::vector<llvm::Value*> &Highs,
                                    std::vector<llvm::Value*> &Multipliers,
                                    llvm::Value *&TotalElements);
+    // Computes the bounds math, then fills and registers Name's metadata.
+    const ArrayMetadata &defineMetadata(const std::string &Name, const TypeInfo *ElemInfo,
+                                        std::vector<llvm::Value*> Lows,
+                                        std::vector<llvm::Value*> Highs,
+                                        llvm::Value *&TotalElements);
     bool emitCheckedIndices(const std::string &Name,
                             const std::vector<std::unique_ptr<ExprAST>> &IndexExprs,
                             int Line,
diff --git a/lib/CodeGen/ArrayHandler.cc b/lib/CodeGen/ArrayHandler.cc
index bfe6a78..de07ff7 100644
--- a/lib/CodeGen/ArrayHandler.cc
+++ b/lib/CodeGen/ArrayHandler.cc
@@ -78,7 +78,6 @@ Value *ArrayHandler::getElementPointer(const std::string &Name, Value *Offset) {
 
 void ArrayHandler::emitArrayDeclare(ArrayDeclareStmtAST *Stmt, CodeGen &CG) {
     std::string Name = Stmt->getName();
-    int Rank = static_cast<int>(Stmt->getBounds().size());
 
     const TypeInfo *ElemInfo = Types.resolve(Stmt->getType());
     if (!ElemInfo || !ElemInfo->LLVMType || ElemInfo->isVoid()) {
@@ -113,19 +112,9 @@ void ArrayHandler::emitArrayDeclare(ArrayDeclareStmtAST *Stmt, CodeGen &CG) {
         Highs.push_back(R);
     }
 
-    std::vector<Value*> Multipliers;
     Value *TotalElements = nullptr;
-    computeDimsAndMultipliers(Name, Lows, Highs, Multipliers, TotalElements);
-
-    ArrayMetadata Meta;
-    Meta.Rank = Rank;
-    Meta.ElementTypeName = ElemInfo->Name;
-    Meta.ElementType = ElemInfo->LLVMType;
-    Meta.ElementSizeC = Types.getSizeOfConstant(ElemInfo->LLVMType);
-    Meta.LowerBounds = std::move(Lows);
-    Meta.UpperBounds = std::move(Highs);
-    Meta.Multipliers = std::move(Multipliers);
-    ArrayTable[Name] = Meta;
+    const ArrayMetadata &Meta =
+        defineMetadata(Name, ElemInfo, std::move(Lows), std::move(Highs), TotalElements);
 
     Value *TotalBytes = Builder->CreateMul(TotalElements, Meta.ElementSizeC, Name + "_total_bytes");
     CallInst *Ptr = Builder->CreateCall(MallocFunc, TotalBytes, Name + "_malloc");
@@ -161,6 +150,24 @@ void ArrayHandler::emitArrayDeclare(ArrayDeclareStmtAST *Stmt, CodeGen &CG) {
     CG.activateStackObject(Lifetime, TotalElements);
 }
 
+const ArrayMetadata &ArrayHandler::defineMetadata(const std::string &Name, const TypeInfo *ElemInfo,
+                                                 std::vector<Value*> Lows,
+                                                 std::vector<Value*> Highs,
+                                                 Value *&TotalElements) {
+    std::vector<Value*> Multipliers;
+    computeDimsAndMultipliers(Name, Lows, Highs, Multipliers, TotalElements);
+
+    ArrayMetadata Meta;
+    Meta.Rank = static_cast<int>(Lows.size());
+    Meta.ElementTypeName = ElemInfo->Name;
+    Meta.ElementType = ElemInfo->LLVMType;
+    Meta.ElementSizeC = Types.getSizeOfConstant(ElemInfo->LLVMType);
+    Meta.LowerBounds = std::move(Lows);
+    Meta.UpperBounds = std::move(Highs);
+    Meta.Multipliers = std::move(Multipliers);
+    return ArrayTable[Name] = std::move(Meta);
+}
+
 void ArrayHandler::computeDimsAndMultipliers(const std::string &Name,
                                              const std::vector<Value*> &Lows,
                                              const std::vector<Value*> &Highs,
diff --git a/lib/CodeGen/ArrayParameters.cc b/lib/CodeGen/ArrayParameters.cc
index 4f2d54d..57cf6dd 100644
--- a/lib/CodeGen/ArrayParameters.cc
+++ b/lib/CodeGen/ArrayParameters.cc
@@ -21,19 +21,8 @@ void ArrayHandler::bindArrayParameter(const std::string &Name,
         return;
     }
 
-    std::vector<Value*> Multipliers;
     Value *TotalElements = nullptr;
-    computeDimsAndMultipliers(Name, LBs, UBs, Multipliers, TotalElements);
-
-    ArrayMetadata Meta;
-    Meta.Rank = static_cast<int>(LBs.size());
-    Meta.ElementTypeName = ElemInfo->Name;
-    Meta.ElementType = ElemInfo->LLVMType;
-    Meta.ElementSizeC = Types.getSizeOfConstant(ElemInfo->LLVMType);
-    Meta.LowerBounds = LBs;
-    Meta.UpperBounds = UBs;
-    Meta.Multipliers = std::move(Multipliers);
-    ArrayTable[Name] = Meta;
+    const ArrayMetadata &Meta = defineMetadata(Name, ElemInfo, LBs, UBs, TotalElements);
 
     Value *Ptr = DataPtr;
     if (MakeCopy) {