refactor(memory)!: move allocation functions into memory.cps

Route keyword NEW and DELETE through the same library runtime and retain
allocation tracking, runtime diagnostics and exception behavior.

BREAKING CHANGE: -no-std programs using NEW or DELETE must explicitly import memory.cps.

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

9 files changed, 36 insertions, 209 deletions

diff --git a/lib/CodeGen/Builtins.h b/lib/CodeGen/Builtins.h
index 84ba765..66ac9e4 100644
--- a/lib/CodeGen/Builtins.h
+++ b/lib/CodeGen/Builtins.h
@@ -15,9 +15,6 @@ struct BuiltinInfo {
 
 inline constexpr BuiltinInfo Builtins[] = {
     {"EOF",        1, "BOOLEAN"},
-    {"MALLOC",     1, "C_TYPE(\"void*\")"},
-    {"REALLOC",    2, "C_TYPE(\"void*\")"},
-    {"FREE",       1, "C_TYPE(\"void*\")"},
     {"INT",        1, "INTEGER"},
 };
 
diff --git a/lib/CodeGen/CallGen.cc b/lib/CodeGen/CallGen.cc
index 30f0d61..f3a6a9d 100644
--- a/lib/CodeGen/CallGen.cc
+++ b/lib/CodeGen/CallGen.cc
@@ -2,7 +2,6 @@
 #include "cps/CodeGen.h"
 #include "cps/ArrayHandler.h"
 #include "cps/FileHandler.h"
-#include "cps/MemoryHandler.h"
 #include "cps/ExceptionHandler.h"
 #include "Builtins.h"
 #include "TemplateClone.h"
diff --git a/lib/CodeGen/CodeGen.cc b/lib/CodeGen/CodeGen.cc
index 64ed7c4..49b470c 100644
--- a/lib/CodeGen/CodeGen.cc
+++ b/lib/CodeGen/CodeGen.cc
@@ -2,7 +2,6 @@
 #include "cps/CodeGen.h"
 #include "cps/ArrayHandler.h"
 #include "cps/FileHandler.h"
-#include "cps/MemoryHandler.h"
 #include "cps/ExceptionHandler.h"
 #include "Builtins.h"
 #include "TemplateClone.h"
@@ -61,9 +60,6 @@ CodeGen::CodeGen() {
     Files = std::make_unique<FileHandler>(*TheContext, *Builder, *TheModule, *RuntimeChecker,
                                          *Exceptions);
 
-    Memory = std::make_unique<MemoryHandler>(*TheContext, *Builder, *TheModule, *Types,
-                                             *RuntimeChecker, *Exceptions);
-
     // Array parameters are bound into ArrayHandler through this inversion so
     // FunctionGen never sees the array subsystem.
     FuncGen->setArrayParamBinder(
diff --git a/lib/CodeGen/ConstructorGen.cc b/lib/CodeGen/ConstructorGen.cc
index f598494..b029385 100644
--- a/lib/CodeGen/ConstructorGen.cc
+++ b/lib/CodeGen/ConstructorGen.cc
@@ -1,5 +1,4 @@
 #include "cps/CodeGen.h"
-#include "cps/MemoryHandler.h"
 #include "cps/ExceptionHandler.h"
 #include "cps/TypeAST.h"
 #include <climits>
@@ -165,7 +164,8 @@ void CodeGen::emitAssignment(const LValueInfo &Target, ExprAST *Expr, const Symb
         // a non-null object address (MALLOC(0) deliberately returns null).
         Size = Builder->CreateSelect(Builder->CreateICmpEQ(Size, ConstantInt::get(Size->getType(), 0)),
                                       ConstantInt::get(Size->getType(), 1), Size);
-        Value *Object = Memory->emitAllocate(Size, New->getLine());
+        Value *Object = emitMemoryCall("_memory_impl_malloc", Size, New->getLine());
+        if (!Object) return;
         Builder->CreateStore(Types->getZeroValue(Class->Name), Object);
         if (!emitConstruct(Class->Name, Object, New->getArgs(), New->getLine())) return;
         if (Symbol && Symbol->IsReference) {
diff --git a/lib/CodeGen/ExpressionGen.cc b/lib/CodeGen/ExpressionGen.cc
index 18c934d..9f68a82 100644
--- a/lib/CodeGen/ExpressionGen.cc
+++ b/lib/CodeGen/ExpressionGen.cc
@@ -1,13 +1,10 @@
 #include "cps/CodeGen.h"
 #include "cps/ArrayHandler.h"
 #include "cps/FileHandler.h"
-#include "cps/MemoryHandler.h"
 #include "cps/Lexer.h"
 #include "cps/TypeAST.h"
 #include "cps/Operator.h"
 #include "Builtins.h"
-#include <climits>
-#include <cstddef>
 
 using namespace llvm;
 using namespace cps;
@@ -300,23 +297,6 @@ Value *CodeGen::emitCall(const std::string &Callee,
             return nullptr;
         }
     }
-    if (Name == "MALLOC") {
-        Value *Size = emitAllocationSize(ArgExprs[0].get());
-        if (!Size) return nullptr;
-        return Memory->emitAllocate(Size, Line);
-    }
-    if (Name == "REALLOC") {
-        Value *Address = emitCoercedExpr(ArgExprs[0].get(), resolveType("C_TYPE(\"void*\")"));
-        if (!Address) return nullptr;
-        Value *Size = emitAllocationSize(ArgExprs[1].get());
-        if (!Size) return nullptr;
-        return Memory->emitResize(Address, Size, Line);
-    }
-    if (Name == "FREE") {
-        Value *Address = emitCoercedExpr(ArgExprs[0].get(), resolveType("C_TYPE(\"void*\")"));
-        if (!Address) return nullptr;
-        return Memory->emitRelease(Address, Line);
-    }
     if (Name == "INT") return emitIntBuiltin(ArgExprs[0].get(), Line);
     if (Name == "EOF") {
         Value *FileName = emitFileNameOperand(ArgExprs[0].get(), "EOF");
@@ -354,19 +334,3 @@ Value *CodeGen::emitIntBuiltin(ExprAST *Arg, int Line) {
     RuntimeChecker->emitCheck(OutOfRange, Msg, {RuntimeChecker->lineValue(Line)});
     return Builder->CreateFPToSI(V, Type::getInt64Ty(*TheContext), "int_value");
 }
-
-Value *CodeGen::emitAllocationSize(ExprAST *Expr) {
-    SaveAndRestore<int> Location(DiagnosticLine, Expr->getLine() ? Expr->getLine() : DiagnosticLine);
-    const TypeInfo *Info = getExprTypeInfo(Expr);
-    if (isWholeArrayVar(Expr) || !Info ||
-        !(Info->Kind == TypeKind::Integer ||
-          (Info->Kind == TypeKind::CScalar && Info->isIntegral()))) {
-        reportError("Allocation size must be INTEGER or a C integer");
-        return nullptr;
-    }
-    Value *Size = emitExpr(Expr);
-    if (!Size) return nullptr;
-    auto *SizeTy = Type::getIntNTy(*TheContext, sizeof(std::size_t) * CHAR_BIT);
-    return Builder->CreateIntCast(Size, SizeTy,
-                                  Info->Kind == TypeKind::Integer || Info->CSigned, "allocation_size");
-}
diff --git a/lib/CodeGen/FunctionGen.cc b/lib/CodeGen/FunctionGen.cc
index 2e927f9..c162b46 100644
--- a/lib/CodeGen/FunctionGen.cc
+++ b/lib/CodeGen/FunctionGen.cc
@@ -158,7 +158,8 @@ bool FunctionGen::validatePrototype(PrototypeAST *Proto) {
         return false;
     }
     if (Proto->getOwnerClass().empty()) {
-        if (!Proto->isExternal() && isReservedRuntimeName(Proto->getName())) {
+        // OVERLOAD symbols carry a signature and cannot replace libc symbols.
+        if (!Proto->isExternal() && !Proto->isOverload() && isReservedRuntimeName(Proto->getName())) {
             reportError("'%s' is a reserved runtime symbol and cannot be a FUNCTION/PROCEDURE name",
                     Proto->getName().c_str());
             return false;
diff --git a/lib/CodeGen/MemoryGen.cc b/lib/CodeGen/MemoryGen.cc
new file mode 100644
index 0000000..453f137
--- /dev/null
+++ b/lib/CodeGen/MemoryGen.cc
@@ -0,0 +1,30 @@
+#include "cps/CodeGen.h"
+
+using namespace llvm;
+using namespace cps;
+
+// Keyword NEW/DELETE use the same visible C helpers as memory.cps. Ordinary
+// MALLOC/REALLOC/FREE calls are resolved entirely through the library.
+Value *CodeGen::emitMemoryCall(const char *Name, Value *Argument, int Line) {
+    SaveAndRestore<int> Location(DiagnosticLine, Line);
+    auto Declarations = FuncGen->getOverloads(Name);
+    if (Declarations.empty()) {
+        reportError("NEW/DELETE requires memory.cps; include the memory library");
+        return nullptr;
+    }
+    const FuncSig &Sig = *Declarations.front();
+    bool Allocate = sameIdentifier(Name, "_memory_impl_malloc");
+    bool Validate = sameIdentifier(Name, "_memory_impl_validate");
+    const TypeInfo *Parameter = resolveType(Allocate ? "C_TYPE(\"unsigned long long\")"
+                                                    : "C_TYPE(\"void*\")");
+    const TypeInfo *Result = resolveType(Validate ? "VOID" : "C_TYPE(\"void*\")");
+    if (!Sig.IsExternal || Sig.IsVariadic || Sig.Params.size() != 1 ||
+        Sig.Params[0].IsArray || Sig.Params[0].IsByRef ||
+        !Types->sameType(Sig.Params[0].TypeName, Parameter->Name) ||
+        !Types->sameType(Sig.ReturnTypeName, Result->Name)) {
+        reportError("Invalid memory runtime declaration for %s", Name);
+        return nullptr;
+    }
+    if (Allocate) Argument = Builder->CreateIntCast(Argument, Parameter->LLVMType, false);
+    return FuncGen->emitCall(Sig, {Argument});
+}
diff --git a/lib/CodeGen/MemoryHandler.cc b/lib/CodeGen/MemoryHandler.cc
deleted file mode 100644
index 7cb62b3..0000000
--- a/lib/CodeGen/MemoryHandler.cc
+++ /dev/null
@@ -1,159 +0,0 @@
-#include "cps/MemoryHandler.h"
-#include "cps/ExceptionHandler.h"
-#include "cps/RuntimeCheck.h"
-#include "cps/TypeSystem.h"
-#include <climits>
-#include <cstddef>
-
-using namespace llvm;
-using namespace cps;
-
-Function *MemoryHandler::createHelper(const char *Name, ArrayRef<Type *> Args) {
-    auto *F = Function::Create(FunctionType::get(PointerType::getUnqual(Context), Args, false),
-                               Function::InternalLinkage, Name, Module);
-    Exceptions.prepareFunction(F);
-    Builder.SetInsertPoint(BasicBlock::Create(Context, "entry", F));
-    return F;
-}
-
-void MemoryHandler::ensureRuntime() {
-    if (AllocateFn) return;
-    IRBuilderBase::InsertPointGuard Guard(Builder);
-    auto *Ptr = PointerType::getUnqual(Context);
-    auto *I32 = Type::getInt32Ty(Context);
-    SizeTy = Type::getIntNTy(Context, sizeof(std::size_t) * CHAR_BIT);
-    NodeTy = StructType::create(Context, {Ptr, Ptr}, "__cps_memory_node");
-    Head = new GlobalVariable(Module, Ptr, false, GlobalValue::InternalLinkage,
-                              ConstantPointerNull::get(Ptr), "__cps_memory_head");
-    Malloc = Module.getOrInsertFunction("malloc", FunctionType::get(Ptr, {SizeTy}, false));
-    Free = Module.getOrInsertFunction("free", FunctionType::get(Type::getVoidTy(Context), {Ptr}, false));
-    Realloc = Module.getOrInsertFunction("realloc", FunctionType::get(Ptr, {Ptr, SizeTy}, false));
-    AllocationError = Builder.CreateGlobalString("[Fatal] line %d: Memory allocation failed\n",
-                                                  "err_allocation", 0, &Module);
-    TrackingError = Builder.CreateGlobalString("[Fatal] line %d: Allocation tracking failed\n",
-                                                "err_tracking", 0, &Module);
-    InvalidAddress = Builder.CreateGlobalString("[Fatal] line %d: Invalid memory address (not an active allocation)\n",
-                                                 "err_memory_address", 0, &Module);
-    FindFn = createHelper("__cps_memory_find", {Ptr, I32});
-    buildFind();
-    AllocateFn = createHelper("__cps_memory_allocate", {SizeTy, I32});
-    buildAllocate();
-    ReleaseFn = createHelper("__cps_memory_release", {Ptr, I32});
-    buildRelease();
-    ResizeFn = createHelper("__cps_memory_resize", {Ptr, SizeTy, I32});
-    buildResize();
-}
-
-// Return the address of the list link that owns the matching node. This also
-// lets release unlink the head or an interior node through the same operation.
-void MemoryHandler::buildFind() {
-    auto *Ptr = PointerType::getUnqual(Context);
-    Value *Address = FindFn->getArg(0), *Line = FindFn->getArg(1);
-    auto *Entry = Builder.GetInsertBlock();
-    auto *Loop = BasicBlock::Create(Context, "search", FindFn);
-    auto *Found = BasicBlock::Create(Context, "found", FindFn);
-    Builder.CreateBr(Loop);
-    Builder.SetInsertPoint(Loop);
-    auto *Link = Builder.CreatePHI(Ptr, 2, "link");
-    Link->addIncoming(Head, Entry);
-    Value *Node = Builder.CreateLoad(Ptr, Link, "node");
-    Checker.emitCheck(Builder.CreateIsNull(Node), InvalidAddress, {Line});
-    Value *Stored = Builder.CreateLoad(Ptr, Builder.CreateStructGEP(NodeTy, Node, 0));
-    Value *NextLink = Builder.CreateStructGEP(NodeTy, Node, 1);
-    Link->addIncoming(NextLink, Builder.GetInsertBlock());
-    Builder.CreateCondBr(Builder.CreateICmpEQ(Stored, Address), Found, Loop);
-    Builder.SetInsertPoint(Found);
-    Builder.CreateRet(Link);
-}
-
-void MemoryHandler::buildAllocate() {
-    auto *Ptr = PointerType::getUnqual(Context);
-    Value *Size = AllocateFn->getArg(0), *Line = AllocateFn->getArg(1);
-    auto *Zero = BasicBlock::Create(Context, "zero_size", AllocateFn);
-    auto *Allocate = BasicBlock::Create(Context, "allocate", AllocateFn);
-    Builder.CreateCondBr(Builder.CreateICmpEQ(Size, ConstantInt::get(SizeTy, 0)), Zero, Allocate);
-    Builder.SetInsertPoint(Zero);
-    Builder.CreateRet(ConstantPointerNull::get(Ptr));
-    Builder.SetInsertPoint(Allocate);
-    Value *NodeSize = Builder.CreateIntCast(Types.getSizeOfConstant(NodeTy), SizeTy, false);
-    Value *Node = Builder.CreateCall(Malloc, {NodeSize}, "new_node");
-    Checker.emitCheck(Builder.CreateIsNull(Node), TrackingError, {Line});
-    Value *Address = Builder.CreateCall(Malloc, {Size}, "allocation");
-    Value *Failed = Builder.CreateIsNull(Address);
-    auto *Cleanup = BasicBlock::Create(Context, "cleanup_node", AllocateFn);
-    auto *Checked = BasicBlock::Create(Context, "check_allocation", AllocateFn);
-    Builder.CreateCondBr(Failed, Cleanup, Checked);
-    Builder.SetInsertPoint(Cleanup);
-    Builder.CreateCall(Free, {Node});
-    Builder.CreateBr(Checked);
-    Builder.SetInsertPoint(Checked);
-    Checker.emitCheck(Failed, AllocationError, {Line});
-    Builder.CreateStore(Address, Builder.CreateStructGEP(NodeTy, Node, 0));
-    Builder.CreateStore(Builder.CreateLoad(Ptr, Head), Builder.CreateStructGEP(NodeTy, Node, 1));
-    Builder.CreateStore(Node, Head);
-    Builder.CreateRet(Address);
-}
-
-void MemoryHandler::buildRelease() {
-    auto *Ptr = PointerType::getUnqual(Context);
-    Value *Address = ReleaseFn->getArg(0), *Line = ReleaseFn->getArg(1);
-    auto *Done = BasicBlock::Create(Context, "done", ReleaseFn);
-    auto *Release = BasicBlock::Create(Context, "release", ReleaseFn);
-    Builder.CreateCondBr(Builder.CreateIsNull(Address), Done, Release);
-    Builder.SetInsertPoint(Release);
-    Value *Link = Exceptions.emitCall(FindFn, {Address, Line}, "link");
-    Value *Node = Builder.CreateLoad(Ptr, Link);
-    Value *Next = Builder.CreateLoad(Ptr, Builder.CreateStructGEP(NodeTy, Node, 1));
-    Builder.CreateStore(Next, Link);
-    Builder.CreateCall(Free, {Address});
-    Builder.CreateCall(Free, {Node});
-    Builder.CreateBr(Done);
-    Builder.SetInsertPoint(Done);
-    Builder.CreateRet(Address);
-}
-
-Value *MemoryHandler::emitAllocate(Value *Size, int Line) {
-    ensureRuntime();
-    return Exceptions.emitCall(AllocateFn, {Size, Checker.lineValue(Line)}, "allocated");
-}
-
-Value *MemoryHandler::emitRelease(Value *Address, int Line) {
-    ensureRuntime();
-    return Exceptions.emitCall(ReleaseFn, {Address, Checker.lineValue(Line)}, "released");
-}
-
-void MemoryHandler::buildResize() {
-    auto *Ptr = PointerType::getUnqual(Context);
-    Value *Address = ResizeFn->getArg(0), *Size = ResizeFn->getArg(1), *Line = ResizeFn->getArg(2);
-    auto *Allocate = BasicBlock::Create(Context, "allocate", ResizeFn);
-    auto *Validate = BasicBlock::Create(Context, "validate", ResizeFn);
-    auto *Release = BasicBlock::Create(Context, "release", ResizeFn);
-    auto *Resize = BasicBlock::Create(Context, "resize", ResizeFn);
-    Builder.CreateCondBr(Builder.CreateIsNull(Address), Allocate, Validate);
-    Builder.SetInsertPoint(Allocate);
-    Builder.CreateRet(Exceptions.emitCall(AllocateFn, {Size, Line}, "allocation"));
-    Builder.SetInsertPoint(Validate);
-    Value *Link = Exceptions.emitCall(FindFn, {Address, Line}, "link");
-    Value *Node = Builder.CreateLoad(Ptr, Link);
-    Builder.CreateCondBr(Builder.CreateICmpEQ(Size, ConstantInt::get(SizeTy, 0)), Release, Resize);
-    Builder.SetInsertPoint(Release);
-    Exceptions.emitCall(ReleaseFn, {Address, Line});
-    Builder.CreateRet(ConstantPointerNull::get(Ptr));
-    Builder.SetInsertPoint(Resize);
-    Value *NewAddress = Builder.CreateCall(Realloc, {Address, Size}, "resized");
-    // libc preserves the original block on nonzero-size failure. Leave the
-    // tracking entry untouched until the check has succeeded as well.
-    Checker.emitCheck(Builder.CreateIsNull(NewAddress), AllocationError, {Line});
-    Builder.CreateStore(NewAddress, Builder.CreateStructGEP(NodeTy, Node, 0));
-    Builder.CreateRet(NewAddress);
-}
-
-Value *MemoryHandler::emitResize(Value *Address, Value *Size, int Line) {
-    ensureRuntime();
-    return Exceptions.emitCall(ResizeFn, {Address, Size, Checker.lineValue(Line)}, "resized");
-}
-
-void MemoryHandler::emitValidate(Value *Address, int Line) {
-    ensureRuntime();
-    Exceptions.emitCall(FindFn, {Address, Checker.lineValue(Line)});
-}
diff --git a/lib/CodeGen/StatementGen.cc b/lib/CodeGen/StatementGen.cc
index c161049..3cacfe9 100644
--- a/lib/CodeGen/StatementGen.cc
+++ b/lib/CodeGen/StatementGen.cc
@@ -2,7 +2,6 @@
 #include "cps/ArrayHandler.h"
 #include "cps/FileAST.h"
 #include "cps/FileHandler.h"
-#include "cps/MemoryHandler.h"
 #include "cps/ExceptionHandler.h"
 #include "cps/TypeAST.h"
 #include "cps/TemplateAST.h"
@@ -54,9 +53,9 @@ void CodeGen::emitStmtImpl(StmtAST *Stmt) {
             reportError("DELETE requires a class object");
             return;
         }
-        Memory->emitValidate(Object.Addr, Stmt->getLine());
+        if (!emitMemoryCall("_memory_impl_validate", Object.Addr, Stmt->getLine())) return;
         if (emitDestroy(Object.TypeName, Object.Addr, Stmt->getLine()))
-            Memory->emitRelease(Object.Addr, Stmt->getLine());
+            emitMemoryCall("_memory_impl_free", Object.Addr, Stmt->getLine());
         return;
     }
     if (auto *Try = dynamic_cast<TryStmtAST*>(Stmt)) {