From a110b93f5cd7bf624fcda839f12f5cc295a9eb4d Mon Sep 17 00:00:00 2001
From: Sky Johnson <skylearj@gmail.com>
Date: Thu, 17 Jul 2025 13:48:56 -0500
Subject: [PATCH] introduce bytecode caching, update state management to use it

---
 state/bytecode.go | 93 +++++++++++++++++++++++++++++++++++++++++++++++
 state/state.go    | 16 +++++---
 2 files changed, 103 insertions(+), 6 deletions(-)
 create mode 100644 state/bytecode.go

diff --git a/state/bytecode.go b/state/bytecode.go
new file mode 100644
index 0000000..325e955
--- /dev/null
+++ b/state/bytecode.go
@@ -0,0 +1,93 @@
+package state
+
+import (
+	"crypto/sha256"
+	"fmt"
+	"sync"
+
+	luajit "git.sharkk.net/Sky/LuaJIT-to-Go"
+)
+
+// BytecodeEntry holds compiled bytecode with metadata
+type BytecodeEntry struct {
+	Bytecode []byte
+	Name     string
+	Hash     [32]byte
+}
+
+// Global bytecode cache
+var (
+	bytecodeCache = struct {
+		sync.RWMutex
+		entries map[string]*BytecodeEntry
+	}{
+		entries: make(map[string]*BytecodeEntry),
+	}
+)
+
+// CompileAndCache compiles code to bytecode and stores it globally
+func CompileAndCache(state *luajit.State, code, name string) (*BytecodeEntry, error) {
+	hash := sha256.Sum256([]byte(code))
+	cacheKey := fmt.Sprintf("%x", hash)
+
+	// Check cache first
+	bytecodeCache.RLock()
+	if entry, exists := bytecodeCache.entries[cacheKey]; exists {
+		bytecodeCache.RUnlock()
+		return entry, nil
+	}
+	bytecodeCache.RUnlock()
+
+	// Compile bytecode
+	bytecode, err := state.CompileBytecode(code, name)
+	if err != nil {
+		return nil, err
+	}
+
+	// Store in cache
+	entry := &BytecodeEntry{
+		Bytecode: bytecode,
+		Name:     name,
+		Hash:     hash,
+	}
+
+	bytecodeCache.Lock()
+	bytecodeCache.entries[cacheKey] = entry
+	bytecodeCache.Unlock()
+
+	return entry, nil
+}
+
+// GetCached retrieves bytecode from cache by code hash
+func GetCached(code string) (*BytecodeEntry, bool) {
+	hash := sha256.Sum256([]byte(code))
+	cacheKey := fmt.Sprintf("%x", hash)
+
+	bytecodeCache.RLock()
+	defer bytecodeCache.RUnlock()
+
+	entry, exists := bytecodeCache.entries[cacheKey]
+	return entry, exists
+}
+
+// ClearCache removes all cached bytecode entries
+func ClearCache() {
+	bytecodeCache.Lock()
+	defer bytecodeCache.Unlock()
+
+	bytecodeCache.entries = make(map[string]*BytecodeEntry)
+}
+
+// CacheStats returns cache statistics
+func CacheStats() (int, int64) {
+	bytecodeCache.RLock()
+	defer bytecodeCache.RUnlock()
+
+	count := len(bytecodeCache.entries)
+	var totalSize int64
+	for _, entry := range bytecodeCache.entries {
+		totalSize += int64(len(entry.Bytecode))
+	}
+
+	return count, totalSize
+}
diff --git a/state/state.go b/state/state.go
index 3b237a2..fd0b4cd 100644
--- a/state/state.go
+++ b/state/state.go
@@ -159,15 +159,14 @@ func (s *State) ExecuteFile(scriptPath string) error {
 	return s.ExecuteString(string(scriptContent), scriptPath)
 }
 
-// ExecuteString compiles and runs Lua code
+// ExecuteString compiles and runs Lua code with bytecode caching
 func (s *State) ExecuteString(code, name string) error {
-	// Use bytecode compilation for better performance
-	bytecode, err := s.CompileBytecode(code, name)
+	entry, err := CompileAndCache(s.State, code, name)
 	if err != nil {
 		return fmt.Errorf("compilation error in '%s': %w", name, err)
 	}
 
-	if err := s.LoadAndRunBytecode(bytecode, name); err != nil {
+	if err := s.LoadAndRunBytecode(entry.Bytecode, name); err != nil {
 		return fmt.Errorf("execution error in '%s': %w", name, err)
 	}
 
@@ -188,16 +187,21 @@ func (s *State) ExecuteFileWithResults(scriptPath string) ([]any, error) {
 	return s.ExecuteStringWithResults(string(scriptContent), scriptPath)
 }
 
-// ExecuteStringWithResults executes code and returns all results
+// ExecuteStringWithResults executes code and returns all results with bytecode caching
 func (s *State) ExecuteStringWithResults(code, name string) ([]any, error) {
 	baseTop := s.GetTop()
 	defer s.SetTop(baseTop)
 
-	nresults, err := s.Execute(code)
+	entry, err := CompileAndCache(s.State, code, name)
 	if err != nil {
+		return nil, fmt.Errorf("compilation error in '%s': %w", name, err)
+	}
+
+	if err := s.LoadAndRunBytecodeWithResults(entry.Bytecode, name, -1); err != nil {
 		return nil, fmt.Errorf("execution error in '%s': %w", name, err)
 	}
 
+	nresults := s.GetTop() - baseTop
 	if nresults == 0 {
 		return nil, nil
 	}