From dada0cb779fa0f342b3789a6c2c24522388d68db Mon Sep 17 00:00:00 2001
From: Andrew Morris <voltrevo@gmail.com>
Date: Sat, 1 Jul 2023 17:12:41 +1000
Subject: [PATCH] Extract constants later so that simplify has more information

---
 .../src/optimization/optimize.rs              |  6 +++++-
 valuescript_vm/src/bytecode_stack_frame.rs    | 20 +++++++++++++------
 valuescript_vm/src/cat_stack_frame.rs         |  2 +-
 3 files changed, 20 insertions(+), 8 deletions(-)

diff --git a/valuescript_compiler/src/optimization/optimize.rs b/valuescript_compiler/src/optimization/optimize.rs
index db604e8..c44d8b1 100644
--- a/valuescript_compiler/src/optimization/optimize.rs
+++ b/valuescript_compiler/src/optimization/optimize.rs
@@ -10,9 +10,13 @@ use super::simplify::simplify;
 
 pub fn optimize(module: &mut Module, pointer_allocator: &mut NameAllocator) {
   collapse_pointers_of_pointers(module);
-  extract_constants(module, pointer_allocator);
   shake_tree(module);
   simplify(module);
   remove_noops(module);
   remove_meta_lines(module);
+  extract_constants(module, pointer_allocator);
+
+  // After possibly repeated optimization, this ensures that the pointers are ordered correctly.
+  // TODO: Consider a dedicated step that's only about pointer ordering and not tree shaking.
+  shake_tree(module);
 }
diff --git a/valuescript_vm/src/bytecode_stack_frame.rs b/valuescript_vm/src/bytecode_stack_frame.rs
index 325ce8e..c555444 100644
--- a/valuescript_vm/src/bytecode_stack_frame.rs
+++ b/valuescript_vm/src/bytecode_stack_frame.rs
@@ -561,12 +561,20 @@ impl StackFrameTrait for BytecodeStackFrame {
       }
 
       Cat => {
-        assert!(
-          self.decoder.decode_type() == BytecodeType::Array,
-          "TODO: cat non-inline arrays"
-        );
-
-        let cat_frame = CatStackFrame::from_args(self.decoder.decode_vec_val(&mut self.registers));
+        let cat_frame = match self.decoder.peek_type() {
+          BytecodeType::Array => {
+            self.decoder.decode_type();
+            CatStackFrame::from_vec_val(self.decoder.decode_vec_val(&mut self.registers))
+          }
+          _ => match self.decoder.decode_val(&mut self.registers) {
+            Val::Array(array) => CatStackFrame::from_vec_val(array.elements.clone()),
+            _ => {
+              return Err(
+                "TODO: cat instruction on non-array (usually type error)".to_internal_error(),
+              )
+            }
+          },
+        };
 
         self.this_target = None;
         self.return_target = self.decoder.decode_register_index();
diff --git a/valuescript_vm/src/cat_stack_frame.rs b/valuescript_vm/src/cat_stack_frame.rs
index 32a7b7f..299b897 100644
--- a/valuescript_vm/src/cat_stack_frame.rs
+++ b/valuescript_vm/src/cat_stack_frame.rs
@@ -27,7 +27,7 @@ pub enum CatFrameState {
 }
 
 impl CatStackFrame {
-  pub fn from_args(args: Vec<Val>) -> Self {
+  pub fn from_vec_val(args: Vec<Val>) -> Self {
     Self {
       state: CatFrameState::ReadNext,
       iter_result: None,