From 7087c67d7951f77d11d2c0d6125a0e3c06182857 Mon Sep 17 00:00:00 2001
From: Valk Richard Li <48872266+ValKmjolnir@users.noreply.github.com>
Date: Mon, 8 Mar 2021 19:45:33 +0800
Subject: [PATCH] add constant table in vm

---
 main.cpp        |  2 +-
 nasal_codegen.h |  9 ++++++---
 nasal_vm.h      | 38 +++++++++++++++++---------------------
 test/bp.nas     |  2 +-
 4 files changed, 25 insertions(+), 26 deletions(-)

diff --git a/main.cpp b/main.cpp
index fea031b..36ad70a 100644
--- a/main.cpp
+++ b/main.cpp
@@ -153,7 +153,7 @@ int main()
 	system("cls");
 #endif
 	logo();
-	std::cout<<">> Nasal interpreter ver 5.0 .\n";
+	std::cout<<">> Nasal interpreter ver 6.0 .\n";
 	std::cout<<">> Code: https://github.com/ValKmjolnir/Nasal-Interpreter\n";
 	std::cout<<">> Info: http://wiki.flightgear.org/Nasal_scripting_language\n";
 	std::cout<<">> Input \"help\" to get help .\n";
diff --git a/nasal_codegen.h b/nasal_codegen.h
index de7c33f..16fe22c 100644
--- a/nasal_codegen.h
+++ b/nasal_codegen.h
@@ -103,7 +103,7 @@ struct
     {op_mcallv,      "mcallv"},
     {op_mcallh,      "mcallh"},
     {op_return,      "ret   "},
-    {-1,             NULL},
+    {-1,             NULL    },
 };
 
 struct opcode
@@ -231,10 +231,13 @@ void nasal_codegen::nil_gen()
 void nasal_codegen::number_gen(nasal_ast& ast)
 {
     double num=ast.get_num();
-    regist_number(num);
     if(num==1)      gen(op_pushone,0);
     else if(num==0) gen(op_pushzero,0);
-    else            gen(op_pushnum,number_table[num]);
+    else
+    {
+        regist_number(num);
+        gen(op_pushnum,number_table[num]);
+    }
     return;
 }
 
diff --git a/nasal_vm.h b/nasal_vm.h
index a2abfbc..8e7b985 100644
--- a/nasal_vm.h
+++ b/nasal_vm.h
@@ -8,6 +8,7 @@ private:
     nasal_val* zero_addr;          // reserved address of nasal_val,type vm_num, 0
     nasal_val* one_addr;           // reserved address of nasal_val,type vm_num, 1
     nasal_val* nil_addr;           // reserved address of nasal_val,type vm_nil
+    std::vector<nasal_val*> num_addrs; // reserved address for const vm_num
     bool main_loop_break_mark;     // when mark is false,break the main loop
     int ptr;                       // program counter
     int me_index;                  // this is the index of "me" in string_table
@@ -163,27 +164,27 @@ void nasal_vm::opr_load()
 }
 void nasal_vm::opr_pushnum()
 {
-    nasal_val* val_addr=gc.gc_alloc(vm_num);
-    val_addr->set_number(number_table[exec_code[ptr].index]);
+    nasal_val* val_addr=num_addrs[exec_code[ptr].index];
+    ++val_addr->ref_cnt;
     *(++val_stack_top)=val_addr;
     return;
 }
 void nasal_vm::opr_pushone()
 {
     *(++val_stack_top)=one_addr;
-    gc.add_reference(one_addr);
+    ++one_addr->ref_cnt;
     return;
 }
 void nasal_vm::opr_pushzero()
 {
     *(++val_stack_top)=zero_addr;
-    gc.add_reference(zero_addr);
+    ++zero_addr->ref_cnt;
     return;
 }
 void nasal_vm::opr_pushnil()
 {
     *(++val_stack_top)=nil_addr;
-    gc.add_reference(nil_addr);
+    ++nil_addr->ref_cnt;
     return;
 }
 void nasal_vm::opr_pushstr()
@@ -246,31 +247,20 @@ void nasal_vm::opr_unot()
     nasal_val* new_val_addr=NULL;
     int type=val_addr->get_type();
     if(type==vm_nil)
-    {
-        new_val_addr=gc.gc_alloc(vm_num);
-        new_val_addr->set_number(1);
-    }
+        new_val_addr=one_addr;
     else if(type==vm_num)
-    {
-        new_val_addr=gc.gc_alloc(vm_num);
-        new_val_addr->set_number(val_addr->get_number()==0);
-    }
+        new_val_addr=val_addr->get_number()?zero_addr:one_addr;
     else if(type==vm_str)
     {
         double number=trans_string_to_number(val_addr->get_string());
         if(std::isnan(number))
-        {
-            new_val_addr=gc.gc_alloc(vm_num);
-            new_val_addr->set_number(!val_addr->get_string().length());
-        }
+            new_val_addr=val_addr->get_string().length()?zero_addr:one_addr;
         else
-        {
-            new_val_addr=gc.gc_alloc(vm_num);
-            new_val_addr->set_number(number==0);
-        }
+            new_val_addr=number?zero_addr:one_addr;
     }
     else
         die("unot: incorrect value type");
+    ++new_val_addr->ref_cnt;
     *val_stack_top=new_val_addr;
     gc.del_reference(val_addr);
     return;
@@ -1094,6 +1084,12 @@ void nasal_vm::run(std::vector<std::string>& strs,std::vector<double>& nums,std:
     one_addr=gc.gc_alloc(vm_num);
     one_addr->set_number(1);
     nil_addr=gc.gc_alloc(vm_nil);
+    num_addrs.clear();
+    for(int i=0;i<number_table.size();++i)
+    {
+        num_addrs.push_back(gc.gc_alloc(vm_num));
+        num_addrs.back()->set_number(number_table[i]);
+    }
 
     builtin_use_string_table.clear();
     for(int i=0;i<string_table.size();++i)
diff --git a/test/bp.nas b/test/bp.nas
index 243da39..a19993f 100644
--- a/test/bp.nas
+++ b/test/bp.nas
@@ -127,7 +127,7 @@ var backward=func(x)
 var cnt=0;
 var show=0;
 var error=1e8;
-while(error>0.0005)
+while(error>0.001)
 {
     error=0;
     for(var i=0;i<4;i+=1)