.

TODO.md

@@ -1,65 +1,52 @@
-## Bytecode
+## C
 
-- [x] Byte array
-  - Auto-expand
-  - Add/retrive byte/int/float/string
-  - Should not be larger than the byte array itself
-- [x] Bytecode
-  - Add/retrive all types of data
-  - Keeps no memory except for caching
-  - [x] Refactor bytecode code
+Decisions:
+ - How to handle errors
+ - How values and heap values will be represented
+ - Transparency and log levels
 
-Improvements:
-- [x] Fixed int type (based on opcode)
-- [x] Constant type (only floats and strings for now)
-
-After some additional development:
-- [ ] Bytecode debugging info
-
-
-## VM
-
-- [x] VM
-  - [x] Code
-    - [x] Simple bytecode loader
-      - [x] Output bytecode format
-  - [x] Value object
-  - [x] Stack object
-  - [x] External interface
-  - [x] Code execution (except functions)
-  - [x] Functions
-  - [x] Print stack
-- [x] Assembler
-- [ ] VM execution
-  - [x] Stack operations (nil, integer, float, string, function)
-    - [x] Integer
-    - [x] Float
-    - [x] String
-  - [x] Expressions
-    - [x] Integer
-    - [x] Float
-    - [x] String
-  - [ ] Local/global variables
+- [ ] Makefile
+- [ ] Value and stack value
+- [ ] Stack
+  - [ ] Test application (C++?)
+- [ ] Heap
+- [ ] VM
+  - [ ] (Lua interface) call assembler
+  - [ ] (Lua) generate bytecode
+    - [ ] Labels
+  - [ ] Code
+    - [ ] Interpret bytecode (fast)
+  - [ ] Execution loop (fast)
+- [ ] VM operations
+  - [ ] Expressions
+  - [ ] Local variables
   - [ ] Functions
-  - [ ] Constants
-  - [ ] Other operations
-  - [ ] Arrays
-    - [ ] Iteration
-    - [ ] Expressions
-  - [ ] Tables
-    - [ ] Iteration
-    - [ ] Metatables
-    - [ ] Expressions
+    - [ ] With parameters
   - [ ] Control flow
-  - [ ] Compilation
+    - [ ] Recursion
+  - [ ] Strings
+    - [ ] From constants
+    - [ ] Garbage collection
+  - [ ] Arrays
+    - [ ] Garbage collection
+  - [ ] Tables
+    - [ ] Garbage collection
+    - [ ] Metatables
+    - [ ] Iteration
+  - [ ] Floats (real)
+  - [ ] Globals (?)
   - [ ] Error handling
-- [ ] C++ API
-  - [ ] Run native code on VM
-  - [ ] Run tyche code from C++
-  - [ ] C API
+    - [ ] Stack trace in case of errors
+  - [ ] Closure/upvalues
+  - [ ] Rest of opcodes
+- [ ] Prepare for release
+  - [ ] Documentation and webpage
 
-After some additional development:
-- [ ] Bytecode loader
-  - Combine multiple chunks
-  - Resolve function ids, constant ids, etc
-- [ ] Upvalues
+## Future versions
+
+- [ ] Debugging information
+- [ ] Debugger
+- [ ] Dynamic language
+- [ ] Support tools
+  - [ ] Editor syntax file, etc
+- [ ] Static language

doc/OPCODES

@@ -22,12 +22,13 @@ Stack operations:
    a0  c0 e0    pushi [int]          Push int
    a1  c1 e1    pushc [index]        Push constant
    a2  c2 e2    pushf [function]     Push function id
-00              pushz                Push zero (or false)
-01              pusht                Push true
-02              newa                 Push (create) empty array
-03              newt                 Push (create) empty table
-04              pop
-05              dup
+00              pushn                Push nil
+01              pushz                Push zero (or false)
+02              pusht                Push true
+03              newa                 Push (create) empty array
+04              newt                 Push (create) empty table
+05              pop
+06              dup
 
 Local variables:
    a3  c3 e3    pushv [int]          Push n nil values into the stack (used to init local vars)
@@ -44,12 +45,12 @@ Function operations:
 Table and array operations:
 16              getkv                Get table's value based on key (pull 1 value, push 1 value)
 17              setkv                Set table's key and value (pull 2 values from stack)
-18              geta                 Get array's position value
-19              seta                 Set array's position value (pull 2 values from stack)
-1a              appnd                Add value to the end of array
-1b              next                 Push the next pair into the stack (for loops)
-1c              smt                  Set value metatable
-1d              mt                   Get value metatable
+  a8  c8 e8     geti                 Get array's position value
+  a9  c9 e9     seti                 Set array's position value
+18              appnd                Add value to the end of array
+19              next                 Push the next pair into the stack (for loops)
+1a              smt                  Set value metatable
+1b              mt                   Get value metatable
 
 Logical/arithmetic:
 20              sum                  Sum top 2 values in stack
@@ -57,24 +58,24 @@ Logical/arithmetic:
 22              mul                  Multiply top 2 values in stack
 23              div                  Float division
 24              idiv                 Integer division
-25              eq                   Equality
-26              neq                  Inequality
-27              lt                   Less than
-28              lte                  Less than or equals
-29              gt                   Greater than
-2a              gte                  Greater than or equals
-2b              and                  Bitwise AND
-2c              or                   Bitwise OR
-2d              xor                  Bitwise XOR
-2e              pow                  Power
-2f              shl                  Shift left
-30              shr                  Shift right
-31              mod                  Modulo
+25              mod                  Modulo
+26              eq                   Equality
+27              neq                  Inequality
+28              lt                   Less than
+29              lte                  Less than or equals
+2a              gt                   Greater than
+2b              gte                  Greater than or equals
+2c              and                  Bitwise AND
+2d              or                   Bitwise OR
+2e              xor                  Bitwise XOR
+2f              pow                  Power
+30              shl                  Shift left
+31              shr                  Shift right
 
 Other value operations:
 40              len                  Get table, array or string size
 41              type                 Get type from value at the top of the stack
-   b0           cast [type]          Cast type to another type
+   aa           cast [type]          Cast type to another type
 42              ver                  Return VM version
 
 External code:
@@ -82,12 +83,14 @@ External code:
 49              asmbl                Assemble code to bytecode format
 4a              load                 Load bytecode as function (will place function on stack)
 
-Control flow:
-   a8 c8 e8     bz [pc]              Branch if zero
-   a9 c9 e9     bnz [pc]             Branch if not zero
-   aa ca ea     jmp [pc]             Unconditional jump
+Control flow (the destination is always a 16-bit field):
+      ca        bz [pc]              Branch if zero
+      cb        bnz [pc]             Branch if not zero
+      cc        jmp [pc]             Unconditional jump
 * Jumps can only happen within the same function.
 
+Memory management:
+4b              gc                   Call garbage collector
 
 Error handling: (0xa0~0xaf)
    ???