Allow referencing code in imported file (right now for function calls, allow calling a function in another file)

2 files changed, 63 insertions, 52 deletions

diff --git a/doc/Documentation.md b/doc/Documentation.md
index adb0bef..ca579a2 100644
--- a/doc/Documentation.md
+++ b/doc/Documentation.md
@@ -16,11 +16,14 @@ Instructions can be in 7 different formats:
 6.2 Opcode(u8) + register(i8) + intermediate(u16)\
 6.3 Opcode(u8) + register(i8) + data(u16)\
 6.4 Opcode(u8) + flags(u8) + num_local_var_reg(u16)
-7. 5 bytes: Opcode(u8) + index(u16) + num_args(u8) + register(i8)
+7. 5 bytes: Opcode(u8) + index(u8) + index(u16) + num_args(u8)
 ## Registers
 Registers have a range of 128. Local variables start from register 0 and increment while parameters start from -1
 and decrement. Registers have the scope of functions and reset after instructions reach a new function (AMAL_OP_FUNC_START).
 
+If import index for call and calle is 0, then that means the function resides in the same file the function call
+is being called from. Which means that import index 1 is actually import index 0 into the import list.
+
 # Compiler flow
 (Tokenize&parse -> Resolve AST -> Generate SSA -> Generate bytecode) -> Generate program\
 Each step except the last is done using multiple threads in parallel and the output of each step is used
@@ -29,7 +32,9 @@ and writing it to a file, which is an IO bottlenecked operation and it won't ben
 and may even lose performance because of it.
 
 # Bytecode
-The layout of the full bytecode is: Header (Intermediates Strings Functions External_Functions Exported_Functions Instructions)*
+The layout of the full bytecode is: Header (X Intermediates X Strings X Functions X External_Functions X Exported_Functions X Imports X Instructions)*\
+Where the X is a magic number to make it easier to find errors while decoding the bytecode.\
+The value of the magic number is @AMAL_BYTECODE_SECTION_MAGIC_NUMBER
 
 # Bytecode header
 ## Header layout
@@ -44,10 +49,10 @@ The versions in the header only changes for every release, not every change.
 
 # Bytecode intermediates
 ## Intermediates layout
-|Type        |Field             |Description                                                                    |
-|------------|------------------|-------------------------------------------------------------------------------|
-|u32         |Intermediates size|The size of the intermediates section, in bytes.                               |
-|Intermediate|Intermediate data |Multiple intermediates, where the total size is defined by @Intermediates size.|
+|Type          |Field             |Description                                                                    |
+|--------------|------------------|-------------------------------------------------------------------------------|
+|u32           |Intermediates size|The size of all intermediates, in bytes.                                       |
+|Intermediate[]|Intermediate data |Multiple intermediates, where the total size is defined by @Intermediates size.|
 
 ## Intermediate
 |Type|Field|Description                                         |
@@ -57,11 +62,11 @@ The versions in the header only changes for every release, not every change.
 
 # Bytecode strings
 ## Strings layout
-|Type  |Field            |Description                                                       |
-|------|-----------------|------------------------------------------------------------------|
-|u16   |Number of strings|The number of strings.                                            |
-|u32   |Strings size     |The size of the strings section, in bytes.                        |
-|String|Strings data     |Multiple strings, where the total size is defined by @Strings size|
+|Type    |Field            |Description                                                       |
+|--------|-----------------|------------------------------------------------------------------|
+|u16     |Number of strings|The number of strings.                                            |
+|u32     |Strings size     |The size of all strings, in bytes.                                |
+|String[]|Strings data     |Multiple strings, where the total size is defined by @Strings size|
 
 ## String
 |Type|Field|Description                                                                            |
@@ -70,33 +75,46 @@ The versions in the header only changes for every release, not every change.
 |u8* |Data|The data of the string, where the size is defined by @Size. Strings are null-terminated.|
 
 # Bytecode functions
-## Internal functions layout
-|Type|Field              |Description                      |
-|----|-------------------|---------------------------------|
-|u16 |Number of functions|The number of internal functions.|
+## Functions layout
+|Type      |Field     |Description                                                                           |
+|----------|----------|--------------------------------------------------------------------------------------|
+|u16       |num_funcs |The number of non-extern functions.                                                   |
+|u32       |funcs_size|The size of all functions, in bytes.                                                  |
+|Function[]|Functions |Multiple non-extern functions, where the number of functions is defined by @num_funcs.|
+
+## Function
+|Type|Field                    |Description                                                                                                             |
+|----|-------------------------|------------------------------------------------------------------------------------------------------------------------|
+|u32 |func_offset              |The offset in the program code (machine code) where the function starts. Is always 0 until the program has been started.|
+|u8  |num_params               |The number of parameters.                                                                                               |
+|u32 |params_num_pointers      |The number of pointers in the parameters.                                                                               |
+|u32 |params_fixed_size        |The size of all non-pointer type parameters, in bytes.                                                                  |
+|u8  |num_return_types         |The number of return values.                                                                                            |
+|u32 |return_types_num_pointers|The number of pointers in the return types.                                                                             |
+|u32 |return_types_fixed_size  |The size of all non-pointer type return types, in bytes.                                                                |
 
 # Bytecode external functions
 ## External functions layout
-|Type             |Field             |Description                                                                              |
-|-----------------|------------------|-----------------------------------------------------------------------------------------|
-|u16              |num_extern_func   |The number of external functions.                                                        |
-|u32              |extern_funcs_size |The size of the external functions section, in bytes.                                    |
-|External function|External functions|Multiple external functions, where the number of functions is defined by @num_extern_func|
+|Type               |Field             |Description                                                                              |
+|-------------------|------------------|-----------------------------------------------------------------------------------------|
+|u16                |num_extern_func   |The number of external functions.                                                        |
+|u32                |extern_funcs_size |The size of all external functions, in bytes.                                            |
+|External function[]|External functions|Multiple external functions, where the number of functions is defined by @num_extern_func|
 
 ## External function
-|Type|Field   |Description                                                                                          |
-|----|--------|-----------------------------------------------------------------------------------------------------|
-|u8  |num_args|The number of arguments the functions has.                                                           |
-|u8  |name_len|The length of the external function name, in bytes. Excluding the null-terminate character.          |
-|u8* |name    |The name of the external function, where the size is defined by @name_len. Names are null-terminated.|
+|Type|Field     |Description                                                                                          |
+|----|----------|-----------------------------------------------------------------------------------------------------|
+|u8  |num_params|The number of parameters the functions has.                                                          |
+|u8  |name_len  |The length of the external function name, in bytes. Excluding the null-terminate character.          |
+|u8[]|name      |The name of the external function, where the size is defined by @name_len. Names are null-terminated.|
 
 # Bytecode exported functions
 ## Exported functions layout
-|Type             |Field             |Description                                                                              |
-|-----------------|------------------|-----------------------------------------------------------------------------------------|
-|u16              |num_export_func   |The number of exported functions.                                                        |
-|u32              |export_funcs_size |The size of the exported functions section, in bytes.                                    |
-|Exported function|Exported functions|Multiple exported functions, where the number of functions is defined by @num_export_func|
+|Type               |Field             |Description                                                                              |
+|-------------------|------------------|-----------------------------------------------------------------------------------------|
+|u16                |num_export_func   |The number of exported functions.                                                        |
+|u32                |export_funcs_size |The size of all exported functions, in bytes.                                            |
+|Exported function[]|Exported functions|Multiple exported functions, where the number of functions is defined by @num_export_func|
 
 ## Exported function
 |Type|Field             |Description                                                                                                               |
@@ -104,7 +122,21 @@ The versions in the header only changes for every release, not every change.
 |u32 |instruction_offset|The offset in the instruction data where the exported function is defined. Is always 0 until the program has been started.|
 |u8  |num_args          |The number of arguments the functions has.                                                                                |
 |u8  |name_len          |The length of the exported function name, in bytes. Excluding the null-terminate character.                               |
-|u8* |name              |The name of the exported function, where the size is defined by @name_len. Names are null-terminated.                     |
+|u8[]|name              |The name of the exported function, where the size is defined by @name_len. Names are null-terminated.                     |
+
+# Bytecode imports
+## Imports layout
+|Type    |Field       |Description                                                              |
+|--------|------------|-------------------------------------------------------------------------|
+|u8      |num_imports |The number of imports.                                                   |
+|u32     |imports_size|The size of all imports, in bytes.                                       |
+|Import[]|Import      |Multiple imports, where the number of imports is defined by @num_imports.|
+
+## Import
+|Type|Field                |Description                                                                             |
+|----|---------------------|----------------------------------------------------------------------------------------|
+|u32 |function_index       |The index in the bytecode where function header begins for the imported file.           |
+|u32 |extern_function_index|The index in the bytecode where the extern function header begins for the imported file.|
 
 # Bytecode instructions
 ## Instructions layout
diff --git a/doc/IMPLEMENTATION.md b/doc/IMPLEMENTATION.md
deleted file mode 100644
index 387c6eb..0000000
--- a/doc/IMPLEMENTATION.md
+++ /dev/null
@@ -1,21 +0,0 @@
-# Goal
-1. In the first stage the parser parses multiple files at the same time using multiple threads.
-The tokenization should be done without storing the tokens in a list (streaming) but AST needs to be stored in a list
-because the compiler needs to support out of order declarations.
-2. In the second stage the ast is handled using multiple threads. In this stage, variables, parameters
-and types are defined and resolved and if a type is defined after there is a reference to it,
-then the compiler first resolves that type. There are flags set to make sure there aren't recursive dependencies.
-3. In the third stage the resolved ast is used to create SSA form (static single assignment form). If optimization is
-enabled then then some inlining for ast is done by copying ast from functions to the places they are called from
-before the SSA is created.
-4. In the fourth stage the SSA form is used to create the bytecode. If optimization is enabled then the SSA form
-is optimized before creating the bytecode.
-5. If optimization is enabled then the bytecode is optimized.
-
-# Progress
-1. Parsing using multiple threads is done, but the parser is not finished.
-2. Resolving ast using multiple threads is done, but the ast resolver is not finished.
-3. Generating ssa using multiple threads is done, but the ssa generator is not finished.
-4. Generating bytecode using multiple threads is done, but the bytecode generator is not finished.
-Currently it generates C code.
-5. Not started.
\ No newline at end of file