fixed interpreter

This commit is contained in:
Daniel Knüttel 2018-10-03 23:26:27 +02:00
parent bb07a050e6
commit ce9734b57d
2 changed files with 109 additions and 31 deletions

View File

@ -1,17 +1,21 @@
#include <stdlib.h>
#include <stdio.h>
#include "interpreter.h"
machine_state_t machine_state_t_new( void * cache_function_data
, size_t program_size
, size_t cache_size
, size_t memory_size
, size_t (* cache_block)(uint16_t * cache
, uint16_t offset
, size_t cache_size
, void * cache_function_data)
, dispatch_tree_t method_dispatcher)
{
machine_state_t state = malloc(sizeof(struct machine_state_s));
if(!state)
{
@ -23,11 +27,21 @@ machine_state_t machine_state_t_new( void * cache_function_data
free(state);
return NULL;
}
uint16_t * memory = calloc(sizeof(uint16_t), memory_size);
if(!memory)
{
free(state);
free(cache);
return NULL;
}
state->program_size = program_size;
state->cache = cache;
state->cache_block = cache_block;
state->cache_size = cache_size;
state->cache_loaded = 0;
state->cache_offset = 0;
state->cache_function_data = cache_function_data;
state->program_counter = 0;
@ -40,6 +54,9 @@ machine_state_t machine_state_t_new( void * cache_function_data
}
state->stack = NULL;
state->memory = memory;
state->memory_size = memory_size;
state->method_dispatcher = method_dispatcher;
return state;
@ -48,15 +65,17 @@ machine_state_t machine_state_t_new( void * cache_function_data
void machine_state_t_del(machine_state_t state)
{
free(state->cache);
free(state->memory);
dispatch_tree_t_del(state->method_dispatcher);
bci_stack_t_del(&(state->stack));
free(state);
}
char update_cache(machine_state_t state)
char update_cache(machine_state_t state, uint16_t offset)
{
// Calculate a clever offset for caching.
uint16_t cache_offset = state->program_counter;
uint16_t cache_offset = offset;
if((cache_offset + state->cache_size)
> state->program_size)
{
@ -78,61 +97,64 @@ char update_cache(machine_state_t state)
{
return 1;
}
state->cache_offset = cache_offset;
state->cache_loaded = 1;
return 0;
}
char machine_state_t_exec_cycle(machine_state_t state)
char machine_state_t_get_word(machine_state_t state, uint16_t offset, uint16_t * result)
{
uint16_t opcode, arg;
// This would be bad.
if(state->program_counter >= state->program_size)
if(offset >= state->program_size)
{
return 0b01000000 | 1;
}
// Calculate the in-cache offset of the program counter.
int32_t offset = state->program_counter - state->cache_offset;
// Calculate the in-cache offset of the desired offset.
int32_t in_cache_offset = offset - state->cache_offset;
// Check if we need to update the cache.
if( offset < 0
if( in_cache_offset < 0
|| !(state->cache_loaded)
// Note:
// +1 for cache starting with 0
// +1 for the argument
|| (offset + 2) > state->cache_size)
)
{
if(update_cache(state))
if(update_cache(state, offset))
{
state->error = 0b01000000 | 2;
return 0b01000000 | 2;
}
// Re-calculate the in-cache offset
offset = state->program_counter - state->cache_offset;
in_cache_offset = offset - state->cache_offset;
}
// Check if the argument is cached.
if(offset + 2 > state->cache_size)
*result = state->cache[in_cache_offset];
return 0;
}
char machine_state_t_exec_cycle(machine_state_t state)
{
char res = 0;
uint16_t opcode;
res = machine_state_t_get_word(state, state->program_counter, &opcode);
if(res)
{
// Because we have cached the program memory above
// there is no way that we can include the argument
// now. There is something wrong.
return 0b01000000 | 3;
return res;
}
opcode = state->cache[offset];
arg = state->cache[offset + 1];
bci_core_method_t method = dispatch_tree_t_dispatch(
state->method_dispatcher
, opcode & BCI_CORE_OPCODE_MASK);
if(!method)
{
state->error = res;
return 0b10000000 | 1;
}
return BCI_CORE_RESULT_APPLICATION_BITS
& method(arg
, opcode & BCI_CORE_SMALL_ARG_MASK
& method( opcode & BCI_CORE_SMALL_ARG_MASK
, state);
}
@ -143,3 +165,27 @@ char machine_state_t_default_afterexec(machine_state_t state, uint8_t argc)
state->program_counter += 1 + argc;
return 0;
}
char machine_state_t_get_mem(machine_state_t state, uint16_t offset, uint16_t * result)
{
if(offset > state->memory_size)
{
state->error = 0b01000000 | 15;
return 0b01000000 | 15;
}
*result = state->memory[offset];
return 0;
}
char machine_state_t_set_mem(machine_state_t state, uint16_t offset, uint16_t data)
{
if(offset > state->memory_size)
{
state->error = 0b01000000 | 15;
return 0b01000000 | 15;
}
state->memory[offset] = data;
return 0;
}

View File

@ -2,11 +2,11 @@
#define bci_interpreter_h__
#include <stddef.h>
#include "base.h"
#include "method_dispatcher.h"
#include "stack.h"
#include "../base.h"
#include "../method_dispatcher/method_dispatcher.h"
#include "../stack.h"
typedef machine_state_s
typedef struct machine_state_s
{
// The size of the program in 16-bit words
uint16_t program_size;
@ -29,13 +29,32 @@ typedef machine_state_s
uint16_t data_reg[BCI_CORE_NUM_REG];
bci_stack_t stack;
size_t memory_size;
uint16_t * memory;
dispatch_tree_t method_dispatcher;
// Possible Error Codes:
// 0b01xxxxxx: memory related internal error
// 0b10xxxxxx: core method related internal error
// 0b00xxxxxx: application related internal error
//
//
// 0b01000000 | 1: Program offset out of bounds
// 0b01000000 | 2: Failed to cache new data
// 0b01000000 | 15: Memory offset out of bounds
//
//
// 0b10000000 | 1: Unknown opcode
char error;
} * machine_state_t;
machine_state_t machine_state_t_new( void * cache_function_data
, size_t program_size
, size_t cache_size
, size_t memory_size
, size_t (* cache_block)(uint16_t * cache
, uint16_t offset
, size_t cache_size
@ -57,9 +76,8 @@ void machine_state_t_del(machine_state_t state);
* - 0b01XXXXXX
* Error in the internal memory management (i.e. program counter out
* of bounds)
* - 0b01000000 | 1: program_counter > program_size
* - 0b01000000 | 1: program_counter or argument offset > program_size
* - 0b01000000 | 2: failed to cache new data
* - 0b01000000 | 3: argument is out of program bounds
*
* - 0b10XXXXXX
* Error while dispatching the method
@ -76,4 +94,18 @@ char machine_state_t_exec_cycle(machine_state_t state);
* */
char machine_state_t_default_afterexec(machine_state_t state, uint8_t argc);
/*
* Get the word at offset in the program memory.
* Returns 0 on success, a non-zero value otherwise.
*
* It will set state->error appropiately.
* */
char machine_state_t_get_word(machine_state_t state, uint16_t offset, uint16_t * result);
/*
* Get the word at offset in the RAM-alike memory.
* Works like machine_state_t_get_word.
* */
char machine_state_t_get_mem(machine_state_t state, uint16_t offset, uint16_t * result);
char machine_state_t_set_mem(machine_state_t state, uint16_t offset, uint16_t data);
#endif