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#include "wasm_compile.h"
#include "wasm.h"
#include "stack_machine_instruction.h"
struct translation {
FILE *handle;
struct function *function;
struct module *module;
};
/* All functions, that go into function pointer array, start with _ */
/* Translate complex - those routines have to be defined manually */
#define TC(wasm_opcode, name)
static int _translate_call(struct translation *data)
{
uint32_t funcidx;
struct instruction **target;
if (leb_u32(data->handle, &funcidx)) {
PRERR(MSG_BAD_NUM);
return -1;
}
if (funcidx >= data->module->functions_count) {
PRERR(MSG_BAD_IDX("funcidx"));
return -1;
}
target = &data->module->functions[funcidx].translated_body;
return i_call(ptr(target), &data->function->translated_body);
}
static int _translate_local_get(struct translation *data)
{
uint32_t localidx;
uint32_t args_count = data->function->type->arguments_count;
uint32_t locals_count = data->function->locals_count;
uint32_t all_locals_count = args_count + locals_count;
uint64_t offset_on_frame;
struct instruction **expr = &data->function->translated_body;
if (leb_u32(data->handle, &localidx)) {
PRERR(MSG_BAD_NUM);
return -1;
}
if (localidx >= all_locals_count) {
PRERR(MSG_BAD_IDX("localidx"));
return -1;
}
offset_on_frame = all_locals_count - localidx + 1;
if (localidx >= args_count)
offset_on_frame -= 1;
return
i_load (im(STACK_FRAME_BACKUP_ADDR), expr) ||
i_load_p(im(4 * offset_on_frame), expr);
}
static int _translate_const(struct translation *data)
{
uint32_t constant;
if (leb_u32(data->handle, &constant)) {
PRERR(MSG_BAD_NUM);
return -1;
}
return i_const(im(constant), &data->function->translated_body);
}
/* Translate Simple */
#define TS(wasm_opcode, sm_instr) \
static int _translate_##sm_instr(struct translation *data) \
{ \
return i_##sm_instr(&data->function->translated_body); \
}
/* Translate load/store */
static int translate_load_store(struct translation *data,
int (*instr_routine) (struct instruction_data,
struct instruction **))
{
uint32_t align, offset;
if (leb_u32(data->handle, &align) ||
leb_u32(data->handle, &offset)) {
PRERR(MSG_BAD_NUM);
return -1;
}
offset += MEMORY_BOTTOM_ADDR;
return instr_routine(im(offset), &data->function->translated_body);
}
#define TLS(wasm_opcode, sm_instr) \
static int _translate_##sm_instr(struct translation *data) \
{ \
return translate_load_store(data, i_##sm_instr); \
}
/* This inclusion defines functions using macros above */
#include "translate_xmacro.h"
#undef TS
#undef TLS
#undef TC
/* Translate complex */
#define TC(wasm_opcode, name) [wasm_opcode] = _translate_##name,
/* Translate Simple */
#define TS(wasm_opcode, sm_instr) TC(wasm_opcode, sm_instr)
/* Translate load/store */
#define TLS(wasm_opcode, sm_instr) TC(wasm_opcode, sm_instr)
/* The actual array of function pointers is defined here */
static int (*translation_routines[256]) (struct translation *) = {
#include "translate_xmacro.h"
};
#undef TS
#undef TLS
#undef TC
static int translate_expr(struct translation *data, struct functype *exprtype)
{
int wasm_opcode;
while (1) {
wasm_opcode = fgetc(data->handle);
if (wasm_opcode == EOF) {
PRERR(MSG_EOF);
return -1;
}
if (wasm_opcode == WASM_END) {
return 0;
}
if (!translation_routines[wasm_opcode]) {
PRERR("Unknown Wasm opcode: 0x%02x\n", wasm_opcode);
return -1;
}
if (translation_routines[wasm_opcode](data))
return -1;
}
}
int translate(FILE *handle, struct function *function, struct module *module)
{
struct instruction **expr = &function->translated_body;
uint32_t args_count = function->type->arguments_count;
uint32_t locals_count = function->locals_count;
uint32_t all_locals_count = args_count + locals_count;
size_t i;
struct translation data = {.handle = handle,
.function = function,
.module = module};
if (locals_count + (uint64_t) args_count > STACK_TOP_ADDR * 4) {
PRERR("Too many locals in a function\n");
goto fail;
}
for (i = locals_count + 3; i; i--) {
if (i_const(im(0), expr))
goto fail;
}
/* function prologue */
if (i_get_frame( expr) ||
i_tee ( expr) ||
i_load (im(STACK_FRAME_BACKUP_ADDR), expr) ||
i_store_p (im(0x0), expr) ||
i_store (im(STACK_FRAME_BACKUP_ADDR), expr))
goto fail;
/* actual function body */
if (translate_expr(&data, function->type))
goto fail;
/* function epilogue */
if (function->type->result) {
if (i_load (im(STACK_FRAME_BACKUP_ADDR), expr) ||
i_swap ( expr) ||
i_store_p(im(4 * (2 + all_locals_count - 1)), expr) ||
i_load (im(STACK_FRAME_BACKUP_ADDR), expr) ||
i_tee ( expr) ||
i_tee ( expr) ||
i_load_p (im(4 * (1 + locals_count)), expr) ||
i_store_p(im(4 * (2 + all_locals_count - 2)), expr) ||
i_load_p (im(0), expr) ||
i_store (im(STACK_FRAME_BACKUP_ADDR), expr))
goto fail;
} else {
/* It's a bit shorter if we don't return anything */
if (i_load (im(STACK_FRAME_BACKUP_ADDR), expr) ||
i_tee ( expr) ||
i_tee ( expr) ||
i_load_p (im(4 * (1 + locals_count)), expr) ||
i_store_p(im(4 * (2 + all_locals_count - 1)), expr) ||
i_load_p (im(0), expr) ||
i_store (im(STACK_FRAME_BACKUP_ADDR), expr))
goto fail;
}
i = locals_count + args_count + 2 + (function->type->result ? 0 : 1);
while (i--) {
if (i_drop(expr))
goto fail;
}
if (i_ret(expr))
goto fail;
return 0;
fail:
PRERR("Couldn't translate function to stack machine\n");
free_expr(*expr);
function->translated_body = NULL;
return -1;
}
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