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emitnative.c
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/*
* This file is part of the MicroPython project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2013, 2014 Damien P. George
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
// Essentially normal Python has 1 type: Python objects
// Viper has more than 1 type, and is just a more complicated (a superset of) Python.
// If you declare everything in Viper as a Python object (ie omit type decls) then
// it should in principle be exactly the same as Python native.
// Having types means having more opcodes, like binary_op_nat_nat, binary_op_nat_obj etc.
// In practice we won't have a VM but rather do this in asm which is actually very minimal.
// Because it breaks strict Python equivalence it should be a completely separate
// decorator. It breaks equivalence because overflow on integers wraps around.
// It shouldn't break equivalence if you don't use the new types, but since the
// type decls might be used in normal Python for other reasons, it's probably safest,
// cleanest and clearest to make it a separate decorator.
// Actually, it does break equivalence because integers default to native integers,
// not Python objects.
// for x in l[0:8]: can be compiled into a native loop if l has pointer type
#include <stdio.h>
#include <string.h>
#include <assert.h>
#include "py/nlr.h"
#include "py/emit.h"
#include "py/bc.h"
#if 0 // print debugging info
#define DEBUG_PRINT (1)
#define DEBUG_printf DEBUG_printf
#else // don't print debugging info
#define DEBUG_printf(...) (void)0
#endif
// wrapper around everything in this file
#if (MICROPY_EMIT_X64 && N_X64) \
|| (MICROPY_EMIT_X86 && N_X86) \
|| (MICROPY_EMIT_THUMB && N_THUMB) \
|| (MICROPY_EMIT_ARM && N_ARM) \
|| (MICROPY_EMIT_XTENSA && N_XTENSA) \
// this is defined so that the assembler exports generic assembler API macros
#define GENERIC_ASM_API (1)
#if N_X64
// x64 specific stuff
#include "py/asmx64.h"
#define EXPORT_FUN(name) emit_native_x64_##name
#elif N_X86
// x86 specific stuff
STATIC byte mp_f_n_args[MP_F_NUMBER_OF] = {
[MP_F_CONVERT_OBJ_TO_NATIVE] = 2,
[MP_F_CONVERT_NATIVE_TO_OBJ] = 2,
[MP_F_LOAD_NAME] = 1,
[MP_F_LOAD_GLOBAL] = 1,
[MP_F_LOAD_BUILD_CLASS] = 0,
[MP_F_LOAD_ATTR] = 2,
[MP_F_LOAD_METHOD] = 3,
[MP_F_LOAD_SUPER_METHOD] = 2,
[MP_F_STORE_NAME] = 2,
[MP_F_STORE_GLOBAL] = 2,
[MP_F_STORE_ATTR] = 3,
[MP_F_OBJ_SUBSCR] = 3,
[MP_F_OBJ_IS_TRUE] = 1,
[MP_F_UNARY_OP] = 2,
[MP_F_BINARY_OP] = 3,
[MP_F_BUILD_TUPLE] = 2,
[MP_F_BUILD_LIST] = 2,
[MP_F_LIST_APPEND] = 2,
[MP_F_BUILD_MAP] = 1,
[MP_F_STORE_MAP] = 3,
#if MICROPY_PY_BUILTINS_SET
[MP_F_BUILD_SET] = 2,
[MP_F_STORE_SET] = 2,
#endif
[MP_F_MAKE_FUNCTION_FROM_RAW_CODE] = 3,
[MP_F_NATIVE_CALL_FUNCTION_N_KW] = 3,
[MP_F_CALL_METHOD_N_KW] = 3,
[MP_F_CALL_METHOD_N_KW_VAR] = 3,
[MP_F_NATIVE_GETITER] = 2,
[MP_F_NATIVE_ITERNEXT] = 1,
[MP_F_NLR_PUSH] = 1,
[MP_F_NLR_POP] = 0,
[MP_F_NATIVE_RAISE] = 1,
[MP_F_IMPORT_NAME] = 3,
[MP_F_IMPORT_FROM] = 2,
[MP_F_IMPORT_ALL] = 1,
#if MICROPY_PY_BUILTINS_SLICE
[MP_F_NEW_SLICE] = 3,
#endif
[MP_F_UNPACK_SEQUENCE] = 3,
[MP_F_UNPACK_EX] = 3,
[MP_F_DELETE_NAME] = 1,
[MP_F_DELETE_GLOBAL] = 1,
[MP_F_NEW_CELL] = 1,
[MP_F_MAKE_CLOSURE_FROM_RAW_CODE] = 3,
[MP_F_SETUP_CODE_STATE] = 5,
};
#include "py/asmx86.h"
#define EXPORT_FUN(name) emit_native_x86_##name
#elif N_THUMB
// thumb specific stuff
#include "py/asmthumb.h"
#define EXPORT_FUN(name) emit_native_thumb_##name
#elif N_ARM
// ARM specific stuff
#include "py/asmarm.h"
#define EXPORT_FUN(name) emit_native_arm_##name
#elif N_XTENSA
// Xtensa specific stuff
#include "py/asmxtensa.h"
#define EXPORT_FUN(name) emit_native_xtensa_##name
#else
#error unknown native emitter
#endif
#define EMIT_NATIVE_VIPER_TYPE_ERROR(emit, ...) do { \
*emit->error_slot = mp_obj_new_exception_msg_varg(&mp_type_ViperTypeError, __VA_ARGS__); \
} while (0)
typedef enum {
STACK_VALUE,
STACK_REG,
STACK_IMM,
} stack_info_kind_t;
// these enums must be distinct and the bottom 4 bits
// must correspond to the correct MP_NATIVE_TYPE_xxx value
typedef enum {
VTYPE_PYOBJ = 0x00 | MP_NATIVE_TYPE_OBJ,
VTYPE_BOOL = 0x00 | MP_NATIVE_TYPE_BOOL,
VTYPE_INT = 0x00 | MP_NATIVE_TYPE_INT,
VTYPE_UINT = 0x00 | MP_NATIVE_TYPE_UINT,
VTYPE_PTR = 0x00 | MP_NATIVE_TYPE_PTR,
VTYPE_PTR8 = 0x00 | MP_NATIVE_TYPE_PTR8,
VTYPE_PTR16 = 0x00 | MP_NATIVE_TYPE_PTR16,
VTYPE_PTR32 = 0x00 | MP_NATIVE_TYPE_PTR32,
VTYPE_PTR_NONE = 0x50 | MP_NATIVE_TYPE_PTR,
VTYPE_UNBOUND = 0x60 | MP_NATIVE_TYPE_OBJ,
VTYPE_BUILTIN_CAST = 0x70 | MP_NATIVE_TYPE_OBJ,
} vtype_kind_t;
STATIC qstr vtype_to_qstr(vtype_kind_t vtype) {
switch (vtype) {
case VTYPE_PYOBJ: return MP_QSTR_object;
case VTYPE_BOOL: return MP_QSTR_bool;
case VTYPE_INT: return MP_QSTR_int;
case VTYPE_UINT: return MP_QSTR_uint;
case VTYPE_PTR: return MP_QSTR_ptr;
case VTYPE_PTR8: return MP_QSTR_ptr8;
case VTYPE_PTR16: return MP_QSTR_ptr16;
case VTYPE_PTR32: return MP_QSTR_ptr32;
case VTYPE_PTR_NONE: default: return MP_QSTR_None;
}
}
typedef struct _stack_info_t {
vtype_kind_t vtype;
stack_info_kind_t kind;
union {
int u_reg;
mp_int_t u_imm;
} data;
} stack_info_t;
struct _emit_t {
mp_obj_t *error_slot;
int pass;
bool do_viper_types;
vtype_kind_t return_vtype;
mp_uint_t local_vtype_alloc;
vtype_kind_t *local_vtype;
mp_uint_t stack_info_alloc;
stack_info_t *stack_info;
vtype_kind_t saved_stack_vtype;
int prelude_offset;
int const_table_offset;
int n_state;
int stack_start;
int stack_size;
bool last_emit_was_return_value;
scope_t *scope;
ASM_T *as;
};
emit_t *EXPORT_FUN(new)(mp_obj_t *error_slot, mp_uint_t max_num_labels) {
emit_t *emit = m_new0(emit_t, 1);
emit->error_slot = error_slot;
emit->as = m_new0(ASM_T, 1);
mp_asm_base_init(&emit->as->base, max_num_labels);
return emit;
}
void EXPORT_FUN(free)(emit_t *emit) {
mp_asm_base_deinit(&emit->as->base, false);
m_del_obj(ASM_T, emit->as);
m_del(vtype_kind_t, emit->local_vtype, emit->local_vtype_alloc);
m_del(stack_info_t, emit->stack_info, emit->stack_info_alloc);
m_del_obj(emit_t, emit);
}
STATIC void emit_native_set_native_type(emit_t *emit, mp_uint_t op, mp_uint_t arg1, qstr arg2) {
switch (op) {
case MP_EMIT_NATIVE_TYPE_ENABLE:
emit->do_viper_types = arg1;
break;
default: {
vtype_kind_t type;
switch (arg2) {
case MP_QSTR_object: type = VTYPE_PYOBJ; break;
case MP_QSTR_bool: type = VTYPE_BOOL; break;
case MP_QSTR_int: type = VTYPE_INT; break;
case MP_QSTR_uint: type = VTYPE_UINT; break;
case MP_QSTR_ptr: type = VTYPE_PTR; break;
case MP_QSTR_ptr8: type = VTYPE_PTR8; break;
case MP_QSTR_ptr16: type = VTYPE_PTR16; break;
case MP_QSTR_ptr32: type = VTYPE_PTR32; break;
default: EMIT_NATIVE_VIPER_TYPE_ERROR(emit, "unknown type '%q'", arg2); return;
}
if (op == MP_EMIT_NATIVE_TYPE_RETURN) {
emit->return_vtype = type;
} else {
assert(arg1 < emit->local_vtype_alloc);
emit->local_vtype[arg1] = type;
}
break;
}
}
}
STATIC void emit_pre_pop_reg(emit_t *emit, vtype_kind_t *vtype, int reg_dest);
STATIC void emit_post_push_reg(emit_t *emit, vtype_kind_t vtype, int reg);
STATIC void emit_native_load_fast(emit_t *emit, qstr qst, mp_uint_t local_num);
STATIC void emit_native_store_fast(emit_t *emit, qstr qst, mp_uint_t local_num);
#define STATE_START (sizeof(mp_code_state_t) / sizeof(mp_uint_t))
STATIC void emit_native_start_pass(emit_t *emit, pass_kind_t pass, scope_t *scope) {
DEBUG_printf("start_pass(pass=%u, scope=%p)\n", pass, scope);
emit->pass = pass;
emit->stack_start = 0;
emit->stack_size = 0;
emit->last_emit_was_return_value = false;
emit->scope = scope;
// allocate memory for keeping track of the types of locals
if (emit->local_vtype_alloc < scope->num_locals) {
emit->local_vtype = m_renew(vtype_kind_t, emit->local_vtype, emit->local_vtype_alloc, scope->num_locals);
emit->local_vtype_alloc = scope->num_locals;
}
// allocate memory for keeping track of the objects on the stack
// XXX don't know stack size on entry, and it should be maximum over all scopes
// XXX this is such a big hack and really needs to be fixed
if (emit->stack_info == NULL) {
emit->stack_info_alloc = scope->stack_size + 200;
emit->stack_info = m_new(stack_info_t, emit->stack_info_alloc);
}
// set default type for return
emit->return_vtype = VTYPE_PYOBJ;
// set default type for arguments
mp_uint_t num_args = emit->scope->num_pos_args + emit->scope->num_kwonly_args;
if (scope->scope_flags & MP_SCOPE_FLAG_VARARGS) {
num_args += 1;
}
if (scope->scope_flags & MP_SCOPE_FLAG_VARKEYWORDS) {
num_args += 1;
}
for (mp_uint_t i = 0; i < num_args; i++) {
emit->local_vtype[i] = VTYPE_PYOBJ;
}
// local variables begin unbound, and have unknown type
for (mp_uint_t i = num_args; i < emit->local_vtype_alloc; i++) {
emit->local_vtype[i] = VTYPE_UNBOUND;
}
// values on stack begin unbound
for (mp_uint_t i = 0; i < emit->stack_info_alloc; i++) {
emit->stack_info[i].kind = STACK_VALUE;
emit->stack_info[i].vtype = VTYPE_UNBOUND;
}
mp_asm_base_start_pass(&emit->as->base, pass == MP_PASS_EMIT ? MP_ASM_PASS_EMIT : MP_ASM_PASS_COMPUTE);
// generate code for entry to function
if (emit->do_viper_types) {
// right now we have a restriction of maximum of 4 arguments
if (scope->num_pos_args >= 5) {
EMIT_NATIVE_VIPER_TYPE_ERROR(emit, "Viper functions don't currently support more than 4 arguments");
return;
}
// entry to function
int num_locals = 0;
if (pass > MP_PASS_SCOPE) {
num_locals = scope->num_locals - REG_LOCAL_NUM;
if (num_locals < 0) {
num_locals = 0;
}
emit->stack_start = num_locals;
num_locals += scope->stack_size;
}
ASM_ENTRY(emit->as, num_locals);
// TODO don't load r7 if we don't need it
#if N_THUMB
asm_thumb_mov_reg_i32(emit->as, ASM_THUMB_REG_R7, (mp_uint_t)mp_fun_table);
#elif N_ARM
asm_arm_mov_reg_i32(emit->as, ASM_ARM_REG_R7, (mp_uint_t)mp_fun_table);
#endif
#if N_X86
for (int i = 0; i < scope->num_pos_args; i++) {
if (i == 0) {
asm_x86_mov_arg_to_r32(emit->as, i, REG_LOCAL_1);
} else if (i == 1) {
asm_x86_mov_arg_to_r32(emit->as, i, REG_LOCAL_2);
} else if (i == 2) {
asm_x86_mov_arg_to_r32(emit->as, i, REG_LOCAL_3);
} else {
asm_x86_mov_arg_to_r32(emit->as, i, REG_TEMP0);
asm_x86_mov_r32_to_local(emit->as, REG_TEMP0, i - REG_LOCAL_NUM);
}
}
#else
for (int i = 0; i < scope->num_pos_args; i++) {
if (i == 0) {
ASM_MOV_REG_REG(emit->as, REG_LOCAL_1, REG_ARG_1);
} else if (i == 1) {
ASM_MOV_REG_REG(emit->as, REG_LOCAL_2, REG_ARG_2);
} else if (i == 2) {
ASM_MOV_REG_REG(emit->as, REG_LOCAL_3, REG_ARG_3);
} else {
assert(i == 3); // should be true; max 4 args is checked above
ASM_MOV_REG_TO_LOCAL(emit->as, REG_ARG_4, i - REG_LOCAL_NUM);
}
}
#endif
} else {
// work out size of state (locals plus stack)
emit->n_state = scope->num_locals + scope->stack_size;
// allocate space on C-stack for code_state structure, which includes state
ASM_ENTRY(emit->as, STATE_START + emit->n_state);
// TODO don't load r7 if we don't need it
#if N_THUMB
asm_thumb_mov_reg_i32(emit->as, ASM_THUMB_REG_R7, (mp_uint_t)mp_fun_table);
#elif N_ARM
asm_arm_mov_reg_i32(emit->as, ASM_ARM_REG_R7, (mp_uint_t)mp_fun_table);
#endif
// prepare incoming arguments for call to mp_setup_code_state
#if N_X86
asm_x86_mov_arg_to_r32(emit->as, 0, REG_ARG_1);
asm_x86_mov_arg_to_r32(emit->as, 1, REG_ARG_2);
asm_x86_mov_arg_to_r32(emit->as, 2, REG_ARG_3);
asm_x86_mov_arg_to_r32(emit->as, 3, REG_ARG_4);
#endif
// set code_state.fun_bc
ASM_MOV_REG_TO_LOCAL(emit->as, REG_ARG_1, offsetof(mp_code_state_t, fun_bc) / sizeof(uintptr_t));
// set code_state.ip (offset from start of this function to prelude info)
// XXX this encoding may change size
ASM_MOV_IMM_TO_LOCAL_USING(emit->as, emit->prelude_offset, offsetof(mp_code_state_t, ip) / sizeof(uintptr_t), REG_ARG_1);
// put address of code_state into first arg
ASM_MOV_LOCAL_ADDR_TO_REG(emit->as, 0, REG_ARG_1);
// call mp_setup_code_state to prepare code_state structure
#if N_THUMB
asm_thumb_bl_ind(emit->as, mp_fun_table[MP_F_SETUP_CODE_STATE], MP_F_SETUP_CODE_STATE, ASM_THUMB_REG_R4);
#elif N_ARM
asm_arm_bl_ind(emit->as, mp_fun_table[MP_F_SETUP_CODE_STATE], MP_F_SETUP_CODE_STATE, ASM_ARM_REG_R4);
#else
ASM_CALL_IND(emit->as, mp_fun_table[MP_F_SETUP_CODE_STATE], MP_F_SETUP_CODE_STATE);
#endif
// cache some locals in registers
if (scope->num_locals > 0) {
ASM_MOV_LOCAL_TO_REG(emit->as, STATE_START + emit->n_state - 1 - 0, REG_LOCAL_1);
if (scope->num_locals > 1) {
ASM_MOV_LOCAL_TO_REG(emit->as, STATE_START + emit->n_state - 1 - 1, REG_LOCAL_2);
if (scope->num_locals > 2) {
ASM_MOV_LOCAL_TO_REG(emit->as, STATE_START + emit->n_state - 1 - 2, REG_LOCAL_3);
}
}
}
// set the type of closed over variables
for (mp_uint_t i = 0; i < scope->id_info_len; i++) {
id_info_t *id = &scope->id_info[i];
if (id->kind == ID_INFO_KIND_CELL) {
emit->local_vtype[id->local_num] = VTYPE_PYOBJ;
}
}
}
}
STATIC void emit_native_end_pass(emit_t *emit) {
if (!emit->last_emit_was_return_value) {
ASM_EXIT(emit->as);
}
if (!emit->do_viper_types) {
emit->prelude_offset = mp_asm_base_get_code_pos(&emit->as->base);
mp_asm_base_data(&emit->as->base, 1, 0x80 | ((emit->n_state >> 7) & 0x7f));
mp_asm_base_data(&emit->as->base, 1, emit->n_state & 0x7f);
mp_asm_base_data(&emit->as->base, 1, 0); // n_exc_stack
mp_asm_base_data(&emit->as->base, 1, emit->scope->scope_flags);
mp_asm_base_data(&emit->as->base, 1, emit->scope->num_pos_args);
mp_asm_base_data(&emit->as->base, 1, emit->scope->num_kwonly_args);
mp_asm_base_data(&emit->as->base, 1, emit->scope->num_def_pos_args);
// write code info
#if MICROPY_PERSISTENT_CODE
mp_asm_base_data(&emit->as->base, 1, 5);
mp_asm_base_data(&emit->as->base, 1, emit->scope->simple_name);
mp_asm_base_data(&emit->as->base, 1, emit->scope->simple_name >> 8);
mp_asm_base_data(&emit->as->base, 1, emit->scope->source_file);
mp_asm_base_data(&emit->as->base, 1, emit->scope->source_file >> 8);
#else
mp_asm_base_data(&emit->as->base, 1, 1);
#endif
// bytecode prelude: initialise closed over variables
for (int i = 0; i < emit->scope->id_info_len; i++) {
id_info_t *id = &emit->scope->id_info[i];
if (id->kind == ID_INFO_KIND_CELL) {
assert(id->local_num < 255);
mp_asm_base_data(&emit->as->base, 1, id->local_num); // write the local which should be converted to a cell
}
}
mp_asm_base_data(&emit->as->base, 1, 255); // end of list sentinel
mp_asm_base_align(&emit->as->base, ASM_WORD_SIZE);
emit->const_table_offset = mp_asm_base_get_code_pos(&emit->as->base);
// write argument names as qstr objects
// see comment in corresponding part of emitbc.c about the logic here
for (int i = 0; i < emit->scope->num_pos_args + emit->scope->num_kwonly_args; i++) {
qstr qst = MP_QSTR__star_;
for (int j = 0; j < emit->scope->id_info_len; ++j) {
id_info_t *id = &emit->scope->id_info[j];
if ((id->flags & ID_FLAG_IS_PARAM) && id->local_num == i) {
qst = id->qst;
break;
}
}
mp_asm_base_data(&emit->as->base, ASM_WORD_SIZE, (mp_uint_t)MP_OBJ_NEW_QSTR(qst));
}
}
ASM_END_PASS(emit->as);
// check stack is back to zero size
assert(emit->stack_size == 0);
if (emit->pass == MP_PASS_EMIT) {
void *f = mp_asm_base_get_code(&emit->as->base);
mp_uint_t f_len = mp_asm_base_get_code_size(&emit->as->base);
// compute type signature
// note that the lower 4 bits of a vtype are tho correct MP_NATIVE_TYPE_xxx
mp_uint_t type_sig = emit->return_vtype & 0xf;
for (mp_uint_t i = 0; i < emit->scope->num_pos_args; i++) {
type_sig |= (emit->local_vtype[i] & 0xf) << (i * 4 + 4);
}
mp_emit_glue_assign_native(emit->scope->raw_code,
emit->do_viper_types ? MP_CODE_NATIVE_VIPER : MP_CODE_NATIVE_PY,
f, f_len, (mp_uint_t*)((byte*)f + emit->const_table_offset),
emit->scope->num_pos_args, emit->scope->scope_flags, type_sig);
}
}
STATIC bool emit_native_last_emit_was_return_value(emit_t *emit) {
return emit->last_emit_was_return_value;
}
STATIC void adjust_stack(emit_t *emit, mp_int_t stack_size_delta) {
assert((mp_int_t)emit->stack_size + stack_size_delta >= 0);
emit->stack_size += stack_size_delta;
if (emit->pass > MP_PASS_SCOPE && emit->stack_size > emit->scope->stack_size) {
emit->scope->stack_size = emit->stack_size;
}
#ifdef DEBUG_PRINT
DEBUG_printf(" adjust_stack; stack_size=%d+%d; stack now:", emit->stack_size - stack_size_delta, stack_size_delta);
for (int i = 0; i < emit->stack_size; i++) {
stack_info_t *si = &emit->stack_info[i];
DEBUG_printf(" (v=%d k=%d %d)", si->vtype, si->kind, si->data.u_reg);
}
DEBUG_printf("\n");
#endif
}
STATIC void emit_native_adjust_stack_size(emit_t *emit, mp_int_t delta) {
DEBUG_printf("adjust_stack_size(" INT_FMT ")\n", delta);
// If we are adjusting the stack in a positive direction (pushing) then we
// need to fill in values for the stack kind and vtype of the newly-pushed
// entries. These should be set to "value" (ie not reg or imm) because we
// should only need to adjust the stack due to a jump to this part in the
// code (and hence we have settled the stack before the jump).
for (mp_int_t i = 0; i < delta; i++) {
stack_info_t *si = &emit->stack_info[emit->stack_size + i];
si->kind = STACK_VALUE;
// TODO we don't know the vtype to use here. At the moment this is a
// hack to get the case of multi comparison working.
if (delta == 1) {
si->vtype = emit->saved_stack_vtype;
} else {
si->vtype = VTYPE_PYOBJ;
}
}
adjust_stack(emit, delta);
}
STATIC void emit_native_set_source_line(emit_t *emit, mp_uint_t source_line) {
(void)emit;
(void)source_line;
}
// this must be called at start of emit functions
STATIC void emit_native_pre(emit_t *emit) {
emit->last_emit_was_return_value = false;
}
// depth==0 is top, depth==1 is before top, etc
STATIC stack_info_t *peek_stack(emit_t *emit, mp_uint_t depth) {
return &emit->stack_info[emit->stack_size - 1 - depth];
}
// depth==0 is top, depth==1 is before top, etc
STATIC vtype_kind_t peek_vtype(emit_t *emit, mp_uint_t depth) {
return peek_stack(emit, depth)->vtype;
}
// pos=1 is TOS, pos=2 is next, etc
// use pos=0 for no skipping
STATIC void need_reg_single(emit_t *emit, int reg_needed, int skip_stack_pos) {
skip_stack_pos = emit->stack_size - skip_stack_pos;
for (int i = 0; i < emit->stack_size; i++) {
if (i != skip_stack_pos) {
stack_info_t *si = &emit->stack_info[i];
if (si->kind == STACK_REG && si->data.u_reg == reg_needed) {
si->kind = STACK_VALUE;
ASM_MOV_REG_TO_LOCAL(emit->as, si->data.u_reg, emit->stack_start + i);
}
}
}
}
STATIC void need_reg_all(emit_t *emit) {
for (int i = 0; i < emit->stack_size; i++) {
stack_info_t *si = &emit->stack_info[i];
if (si->kind == STACK_REG) {
si->kind = STACK_VALUE;
ASM_MOV_REG_TO_LOCAL(emit->as, si->data.u_reg, emit->stack_start + i);
}
}
}
STATIC void need_stack_settled(emit_t *emit) {
DEBUG_printf(" need_stack_settled; stack_size=%d\n", emit->stack_size);
for (int i = 0; i < emit->stack_size; i++) {
stack_info_t *si = &emit->stack_info[i];
if (si->kind == STACK_REG) {
DEBUG_printf(" reg(%u) to local(%u)\n", si->data.u_reg, emit->stack_start + i);
si->kind = STACK_VALUE;
ASM_MOV_REG_TO_LOCAL(emit->as, si->data.u_reg, emit->stack_start + i);
}
}
for (int i = 0; i < emit->stack_size; i++) {
stack_info_t *si = &emit->stack_info[i];
if (si->kind == STACK_IMM) {
DEBUG_printf(" imm(" INT_FMT ") to local(%u)\n", si->data.u_imm, emit->stack_start + i);
si->kind = STACK_VALUE;
ASM_MOV_IMM_TO_LOCAL_USING(emit->as, si->data.u_imm, emit->stack_start + i, REG_TEMP0);
}
}
}
// pos=1 is TOS, pos=2 is next, etc
STATIC void emit_access_stack(emit_t *emit, int pos, vtype_kind_t *vtype, int reg_dest) {
need_reg_single(emit, reg_dest, pos);
stack_info_t *si = &emit->stack_info[emit->stack_size - pos];
*vtype = si->vtype;
switch (si->kind) {
case STACK_VALUE:
ASM_MOV_LOCAL_TO_REG(emit->as, emit->stack_start + emit->stack_size - pos, reg_dest);
break;
case STACK_REG:
if (si->data.u_reg != reg_dest) {
ASM_MOV_REG_REG(emit->as, reg_dest, si->data.u_reg);
}
break;
case STACK_IMM:
ASM_MOV_IMM_TO_REG(emit->as, si->data.u_imm, reg_dest);
break;
}
}
// does an efficient X=pop(); discard(); push(X)
// needs a (non-temp) register in case the poped element was stored in the stack
STATIC void emit_fold_stack_top(emit_t *emit, int reg_dest) {
stack_info_t *si = &emit->stack_info[emit->stack_size - 2];
si[0] = si[1];
if (si->kind == STACK_VALUE) {
// if folded element was on the stack we need to put it in a register
ASM_MOV_LOCAL_TO_REG(emit->as, emit->stack_start + emit->stack_size - 1, reg_dest);
si->kind = STACK_REG;
si->data.u_reg = reg_dest;
}
adjust_stack(emit, -1);
}
// If stacked value is in a register and the register is not r1 or r2, then
// *reg_dest is set to that register. Otherwise the value is put in *reg_dest.
STATIC void emit_pre_pop_reg_flexible(emit_t *emit, vtype_kind_t *vtype, int *reg_dest, int not_r1, int not_r2) {
emit->last_emit_was_return_value = false;
stack_info_t *si = peek_stack(emit, 0);
if (si->kind == STACK_REG && si->data.u_reg != not_r1 && si->data.u_reg != not_r2) {
*vtype = si->vtype;
*reg_dest = si->data.u_reg;
need_reg_single(emit, *reg_dest, 1);
} else {
emit_access_stack(emit, 1, vtype, *reg_dest);
}
adjust_stack(emit, -1);
}
STATIC void emit_pre_pop_discard(emit_t *emit) {
emit->last_emit_was_return_value = false;
adjust_stack(emit, -1);
}
STATIC void emit_pre_pop_reg(emit_t *emit, vtype_kind_t *vtype, int reg_dest) {
emit->last_emit_was_return_value = false;
emit_access_stack(emit, 1, vtype, reg_dest);
adjust_stack(emit, -1);
}
STATIC void emit_pre_pop_reg_reg(emit_t *emit, vtype_kind_t *vtypea, int rega, vtype_kind_t *vtypeb, int regb) {
emit_pre_pop_reg(emit, vtypea, rega);
emit_pre_pop_reg(emit, vtypeb, regb);
}
STATIC void emit_pre_pop_reg_reg_reg(emit_t *emit, vtype_kind_t *vtypea, int rega, vtype_kind_t *vtypeb, int regb, vtype_kind_t *vtypec, int regc) {
emit_pre_pop_reg(emit, vtypea, rega);
emit_pre_pop_reg(emit, vtypeb, regb);
emit_pre_pop_reg(emit, vtypec, regc);
}
STATIC void emit_post(emit_t *emit) {
(void)emit;
}
STATIC void emit_post_top_set_vtype(emit_t *emit, vtype_kind_t new_vtype) {
stack_info_t *si = &emit->stack_info[emit->stack_size - 1];
si->vtype = new_vtype;
}
STATIC void emit_post_push_reg(emit_t *emit, vtype_kind_t vtype, int reg) {
stack_info_t *si = &emit->stack_info[emit->stack_size];
si->vtype = vtype;
si->kind = STACK_REG;
si->data.u_reg = reg;
adjust_stack(emit, 1);
}
STATIC void emit_post_push_imm(emit_t *emit, vtype_kind_t vtype, mp_int_t imm) {
stack_info_t *si = &emit->stack_info[emit->stack_size];
si->vtype = vtype;
si->kind = STACK_IMM;
si->data.u_imm = imm;
adjust_stack(emit, 1);
}
STATIC void emit_post_push_reg_reg(emit_t *emit, vtype_kind_t vtypea, int rega, vtype_kind_t vtypeb, int regb) {
emit_post_push_reg(emit, vtypea, rega);
emit_post_push_reg(emit, vtypeb, regb);
}
STATIC void emit_post_push_reg_reg_reg(emit_t *emit, vtype_kind_t vtypea, int rega, vtype_kind_t vtypeb, int regb, vtype_kind_t vtypec, int regc) {
emit_post_push_reg(emit, vtypea, rega);
emit_post_push_reg(emit, vtypeb, regb);
emit_post_push_reg(emit, vtypec, regc);
}
STATIC void emit_post_push_reg_reg_reg_reg(emit_t *emit, vtype_kind_t vtypea, int rega, vtype_kind_t vtypeb, int regb, vtype_kind_t vtypec, int regc, vtype_kind_t vtyped, int regd) {
emit_post_push_reg(emit, vtypea, rega);
emit_post_push_reg(emit, vtypeb, regb);
emit_post_push_reg(emit, vtypec, regc);
emit_post_push_reg(emit, vtyped, regd);
}
STATIC void emit_call(emit_t *emit, mp_fun_kind_t fun_kind) {
need_reg_all(emit);
ASM_CALL_IND(emit->as, mp_fun_table[fun_kind], fun_kind);
}
STATIC void emit_call_with_imm_arg(emit_t *emit, mp_fun_kind_t fun_kind, mp_int_t arg_val, int arg_reg) {
need_reg_all(emit);
ASM_MOV_IMM_TO_REG(emit->as, arg_val, arg_reg);
ASM_CALL_IND(emit->as, mp_fun_table[fun_kind], fun_kind);
}
// the first arg is stored in the code aligned on a mp_uint_t boundary
STATIC void emit_call_with_imm_arg_aligned(emit_t *emit, mp_fun_kind_t fun_kind, mp_int_t arg_val, int arg_reg) {
need_reg_all(emit);
ASM_MOV_ALIGNED_IMM_TO_REG(emit->as, arg_val, arg_reg);
ASM_CALL_IND(emit->as, mp_fun_table[fun_kind], fun_kind);
}
STATIC void emit_call_with_2_imm_args(emit_t *emit, mp_fun_kind_t fun_kind, mp_int_t arg_val1, int arg_reg1, mp_int_t arg_val2, int arg_reg2) {
need_reg_all(emit);
ASM_MOV_IMM_TO_REG(emit->as, arg_val1, arg_reg1);
ASM_MOV_IMM_TO_REG(emit->as, arg_val2, arg_reg2);
ASM_CALL_IND(emit->as, mp_fun_table[fun_kind], fun_kind);
}
// the first arg is stored in the code aligned on a mp_uint_t boundary
STATIC void emit_call_with_3_imm_args_and_first_aligned(emit_t *emit, mp_fun_kind_t fun_kind, mp_int_t arg_val1, int arg_reg1, mp_int_t arg_val2, int arg_reg2, mp_int_t arg_val3, int arg_reg3) {
need_reg_all(emit);
ASM_MOV_ALIGNED_IMM_TO_REG(emit->as, arg_val1, arg_reg1);
ASM_MOV_IMM_TO_REG(emit->as, arg_val2, arg_reg2);
ASM_MOV_IMM_TO_REG(emit->as, arg_val3, arg_reg3);
ASM_CALL_IND(emit->as, mp_fun_table[fun_kind], fun_kind);
}
// vtype of all n_pop objects is VTYPE_PYOBJ
// Will convert any items that are not VTYPE_PYOBJ to this type and put them back on the stack.
// If any conversions of non-immediate values are needed, then it uses REG_ARG_1, REG_ARG_2 and REG_RET.
// Otherwise, it does not use any temporary registers (but may use reg_dest before loading it with stack pointer).
STATIC void emit_get_stack_pointer_to_reg_for_pop(emit_t *emit, mp_uint_t reg_dest, mp_uint_t n_pop) {
need_reg_all(emit);
// First, store any immediate values to their respective place on the stack.
for (mp_uint_t i = 0; i < n_pop; i++) {
stack_info_t *si = &emit->stack_info[emit->stack_size - 1 - i];
// must push any imm's to stack
// must convert them to VTYPE_PYOBJ for viper code
if (si->kind == STACK_IMM) {
si->kind = STACK_VALUE;
switch (si->vtype) {
case VTYPE_PYOBJ:
ASM_MOV_IMM_TO_LOCAL_USING(emit->as, si->data.u_imm, emit->stack_start + emit->stack_size - 1 - i, reg_dest);
break;
case VTYPE_BOOL:
if (si->data.u_imm == 0) {
ASM_MOV_IMM_TO_LOCAL_USING(emit->as, (mp_uint_t)mp_const_false, emit->stack_start + emit->stack_size - 1 - i, reg_dest);
} else {
ASM_MOV_IMM_TO_LOCAL_USING(emit->as, (mp_uint_t)mp_const_true, emit->stack_start + emit->stack_size - 1 - i, reg_dest);
}
si->vtype = VTYPE_PYOBJ;
break;
case VTYPE_INT:
case VTYPE_UINT:
ASM_MOV_IMM_TO_LOCAL_USING(emit->as, (uintptr_t)MP_OBJ_NEW_SMALL_INT(si->data.u_imm), emit->stack_start + emit->stack_size - 1 - i, reg_dest);
si->vtype = VTYPE_PYOBJ;
break;
default:
// not handled
mp_not_implemented("conversion to object");
}
}
// verify that this value is on the stack
assert(si->kind == STACK_VALUE);
}
// Second, convert any non-VTYPE_PYOBJ to that type.
for (mp_uint_t i = 0; i < n_pop; i++) {
stack_info_t *si = &emit->stack_info[emit->stack_size - 1 - i];
if (si->vtype != VTYPE_PYOBJ) {
mp_uint_t local_num = emit->stack_start + emit->stack_size - 1 - i;
ASM_MOV_LOCAL_TO_REG(emit->as, local_num, REG_ARG_1);
emit_call_with_imm_arg(emit, MP_F_CONVERT_NATIVE_TO_OBJ, si->vtype, REG_ARG_2); // arg2 = type
ASM_MOV_REG_TO_LOCAL(emit->as, REG_RET, local_num);
si->vtype = VTYPE_PYOBJ;
DEBUG_printf(" convert_native_to_obj(local_num=" UINT_FMT ")\n", local_num);
}
}
// Adujust the stack for a pop of n_pop items, and load the stack pointer into reg_dest.
adjust_stack(emit, -n_pop);
ASM_MOV_LOCAL_ADDR_TO_REG(emit->as, emit->stack_start + emit->stack_size, reg_dest);
}
// vtype of all n_push objects is VTYPE_PYOBJ
STATIC void emit_get_stack_pointer_to_reg_for_push(emit_t *emit, mp_uint_t reg_dest, mp_uint_t n_push) {
need_reg_all(emit);
for (mp_uint_t i = 0; i < n_push; i++) {
emit->stack_info[emit->stack_size + i].kind = STACK_VALUE;
emit->stack_info[emit->stack_size + i].vtype = VTYPE_PYOBJ;
}
ASM_MOV_LOCAL_ADDR_TO_REG(emit->as, emit->stack_start + emit->stack_size, reg_dest);
adjust_stack(emit, n_push);
}
STATIC void emit_native_label_assign(emit_t *emit, mp_uint_t l) {
DEBUG_printf("label_assign(" UINT_FMT ")\n", l);
emit_native_pre(emit);
// need to commit stack because we can jump here from elsewhere
need_stack_settled(emit);
mp_asm_base_label_assign(&emit->as->base, l);
emit_post(emit);
}
STATIC void emit_native_import_name(emit_t *emit, qstr qst) {
DEBUG_printf("import_name %s\n", qstr_str(qst));
// get arguments from stack: arg2 = fromlist, arg3 = level
// if using viper types these arguments must be converted to proper objects
if (emit->do_viper_types) {
// fromlist should be None or a tuple
stack_info_t *top = peek_stack(emit, 0);
if (top->vtype == VTYPE_PTR_NONE) {
emit_pre_pop_discard(emit);
ASM_MOV_IMM_TO_REG(emit->as, (mp_uint_t)mp_const_none, REG_ARG_2);
} else {
vtype_kind_t vtype_fromlist;
emit_pre_pop_reg(emit, &vtype_fromlist, REG_ARG_2);
assert(vtype_fromlist == VTYPE_PYOBJ);
}
// level argument should be an immediate integer
top = peek_stack(emit, 0);
assert(top->vtype == VTYPE_INT && top->kind == STACK_IMM);
ASM_MOV_IMM_TO_REG(emit->as, (mp_uint_t)MP_OBJ_NEW_SMALL_INT(top->data.u_imm), REG_ARG_3);
emit_pre_pop_discard(emit);
} else {
vtype_kind_t vtype_fromlist;
vtype_kind_t vtype_level;
emit_pre_pop_reg_reg(emit, &vtype_fromlist, REG_ARG_2, &vtype_level, REG_ARG_3);
assert(vtype_fromlist == VTYPE_PYOBJ);
assert(vtype_level == VTYPE_PYOBJ);
}
emit_call_with_imm_arg(emit, MP_F_IMPORT_NAME, qst, REG_ARG_1); // arg1 = import name
emit_post_push_reg(emit, VTYPE_PYOBJ, REG_RET);
}
STATIC void emit_native_import_from(emit_t *emit, qstr qst) {
DEBUG_printf("import_from %s\n", qstr_str(qst));
emit_native_pre(emit);
vtype_kind_t vtype_module;
emit_access_stack(emit, 1, &vtype_module, REG_ARG_1); // arg1 = module
assert(vtype_module == VTYPE_PYOBJ);
emit_call_with_imm_arg(emit, MP_F_IMPORT_FROM, qst, REG_ARG_2); // arg2 = import name
emit_post_push_reg(emit, VTYPE_PYOBJ, REG_RET);
}
STATIC void emit_native_import_star(emit_t *emit) {
DEBUG_printf("import_star\n");
vtype_kind_t vtype_module;
emit_pre_pop_reg(emit, &vtype_module, REG_ARG_1); // arg1 = module
assert(vtype_module == VTYPE_PYOBJ);
emit_call(emit, MP_F_IMPORT_ALL);
emit_post(emit);
}
STATIC void emit_native_load_const_tok(emit_t *emit, mp_token_kind_t tok) {
DEBUG_printf("load_const_tok(tok=%u)\n", tok);
emit_native_pre(emit);
vtype_kind_t vtype;
mp_uint_t val;
if (emit->do_viper_types) {
switch (tok) {
case MP_TOKEN_KW_NONE: vtype = VTYPE_PTR_NONE; val = 0; break;
case MP_TOKEN_KW_FALSE: vtype = VTYPE_BOOL; val = 0; break;
case MP_TOKEN_KW_TRUE: vtype = VTYPE_BOOL; val = 1; break;
default:
assert(tok == MP_TOKEN_ELLIPSIS);
vtype = VTYPE_PYOBJ; val = (mp_uint_t)&mp_const_ellipsis_obj; break;
}
} else {
vtype = VTYPE_PYOBJ;
switch (tok) {
case MP_TOKEN_KW_NONE: val = (mp_uint_t)mp_const_none; break;
case MP_TOKEN_KW_FALSE: val = (mp_uint_t)mp_const_false; break;
case MP_TOKEN_KW_TRUE: val = (mp_uint_t)mp_const_true; break;
default:
assert(tok == MP_TOKEN_ELLIPSIS);
val = (mp_uint_t)&mp_const_ellipsis_obj; break;
}
}
emit_post_push_imm(emit, vtype, val);
}
STATIC void emit_native_load_const_small_int(emit_t *emit, mp_int_t arg) {
DEBUG_printf("load_const_small_int(int=" INT_FMT ")\n", arg);
emit_native_pre(emit);
if (emit->do_viper_types) {
emit_post_push_imm(emit, VTYPE_INT, arg);
} else {
emit_post_push_imm(emit, VTYPE_PYOBJ, (mp_uint_t)MP_OBJ_NEW_SMALL_INT(arg));
}
}
STATIC void emit_native_load_const_str(emit_t *emit, qstr qst) {
emit_native_pre(emit);
// TODO: Eventually we want to be able to work with raw pointers in viper to
// do native array access. For now we just load them as any other object.
/*
if (emit->do_viper_types) {
// load a pointer to the asciiz string?
emit_post_push_imm(emit, VTYPE_PTR, (mp_uint_t)qstr_str(qst));
} else
*/
{
emit_post_push_imm(emit, VTYPE_PYOBJ, (mp_uint_t)MP_OBJ_NEW_QSTR(qst));
}
}
STATIC void emit_native_load_const_obj(emit_t *emit, mp_obj_t obj) {
emit_native_pre(emit);
need_reg_single(emit, REG_RET, 0);
ASM_MOV_ALIGNED_IMM_TO_REG(emit->as, (mp_uint_t)obj, REG_RET);
emit_post_push_reg(emit, VTYPE_PYOBJ, REG_RET);
}
STATIC void emit_native_load_null(emit_t *emit) {
emit_native_pre(emit);
emit_post_push_imm(emit, VTYPE_PYOBJ, 0);
}
STATIC void emit_native_load_fast(emit_t *emit, qstr qst, mp_uint_t local_num) {
DEBUG_printf("load_fast(%s, " UINT_FMT ")\n", qstr_str(qst), local_num);
vtype_kind_t vtype = emit->local_vtype[local_num];
if (vtype == VTYPE_UNBOUND) {
EMIT_NATIVE_VIPER_TYPE_ERROR(emit, "local '%q' used before type known", qst);
}
emit_native_pre(emit);
if (local_num == 0) {
emit_post_push_reg(emit, vtype, REG_LOCAL_1);