10000 esp32: support for native code generation by dpgeorge · Pull Request #5082 · micropython/micropython · GitHub
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esp32: support for native code generation #5082

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Merged
merged 7 commits into from
Oct 5, 2019
Merged

esp32: support for native code generation #5082

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4107597
py/emitnative: Add support for archs with windowed registers.
dpgeorge Sep 10, 2019
3504edc
py/emitnative: Add support for using setjmp with native emitter.
dpgeorge Sep 10, 2019
306ec53
py/emitnative: Add support for archs that cannot read executable data.
dpgeorge Sep 10, 2019
f7ddc94
py/asmxtensa: Add support for Xtensa with windowed registers.
dpgeorge Sep 10, 2019
9adedce
py: Add new Xtensa-Windowed arch for native emitter.
dpgeorge Sep 13, 2019
917f027
esp32: Enable native emitter.
dpgeorge Sep 10, 2019
1d21b4e
mpy-cross: Enable Xtensa-Windowed native emitter.
dpgeorge Sep 13, 2019
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5 changes: 4 additions & 1 deletion mpy-cross/main.c
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Expand Up @@ -109,7 +109,7 @@ STATIC int usage(char **argv) {
"-msmall-int-bits=number : set the maximum bits used to encode a small-int\n"
"-mno-unicode : don't support unicode in compiled strings\n"
"-mcache-lookup-bc : cache map lookups in the bytecode\n"
"-march=<arch> : set architecture for native emitter; x86, x64, armv6, armv7m, xtensa\n"
"-march=<arch> : set architecture for native emitter; x86, x64, armv6, armv7m, xtensa, xtensawin\n"
"\n"
"Implementation specific options:\n", argv[0]
);
Expand Down Expand Up @@ -288,6 +288,9 @@ MP_NOINLINE int main_(int argc, char **argv) {
} else if (strcmp(arch, "xtensa") == 0) {
mp_dynamic_compiler.native_arch = MP_NATIVE_ARCH_XTENSA;
mp_dynamic_compiler.nlr_buf_num_regs = MICROPY_NLR_NUM_REGS_XTENSA;
} else if (strcmp(arch, "xtensawin") == 0) {
mp_dynamic_compiler.native_arch = MP_NATIVE_ARCH_XTENSAWIN;
mp_dynamic_compiler.nlr_buf_num_regs = MICROPY_NLR_NUM_REGS_XTENSAWIN;
} else {
return usage(argv);
}
Expand Down
1 change: 1 addition & 0 deletions mpy-cross/mpconfigport.h
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Expand Up @@ -39,6 +39,7 @@
#define MICROPY_EMIT_ARM (1)
#define MICROPY_EMIT_XTENSA (1)
#define MICROPY_EMIT_INLINE_XTENSA (1)
#define MICROPY_EMIT_XTENSAWIN (1)

#define MICROPY_DYNAMIC_COMPILER (1)
#define MICROPY_COMP_CONST_FOLDING (1)
Expand Down
10 changes: 10 additions & 0 deletions ports/esp32/main.c
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Expand Up @@ -172,3 +172,13 @@ void nlr_jump_fail(void *val) {
void mbedtls_debug_set_threshold(int threshold) {
(void)threshold;
}

void *esp_native_code_commit(void *buf, size_t len) {
len = (len + 3) & ~3;
uint32_t *p = heap_caps_malloc(len, MALLOC_CAP_EXEC);
if (p == NULL) {
m_malloc_fail(len);
}
memcpy(p, buf, len);
return p;
}
3 changes: 3 additions & 0 deletions ports/esp32/mpconfigport.h
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Expand Up @@ -20,6 +20,9 @@

// emitters
#define MICROPY_PERSISTENT_CODE_LOAD (1)
#define MICROPY_EMIT_XTENSAWIN (1)
void *esp_native_code_commit(void*, size_t);
#define MP_PLAT_COMMIT_EXEC(buf, len) esp_native_code_commit(buf, len)

// compiler configuration
#define MICROPY_COMP_MODULE_CONST (1)
Expand Down
42 changes: 33 additions & 9 deletions py/asmxtensa.c
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Expand Up @@ -30,14 +30,13 @@
#include "py/mpconfig.h"

// wrapper around everything in this file
#if MICROPY_EMIT_XTENSA || MICROPY_EMIT_INLINE_XTENSA
#if MICROPY_EMIT_XTENSA || MICROPY_EMIT_INLINE_XTENSA || MICROPY_EMIT_XTENSAWIN

#include "py/asmxtensa.h"

#define WORD_SIZE (4)
#define SIGNED_FIT8(x) ((((x) & 0xffffff80) == 0) || (((x) & 0xffffff80) == 0xffffff80))
#define SIGNED_FIT12(x) ((((x) & 0xfffff800) == 0) || (((x) & 0xfffff800) == 0xfffff800))
#define NUM_REGS_SAVED (5)

void asm_xtensa_end_pass(asm_xtensa_t *as) {
as->num_const = as->cur_const;
Expand Down Expand Up @@ -69,7 +68,7 @@ void asm_xtensa_entry(asm_xtensa_t *as, int num_locals) {
as->const_table = (uint32_t*)mp_asm_base_get_cur_to_write_bytes(&as->base, as->num_const * 4);

// adjust the stack-pointer to store a0, a12, a13, a14, a15 and locals, 16-byte aligned
as->stack_adjust = (((NUM_REGS_SAVED + num_locals) * WORD_SIZE) + 15) & ~15;
as->stack_adjust = (((ASM_XTENSA_NUM_REGS_SAVED + num_locals) * WORD_SIZE) + 15) & ~15;
if (SIGNED_FIT8(-as->stack_adjust)) {
asm_xtensa_op_addi(as, ASM_XTENSA_REG_A1, ASM_XTENSA_REG_A1, -as->stack_adjust);
} else {
Expand All @@ -79,14 +78,14 @@ void asm_xtensa_entry(asm_xtensa_t *as, int num_locals) {

// save return value (a0) and callee-save registers (a12, a13, a14, a15)
asm_xtensa_op_s32i_n(as, ASM_XTENSA_REG_A0, ASM_XTENSA_REG_A1, 0);
for (int i = 1; i < NUM_REGS_SAVED; ++i) {
for (int i = 1; i < ASM_XTENSA_NUM_REGS_SAVED; ++i) {
asm_xtensa_op_s32i_n(as, ASM_XTENSA_REG_A11 + i, ASM_XTENSA_REG_A1, i);
}
}

void asm_xtensa_exit(asm_xtensa_t *as) {
// restore registers
for (int i = NUM_REGS_SAVED - 1; i >= 1; --i) {
for (int i = ASM_XTENSA_NUM_REGS_SAVED - 1; i >= 1; --i) {
asm_xtensa_op_l32i_n(as, ASM_XTENSA_REG_A11 + i, ASM_XTENSA_REG_A1, i);
}
asm_xtensa_op_l32i_n(as, ASM_XTENSA_REG_A0, ASM_XTENSA_REG_A1, 0);
Expand All @@ -102,6 +101,22 @@ void asm_xtensa_exit(asm_xtensa_t *as) {
asm_xtensa_op_ret_n(as);
}

void asm_xtensa_entry_win(asm_xtensa_t *as, int num_locals) {
// jump over the constants
asm_xtensa_op_j(as, as->num_const * WORD_SIZE + 4 - 4);
mp_asm_base_get_cur_to_write_bytes(&as->base, 1); // padding/alignment byte
as->const_table = (uint32_t*)mp_asm_base_get_cur_to_write_bytes(&as->base, as->num_const * 4);

as->stack_adjust = 32 + ((((ASM_XTENSA_NUM_REGS_SAVED_WIN + num_locals) * WORD_SIZE) + 15) & ~15);
asm_xtensa_op_entry(as, ASM_XTENSA_REG_A1, as->stack_adjust);
asm_xtensa_op_s32i_n(as, ASM_XTENSA_REG_A0, ASM_XTENSA_REG_A1, 0);
}

void asm_xtensa_exit_win(asm_xtensa_t *as) {
asm_xtensa_op_l32i_n(as, ASM_XTENSA_REG_A0, ASM_XTENSA_REG_A1, 0);
asm_xtensa_op_retw_n(as);
}

STATIC uint32_t get_label_dest(asm_xtensa_t *as, uint label) {
assert(label < as->base.max_num_labels);
return as->base.label_offsets[label];
Expand Down Expand Up @@ -178,15 +193,15 @@ void asm_xtensa_mov_reg_i32_optimised(asm_xtensa_t *as, uint reg_dest, uint32_t
}

void asm_xtensa_mov_local_reg(asm_xtensa_t *as, int local_num, uint reg_src) {
asm_xtensa_op_s32i(as, reg_src, ASM_XTENSA_REG_A1, NUM_REGS_SAVED + local_num);
asm_xtensa_op_s32i(as, reg_src, ASM_XTENSA_REG_A1, local_num);
}

void asm_xtensa_mov_reg_local(asm_xtensa_t *as, uint reg_dest, int local_num) {
asm_xtensa_op_l32i(as, reg_dest, ASM_XTENSA_REG_A1, NUM_REGS_SAVED + local_num);
asm_xtensa_op_l32i(as, reg_dest, ASM_XTENSA_REG_A1, local_num);
}

void asm_xtensa_mov_reg_local_addr(asm_xtensa_t *as, uint reg_dest, int local_num) {
uint off = (NUM_REGS_SAVED + local_num) * WORD_SIZE;
uint off = local_num * WORD_SIZE;
if (SIGNED_FIT8(off)) {
asm_xtensa_op_addi(as, reg_dest, ASM_XTENSA_REG_A1, off);
} else {
Expand Down Expand Up @@ -226,4 +241,13 @@ void asm_xtensa_call_ind(asm_xtensa_t *as, uint idx) {
asm_xtensa_op_callx0(as, ASM_XTENSA_REG_A0);
}

#endif // MICROPY_EMIT_XTENSA || MICROPY_EMIT_INLINE_XTENSA
void asm_xtensa_call_ind_win(asm_xtensa_t *as, uint idx) {
if (idx < 16) {
asm_xtensa_op_l32i_n(as, ASM_XTENSA_REG_A8, ASM_XTENSA_REG_FUN_TABLE_WIN, idx);
} else {
asm_xtensa_op_l32i(as, ASM_XTENSA_REG_A8, ASM_XTENSA_REG_FUN_TABLE_WIN, idx);
}
asm_xtensa_op_callx8(as, ASM_XTENSA_REG_A8);
}

#endif // MICROPY_EMIT_XTENSA || MICROPY_EMIT_INLINE_XTENSA || MICROPY_EMIT_XTENSAWIN
80 changes: 74 additions & 6 deletions py/asmxtensa.h
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Expand Up @@ -37,6 +37,16 @@
// callee save: a1, a12, a13, a14, a15
// caller save: a3

// With windowed registers, size 8:
// - a0: return PC
// - a1: stack pointer, full descending, aligned to 16 bytes
// - a2-a7: incoming args, and essentially callee save
// - a2: return value
// - a8-a15: caller save temporaries
// - a10-a15: input args to called function
// - a10: return value of called function
// note: a0-a7 are saved automatically via window shift of called function

#define ASM_XTENSA_REG_A0 (0)
#define ASM_XTENSA_REG_A1 (1)
#define ASM_XTENSA_REG_A2 (2)
Expand Down Expand Up @@ -96,6 +106,10 @@
#define ASM_XTENSA_ENCODE_RI7(op0, s, imm7) \
((((imm7) & 0xf) << 12) | ((s) << 8) | ((imm7) & 0x70) | (op0))

// Number of registers saved on the stack upon entry to function
#define ASM_XTENSA_NUM_REGS_SAVED (5)
#define ASM_XTENSA_NUM_REGS_SAVED_WIN (1)

typedef struct _asm_xtensa_t {
mp_asm_base_t base;
uint32_t cur_const;
Expand All @@ -109,11 +123,18 @@ void asm_xtensa_end_pass(asm_xtensa_t *as);
void asm_xtensa_entry(asm_xtensa_t *as, int num_locals);
void asm_xtensa_exit(asm_xtensa_t *as);

void asm_xtensa_entry_win(asm_xtensa_t *as, int num_locals);
void asm_xtensa_exit_win(asm_xtensa_t *as);

void asm_xtensa_op16(asm_xtensa_t *as, uint16_t op);
void asm_xtensa_op24(asm_xtensa_t *as, uint32_t op);

// raw instructions

static inline void asm_xtensa_op_entry(asm_xtensa_t *as, uint reg_src, int32_t num_bytes) {
asm_xtensa_op24(as, ASM_XTENSA_ENCODE_BRI12(6, reg_src, 0, 3, (num_bytes / 8) & 0xfff));
}

static inline void asm_xtensa_op_add_n(asm_xtensa_t *as, uint reg_dest, uint reg_src_a, uint reg_src_b) {
asm_xtensa_op16(as, ASM_XTENSA_ENCODE_RRRN(10, reg_dest, reg_src_a, reg_src_b));
}
Expand Down Expand Up @@ -142,6 +163,10 @@ static inline void asm_xtensa_op_callx0(asm_xtensa_t *as, uint reg) {
asm_xtensa_op24(as, ASM_XTENSA_ENCODE_CALLX(0, 0, 0, 0, reg, 3, 0));
}

static inline void asm_xtensa_op_callx8(asm_xtensa_t *as, uint reg) {
asm_xtensa_op24(as, ASM_XTENSA_ENCODE_CALLX(0, 0, 0, 0, reg, 3, 2));
}

static inline void asm_xtensa_op_j(asm_xtensa_t *as, int32_t rel18) {
asm_xtensa_op24(as, ASM_XTENSA_ENCODE_CALL(6, 0, rel18 & 0x3ffff));
}
Expand Down Expand Up @@ -194,6 +219,10 @@ static inline void asm_xtensa_op_ret_n(asm_xtensa_t *as) {
asm_xtensa_op16(as, ASM_XTENSA_ENCODE_RRRN(13, 15, 0, 0));
}

static inline void asm_xtensa_op_retw_n(asm_xtensa_t *as) {
asm_xtensa_op16(as, ASM_XTENSA_ENCODE_RRRN(13, 15, 0, 1));
}

static inline void asm_xtensa_op_s8i(asm_xtensa_t *as, uint reg_src, uint reg_base, uint byte_offset) {
asm_xtensa_op24(as, ASM_XTENSA_ENCODE_RRI8(2, 4, reg_base, reg_src, byte_offset & 0xff));
}
Expand Down Expand Up @@ -246,9 +275,11 @@ void asm_xtensa_mov_reg_local(asm_xtensa_t *as, uint reg_dest, int local_num);
void asm_xtensa_mov_reg_local_addr(asm_xtensa_t *as, uint reg_dest, int local_num);
void asm_xtensa_mov_reg_pcrel(asm_xtensa_t *as, uint reg_dest, uint label);
void asm_xtensa_call_ind(asm_xtensa_t *as, uint idx);
void asm_xtensa_call_ind_win(asm_xtensa_t *as, uint idx);

// Holds a pointer to mp_fun_table
#define ASM_XTENSA_REG_FUN_TABLE ASM_XTENSA_REG_A15
#define ASM_XTENSA_REG_FUN_TABLE_WIN ASM_XTENSA_REG_A7

#if GENERIC_ASM_API

Expand All @@ -257,6 +288,9 @@ void asm_xtensa_call_ind(asm_xtensa_t *as, uint idx);

#define ASM_WORD_SIZE (4)

#if !GENERIC_ASM_API_WIN
// Configuration for non-windowed calls

#define REG_RET ASM_XTENSA_REG_A2
#define REG_ARG_1 ASM_XTENSA_REG_A2
#define REG_ARG_2 ASM_XTENSA_REG_A3
Expand All @@ -273,12 +307,47 @@ void asm_xtensa_call_ind(asm_xtensa_t *as, uint idx);
#define REG_LOCAL_3 ASM_XTENSA_REG_A14
#define REG_LOCAL_NUM (3)

#define ASM_NUM_REGS_SAVED ASM_XTENSA_NUM_REGS_SAVED
#define REG_FUN_TABLE ASM_XTENSA_REG_FUN_TABLE

#define ASM_ENTRY(as, nlocal) asm_xtensa_entry((as), (nlocal))
#define ASM_EXIT(as) asm_xtensa_exit((as))
#define ASM_CALL_IND(as, idx) asm_xtensa_call_ind((as), (idx))

#else
// Configuration for windowed calls with window size 8

#define REG_PARENT_RET ASM_XTENSA_REG_A2
#define REG_PARENT_ARG_1 ASM_XTENSA_REG_A2
#define REG_PARENT_ARG_2 ASM_XTENSA_REG_A3
#define REG_PARENT_ARG_3 ASM_XTENSA_REG_A4
#define REG_PARENT_ARG_4 ASM_XTENSA_REG_A5
#define REG_RET ASM_XTENSA_REG_A10
#define REG_ARG_1 ASM_XTENSA_REG_A10
#define REG_ARG_2 ASM_XTENSA_REG_A11
#define REG_ARG_3 ASM_XTENSA_REG_A12
#define REG_ARG_4 ASM_XTENSA_REG_A13

#define REG_TEMP0 ASM_XTENSA_REG_A10
#define REG_TEMP1 ASM_XTENSA_REG_A11
#define REG_TEMP2 ASM_XTENSA_REG_A12

#define REG_LOCAL_1 ASM_XTENSA_REG_A4
#define REG_LOCAL_2 ASM_XTENSA_REG_A5
#define REG_LOCAL_3 ASM_XTENSA_REG_A6
#define REG_LOCAL_NUM (3)

#define ASM_NUM_REGS_SAVED ASM_XTENSA_NUM_REGS_SAVED_WIN
#define REG_FUN_TABLE ASM_XTENSA_REG_FUN_TABLE_WIN

#define ASM_ENTRY(as, nlocal) asm_xtensa_entry_win((as), (nlocal))
#define ASM_EXIT(as) asm_xtensa_exit_win((as))
#define ASM_CALL_IND(as, idx) asm_xtensa_call_ind_win((as), (idx))

#endif

#define ASM_T asm_xtensa_t
#define ASM_END_PASS asm_xtensa_end_pass
#define ASM_ENTRY asm_xtensa_entry
#define ASM_EXIT asm_xtensa_exit

#define ASM_JUMP asm_xtensa_j_label
#define ASM_JUMP_IF_REG_ZERO(as, reg, label, bool_test) \
Expand All @@ -288,15 +357,14 @@ void asm_xtensa_call_ind(asm_xtensa_t *as, uint idx);
#define ASM_JUMP_IF_REG_EQ(as, reg1, reg2, label) \
asm_xtensa_bcc_reg_reg_label(as, ASM_XTENSA_CC_EQ, reg1, reg2, label)
#define ASM_JUMP_REG(as, reg) asm_xtensa_op_jx((as), (reg))
#define ASM_CALL_IND(as, idx) asm_xtensa_call_ind((as), (idx))

#define ASM_MOV_LOCAL_REG(as, local_num, reg_src) asm_xtensa_mov_local_reg((as), (local_num), (reg_src))
#define ASM_MOV_LOCAL_REG(as, local_num, reg_src) asm_xtensa_mov_local_reg((as), ASM_NUM_REGS_SAVED + (local_num), (reg_src))
#define ASM_MOV_REG_IMM(as, reg_dest, imm) asm_xtensa_mov_reg_i32_optimised((as), (reg_dest), (imm))
#define ASM_MOV_REG_IMM_FIX_U16(as, reg_dest, imm) asm_xtensa_mov_reg_i32((as), (reg_dest), (imm))
#define ASM_MOV_REG_IMM_FIX_WORD(as, reg_dest, imm) asm_xtensa_mov_reg_i32((as), (reg_dest), (imm))
#define ASM_MOV_REG_LOCAL(as, reg_dest, local_num) asm_xtensa_mov_reg_local((as), (reg_dest), (local_num))
#define ASM_MOV_REG_LOCAL(as, reg_dest, local_num) asm_xtensa_mov_reg_local((as), (reg_dest), ASM_NUM_REGS_SAVED + (local_num))
#define ASM_MOV_REG_REG(as, reg_dest, reg_src) asm_xtensa_op_mov_n((as), (reg_dest), (reg_src))
#define ASM_MOV_REG_LOCAL_ADDR(as, reg_dest, local_num) asm_xtensa_mov_reg_local_addr((as), (reg_dest), (local_num))
#define ASM_MOV_REG_LOCAL_ADDR(as, reg_dest, local_num) asm_xtensa_mov_reg_local_addr((as), (reg_dest), ASM_NUM_REGS_SAVED + (local_num))
#define ASM_MOV_REG_PCREL(as, reg_dest, label) asm_xtensa_mov_reg_pcrel((as), (reg_dest), (label))

#define ASM_LSL_REG_REG(as, reg_dest, reg_shift) \
Expand Down
4 changes: 4 additions & 0 deletions py/compile.c
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Expand Up @@ -95,6 +95,7 @@ STATIC const emit_method_table_t *emit_native_table[] = {
&emit_native_thumb_method_table,
&emit_native_thumb_method_table,
&emit_native_xtensa_method_table,
&emit_native_xtensawin_method_table,
};

#elif MICROPY_EMIT_NATIVE
Expand All @@ -109,6 +110,8 @@ STATIC const emit_method_table_t *emit_native_table[] = {
#define NATIVE_EMITTER(f) emit_native_arm_##f
#elif MICROPY_EMIT_XTENSA
#define NATIVE_EMITTER(f) emit_native_xtensa_##f
#elif MICROPY_EMIT_XTENSAWIN
#define NATIVE_EMITTER(f) emit_native_xtensawin_##f
#else
#error "unknown native emitter"
#endif
Expand All @@ -131,6 +134,7 @@ STATIC const emit_inline_asm_method_table_t *emit_asm_table[] = {
&emit_inline_thumb_method_table,
&emit_inline_thumb_method_table,
&emit_inline_xtensa_method_table,
NULL,
};

#elif MICROPY_EMIT_INLINE_ASM
Expand Down
3 changes: 3 additions & 0 deletions py/emit.h
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Expand Up @@ -174,6 +174,7 @@ extern const emit_method_table_t emit_native_x86_method_table;
extern const emit_method_table_t emit_native_thumb_method_table;
extern const emit_method_table_t emit_native_arm_method_table;
extern const emit_method_table_t emit_native_xtensa_method_table;
extern const emit_method_table_t emit_native_xtensawin_method_table;

extern const mp_emit_method_table_id_ops_t mp_emit_bc_method_table_load_id_ops;
extern const mp_emit_method_table_id_ops_t mp_emit_bc_method_table_store_id_ops;
Expand All @@ -185,6 +186,7 @@ emit_t *emit_native_x86_new(mp_obj_t *error_slot, uint *label_slot, mp_uint_t ma
emit_t *emit_native_thumb_new(mp_obj_t *error_slot, uint *label_slot, mp_uint_t max_num_labels);
emit_t *emit_native_arm_new(mp_obj_t *error_slot, uint *label_slot, mp_uint_t max_num_labels);
emit_t *emit_native_xtensa_new(mp_obj_t *error_slot, uint *label_slot, mp_uint_t max_num_labels);
emit_t *emit_native_xtensawin_new(mp_obj_t *error_slot, uint *label_slot, mp_uint_t max_num_labels);

void emit_bc_set_max_num_labels(emit_t* emit, mp_uint_t max_num_labels);

Expand All @@ -194,6 +196,7 @@ void emit_native_x86_free(emit_t *emit);
void emit_native_thumb_free(emit_t *emit);
void emit_native_arm_free(emit_t *emit);
void emit_native_xtensa_free(emit_t *emit);
void emit_native_xtensawin_free(emit_t *emit);

void mp_emit_bc_start_pass(emit_t *emit, pass_kind_t pass, scope_t *scope);
void mp_emit_bc_end_pass(emit_t *emit);
Expand Down
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