py/inlinethumb: Support for core floating point instructions.

Adds support for the following Thumb2 VFP instructions, via the option
MICROPY_EMIT_INLINE_THUMB_FLOAT:

vcmp
vsqrt
vneg
vcvt_f32_to_s32
vcvt_s32_to_f32
vmrs
vmov
vldr
vstr
vadd
vsub
vmul
vdiv
This commit is contained in:
= 2015-04-14 13:14:57 +01:00 committed by Damien George
parent d8cbbcaa9d
commit 5008972fef
12 changed files with 219 additions and 0 deletions

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@ -196,6 +196,35 @@ STATIC mp_uint_t get_arg_reg(emit_inline_asm_t *emit, const char *op, mp_parse_n
return 0;
}
#if MICROPY_EMIT_INLINE_THUMB_FLOAT
STATIC mp_uint_t get_arg_vfpreg(emit_inline_asm_t *emit, const char *op, mp_parse_node_t pn) {
const char *reg_str = get_arg_str(pn);
if (reg_str[0] == 's' && reg_str[1] != '\0') {
mp_uint_t regno = 0;
for (++reg_str; *reg_str; ++reg_str) {
mp_uint_t v = *reg_str;
if (!('0' <= v && v <= '9')) {
goto malformed;
}
regno = 10 * regno + v - '0';
}
if (regno > 31) {
emit_inline_thumb_error_exc(emit,
mp_obj_new_exception_msg_varg(&mp_type_SyntaxError,
"'%s' expects at most r%d", op, 31));
return 0;
} else {
return regno;
}
}
malformed:
emit_inline_thumb_error_exc(emit,
mp_obj_new_exception_msg_varg(&mp_type_SyntaxError,
"'%s' expects an FPU register", op));
return 0;
}
#endif
STATIC mp_uint_t get_arg_reglist(emit_inline_asm_t *emit, const char *op, mp_parse_node_t pn) {
// a register list looks like {r0, r1, r2} and is parsed as a Python set
@ -352,6 +381,17 @@ STATIC const format_9_10_op_t format_9_10_op_table[] = {
};
#undef X
#if MICROPY_EMIT_INLINE_THUMB_FLOAT
// actual opcodes are: 0xee00 | op.hi_nibble, 0x0a00 | op.lo_nibble
typedef struct _format_vfp_op_t { byte op; char name[3]; } format_vfp_op_t;
STATIC const format_vfp_op_t format_vfp_op_table[] = {
{ 0x30, "add" },
{ 0x34, "sub" },
{ 0x20, "mul" },
{ 0x80, "div" },
};
#endif
STATIC void emit_inline_thumb_op(emit_inline_asm_t *emit, qstr op, mp_uint_t n_args, mp_parse_node_t *pn_args) {
// TODO perhaps make two tables:
// one_args =
@ -366,6 +406,102 @@ STATIC void emit_inline_thumb_op(emit_inline_asm_t *emit, qstr op, mp_uint_t n_a
mp_uint_t op_len;
const char *op_str = (const char*)qstr_data(op, &op_len);
#if MICROPY_EMIT_INLINE_THUMB_FLOAT
if (op_str[0] == 'v') {
// floating point operations
if (n_args == 2) {
mp_uint_t op_code = 0x0ac0, op_code_hi;
if (strcmp(op_str, "vcmp") == 0) {
op_code_hi = 0xeeb4;
op_vfp_twoargs:;
mp_uint_t vd = get_arg_vfpreg(emit, op_str, pn_args[0]);
mp_uint_t vm = get_arg_vfpreg(emit, op_str, pn_args[1]);
asm_thumb_op32(emit->as,
op_code_hi | ((vd & 1) << 6),
op_code | ((vd & 0x1e) << 11) | ((vm & 1) << 5) | (vm & 0x1e) >> 1);
} else if (strcmp(op_str, "vsqrt") == 0) {
op_code_hi = 0xeeb1;
goto op_vfp_twoargs;
} else if (strcmp(op_str, "vneg") == 0) {
op_code_hi = 0xeeb1;
op_code = 0x0a40;
goto op_vfp_twoargs;
} else if (strcmp(op_str, "vcvt_f32_s32") == 0) {
op_code_hi = 0xeeb8; // int to float
goto op_vfp_twoargs;
} else if (strcmp(op_str, "vcvt_s32_f32") == 0) {
op_code_hi = 0xeebd; // float to int
goto op_vfp_twoargs;
} else if (strcmp(op_str, "vmrs") == 0) {
mp_uint_t reg_dest;
const char *reg_str0 = get_arg_str(pn_args[0]);
if (strcmp(reg_str0, "APSR_nzcv") == 0) {
reg_dest = 15;
} else {
reg_dest = get_arg_reg(emit, op_str, pn_args[0], 15);
}
const char *reg_str1 = get_arg_str(pn_args[1]);
if (strcmp(reg_str1, "FPSCR") == 0) {
// FP status to ARM reg
asm_thumb_op32(emit->as, 0xeef1, 0x0a10 | (reg_dest << 12));
} else {
goto unknown_op;
}
} else if (strcmp(op_str, "vmov") == 0) {
op_code_hi = 0xee00;
mp_uint_t r_arm, vm;
const char *reg_str = get_arg_str(pn_args[0]);
if (reg_str[0] == 'r') {
r_arm = get_arg_reg(emit, op_str, pn_args[0], 15);
vm = get_arg_vfpreg(emit, op_str, pn_args[1]);
op_code_hi |= 0x10;
} else {
vm = get_arg_vfpreg(emit, op_str, pn_args[0]);
r_arm = get_arg_reg(emit, op_str, pn_args[1], 15);
}
asm_thumb_op32(emit->as,
op_code_hi | ((vm & 0x1e) >> 1),
0x0a10 | (r_arm << 12) | ((vm & 1) << 7));
} else if (strcmp(op_str, "vldr") == 0) {
op_code_hi = 0xed90;
op_vldr_vstr:;
mp_uint_t vd = get_arg_vfpreg(emit, op_str, pn_args[0]);
mp_parse_node_t pn_base, pn_offset;
if (get_arg_addr(emit, op_str, pn_args[1], &pn_base, &pn_offset)) {
mp_uint_t rlo_base = get_arg_reg(emit, op_str, pn_base, 7);
mp_uint_t i8;
i8 = get_arg_i(emit, op_str, pn_offset, 0xff);
asm_thumb_op32(emit->as,
op_code_hi | rlo_base | ((vd & 1) << 6),
0x0a00 | ((vd & 0x1e) << 11) | i8);
}
} else if (strcmp(op_str, "vstr") == 0) {
op_code_hi = 0xed80;
goto op_vldr_vstr;
} else {
goto unknown_op;
}
} else if (n_args == 3) {
// search table for arith ops
for (mp_uint_t i = 0; i < MP_ARRAY_SIZE(format_vfp_op_table); i++) {
if (strncmp(op_str + 1, format_vfp_op_table[i].name, 3) == 0 && op_str[4] == '\0') {
mp_uint_t op_code_hi = 0xee00 | (format_vfp_op_table[i].op & 0xf0);
mp_uint_t op_code = 0x0a00 | ((format_vfp_op_table[i].op & 0x0f) << 4);
mp_uint_t vd = get_arg_vfpreg(emit, op_str, pn_args[0]);
mp_uint_t vn = get_arg_vfpreg(emit, op_str, pn_args[1]);
mp_uint_t vm = get_arg_vfpreg(emit, op_str, pn_args[2]);
asm_thumb_op32(emit->as,
op_code_hi | ((vd & 1) << 6) | (vn >> 1),
op_code | (vm >> 1) | ((vm & 1) << 5) | ((vd & 0x1e) << 11) | ((vn & 1) << 7));
return;
}
}
goto unknown_op;
} else {
goto unknown_op;
}
} else
#endif
if (n_args == 0) {
if (strcmp(op_str, "nop") == 0) {
asm_thumb_op16(emit->as, ASM_THUMB_OP_NOP);

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@ -186,6 +186,11 @@
#define MICROPY_EMIT_INLINE_THUMB (0)
#endif
// Whether to enable float support in the Thumb2 inline assembler
#ifndef MICROPY_EMIT_INLINE_THUMB_FLOAT
#define MICROPY_EMIT_INLINE_THUMB_FLOAT (1)
#endif
// Whether to emit ARM native code
#ifndef MICROPY_EMIT_ARM
#define MICROPY_EMIT_ARM (0)

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@ -0,0 +1,15 @@
@micropython.asm_thumb # r0 = r0+r1-r2
def add_sub(r0, r1, r2):
vmov(s0, r0)
vcvt_f32_s32(s0, s0)
vmov(s1, r1)
vcvt_f32_s32(s1, s1)
vmov(s2, r2)
vcvt_f32_s32(s2, s2)
vadd(s0, s0, s1)
vsub(s0, s0, s2)
vcvt_s32_f32(s31, s0)
vmov(r0, s31)
print(add_sub(100, 20, 30))

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@ -0,0 +1 @@
90

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@ -0,0 +1,14 @@
@micropython.asm_thumb # test vcmp, vmrs
def f(r0, r1):
vmov(s0, r0)
vcvt_f32_s32(s0, s0)
vmov(s1, r1)
vcvt_f32_s32(s1, s1)
vcmp(s1, s0)
vmrs(r0, FPSCR)
mov(r1, 28)
lsr(r0, r1)
print(f(0,1))
print(f(1,1))
print(f(1,0))

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@ -0,0 +1,3 @@
2
6
8

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@ -0,0 +1,12 @@
import array
@micropython.asm_thumb # test vldr, vstr
def arrayadd(r0):
vldr(s0, [r0, 0])
vldr(s1, [r0, 1])
vadd(s2, s0, s1)
vstr(s2, [r0, 2])
z = array.array("f", [2, 4, 10])
arrayadd(z)
print(z[2])

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@ -0,0 +1 @@
6.0

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@ -0,0 +1,15 @@
@micropython.asm_thumb # r0 = (int)(r0*r1/r2)
def muldiv(r0, r1, r2):
vmov(s0, r0)
vcvt_f32_s32(s0, s0)
vmov(s1, r1)
vcvt_f32_s32(s1, s1)
vmov(s2, r2)
vcvt_f32_s32(s2, s2)
vmul(s7, s0, s1)
vdiv(s8, s7, s2)
vcvt_s32_f32(s31, s8)
vmov(r0, s31)
print(muldiv(100, 10, 50))

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@ -0,0 +1 @@
20

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@ -0,0 +1,15 @@
# test vsqrt, vneg
@micropython.asm_thumb # r0 = -(int)(sqrt(r0)*r1)
def sqrt_test(r0, r1):
vmov(s1, r0)
vcvt_f32_s32(s1, s1)
vsqrt(s1, s1)
vmov(s2, r1)
vcvt_f32_s32(s2, s2)
vmul(s0, s1, s2)
vneg(s7, s0)
vcvt_s32_f32(s31, s7)
vmov(r0, s31)
print(sqrt_test(256, 10))

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@ -0,0 +1 @@
-160