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py: Add ldrex and strex to thumb2 inline assembler. 

These are useful for implementing atomic lock operations.
This commit is contained in:
Damien George 2015-02-12 22:52:42 +00:00
parent 91fc4a9ce1
commit 1bf5a022fe
1 changed files with 17 additions and 0 deletions
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17
py/emitinlinethumb.c
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@ -397,6 +397,14 @@ STATIC void emit_inline_thumb_op(emit_inline_asm_t *emit, qstr op, mp_uint_t n_a
} else if (strcmp(op_str, "strh") == 0) {
op_code = ASM_THUMB_FORMAT_10_STRH;
goto op_format_9_10;
} else if (strcmp(op_str, "ldrex") == 0) {
mp_uint_t r_dest = get_arg_reg(emit, op_str, pn_args[0], 15);
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 r_base = get_arg_reg(emit, op_str, pn_base, 15);
mp_uint_t i8 = get_arg_i(emit, op_str, pn_offset, 0xff) >> 2;
asm_thumb_op32(emit->as, 0xe850 | r_base, 0x0f00 | (r_dest << 12) | i8);
}
} else {
goto unknown_op;
}
@ -422,6 +430,15 @@ STATIC void emit_inline_thumb_op(emit_inline_asm_t *emit, qstr op, mp_uint_t n_a
} else if (strcmp(op_str, "sub") == 0) {
op_code = ASM_THUMB_FORMAT_2_SUB;
goto op_format_2;
} else if (strcmp(op_str, "strex") == 0) {
mp_uint_t r_dest = get_arg_reg(emit, op_str, pn_args[0], 15);
mp_uint_t r_src = get_arg_reg(emit, op_str, pn_args[1], 15);
mp_parse_node_t pn_base, pn_offset;
if (get_arg_addr(emit, op_str, pn_args[2], &pn_base, &pn_offset)) {
mp_uint_t r_base = get_arg_reg(emit, op_str, pn_base, 15);
mp_uint_t i8 = get_arg_i(emit, op_str, pn_offset, 0xff) >> 2;
asm_thumb_op32(emit->as, 0xe840 | r_base, (r_src << 12) | (r_dest << 8) | i8);
}
} else {
goto unknown_op;
}