py: Add support to save native, viper and asm code to .mpy files.

This commit adds support for saving and loading .mpy files that contain
native code (native, viper and inline-asm).  A lot of the ground work was
already done for this in the form of removing pointers from generated
native code.  The changes here are mainly to link in qstr values to the
native code, and change the format of .mpy files to contain native code
blocks (possibly mixed with bytecode).

A top-level summary:

- @micropython.native, @micropython.viper and @micropython.asm_thumb/
  asm_xtensa are now allowed in .py files when compiling to .mpy, and they
  work transparently to the user.

- Entire .py files can be compiled to native via mpy-cross -X emit=native
  and for the most part the generated .mpy files should work the same as
  their bytecode version.

- The .mpy file format is changed to 1) specify in the header if the file
  contains native code and if so the architecture (eg x86, ARMV7M, Xtensa);
  2) for each function block the kind of code is specified (bytecode,
  native, viper, asm).

- When native code is loaded from a .mpy file the native code must be
  modified (in place) to link qstr values in, just like bytecode (see
  py/persistentcode.c:arch_link_qstr() function).

In addition, this now defines a public, native ABI for dynamically loadable
native code generated by other languages, like C.

1 files changed, 4 insertions, 2 deletions

diff --git a/py/asmthumb.h b/py/asmthumb.h
index 9a44a78ca..c21c23ff7 100644
--- a/py/asmthumb.h
+++ b/py/asmthumb.h
@@ -241,14 +241,14 @@ static inline void asm_thumb_ldrh_rlo_rlo_i5(asm_thumb_t *as, uint rlo_dest, uin
 #define ASM_THUMB_OP_MOVT (0xf2c0)
 
 void asm_thumb_mov_reg_reg(asm_thumb_t *as, uint reg_dest, uint reg_src);
-void asm_thumb_mov_reg_i16(asm_thumb_t *as, uint mov_op, uint reg_dest, int i16_src);
+size_t asm_thumb_mov_reg_i16(asm_thumb_t *as, uint mov_op, uint reg_dest, int i16_src);
 
 // these return true if the destination is in range, false otherwise
 bool asm_thumb_b_n_label(asm_thumb_t *as, uint label);
 bool asm_thumb_bcc_nw_label(asm_thumb_t *as, int cond, uint label, bool wide);
 bool asm_thumb_bl_label(asm_thumb_t *as, uint label);
 
-void asm_thumb_mov_reg_i32(asm_thumb_t *as, uint reg_dest, mp_uint_t i32_src); // convenience
+size_t asm_thumb_mov_reg_i32(asm_thumb_t *as, uint reg_dest, mp_uint_t i32_src); // convenience
 void asm_thumb_mov_reg_i32_optimised(asm_thumb_t *as, uint reg_dest, int i32_src); // convenience
 void asm_thumb_mov_local_reg(asm_thumb_t *as, int local_num_dest, uint rlo_src); // convenience
 void asm_thumb_mov_reg_local(asm_thumb_t *as, uint rlo_dest, int local_num); // convenience
@@ -315,6 +315,8 @@ void asm_thumb_bl_ind(asm_thumb_t *as, uint fun_id, uint reg_temp); // convenien
 
 #define ASM_MOV_LOCAL_REG(as, local_num, reg) asm_thumb_mov_local_reg((as), (local_num), (reg))
 #define ASM_MOV_REG_IMM(as, reg_dest, imm) asm_thumb_mov_reg_i32_optimised((as), (reg_dest), (imm))
+#define ASM_MOV_REG_IMM_FIX_U16(as, reg_dest, imm) asm_thumb_mov_reg_i16((as), ASM_THUMB_OP_MOVW, (reg_dest), (imm))
+#define ASM_MOV_REG_IMM_FIX_WORD(as, reg_dest, imm) asm_thumb_mov_reg_i32((as), (reg_dest), (imm))
 #define ASM_MOV_REG_LOCAL(as, reg_dest, local_num) asm_thumb_mov_reg_local((as), (reg_dest), (local_num))
 #define ASM_MOV_REG_REG(as, reg_dest, reg_src) asm_thumb_mov_reg_reg((as), (reg_dest), (reg_src))
 #define ASM_MOV_REG_LOCAL_ADDR(as, reg_dest, local_num) asm_thumb_mov_reg_local_addr((as), (reg_dest), (local_num))