TonBERRY/micropython
3
0
Fork 0
Code Pull Requests Activity

py/asm*: Support assembling code to jump to a register, and get PC+off.

Browse Source 
Useful for position independent code, and implementing state machines.
This commit is contained in:
Damien George
2018-08-16 13:45:24 +10:00
parent f7d6108d1a
commit 2964b41c28
10 changed files with 122 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

14
py/asmx64.c
View File

@@ -76,6 +76,7 @@
#define OPCODE_TEST_R64_WITH_RM64 (0x85) /* /r */
#define OPCODE_JMP_REL8 (0xeb)
#define OPCODE_JMP_REL32 (0xe9)
#define OPCODE_JMP_RM64 (0xff) /* /4 */
#define OPCODE_JCC_REL8 (0x70) /* | jcc type */
#define OPCODE_JCC_REL32_A (0x0f)
#define OPCODE_JCC_REL32_B (0x80) /* | jcc type */
@@ -481,6 +482,11 @@ void asm_x64_setcc_r8(asm_x64_t *as, int jcc_type, int dest_r8) {
asm_x64_write_byte_3(as, OPCODE_SETCC_RM8_A, OPCODE_SETCC_RM8_B | jcc_type, MODRM_R64(0) | MODRM_RM_REG | MODRM_RM_R64(dest_r8));
}
void asm_x64_jmp_reg(asm_x64_t *as, int src_r64) {
assert(src_r64 < 8);
asm_x64_write_byte_2(as, OPCODE_JMP_RM64, MODRM_R64(4) | MODRM_RM_REG | MODRM_RM_R64(src_r64));
}
STATIC mp_uint_t get_label_dest(asm_x64_t *as, mp_uint_t label) {
assert(label < as->base.max_num_labels);
return as->base.label_offsets[label];
@@ -582,6 +588,14 @@ void asm_x64_mov_local_addr_to_r64(asm_x64_t *as, int local_num, int dest_r64) {
}
}
void asm_x64_mov_reg_pcrel(asm_x64_t *as, int dest_r64, mp_uint_t label) {
assert(dest_r64 < 8);
mp_uint_t dest = get_label_dest(as, label);
mp_int_t rel = dest - (as->base.code_offset + 7);
asm_x64_write_byte_3(as, REX_PREFIX | REX_W, OPCODE_LEA_MEM_TO_R64, MODRM_R64(dest_r64) | MODRM_RM_R64(5));
asm_x64_write_word32(as, rel);
}
/*
void asm_x64_push_local(asm_x64_t *as, int local_num) {
asm_x64_push_disp(as, ASM_X64_REG_RBP, asm_x64_local_offset_from_ebp(as, local_num));