diff options
Diffstat (limited to 'py/asmarm.c')
-rw-r--r-- | py/asmarm.c | 52 |
1 files changed, 33 insertions, 19 deletions
diff --git a/py/asmarm.c b/py/asmarm.c index be50a991b7..15bc73b61e 100644 --- a/py/asmarm.c +++ b/py/asmarm.c @@ -38,8 +38,6 @@ #define REG_TEMP ASM_ARM_REG_R8 -#define SIGNED_FIT24(x) (((x) & 0xff800000) == 0) || (((x) & 0xff000000) == 0xff000000) - // Insert word into instruction flow static void emit(asm_arm_t *as, uint op) { uint8_t *c = mp_asm_base_get_cur_to_write_bytes(&as->base, 4); @@ -347,11 +345,6 @@ void asm_arm_ldr_reg_reg_offset(asm_arm_t *as, uint rd, uint rn, uint byte_offse } } -void asm_arm_ldrh_reg_reg(asm_arm_t *as, uint rd, uint rn) { - // ldrh rd, [rn] - emit_al(as, 0x1d000b0 | (rn << 16) | (rd << 12)); -} - void asm_arm_ldrh_reg_reg_reg(asm_arm_t *as, uint rd, uint rm, uint rn) { // ldrh doesn't support scaled register index emit_al(as, 0x1a00080 | (REG_TEMP << 12) | rn); // mov temp, rn, lsl #1 @@ -370,16 +363,23 @@ void asm_arm_ldrh_reg_reg_offset(asm_arm_t *as, uint rd, uint rn, uint byte_offs } } -void asm_arm_ldrb_reg_reg(asm_arm_t *as, uint rd, uint rn) { - // ldrb rd, [rn] - emit_al(as, 0x5d00000 | (rn << 16) | (rd << 12)); -} - void asm_arm_ldrb_reg_reg_reg(asm_arm_t *as, uint rd, uint rm, uint rn) { // ldrb rd, [rm, rn] emit_al(as, 0x7d00000 | (rm << 16) | (rd << 12) | rn); } +void asm_arm_ldrb_reg_reg_offset(asm_arm_t *as, uint rd, uint rn, uint byte_offset) { + if (byte_offset < 0x1000) { + // ldrb rd, [rn, #off] + emit_al(as, 0x5d00000 | (rn << 16) | (rd << 12) | byte_offset); + } else { + // mov temp, #off + // ldrb rd, [rn, temp] + asm_arm_mov_reg_i32_optimised(as, REG_TEMP, byte_offset); + emit_al(as, 0x7d00000 | (rn << 16) | (rd << 12) | REG_TEMP); + } +} + void asm_arm_ldr_reg_reg_reg(asm_arm_t *as, uint rd, uint rm, uint rn) { // ldr rd, [rm, rn, lsl #2] emit_al(as, 0x7900100 | (rm << 16) | (rd << 12) | rn); @@ -397,14 +397,28 @@ void asm_arm_str_reg_reg_offset(asm_arm_t *as, uint rd, uint rm, uint byte_offse } } -void asm_arm_strh_reg_reg(asm_arm_t *as, uint rd, uint rm) { - // strh rd, [rm] - emit_al(as, 0x1c000b0 | (rm << 16) | (rd << 12)); +void asm_arm_strh_reg_reg_offset(asm_arm_t *as, uint rd, uint rn, uint byte_offset) { + if (byte_offset < 0x100) { + // strh rd, [rn, #off] + emit_al(as, 0x1c000b0 | (rn << 16) | (rd << 12) | ((byte_offset & 0xf0) << 4) | (byte_offset & 0xf)); + } else { + // mov temp, #off + // strh rd, [rn, temp] + asm_arm_mov_reg_i32_optimised(as, REG_TEMP, byte_offset); + emit_al(as, 0x18000b0 | (rn << 16) | (rd << 12) | REG_TEMP); + } } -void asm_arm_strb_reg_reg(asm_arm_t *as, uint rd, uint rm) { - // strb rd, [rm] - emit_al(as, 0x5c00000 | (rm << 16) | (rd << 12)); +void asm_arm_strb_reg_reg_offset(asm_arm_t *as, uint rd, uint rm, uint byte_offset) { + if (byte_offset < 0x1000) { + // strb rd, [rm, #off] + emit_al(as, 0x5c00000 | (rm << 16) | (rd << 12) | byte_offset); + } else { + // mov temp, #off + // strb rd, [rm, temp] + asm_arm_mov_reg_i32_optimised(as, REG_TEMP, byte_offset); + emit_al(as, 0x7c00000 | (rm << 16) | (rd << 12) | REG_TEMP); + } } void asm_arm_str_reg_reg_reg(asm_arm_t *as, uint rd, uint rm, uint rn) { @@ -430,7 +444,7 @@ void asm_arm_bcc_label(asm_arm_t *as, int cond, uint label) { rel -= 8; // account for instruction prefetch, PC is 8 bytes ahead of this instruction rel >>= 2; // in ARM mode the branch target is 32-bit aligned, so the 2 LSB are omitted - if (SIGNED_FIT24(rel)) { + if (MP_FIT_SIGNED(24, rel)) { emit(as, cond | 0xa000000 | (rel & 0xffffff)); } else { printf("asm_arm_bcc: branch does not fit in 24 bits\n"); |