diff options
| -rw-r--r-- | py/asmxtensa.c | 23 |
1 files changed, 19 insertions, 4 deletions
diff --git a/py/asmxtensa.c b/py/asmxtensa.c index fd71dedb1..85a8cfef5 100644 --- a/py/asmxtensa.c +++ b/py/asmxtensa.c @@ -192,12 +192,27 @@ void asm_xtensa_bccz_reg_label(asm_xtensa_t *as, uint cond, uint reg, uint label } void asm_xtensa_bcc_reg_reg_label(asm_xtensa_t *as, uint cond, uint reg1, uint reg2, uint label) { - uint32_t dest = get_label_dest(as, label); - int32_t rel = dest - as->base.code_offset - 4; - if (as->base.pass == MP_ASM_PASS_EMIT && !SIGNED_FIT8(rel)) { + ptrdiff_t rel = 0; + bool can_emit_short_jump = calculate_branch_displacement(as, label, &rel); + + if (can_emit_short_jump && SIGNED_FIT8(rel)) { + // Backwards BCC opcodes with an offset that fits in 8 bits can + // be emitted without any change. + asm_xtensa_op_bcc(as, cond, reg1, reg2, rel); + return; + } + + // Range is effectively extended to 18 bits, as a more complex jump code + // sequence is emitted. + if (as->base.pass == MP_ASM_PASS_EMIT && !SIGNED_FIT18(rel - 6)) { mp_raise_msg_varg(&mp_type_RuntimeError, ET_OUT_OF_RANGE, MP_QSTR_bcc); } - asm_xtensa_op_bcc(as, cond, reg1, reg2, rel); + + // ~BCC skip ; +0 <- Condition is flipped here (EQ -> NE, etc.) + // J addr ; +3 + // skip: ; +6 + asm_xtensa_op_bcc(as, cond ^ 8, reg1, reg2, 6 - 4); + asm_xtensa_op_j(as, rel - 3); } // convenience function; reg_dest must be different from reg_src[12] |