On 2026-01-29 19:57, Ilya Leoshkevich wrote:
DIVIDE TO INTEGER computes floating point remainder and is used by
LuaJIT, so add it to QEMU.
Put the main logic into fpu/, because it is way more convenient to
operate on FloatParts than to convert floats back-and-forth.
Signed-off-by: Ilya Leoshkevich <[email protected]>
---
fpu/softfloat.c | 144 +++++++++++++++++++++++++++++++
include/fpu/softfloat.h | 11 +++
target/s390x/helper.h | 1 +
target/s390x/tcg/fpu_helper.c | 56 ++++++++++++
target/s390x/tcg/insn-data.h.inc | 5 +-
target/s390x/tcg/translate.c | 26 ++++++
6 files changed, 242 insertions(+), 1 deletion(-)
I've taken a fresh look and I think I can improve one small thing.
I will change this alongside other feedback (if any) in v4.
[...]
+
+ /*
+ * Final quotient is rounded using final-quotient-rounding
method, and
+ * partial quotient is rounded toward zero.
+ *
+ * Rounding of partial quotient may be inexact. This is the
whole point
+ * of distinguishing partial quotients, so ignore the
exception.
+ */
+ *n = *q;
+ saved_flags = status->float_exception_flags;
+ parts_round_to_int(n,
+ is_q_smallish ?
final_quotient_rounding_mode :
+ float_round_to_zero,
+ 0, status, fmt);
+ float_exception_flags = saved_flags;
saved_flags can probably be eliminated; I can assign directly to
float_exception_flags.
I think I can also use parts_round_to_int_normal(), because all the
other cases are taken care of above.
[...]
