[PATCH v3 2/4] sim: Factor out NaN handling in floating point operations

Dragan Mladjenovic
2022-01-11T21:25:12Z

From: Faraz Shahbazker <fshahbazker@wavecomp.com>

2022-01-10 Faraz Shahbazker <fshahbazker@wavecomp.com>

sim/common/ChangeLog:
* sim-fpu.c (sim_fpu_op_nan): New.
(sim_fpu_add): Factor out NaN operand handling with
a call to sim_fpu_op_nan.
(sim_fpu_sub, sim_fpu_mul, sim_fpu_div): Likewise.
(sim_fpu_rem, sim_fpu_max, sim_fpu_min): Likewise.
* sim-fpu.h (sim_fpu_op_nan): New declaration.
---
sim/common/sim-fpu.c | 189 +++++++------------------------------------
sim/common/sim-fpu.h | 7 ++
2 files changed, 38 insertions(+), 158 deletions(-)

Changes from v2: Fix Werror failures.

diff --git a/sim/common/sim-fpu.c b/sim/common/sim-fpu.c
index 13af3eb7477..9e6abf01391 100644
--- a/sim/common/sim-fpu.c
+++ b/sim/common/sim-fpu.c
@@ -986,7 +986,24 @@ sim_fpu_round_64 (sim_fpu *f,
return do_round (f, 1, round, denorm);
}

+/* NaN handling for binary operations. */

+INLINE_SIM_FPU (int)
+sim_fpu_op_nan (sim_fpu *f, const sim_fpu *l, const sim_fpu *r)
+{
+ if (sim_fpu_is_snan (l) || sim_fpu_is_snan (r))
+ {
+ *f = sim_fpu_is_snan (l) ? *l : *r;
+ f->class = sim_fpu_class_qnan;
+ return sim_fpu_status_invalid_snan;
+ }
+ ASSERT (sim_fpu_is_nan (l) || sim_fpu_is_nan (r));
+ if (sim_fpu_is_qnan (l))
+ *f = *l;
+ else /* if (sim_fpu_is_qnan (r)) */
+ *f = *r;
+ return 0;
+}

/* Arithmetic ops */

@@ -995,28 +1012,8 @@ sim_fpu_add (sim_fpu *f,
const sim_fpu *l,
const sim_fpu *r)
{
- if (sim_fpu_is_snan (l))
- {
- *f = *l;
- f->class = sim_fpu_class_qnan;
- return sim_fpu_status_invalid_snan;
- }
- if (sim_fpu_is_snan (r))
- {
- *f = *r;
- f->class = sim_fpu_class_qnan;
- return sim_fpu_status_invalid_snan;
- }
- if (sim_fpu_is_qnan (l))
- {
- *f = *l;
- return 0;
- }
- if (sim_fpu_is_qnan (r))
- {
- *f = *r;
- return 0;
- }
+ if (sim_fpu_is_nan (l) || sim_fpu_is_nan (r))
+ return sim_fpu_op_nan (f, l, r);
if (sim_fpu_is_infinity (l))
{
if (sim_fpu_is_infinity (r)
@@ -1144,28 +1141,8 @@ sim_fpu_sub (sim_fpu *f,
const sim_fpu *l,
const sim_fpu *r)
{
- if (sim_fpu_is_snan (l))
- {
- *f = *l;
- f->class = sim_fpu_class_qnan;
- return sim_fpu_status_invalid_snan;
- }
- if (sim_fpu_is_snan (r))
- {
- *f = *r;
- f->class = sim_fpu_class_qnan;
- return sim_fpu_status_invalid_snan;
- }
- if (sim_fpu_is_qnan (l))
- {
- *f = *l;
- return 0;
- }
- if (sim_fpu_is_qnan (r))
- {
- *f = *r;
- return 0;
- }
+ if (sim_fpu_is_nan (l) || sim_fpu_is_nan (r))
+ return sim_fpu_op_nan (f, l, r);
if (sim_fpu_is_infinity (l))
{
if (sim_fpu_is_infinity (r)
@@ -1298,28 +1275,8 @@ sim_fpu_mul (sim_fpu *f,
const sim_fpu *l,
const sim_fpu *r)
{
- if (sim_fpu_is_snan (l))
- {
- *f = *l;
- f->class = sim_fpu_class_qnan;
- return sim_fpu_status_invalid_snan;
- }
- if (sim_fpu_is_snan (r))
- {
- *f = *r;
- f->class = sim_fpu_class_qnan;
- return sim_fpu_status_invalid_snan;
- }
- if (sim_fpu_is_qnan (l))
- {
- *f = *l;
- return 0;
- }
- if (sim_fpu_is_qnan (r))
- {
- *f = *r;
- return 0;
- }
+ if (sim_fpu_is_nan (l) || sim_fpu_is_nan (r))
+ return sim_fpu_op_nan (f, l, r);
if (sim_fpu_is_infinity (l))
{
if (sim_fpu_is_zero (r))
@@ -1423,30 +1380,8 @@ sim_fpu_div (sim_fpu *f,
const sim_fpu *l,
const sim_fpu *r)
{
- if (sim_fpu_is_snan (l))
- {
- *f = *l;
- f->class = sim_fpu_class_qnan;
- return sim_fpu_status_invalid_snan;
- }
- if (sim_fpu_is_snan (r))
- {
- *f = *r;
- f->class = sim_fpu_class_qnan;
- return sim_fpu_status_invalid_snan;
- }
- if (sim_fpu_is_qnan (l))
- {
- *f = *l;
- f->class = sim_fpu_class_qnan;
- return 0;
- }
- if (sim_fpu_is_qnan (r))
- {
- *f = *r;
- f->class = sim_fpu_class_qnan;
- return 0;
- }
+ if (sim_fpu_is_nan (l) || sim_fpu_is_nan (r))
+ return sim_fpu_op_nan (f, l, r);
if (sim_fpu_is_infinity (l))
{
if (sim_fpu_is_infinity (r))
@@ -1556,30 +1491,8 @@ sim_fpu_rem (sim_fpu *f,
const sim_fpu *l,
const sim_fpu *r)
{
- if (sim_fpu_is_snan (l))
- {
- *f = *l;
- f->class = sim_fpu_class_qnan;
- return sim_fpu_status_invalid_snan;
- }
- if (sim_fpu_is_snan (r))
- {
- *f = *r;
- f->class = sim_fpu_class_qnan;
- return sim_fpu_status_invalid_snan;
- }
- if (sim_fpu_is_qnan (l))
- {
- *f = *l;
- f->class = sim_fpu_class_qnan;
- return 0;
- }
- if (sim_fpu_is_qnan (r))
- {
- *f = *r;
- f->class = sim_fpu_class_qnan;
- return 0;
- }
+ if (sim_fpu_is_nan (l) || sim_fpu_is_nan (r))
+ return sim_fpu_op_nan (f, l, r);
if (sim_fpu_is_infinity (l))
{
*f = sim_fpu_qnan;
@@ -1639,28 +1552,8 @@ sim_fpu_max (sim_fpu *f,
const sim_fpu *l,
const sim_fpu *r)
{
- if (sim_fpu_is_snan (l))
- {
- *f = *l;
- f->class = sim_fpu_class_qnan;
- return sim_fpu_status_invalid_snan;
- }
- if (sim_fpu_is_snan (r))
- {
- *f = *r;
- f->class = sim_fpu_class_qnan;
- return sim_fpu_status_invalid_snan;
- }
- if (sim_fpu_is_qnan (l))
- {
- *f = *l;
- return 0;
- }
- if (sim_fpu_is_qnan (r))
- {
- *f = *r;
- return 0;
- }
+ if (sim_fpu_is_nan (l) || sim_fpu_is_nan (r))
+ return sim_fpu_op_nan (f, l, r);
if (sim_fpu_is_infinity (l))
{
if (sim_fpu_is_infinity (r)
@@ -1722,28 +1615,8 @@ sim_fpu_min (sim_fpu *f,
const sim_fpu *l,
const sim_fpu *r)
{
- if (sim_fpu_is_snan (l))
- {
- *f = *l;
- f->class = sim_fpu_class_qnan;
- return sim_fpu_status_invalid_snan;
- }
- if (sim_fpu_is_snan (r))
- {
- *f = *r;
- f->class = sim_fpu_class_qnan;
- return sim_fpu_status_invalid_snan;
- }
- if (sim_fpu_is_qnan (l))
- {
- *f = *l;
- return 0;
- }
- if (sim_fpu_is_qnan (r))
- {
- *f = *r;
- return 0;
- }
+ if (sim_fpu_is_nan (l) || sim_fpu_is_nan (r))
+ return sim_fpu_op_nan (f, l, r);
if (sim_fpu_is_infinity (l))
{
if (sim_fpu_is_infinity (r)
diff --git a/sim/common/sim-fpu.h b/sim/common/sim-fpu.h
index bcbe6ea16f2..34a56efae22 100644
--- a/sim/common/sim-fpu.h
+++ b/sim/common/sim-fpu.h
@@ -248,6 +248,13 @@ INLINE_SIM_FPU (int) sim_fpu_sqrt (sim_fpu *f,

+/* NaN handling. */
+
+INLINE_SIM_FPU (int) sim_fpu_op_nan (sim_fpu *f,
+ const sim_fpu *l, const sim_fpu *r);
+
+
+
/* Conversion of integer <-> floating point. */

INLINE_SIM_FPU (int) sim_fpu_i32to (sim_fpu *f, int32_t i,
--
2.17.1