softfloat: Use hard-float for {u}int64_to_float{32,64}

For the normal case of no additional scaling, this reduces the
profile contribution of int64_to_float64 to the testcase in the
linked issue from 0.81% to 0.04%.

Resolves: https://gitlab.com/qemu-project/qemu/-/issues/134
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This commit is contained in:
Richard Henderson 2021-05-16 09:52:52 -05:00
parent 90d004524e
commit 5d0204b82a

View File

@ -3559,6 +3559,13 @@ float32 int64_to_float32_scalbn(int64_t a, int scale, float_status *status)
{
FloatParts64 p;
/* Without scaling, there are no overflow concerns. */
if (likely(scale == 0) && can_use_fpu(status)) {
union_float32 ur;
ur.h = a;
return ur.s;
}
parts64_sint_to_float(&p, a, scale, status);
return float32_round_pack_canonical(&p, status);
}
@ -3592,6 +3599,13 @@ float64 int64_to_float64_scalbn(int64_t a, int scale, float_status *status)
{
FloatParts64 p;
/* Without scaling, there are no overflow concerns. */
if (likely(scale == 0) && can_use_fpu(status)) {
union_float64 ur;
ur.h = a;
return ur.s;
}
parts_sint_to_float(&p, a, scale, status);
return float64_round_pack_canonical(&p, status);
}
@ -3726,6 +3740,13 @@ float32 uint64_to_float32_scalbn(uint64_t a, int scale, float_status *status)
{
FloatParts64 p;
/* Without scaling, there are no overflow concerns. */
if (likely(scale == 0) && can_use_fpu(status)) {
union_float32 ur;
ur.h = a;
return ur.s;
}
parts_uint_to_float(&p, a, scale, status);
return float32_round_pack_canonical(&p, status);
}
@ -3759,6 +3780,13 @@ float64 uint64_to_float64_scalbn(uint64_t a, int scale, float_status *status)
{
FloatParts64 p;
/* Without scaling, there are no overflow concerns. */
if (likely(scale == 0) && can_use_fpu(status)) {
union_float64 ur;
ur.h = a;
return ur.s;
}
parts_uint_to_float(&p, a, scale, status);
return float64_round_pack_canonical(&p, status);
}