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author | Richard Henderson <richard.henderson@linaro.org> | 2021-05-16 09:52:52 -0500 |
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committer | Richard Henderson <richard.henderson@linaro.org> | 2021-06-03 14:09:03 -0700 |
commit | 5d0204b82ade0ea0630d6add894954135ee54ab1 (patch) | |
tree | 16fd0e145c30eda1500cb96918580d3d6fbb9b7b /fpu | |
parent | 90d004524e31a3efd3352bd1e6a3a312d266cfb0 (diff) | |
download | qemu-5d0204b82ade0ea0630d6add894954135ee54ab1.zip qemu-5d0204b82ade0ea0630d6add894954135ee54ab1.tar.gz qemu-5d0204b82ade0ea0630d6add894954135ee54ab1.tar.bz2 |
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>
Diffstat (limited to 'fpu')
-rw-r--r-- | fpu/softfloat.c | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/fpu/softfloat.c b/fpu/softfloat.c index 5026f51..1cb1628 100644 --- a/fpu/softfloat.c +++ b/fpu/softfloat.c @@ -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); } |