This change adds the float32_to_uint64_round_to_zero function to the softfloat
library. This function fills out the complement of float32 to INT round-to-zero
conversion rountines, where INT is {int32_t, uint32_t, int64_t, uint64_t}.
This contribution can be licensed under either the softfloat-2a or -2b
license.
Signed-off-by: Tom Musta <tommu...@gmail.com>
Tested-by: Tom Musta <tommu...@gmail.com>
---
fpu/softfloat.c | 54 +++++++++++++++++++++++++++++++++++++++++++++++
include/fpu/softfloat.h | 1 +
2 files changed, 55 insertions(+), 0 deletions(-)
diff --git a/fpu/softfloat.c b/fpu/softfloat.c
index 5f02c16..d6df78a 100644
--- a/fpu/softfloat.c
+++ b/fpu/softfloat.c
@@ -1628,6 +1628,60 @@ uint64 float32_to_uint64(float32 a STATUS_PARAM)
/*----------------------------------------------------------------------------
| Returns the result of converting the single-precision floating-point value
+| `a' to the 64-bit unsigned integer format. The conversion is
+| performed according to the IEC/IEEE Standard for Binary Floating-Point
+| Arithmetic, except that the conversion is always rounded toward zero. If
+| `a' is a NaN, the largest unsigned integer is returned. Otherwise, if the
+| conversion overflows, the largest unsigned integer is returned. If the
+| 'a' is negative, the result is rounded and zero is returned; values that do
+| not round to zero will raise the inexact flag.
+*----------------------------------------------------------------------------*/
+
+uint64 float32_to_uint64_round_to_zero(float32 a STATUS_PARAM)
+{
+ flag aSign;
+ int_fast16_t aExp, shiftCount;
+ uint32_t aSig;
+ uint64_t aSig64;
+ uint64_t z;
+ a = float32_squash_input_denormal(a STATUS_VAR);
+
+ aSig = extractFloat32Frac(a);
+ aExp = extractFloat32Exp(a);
+ aSign = extractFloat32Sign(a);
+ if ((aSign) && (aExp > 126)) {
+ float_raise(float_flag_invalid STATUS_VAR);
+ if (float32_is_any_nan(a)) {
+ return LIT64(0xFFFFFFFFFFFFFFFF);
+ } else {
+ return 0;
+ }
+ }
+ shiftCount = 0xBE - aExp;
+ if (aExp) {
+ aSig |= 0x00800000;
+ }
+ if (shiftCount < 0) {
+ float_raise(float_flag_invalid STATUS_VAR);
+ return LIT64(0xFFFFFFFFFFFFFFFF);
+ } else if (aExp <= 0x7E) {
+ if (aExp | aSig) {
+ STATUS(float_exception_flags) |= float_flag_inexact;
+ }
+ return 0;
+ }
+
+ aSig64 = aSig;
+ aSig64 <<= 40;
+ z = aSig64 >> shiftCount;
+ if (shiftCount && ((uint64_t)(aSig64 << (-shiftCount & 63)))) {
+ STATUS(float_exception_flags) |= float_flag_inexact;
+ }
+ return z;
+}
+
+/*----------------------------------------------------------------------------
+| Returns the result of converting the single-precision floating-point value
| `a' to the 64-bit two's complement integer format. The conversion is
| performed according to the IEC/IEEE Standard for Binary Floating-Point
| Arithmetic, except that the conversion is always rounded toward zero. If
diff --git a/include/fpu/softfloat.h b/include/fpu/softfloat.h
index db878c1..4b3090c 100644
--- a/include/fpu/softfloat.h
+++ b/include/fpu/softfloat.h
@@ -342,6 +342,7 @@ uint32 float32_to_uint32( float32 STATUS_PARAM );
uint32 float32_to_uint32_round_to_zero( float32 STATUS_PARAM );
int64 float32_to_int64( float32 STATUS_PARAM );
uint64 float32_to_uint64(float32 STATUS_PARAM);
+uint64 float32_to_uint64_round_to_zero(float32 STATUS_PARAM);
int64 float32_to_int64_round_to_zero( float32 STATUS_PARAM );
float64 float32_to_float64( float32 STATUS_PARAM );
floatx80 float32_to_floatx80( float32 STATUS_PARAM );
--
1.7.1
