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authorTom Musta <tommusta@gmail.com>2014-01-07 17:17:50 +0000
committerPeter Maydell <peter.maydell@linaro.org>2014-01-08 19:07:22 +0000
commit2f18bbf9844ad110e0e69ad22708f37cab1557f6 (patch)
treee0d83c4b329e6ed0f008ceae1de45537c22a3fc4 /fpu
parent3c85c37f254bdfaea4e105b5014a287b5cf9514b (diff)
downloadqemu-arm-2f18bbf9844ad110e0e69ad22708f37cab1557f6.tar.gz
softfloat: Add float32_to_uint64()
This patch adds the float32_to_uint64() routine, which converts a 32-bit floating point number to an unsigned 64 bit number. This contribution can be licensed under either the softfloat-2a or -2b license. Signed-off-by: Tom Musta <tommusta@gmail.com> Reviewed-by: Peter Maydell <peter.maydell@linaro.org> [PMM: removed harmless but silly int64_t casts] Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Richard Henderson <rth@twiddle.net>
Diffstat (limited to 'fpu')
-rw-r--r--fpu/softfloat.c46
1 files changed, 46 insertions, 0 deletions
diff --git a/fpu/softfloat.c b/fpu/softfloat.c
index d2e909593f..c2c1a5650b 100644
--- a/fpu/softfloat.c
+++ b/fpu/softfloat.c
@@ -1559,6 +1559,52 @@ int64 float32_to_int64( 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---which means in particular that the conversion is rounded
+| according to the current rounding mode. 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 exception flag.
+*----------------------------------------------------------------------------*/
+
+uint64 float32_to_uint64(float32 a STATUS_PARAM)
+{
+ flag aSign;
+ int_fast16_t aExp, shiftCount;
+ uint32_t aSig;
+ uint64_t aSig64, aSigExtra;
+ 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);
+ }
+
+ aSig64 = aSig;
+ aSig64 <<= 40;
+ shift64ExtraRightJamming(aSig64, 0, shiftCount, &aSig64, &aSigExtra);
+ return roundAndPackUint64(aSign, aSig64, aSigExtra STATUS_VAR);
+}
+
+/*----------------------------------------------------------------------------
+| 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