Conversion to unsigned fixed-point format (single precision) (Floating-point Convert Single to Unsigned-Word, round toward negative (Single))
This instruction arithmetically converts the single-precision floating-point format contents of general-purpose register reg1 to unsigned 32-bit fixed-point format, and stores the result in general-purpose register reg2.
The result is rounded in the -∞ direction, regardless of the current rounding mode.
When the source operand is infinite, not-a-number, or negative number, or when the rounded result is outside the range of 232 - 1 to 0, an IEEE754-defined invalid operation exception is detected.
If invalid operation exceptions are not enabled, the preservation bit (bit 4) of the FPSR register is set as an invalid operation and no exception occurs. The return value differs as follows, according to differences among sources.