UCVTF (scalar, fixed-point)
Unsigned fixed-point convert to floating-point (scalar)
This instruction converts the unsigned value
in the 32-bit or 64-bit general-purpose source register to a
floating-point value using the rounding mode that is specified by the
FPCR, and
writes the result to the SIMD&FP destination register.
A floating-point exception can be generated by this instruction.
Depending on the settings in FPCR,
the exception results in either a flag being set in FPSR,
or a synchronous exception being generated.
For more information, see
Floating-point exception traps.
Depending on the settings in the CPACR_EL1,
CPTR_EL2, and CPTR_EL3 registers,
and the Security state and Exception level in which the instruction is executed,
an attempt to execute the instruction might be trapped.
0
0
1
1
1
1
0
0
0
0
0
1
1
0
1
1
UCVTF <Hd>, <Wn>, #<fbits>
1
1
1
UCVTF <Hd>, <Xn>, #<fbits>
0
0
0
UCVTF <Sd>, <Wn>, #<fbits>
1
0
0
UCVTF <Sd>, <Xn>, #<fbits>
0
0
1
UCVTF <Dd>, <Wn>, #<fbits>
1
0
1
UCVTF <Dd>, <Xn>, #<fbits>
if ftype == '10' || (ftype == '11' && !IsFeatureImplemented(FEAT_FP16)) then UNDEFINED;
if sf == '0' && scale<5> == '0' then UNDEFINED;
constant integer d = UInt(Rd);
constant integer n = UInt(Rn);
constant integer intsize = 32 << UInt(sf);
constant integer decode_fltsize = 8 << UInt(ftype EOR '10');
constant integer fracbits = 64 - UInt(scale);
constant boolean unsigned = TRUE;
<Hd>
Is the 16-bit name of the SIMD&FP destination register, encoded in the "Rd" field.
<Wn>
Is the 32-bit name of the general-purpose source register, encoded in the "Rn" field.
<fbits>
For the 32-bit to double-precision, 32-bit to half-precision and 32-bit to single-precision variant: is the number of bits after the binary point in the fixed-point source, in the range 1 to 32, encoded as 64 minus "scale".
<fbits>
For the 64-bit to double-precision, 64-bit to half-precision and 64-bit to single-precision variant: is the number of bits after the binary point in the fixed-point source, in the range 1 to 64, encoded as 64 minus "scale".
<Xn>
Is the 64-bit name of the general-purpose source register, encoded in the "Rn" field.
<Sd>
Is the 32-bit name of the SIMD&FP destination register, encoded in the "Rd" field.
<Dd>
Is the 64-bit name of the SIMD&FP destination register, encoded in the "Rd" field.
CheckFPEnabled64();
constant boolean merge = IsMerging(FPCR);
constant integer fltsize = if merge then 128 else decode_fltsize;
bits(fltsize) fltval = if merge then V[d, fltsize] else Zeros(fltsize);
constant bits(intsize) intval = X[n, intsize];
constant FPRounding rounding = FPRoundingMode(FPCR);
Elem[fltval, 0, decode_fltsize] = FixedToFP(intval, fracbits, unsigned,
FPCR, rounding, decode_fltsize);
V[d, fltsize] = fltval;