FCVTNS (vector)

Floating-point Convert to Signed integer, rounding to nearest with ties to even (vector). This instruction converts a scalar or each element in a vector from a floating-point value to a signed integer value using the Round to Nearest rounding mode, 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.

It has encodings from 4 classes: Scalar half precision , Scalar single-precision and double-precision , Vector half precision and Vector single-precision and double-precision

Scalar half precision
(FEAT_FP16)

if !HaveFP16Ext() then UNDEFINED; integer d = UInt(Rd); integer n = UInt(Rn); integer esize = 16; integer datasize = esize; integer elements = 1; FPRounding rounding = FPDecodeRounding(o1:o2); boolean unsigned = (U == '1');

Scalar single-precision and double-precision

integer d = UInt(Rd); integer n = UInt(Rn); integer esize = 32 << UInt(sz); integer datasize = esize; integer elements = 1; FPRounding rounding = FPDecodeRounding(o1:o2); boolean unsigned = (U == '1');

Vector half precision
(FEAT_FP16)

if !HaveFP16Ext() then UNDEFINED; integer d = UInt(Rd); integer n = UInt(Rn); integer esize = 16; integer datasize = if Q == '1' then 128 else 64; integer elements = datasize DIV esize; FPRounding rounding = FPDecodeRounding(o1:o2); boolean unsigned = (U == '1');

Vector single-precision and double-precision

integer d = UInt(Rd); integer n = UInt(Rn); if sz:Q == '10' then UNDEFINED; integer esize = 32 << UInt(sz); integer datasize = if Q == '1' then 128 else 64; integer elements = datasize DIV esize; FPRounding rounding = FPDecodeRounding(o1:o2); boolean unsigned = (U == '1');