Floating-point Round to Integral, to nearest with ties to even (vector). This instruction rounds a vector of floating-point values in the SIMD&FP source register to integral floating-point values of the same size using the Round to Nearest rounding mode, and writes the result to the SIMD&FP destination register.
A zero input gives a zero result with the same sign, an infinite input gives an infinite result with the same sign, and a NaN is propagated as for normal arithmetic.
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 current Security state and Exception level, an attempt to execute the instruction might be trapped.
It has encodings from 2 classes: Half-precision and Single-precision and double-precision
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| 0 | Q | 0 | 0 | 1 | 1 | 1 | 0 | 0 | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 1 | 0 | 0 | 0 | 1 | 0 | Rn | Rd | ||||||||
| U | o2 | o1 | |||||||||||||||||||||||||||||
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; boolean exact = FALSE; FPRounding rounding; case U:o1:o2 of when '0xx' rounding = FPDecodeRounding(o1:o2); when '100' rounding = FPRounding_TIEAWAY; when '101' UNDEFINED; when '110' rounding = FPRoundingMode(FPCR); exact = TRUE; when '111' rounding = FPRoundingMode(FPCR);
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| 0 | Q | 0 | 0 | 1 | 1 | 1 | 0 | 0 | sz | 1 | 0 | 0 | 0 | 0 | 1 | 1 | 0 | 0 | 0 | 1 | 0 | Rn | Rd | ||||||||
| U | o2 | o1 | |||||||||||||||||||||||||||||
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; boolean exact = FALSE; FPRounding rounding; case U:o1:o2 of when '0xx' rounding = FPDecodeRounding(o1:o2); when '100' rounding = FPRounding_TIEAWAY; when '101' UNDEFINED; when '110' rounding = FPRoundingMode(FPCR); exact = TRUE; when '111' rounding = FPRoundingMode(FPCR);
| <Vd> |
Is the name of the SIMD&FP destination register, encoded in the "Rd" field. |
| <Vn> |
Is the name of the SIMD&FP source register, encoded in the "Rn" field. |
CheckFPAdvSIMDEnabled64(); bits(datasize) operand = V[n]; bits(datasize) result; bits(esize) element; for e = 0 to elements-1 element = Elem[operand, e, esize]; Elem[result, e, esize] = FPRoundInt(element, FPCR, rounding, exact); V[d] = result;
Internal version only: isa v32.13, AdvSIMD v29.04, pseudocode morello-2022-01_rc2, capabilities morello-2022-01_rc2 ; Build timestamp: 2022-01-11T11:23
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