FRINT64Z (scalar)

Floating-point Round to 64-bit Integer toward Zero (scalar). This instruction rounds a floating-point value in the SIMD&FP source register to an integral floating-point value that fits into a 64-bit integer size using the Round towards Zero rounding mode, and writes the result to the SIMD&FP destination register.

A zero input returns a zero result with the same sign. When the result value is not numerically equal to the {corresponding} input value, an Inexact exception is raised. When the input is infinite, NaN or out-of-range, the instruction returns {for the corresponding result value} the most negative integer representable in the destination size, and an Invalid Operation floating-point exception is raised.

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.

Floating-point
(FEAT_FRINTTS)

313029282726252423222120191817161514131211109876543210
000111100x101001010000RnRd
MSftypeop

Single-precision (ftype == 00)

FRINT64Z <Sd>, <Sn>

Double-precision (ftype == 01)

FRINT64Z <Dd>, <Dn>

if !IsFeatureImplemented(FEAT_FRINTTS) then UNDEFINED; if ftype IN {'1x'} then UNDEFINED; integer d = UInt(Rd); integer n = UInt(Rn); constant integer esize = 32 << UInt(ftype); constant integer intsize = 32 << 1;

Assembler Symbols

<Sd>

Is the 32-bit name of the SIMD&FP destination register, encoded in the "Rd" field.

<Sn>

Is the 32-bit name of the SIMD&FP source register, encoded in the "Rn" field.

<Dd>

Is the 64-bit name of the SIMD&FP destination register, encoded in the "Rd" field.

<Dn>

Is the 64-bit name of the SIMD&FP source register, encoded in the "Rn" field.

Operation

CheckFPEnabled64(); boolean merge = IsMerging(FPCR); bits(128) result = if merge then V[d, 128] else Zeros(128); bits(esize) operand = V[n, esize]; Elem[result, 0, esize] = FPRoundIntN(operand, FPCR, FPRounding_ZERO, intsize); V[d, 128] = result;


Internal version only: aarchmrs v2023-12_rel, pseudocode v2023-12_rel, sve v2023-12_rel ; Build timestamp: 2023-12-15T16:46

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