FJCVTZS

Floating-point Javascript Convert to Signed fixed-point, rounding toward Zero. This instruction converts the double-precision floating-point value in the SIMD&FP source register to a 32-bit signed integer using the Round towards Zero rounding mode, and writes the result to the general-purpose destination register. If the result is too large to be represented as a signed 32-bit integer, then the result is the integer modulo 232, as held in a 32-bit signed integer.

This instruction can generate a floating-point exception. 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.

Double-precision to 32-bit
(FEAT_JSCVT)

313029282726252423222120191817161514131211109876543210
0001111001111110000000RnRd
sfSftypermodeopcode

FJCVTZS <Wd>, <Dn>

if !IsFeatureImplemented(FEAT_JSCVT) then UNDEFINED; integer d = UInt(Rd); integer n = UInt(Rn); constant integer intsize = 32; constant integer fltsize = 64;

Assembler Symbols

<Wd>

Is the 32-bit name of the general-purpose 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

CheckFPAdvSIMDEnabled64(); bits(fltsize) fltval = V[n, fltsize]; bits(intsize) intval; bit z; (intval, z) = FPToFixedJS(fltval, FPCR, intsize); X[d, intsize] = intval; PSTATE.<N,Z,C,V> = '0':z:'00';


Internal version only: aarchmrs v2024-03_relA, pseudocode v2024-03_rel, sve v2024-03_rel ; Build timestamp: 2024-03-26T09:45

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