FCVTNS (scalar)

Floating-point Convert to Signed integer, rounding to nearest with ties to even (scalar). This instruction converts the floating-point value in the SIMD&FP source register to a 32-bit or 64-bit signed integer using the Round to Nearest rounding mode, and writes the result to the general-purpose 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 current Security state and Exception level, an attempt to execute the instruction might be trapped.

313029282726252423222120191817161514131211109876543210
sf0011110ftype100000000000RnRd
rmodeopcode

Half-precision to 32-bit (sf == 0 && ftype == 11)
(Armv8.2)

FCVTNS <Wd>, <Hn>

Half-precision to 64-bit (sf == 1 && ftype == 11)
(Armv8.2)

FCVTNS <Xd>, <Hn>

Single-precision to 32-bit (sf == 0 && ftype == 00)

FCVTNS <Wd>, <Sn>

Single-precision to 64-bit (sf == 1 && ftype == 00)

FCVTNS <Xd>, <Sn>

Double-precision to 32-bit (sf == 0 && ftype == 01)

FCVTNS <Wd>, <Dn>

Double-precision to 64-bit (sf == 1 && ftype == 01)

FCVTNS <Xd>, <Dn>

integer d = UInt(Rd); integer n = UInt(Rn); integer intsize = if sf == '1' then 64 else 32; integer fltsize; FPRounding rounding; case ftype of when '00' fltsize = 32; when '01' fltsize = 64; when '10' UNDEFINED; when '11' if HaveFP16Ext() then fltsize = 16; else UNDEFINED; rounding = FPDecodeRounding(rmode);

Assembler Symbols

<Wd>

Is the 32-bit name of the general-purpose destination register, encoded in the "Rd" field.

<Xd>

Is the 64-bit name of the general-purpose destination register, encoded in the "Rd" field.

<Sn>

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

<Hn>

Is the 16-bit name of the SIMD&FP source register, encoded in the "Rn" field.

<Dn>

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

Operation

CheckFPAdvSIMDEnabled64(); bits(fltsize) fltval; bits(intsize) intval; fltval = V[n]; intval = FPToFixed(fltval, 0, FALSE, FPCR, rounding); X[d] = intval;


Internal version only: isa v30.44, AdvSIMD v27.08, pseudocode v8.5-2019-06_rc2-5-g22901f2, sve v2019-06_rc4 ; Build timestamp: 2019-06-26T22:30

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