FCVTZU

Floating-point convert to unsigned integer, rounding toward zero (predicated)

Convert to the unsigned integer nearer to zero from each active floating-point element of the source vector, and place the results in the corresponding elements of the destination vector. Inactive elements in the destination vector register remain unmodified.

If the input and result types have a different size the smaller type is held unpacked in the least significant bits of elements of the larger size. When the input is the smaller type the upper bits of each source element are ignored. When the result is the smaller type the results are zero-extended to fill each destination element.

It has encodings from 7 classes: Half-precision to 16-bit , Half-precision to 32-bit , Half-precision to 64-bit , Single-precision to 32-bit , Single-precision to 64-bit , Double-precision to 32-bit and Double-precision to 64-bit

Half-precision to 16-bit

313029282726252423222120191817161514131211109876543210
0110010101011011101PgZnZd
int_U

FCVTZU <Zd>.H, <Pg>/M, <Zn>.H

if !HaveSVE() && !HaveSME() then UNDEFINED; integer esize = 16; integer g = UInt(Pg); integer n = UInt(Zn); integer d = UInt(Zd); integer s_esize = 16; integer d_esize = 16; boolean unsigned = TRUE; FPRounding rounding = FPRounding_ZERO;

Half-precision to 32-bit

313029282726252423222120191817161514131211109876543210
0110010101011101101PgZnZd
int_U

FCVTZU <Zd>.S, <Pg>/M, <Zn>.H

if !HaveSVE() && !HaveSME() then UNDEFINED; integer esize = 32; integer g = UInt(Pg); integer n = UInt(Zn); integer d = UInt(Zd); integer s_esize = 16; integer d_esize = 32; boolean unsigned = TRUE; FPRounding rounding = FPRounding_ZERO;

Half-precision to 64-bit

313029282726252423222120191817161514131211109876543210
0110010101011111101PgZnZd
int_U

FCVTZU <Zd>.D, <Pg>/M, <Zn>.H

if !HaveSVE() && !HaveSME() then UNDEFINED; integer esize = 64; integer g = UInt(Pg); integer n = UInt(Zn); integer d = UInt(Zd); integer s_esize = 16; integer d_esize = 64; boolean unsigned = TRUE; FPRounding rounding = FPRounding_ZERO;

Single-precision to 32-bit

313029282726252423222120191817161514131211109876543210
0110010110011101101PgZnZd
int_U

FCVTZU <Zd>.S, <Pg>/M, <Zn>.S

if !HaveSVE() && !HaveSME() then UNDEFINED; integer esize = 32; integer g = UInt(Pg); integer n = UInt(Zn); integer d = UInt(Zd); integer s_esize = 32; integer d_esize = 32; boolean unsigned = TRUE; FPRounding rounding = FPRounding_ZERO;

Single-precision to 64-bit

313029282726252423222120191817161514131211109876543210
0110010111011101101PgZnZd
int_U

FCVTZU <Zd>.D, <Pg>/M, <Zn>.S

if !HaveSVE() && !HaveSME() then UNDEFINED; integer esize = 64; integer g = UInt(Pg); integer n = UInt(Zn); integer d = UInt(Zd); integer s_esize = 32; integer d_esize = 64; boolean unsigned = TRUE; FPRounding rounding = FPRounding_ZERO;

Double-precision to 32-bit

313029282726252423222120191817161514131211109876543210
0110010111011001101PgZnZd
int_U

FCVTZU <Zd>.S, <Pg>/M, <Zn>.D

if !HaveSVE() && !HaveSME() then UNDEFINED; integer esize = 64; integer g = UInt(Pg); integer n = UInt(Zn); integer d = UInt(Zd); integer s_esize = 64; integer d_esize = 32; boolean unsigned = TRUE; FPRounding rounding = FPRounding_ZERO;

Double-precision to 64-bit

313029282726252423222120191817161514131211109876543210
0110010111011111101PgZnZd
int_U

FCVTZU <Zd>.D, <Pg>/M, <Zn>.D

if !HaveSVE() && !HaveSME() then UNDEFINED; integer esize = 64; integer g = UInt(Pg); integer n = UInt(Zn); integer d = UInt(Zd); integer s_esize = 64; integer d_esize = 64; boolean unsigned = TRUE; FPRounding rounding = FPRounding_ZERO;

Assembler Symbols

<Zd>

Is the name of the destination scalable vector register, encoded in the "Zd" field.

<Pg>

Is the name of the governing scalable predicate register P0-P7, encoded in the "Pg" field.

<Zn>

Is the name of the source scalable vector register, encoded in the "Zn" field.

Operation

CheckSVEEnabled(); integer elements = VL DIV esize; bits(PL) mask = P[g]; bits(VL) operand = if AnyActiveElement(mask, esize) then Z[n] else Zeros(); bits(VL) result = Z[d]; for e = 0 to elements-1 if ElemP[mask, e, esize] == '1' then bits(esize) element = Elem[operand, e, esize]; bits(d_esize) res = FPToFixed(element<s_esize-1:0>, 0, unsigned, FPCR[], rounding); Elem[result, e, esize] = Extend(res, unsigned); Z[d] = result;

Operational information

This instruction might be immediately preceded in program order by a MOVPRFX instruction. The MOVPRFX instruction must conform to all of the following requirements, otherwise the behavior of the MOVPRFX and this instruction is unpredictable:


Internal version only: isa v33.11seprel, AdvSIMD v29.05, pseudocode v2021-09_rel, sve v2021-09_rc3d ; Build timestamp: 2021-10-06T11:41

Copyright © 2010-2021 Arm Limited or its affiliates. All rights reserved. This document is Non-Confidential.