You copied the Doc URL to your clipboard.

FCVTZS

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

Convert to the signed 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 sign-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
0110010101011010101PgZnZd

Half-precision to 16-bit

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

if !HaveSVE() 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 = FALSE;
FPRounding rounding = FPRounding_ZERO;

Half-precision to 32-bit

313029282726252423222120191817161514131211109876543210
0110010101011100101PgZnZd

Half-precision to 32-bit

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

if !HaveSVE() 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 = FALSE;
FPRounding rounding = FPRounding_ZERO;

Half-precision to 64-bit

313029282726252423222120191817161514131211109876543210
0110010101011110101PgZnZd

Half-precision to 64-bit

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

if !HaveSVE() 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 = FALSE;
FPRounding rounding = FPRounding_ZERO;

Single-precision to 32-bit

313029282726252423222120191817161514131211109876543210
0110010110011100101PgZnZd

Single-precision to 32-bit

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

if !HaveSVE() 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 = FALSE;
FPRounding rounding = FPRounding_ZERO;

Single-precision to 64-bit

313029282726252423222120191817161514131211109876543210
0110010111011100101PgZnZd

Single-precision to 64-bit

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

if !HaveSVE() 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 = FALSE;
FPRounding rounding = FPRounding_ZERO;

Double-precision to 32-bit

313029282726252423222120191817161514131211109876543210
0110010111011000101PgZnZd

Double-precision to 32-bit

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

if !HaveSVE() 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 = FALSE;
FPRounding rounding = FPRounding_ZERO;

Double-precision to 64-bit

313029282726252423222120191817161514131211109876543210
0110010111011110101PgZnZd

Double-precision to 64-bit

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

if !HaveSVE() 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 = FALSE;
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  = Z[n];
bits(VL) result = Z[d];

for e = 0 to elements-1
    bits(esize) element = Elem[operand, e, esize];
    if ElemP[mask, e, esize] == '1' then
        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 that conforms to all of the following requirements, otherwise the behavior of either or both instructions is unpredictable:

  • The MOVPRFX instruction must specify the same destination register as this instruction.
  • The destination register must not refer to architectural register state referenced by any other source operand register of this instruction.
The MOVPRFX instructions that can be used with this instruction are as follows:
  • An unpredicated MOVPRFX instruction.
  • A predicated MOVPRFX instruction using the same governing predicate register and source element size as this instruction.