Convert floating-point to integer with Round towards Zero converts a value in a register from floating-point to a 32-bit integer, using the Round towards Zero rounding mode, and places the result in a second register.
VCVT (between floating-point and fixed-point, floating-point) describes conversions between floating-point and 16-bit integers.
Depending on settings in the CPACR, NSACR, HCPTR, and FPEXC registers, and the Security state and PE mode in which the instruction is executed, an attempt to execute the instruction might be undefined, or trapped to Hyp mode. For more information see Enabling Advanced SIMD and floating-point support.
It has encodings from the following instruction sets: A32 ( A1 ) and T32 ( T1 ) .
| 31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
| != 1111 | 1 | 1 | 1 | 0 | 1 | D | 1 | 1 | 1 | 1 | 0 | x | Vd | 1 | 0 | size | 1 | 1 | M | 0 | Vm | ||||||||||
| cond | opc2 | op | |||||||||||||||||||||||||||||
if opc2 != '000' && opc2 != '10x' then SEE "Related encodings"; if size == '00' || (size == '01' && !IsFeatureImplemented(FEAT_FP16)) then UNDEFINED; if size == '01' && cond != '1110' then UNPREDICTABLE; constant integer esize = 8 << UInt(size); constant to_integer = (opc2<2> == '1'); constant integer d = if !to_integer && size == '11' then UInt(D:Vd) else UInt(Vd:D); constant integer m = if to_integer && size == '11' then UInt(M:Vm) else UInt(Vm:M); constant boolean unsigned = (if to_integer then opc2<0> else op) == '0'; constant boolean zero_rounding = to_integer && (op == '1');
If size == '01' && cond != '1110', then one of the following behaviors must occur:
| 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
| 1 | 1 | 1 | 0 | 1 | 1 | 1 | 0 | 1 | D | 1 | 1 | 1 | 1 | 0 | x | Vd | 1 | 0 | size | 1 | 1 | M | 0 | Vm | |||||||
| opc2 | op | ||||||||||||||||||||||||||||||
if opc2 != '000' && opc2 != '10x' then SEE "Related encodings"; if size == '00' || (size == '01' && !IsFeatureImplemented(FEAT_FP16)) then UNDEFINED; if size == '01' && InITBlock() then UNPREDICTABLE; constant integer esize = 8 << UInt(size); constant to_integer = (opc2<2> == '1'); constant integer m = if to_integer && size == '11' then UInt(M:Vm) else UInt(Vm:M); constant integer d = if !to_integer && size == '11' then UInt(D:Vd) else UInt(Vd:D); constant boolean unsigned = (if to_integer then opc2<0> else op) == '0'; constant boolean zero_rounding = to_integer && op == '1';
If size == '01' && InITBlock(), then one of the following behaviors must occur:
Related encodings: See Floating-point data-processing for the T32 instruction set, or Floating-point data-processing for the A32 instruction set.
| <c> |
| <q> |
| <Sd> |
Is the 32-bit name of the SIMD&FP destination register, encoded in the "Vd:D" field. |
| <Sm> |
Is the 32-bit name of the SIMD&FP source register, encoded in the "Vm:M" field. |
| <Dm> |
Is the 64-bit name of the SIMD&FP source register, encoded in the "M:Vm" field. |
if ConditionPassed() then EncodingSpecificOperations(); CheckVFPEnabled(TRUE); constant FPCR_Type fpcr = EffectiveFPCR(); constant FPRounding rounding = if zero_rounding then FPRounding_ZERO else FPRoundingMode(fpcr); if to_integer then case esize of when 16 S[d] = FPToFixed(H[m], 0, unsigned, fpcr, rounding, 32); when 32 S[d] = FPToFixed(S[m], 0, unsigned, fpcr, rounding, 32); when 64 S[d] = FPToFixed(D[m], 0, unsigned, fpcr, rounding, 32); else case esize of when 16 H[d] = FixedToFP(S[m], 0, unsigned, fpcr, rounding, 16); when 32 S[d] = FixedToFP(S[m], 0, unsigned, fpcr, rounding, 32); when 64 D[d] = FixedToFP(S[m], 0, unsigned, fpcr, rounding, 64);
Internal version only: isa v01_32, pseudocode v2024-12_rel ; Build timestamp: 2024-12-16T10:54
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