Convert floating-point to integer converts a value in a register from floating-point to a 32-bit integer, using the rounding mode specified by the FPSCR 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 | 0 | 1 | M | 0 | Vm | ||||||||||
| cond | opc2 | op | |||||||||||||||||||||||||||||
if opc2 != '000' && opc2 != '10x' then SEE "Related encodings"; if size == '00' || (size == '01' && !HaveFP16Ext()) then UNDEFINED; if size == '01' && cond != '1110' then UNPREDICTABLE; to_integer = (opc2<2> == '1'); if to_integer then unsigned = (opc2<0> == '0'); rounding = if op == '1' then FPRounding_ZERO else FPRoundingMode(FPSCR); d = UInt(Vd:D); case size of when '01' esize = 16; m = UInt(Vm:M); when '10' esize = 32; m = UInt(Vm:M); when '11' esize = 64; m = UInt(M:Vm); else unsigned = (op == '0'); rounding = FPRoundingMode(FPSCR); m = UInt(Vm:M); case size of when '01' esize = 16; d = UInt(Vd:D); when '10' esize = 32; d = UInt(Vd:D); when '11' esize = 64; d = UInt(D:Vd);
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 | 0 | 1 | M | 0 | Vm | |||||||
| opc2 | op | ||||||||||||||||||||||||||||||
if opc2 != '000' && opc2 != '10x' then SEE "Related encodings"; if size == '00' || (size == '01' && !HaveFP16Ext()) then UNDEFINED; if size == '01' && InITBlock() then UNPREDICTABLE; to_integer = (opc2<2> == '1'); if to_integer then unsigned = (opc2<0> == '0'); rounding = if op == '1' then FPRounding_ZERO else FPRoundingMode(FPSCR); d = UInt(Vd:D); case size of when '01' esize = 16; m = UInt(Vm:M); when '10' esize = 32; m = UInt(Vm:M); when '11' esize = 64; m = UInt(M:Vm); else unsigned = (op == '0'); rounding = FPRoundingMode(FPSCR); m = UInt(Vm:M); case size of when '01' esize = 16; d = UInt(Vd:D); when '10' esize = 32; d = UInt(Vd:D); when '11' esize = 64; d = UInt(D:Vd);
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); if to_integer then case esize of when 16 S[d] = FPToFixed(S[m]<15:0>, 0, unsigned, FPSCR, rounding); when 32 S[d] = FPToFixed(S[m], 0, unsigned, FPSCR, rounding); when 64 S[d] = FPToFixed(D[m], 0, unsigned, FPSCR, rounding); else case esize of when 16 bits(16) fp16 = FixedToFP(S[m], 0, unsigned, FPSCR, rounding); S[d] = Zeros(16):fp16; when 32 S[d] = FixedToFP(S[m], 0, unsigned, FPSCR, rounding); when 64 D[d] = FixedToFP(S[m], 0, unsigned, FPSCR, rounding);
Internal version only: isa v00_96, pseudocode r8p5_00bet2_rc5 ; Build timestamp: 2019-03-28T07:59
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