VCVTT (BFloat16)

Converts the single-precision value in a single-precision register to BFloat16 format and writes the result in the top half of a single-precision register, preserving the bottom 16 bits of the register.

Unlike the BFloat16 multiplication instructions, this instruction honors all the control bits in the FPSCR that apply to single-precision arithmetic, including the rounding mode. This instruction can generate a floating-point exception which causes a cumulative exception bit in the FPSCR to be set, or a synchronous exception to be taken, depending on the enable bits in the FPSCR.

It has encodings from the following instruction sets: A32 ( A1 ) and T32 ( T1 ) .

A1
(FEAT_AA32BF16)

313029282726252423222120191817161514131211109876543210
!= 111111101D110011Vd100111M0Vm
cond

Encoding for the A1 variant

VCVTT{<c>}{<q>}.BF16.F32 <Sd>, <Sm>

Decode for this encoding

if !IsFeatureImplemented(FEAT_AA32BF16) then UNDEFINED; constant integer d = UInt(Vd:D); constant integer m = UInt(Vm:M);

T1
(FEAT_AA32BF16)

15141312111098765432101514131211109876543210
111011101D110011Vd100111M0Vm

Encoding for the T1 variant

VCVTT{<c>}{<q>}.BF16.F32 <Sd>, <Sm>

Decode for this encoding

if !IsFeatureImplemented(FEAT_AA32BF16) then UNDEFINED; constant integer d = UInt(Vd:D); constant integer m = UInt(Vm:M);

Assembler Symbols

<c>

See Standard assembler syntax fields.

<q>

See Standard assembler syntax fields.

<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.

Operation

if ConditionPassed() then EncodingSpecificOperations(); CheckVFPEnabled(TRUE); S[d]<31:16> = FPConvertBF(S[m], EffectiveFPCR());


Internal version only: isa v01_32, pseudocode v2024-12_rel ; Build timestamp: 2024-12-16T10:54

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