VCVTPH2W - Convert Packed FP16 Values to Signed Word Integers

Opcode/ Instruction

Op/ En

64/32 bit Mode Support

CPUID Feature Flag

Description

EVEX.128.66.MAP5.W0 7D /r VCVTPH2W xmm1{k1}{z}, xmm2/ m128/m16bcst

A

V/V

AVX512-FP16 AVX512VL

Convert packed FP16 values in xmm2/m128/ m16bcst to signed word integers, and store the result in xmm1.

EVEX.256.66.MAP5.W0 7D /r VCVTPH2W ymm1{k1}{z}, ymm2/ m256/m16bcst

A

V/V

AVX512-FP16 AVX512VL

Convert packed FP16 values in ymm2/m256/ m16bcst to signed word integers, and store the result in ymm1.

EVEX.512.66.MAP5.W0 7D /r VCVTPH2W zmm1{k1}{z}, zmm2/ m512/m16bcst {er}

A

V/V

AVX512-FP16

Convert packed FP16 values in zmm2/m512/ m16bcst to signed word integers, and store the result in zmm1.

Instruction Operand Encoding

Op/En

Tuple

Operand 1

Operand 2

Operand 3

Operand 4

A

Full

ModRM:reg (w)

ModRM:r/m (r)

N/A

N/A

Description

This instruction converts packed FP16 values in the source operand to signed word integers in the destination operand.

When a conversion is inexact, the value returned is rounded according to the rounding control bits in the MXCSR register or the embedded rounding control bits. If a converted result cannot be represented in the destination format, the floating-point invalid exception is raised, and if this exception is masked, the indefinite integer value is returned.

The destination elements are updated according to the writemask.

Operation

VCVTPH2W DEST, SRC 

VL = 128, 256 or 512
KL := VL / 16
IF *SRC is a register* and (VL = 512) and (EVEX.b = 1):
   SET_RM(EVEX.RC)
ELSE:
   SET_RM(MXCSR.RC)
FOR j := 0 TO KL-1:
   IF k1[j] OR *no writemask*:
       IF *SRC is memory* and EVEX.b = 1:
            tsrc := SRC.fp16[0]
       ELSE
            tsrc := SRC.fp16[j]
       DEST.word[j] := Convert_fp16_to_integer16(tsrc)
   ELSE IF *zeroing*:
       DEST.word[j] := 0
   // else dest.word[j] remains unchanged
DEST[MAXVL-1:VL] := 0

Intel C/C++ Compiler Intrinsic Equivalent 

VCVTPH2W __m512i _mm512_cvt_roundph_epi16 (__m512h a, int rounding);
VCVTPH2W __m512i _mm512_mask_cvt_roundph_epi16 (__m512i src, __mmask32 k, __m512h a, int rounding);
VCVTPH2W __m512i _mm512_maskz_cvt_roundph_epi16 (__mmask32 k, __m512h a, int rounding);
VCVTPH2W __m128i _mm_cvtph_epi16 (__m128h a);
VCVTPH2W __m128i _mm_mask_cvtph_epi16 (__m128i src, __mmask8 k, __m128h a);
VCVTPH2W __m128i _mm_maskz_cvtph_epi16 (__mmask8 k, __m128h a);
VCVTPH2W __m256i _mm256_cvtph_epi16 (__m256h a);
VCVTPH2W __m256i _mm256_mask_cvtph_epi16 (__m256i src, __mmask16 k, __m256h a);
VCVTPH2W __m256i _mm256_maskz_cvtph_epi16 (__mmask16 k, __m256h a);
VCVTPH2W __m512i _mm512_cvtph_epi16 (__m512h a);
VCVTPH2W __m512i _mm512_mask_cvtph_epi16 (__m512i src, __mmask32 k, __m512h a);
VCVTPH2W __m512i _mm512_maskz_cvtph_epi16 (__mmask32 k, __m512h a);

SIMD Floating-Point Exceptions

Invalid, Precision.

Other Exceptions

EVEX-encoded instructions, see Table 2-46, "Type E2 Class Exception Conditions."