x86doc › VCVTTPH2W - Convert Packed FP16 Values to Signed Word Integers

VCVTTPH2W—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 7C /r VCVTTPH2W xmm1{k1}{z}, xmm2/m128/m16bcst	A	V/V	AVX512-FP16 AVX512VL	Convert eight packed FP16 values in xmm2/m128/m16bcst to eight signed word integers, and store the result in xmm1 using truncation subject to writemask k1.
EVEX.256.66.MAP5.W0 7C /r VCVTTPH2W ymm1{k1}{z}, ymm2/m256/m16bcst	A	V/V	AVX512-FP16 AVX512VL	Convert sixteen packed FP16 values in ymm2/m256/m16bcst to sixteen signed word integers, and store the result in ymm1 using truncation subject to writemask k1.
EVEX.512.66.MAP5.W0 7C /r VCVTTPH2W zmm1{k1}{z}, zmm2/m512/m16bcst {sae}	A	V/V	AVX512-FP16	Convert thirty-two packed FP16 values in zmm2/m512/m16bcst to thirty-two signed word integers, and store the result in zmm1 using truncation subject to writemask k1.

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, a truncated (round toward zero) value is returned. 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 integer indefinite value is returned.

The destination elements are updated according to the writemask.

Operation

VCVTTPH2W dest, src

VL = 128, 256 or 512

KL := VL / 16

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_truncate(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

VCVTTPH2W __m512i _mm512_cvtt_roundph_epi16 (__m512h a, int sae);

VCVTTPH2W __m512i _mm512_mask_cvtt_roundph_epi16 (__m512i src, __mmask32 k, __m512h a, int sae);

VCVTTPH2W __m512i _mm512_maskz_cvtt_roundph_epi16 (__mmask32 k, __m512h a, int sae);

VCVTTPH2W __m128i _mm_cvttph_epi16 (__m128h a);

VCVTTPH2W __m128i _mm_mask_cvttph_epi16 (__m128i src, __mmask8 k, __m128h a);

VCVTTPH2W __m128i _mm_maskz_cvttph_epi16 (__mmask8 k, __m128h a);

VCVTTPH2W __m256i _mm256_cvttph_epi16 (__m256h a);

VCVTTPH2W __m256i _mm256_mask_cvttph_epi16 (__m256i src, __mmask16 k, __m256h a);

VCVTTPH2W __m256i _mm256_maskz_cvttph_epi16 (__mmask16 k, __m256h a);

VCVTTPH2W __m512i _mm512_cvttph_epi16 (__m512h a);

VCVTTPH2W __m512i _mm512_mask_cvttph_epi16 (__m512i src, __mmask32 k, __m512h a);

VCVTTPH2W __m512i _mm512_maskz_cvttph_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.”