VCVTSH2SI - Convert Low FP16 Value to Signed Integer

Opcode/

Instruction

Op/

En

64/32

bit Mode

Support

CPUID Feature

Flag

Description

EVEX.LLIG.F3.MAP5.W0 2D /r VCVTSH2SI r32, xmm1/m16 {er}

A

V/V1

AVX512-FP16

Convert the low FP16 element in xmm1/m16 to a signed integer and store the result in r32.

EVEX.LLIG.F3.MAP5.W1 2D /r VCVTSH2SI r64, xmm1/m16 {er}

A

V/N.E.

AVX512-FP16

Convert the low FP16 element in xmm1/m16 to a signed integer and store the result in r64.

1. Outside of 64b mode, the EVEX.W field is ignored. The instruction behaves as if W=0 was used.

Instruction Operand Encoding

Op/En

Tuple

Operand 1

Operand 2

Operand 3

Operand 4

A

Scalar

ModRM:reg (w)

ModRM:r/m (r)

N/A

N/A

Description

This instruction converts the low FP16 element in the source operand to a signed integer in the destination general purpose register.

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 integer indefinite value is returned.

Operation

VCVTSH2SI dest, src 

IF *SRC is a register* and (EVEX.b = 1):
   SET_RM(EVEX.RC)
ELSE:
   SET_RM(MXCSR.RC)
IF 64-mode and OperandSize == 64:
   DEST.qword := Convert_fp16_to_integer64(SRC.fp16[0])
ELSE:
   DEST.dword := Convert_fp16_to_integer32(SRC.fp16[0])

Intel C/C++ Compiler Intrinsic Equivalent 

VCVTSH2SI int _mm_cvt_roundsh_i32 (__m128h a, int rounding);
VCVTSH2SI __int64 _mm_cvt_roundsh_i64 (__m128h a, int rounding);
VCVTSH2SI int _mm_cvtsh_i32 (__m128h a);
VCVTSH2SI __int64 _mm_cvtsh_i64 (__m128h a);

SIMD Floating-Point Exceptions

Invalid, Precision.

Other Exceptions

EVEX-encoded instructions, see Table 2-48, "Type E3NF Class Exception Conditions."