VCVTUSI2SH — Convert Unsigned Doubleword Integer to an FP16 Value

Instruction En Bit Mode Flag Support Instruction En Bit Mode Flag Support 64/32 CPUID Feature Instruction En Bit Mode Flag CPUID Feature Instruction En Bit Mode Flag Op/ 64/32 CPUID Feature Instruction En Bit Mode Flag 64/32 CPUID Feature Instruction En Bit Mode Flag CPUID Feature Instruction En Bit Mode Flag Op/ 64/32 CPUID Feature Support Description
EVEX.LLIG.F3.MAP5.W0 7B /r VCVTUSI2SH xmm1, xmm2, r32/m32 {er} A V/V1 AVX512-FP16 Convert an unsigned doubleword integer from r32/m32 to an FP16 value, and store the result in xmm1. Bits 127:16 from xmm2 are copied to xmm1[127:16].
EVEX.LLIG.F3.MAP5.W1 7B /r VCVTUSI2SH xmm1, xmm2, r64/m64 {er} A V/N.E. AVX512-FP16 Convert an unsigned quadword integer from r64/m64 to an FP16 value, and store the result in xmm1. Bits 127:16 from xmm2 are copied to xmm1[127:16].

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) VEX.vvvv (r) ModRM:r/m (r) N/A

Description

This instruction converts an unsigned doubleword integer (or unsigned quadword integer if operand size is 64 bits) in the second source operand to a FP16 value in the destination operand. The result is stored in the low word of the destination operand. When conversion is inexact, the value returned is rounded according to the rounding control bits in the MXCSR register or embedded rounding controls.

The second source operand can be a general-purpose register or a 32/64-bit memory location. The first source and destination operands are XMM registers. Bits 127:16 of the XMM register destination are copied from corresponding bits in the first source operand. Bits MAXVL-1:128 of the destination register are zeroed.

If the result of the convert operation is overflow and MXCSR.OM=0 then a SIMD exception will be raised with OE=1, PE=1.

Operation

VCVTUSI2SH dest, src1, src2

IF *SRC2 is a register* and (EVEX.b = 1):
    SET_RM(EVEX.RC)
ELSE:
    SET_RM(MXCSR.RC)
IF 64-mode and OperandSize == 64:
    DEST.fp16[0] := Convert_unsigned_integer64_to_fp16(SRC2.qword)
ELSE:
    DEST.fp16[0] := Convert_unsigned_integer32_to_fp16(SRC2.dword)
DEST[127:16] := SRC1[127:16]
DEST[MAXVL-1:128] := 0

Intel C/C++ Compiler Intrinsic Equivalent

VCVTUSI2SH __m128h _mm_cvt_roundu32_sh (__m128h a, unsigned int b, int rounding);
VCVTUSI2SH __m128h _mm_cvt_roundu64_sh (__m128h a, unsigned __int64 b, int rounding);
VCVTUSI2SH __m128h _mm_cvtu32_sh (__m128h a, unsigned int b);
VCVTUSI2SH __m128h _mm_cvtu64_sh (__m128h a, unsigned __int64 b);

SIMD Floating-Point Exceptions

Overflow, Precision.

Other Exceptions

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