| Opcode/Instruction | Op/En | 64/32-bit Mode | CPUID Feature Flag | Description |
| F3 0F 2A /r CVTSI2SS xmm, r/m32 | RM | V/V | SSE | Convert one signed doubleword integer from r/m32 to one single-precision floating-point value in xmm. |
| F3 REX.W 0F 2A /r CVTSI2SS xmm, r/m64 | RM | V/N.E. | SSE | Convert one signed quadword integer from r/m64 to one single-precision floating-point value in xmm. |
| VEX.NDS.LIG.F3.0F.W0 2A /r VCVTSI2SS xmm1, xmm2, r/m32 | RVM | V/V | AVX | Convert one signed doubleword integer from r/m32 to one single-precision floating-point value in xmm1. |
| VEX.NDS.LIG.F3.0F.W1 2A /r VCVTSI2SS xmm1, xmm2, r/m64 | RVM | V/N.E.1 | AVX | Convert one signed quadword integer from r/m64 to one single-precision floating-point value in xmm1. |
Notes: 1. Encoding the VEX prefix with VEX.W=1 in non-64-bit mode is ignored.
| Op/En | Operand 1 | Operand 2 | Operand 3 | Operand 4 |
| RM | ModRM:reg (w) | ModRM:r/m (r) | NA | NA |
| RVM | ModRM:reg (w) | VEX.vvvv (r) | ModRM:r/m (r) | NA |
Converts a signed doubleword integer (or signed quadword integer if operand size is 64 bits) in the source operand (second operand) to a single-precision floating-point value in the destination operand (first operand). The source operand can be a general-purpose register or a memory location. The destination operand is an XMM register. The result is stored in the low doubleword of the destination operand, and the upper three doublewords are left unchanged. When a conversion is inexact, the value returned is rounded according to the rounding control bits in the MXCSR register.
Legacy SSE instructions: In 64-bit mode, the instruction can access additional registers (XMM8-XMM15, R8-R15) when used with a REX.R prefix. Use of the REX.W prefix promotes the instruction to 64-bit operands. See the summary chart at the beginning of this section for encoding data and limits.
128-bit Legacy SSE version: The destination and first source operand are the same. Bits (VLMAX-1:32) of the corresponding YMM destination register remain unchanged. VEX.128 encoded version: Bits (127:32) of the XMM register destination are copied from corresponding bits in the first source operand. Bits (VLMAX-1:128) of the destination YMM register are zeroed.
CVTSI2SS (128-bit Legacy SSE version) IF 64-Bit Mode And OperandSize = 64 THEN DEST[31:0] ← Convert_Integer_To_Single_Precision_Floating_Point(SRC[63:0]); ELSE DEST[31:0] ← Convert_Integer_To_Single_Precision_Floating_Point(SRC[31:0]); FI; DEST[VLMAX-1:32] (Unmodified) VCVTSI2SS (VEX.128 encoded version) IF 64-Bit Mode And OperandSize = 64 THEN DEST[31:0] ← Convert_Integer_To_Single_Precision_Floating_Point(SRC[63:0]); ELSE DEST[31:0] ← Convert_Integer_To_Single_Precision_Floating_Point(SRC[31:0]); FI; DEST[127:32] ← SRC1[127:32] DEST[VLMAX-1:128] ← 0
| CVTSI2SS: | __m128 | _mm_cvtsi32_ss(__m128 | a, int b) |
| CVTSI2SS: | __m128 | _mm_cvtsi64_ss(__m128 | a, __int64 b) |
Precision.
See Exceptions Type 3.