image/svg+xml ADDSS—Add Scalar Single-Precision Floating-Point Values Instruction Operand Encoding Description Adds the low single-precision floating-point values from the second source operand and the first source operand, and stores the double-precision floating-point result in the destination operand. The second source operand can be an XMM register or a 64-bit memory location. The first source and destination operands are XMM registers. 128-bit Legacy SSE version: The first source and destination operands are the same. Bits (MAXVL-1:32) of the corresponding the destination register remain unchanged. EVEX and VEX.128 encoded version: The first source operand is encoded by EVEX.vvvv/VEX.vvvv. Bits (127:32) 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. EVEX version: The low doubleword element of the destination is updated according to the writemask. Software should ensure VADDSS is encoded with VEX.L=0. Encoding VADDSS with VEX.L=1 may encounter unpre- dictable behavior across different processor generations. Opcode/ Instruction Op / En 64/32 bit Mode Support CPUID Feature Flag Description F3 0F 58 /r ADDSS xmm1, xmm2/m32 AV/VSSEAdd the low single-precision floating-point value from xmm2/mem to xmm1 and store the result in xmm1. VEX.LIG.F3.0F.WIG 58 /r VADDSS xmm1,xmm2, xmm3/m32 BV/VAVXAdd the low single-precision floating-point value from xmm3/mem to xmm2 and store the result in xmm1. EVEX.LLIG.F3.0F.W0 58 /r VADDSS xmm1{k1}{z}, xmm2, xmm3/m32{er} CV/VAVX512FAdd the low single-precision floating-point value from xmm3/m32 to xmm2 and store the result in xmm1with writemask k1. Op/EnTuple TypeOperand 1Operand 2Operand 3Operand 4 ANAModRM:reg (r, w)ModRM:r/m (r)NANA BNAModRM:reg (w)VEX.vvvv (r)ModRM:r/m (r)NA CTuple1 ScalarModRM:reg (w)EVEX.vvvv (r)ModRM:r/m (r)NA image/svg+xml Operation VADDSS (EVEX encoded versions) IF (EVEX.b = 1) AND SRC2 *is a register* THEN SET_ROUNDING_MODE_FOR_THIS_INSTRUCTION(EVEX.RC); ELSE SET_ROUNDING_MODE_FOR_THIS_INSTRUCTION(MXCSR.RC); FI; IF k1[0] or *no writemask* THENDEST[31:0] := SRC1[31:0] + SRC2[31:0] ELSE IF *merging-masking*; merging-masking THEN *DEST[31:0] remains unchanged* ELSE ; zeroing-masking THEN DEST[31:0] := 0 FI; FI; DEST[127:32] := SRC1[127:32] DEST[MAXVL-1:128] := 0 VADDSS DEST, SRC1, SRC2 (VEX.128 encoded version) DEST[31:0] := SRC1[31:0] + SRC2[31:0] DEST[127:32] := SRC1[127:32] DEST[MAXVL-1:128] := 0 ADDSS DEST, SRC (128-bit Legacy SSE version) DEST[31:0] := DEST[31:0] + SRC[31:0] DEST[MAXVL-1:32] (Unmodified) Intel C/C++ Compiler Intrinsic Equivalent VADDSS __m128 _mm_mask_add_ss (__m128 s, __mmask8 k, __m128 a, __m128 b); VADDSS __m128 _mm_maskz_add_ss (__mmask8 k, __m128 a, __m128 b); VADDSS __m128 _mm_add_round_ss (__m128 a, __m128 b, int); VADDSS __m128 _mm_mask_add_round_ss (__m128 s, __mmask8 k, __m128 a, __m128 b, int); VADDSS __m128 _mm_maskz_add_round_ss (__mmask8 k, __m128 a, __m128 b, int); ADDSS __m128 _mm_add_ss (__m128 a, __m128 b); SIMD Floating-Point Exceptions Overflow, Underflow, Invalid, Precision, Denormal Other Exceptions VEX-encoded instruction, see Table2-20, “Type 3 Class Exception Conditions”. EVEX-encoded instruction, see Table2-47, “Type E3 Class Exception Conditions”. This UNOFFICIAL reference was generated from the official Intel® 64 and IA-32 Architectures Software Developer’s Manual by a dumb script. There is no guarantee that some parts aren't mangled or broken and is distributed WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE .