ia32-64/x86/divsd.html
2025-07-08 02:23:29 -03:00

136 lines
6.4 KiB
HTML
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml" xmlns:svg="http://www.w3.org/2000/svg" xmlns:x86="http://www.felixcloutier.com/x86"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"><link rel="stylesheet" type="text/css" href="style.css"></link><title>DIVSD
— Divide Scalar Double Precision Floating-Point Value</title></head><body><header><nav><ul><li><a href='index.html'>Index</a></li><li>December 2023</li></ul></nav></header><h1>DIVSD
— Divide Scalar Double Precision Floating-Point Value</h1>
<table>
<tr>
<th>Opcode/Instruction</th>
<th>Op / En</th>
<th>64/32 bit Mode Support</th>
<th>CPUID Feature Flag</th>
<th>Description</th></tr>
<tr>
<td>F2 0F 5E /r DIVSD xmm1, xmm2/m64</td>
<td>A</td>
<td>V/V</td>
<td>SSE2</td>
<td>Divide low double precision floating-point value in xmm1 by low double precision floating-point value in xmm2/m64.</td></tr>
<tr>
<td>VEX.LIG.F2.0F.WIG 5E /r VDIVSD xmm1, xmm2, xmm3/m64</td>
<td>B</td>
<td>V/V</td>
<td>AVX</td>
<td>Divide low double precision floating-point value in xmm2 by low double precision floating-point value in xmm3/m64.</td></tr>
<tr>
<td>EVEX.LLIG.F2.0F.W1 5E /r VDIVSD xmm1 {k1}{z}, xmm2, xmm3/m64{er}</td>
<td>C</td>
<td>V/V</td>
<td>AVX512F</td>
<td>Divide low double precision floating-point value in xmm2 by low double precision floating-point value in xmm3/m64.</td></tr></table>
<h2 id="instruction-operand-encoding">Instruction Operand Encoding<a class="anchor" href="#instruction-operand-encoding">
</a></h2>
<table>
<tr>
<th>Op/En</th>
<th>Tuple Type</th>
<th>Operand 1</th>
<th>Operand 2</th>
<th>Operand 3</th>
<th>Operand 4</th></tr>
<tr>
<td>A</td>
<td>N/A</td>
<td>ModRM:reg (r, w)</td>
<td>ModRM:r/m (r)</td>
<td>N/A</td>
<td>N/A</td></tr>
<tr>
<td>B</td>
<td>N/A</td>
<td>ModRM:reg (w)</td>
<td>VEX.vvvv (r)</td>
<td>ModRM:r/m (r)</td>
<td>N/A</td></tr>
<tr>
<td>C</td>
<td>Tuple1 Scalar</td>
<td>ModRM:reg (w)</td>
<td>EVEX.vvvv (r)</td>
<td>ModRM:r/m (r)</td>
<td>N/A</td></tr></table>
<h2 id="description">Description<a class="anchor" href="#description">
</a></h2>
<p>Divides the low double precision floating-point value in the first source operand by the low double precision floating-point value in the second 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 are XMM registers.</p>
<p>128-bit Legacy SSE version: The first source operand and the destination operand are the same. Bits (MAXVL-1:64) of the corresponding ZMM destination register remain unchanged.</p>
<p>VEX.128 encoded version: The first source operand is an xmm register encoded by VEX.vvvv. The quadword at bits 127:64 of the destination operand is copied from the corresponding quadword of the first source operand. Bits (MAXVL-1:128) of the destination register are zeroed.</p>
<p>EVEX.128 encoded version: The first source operand is an xmm register encoded by EVEX.vvvv. The quadword element of the destination operand at bits 127:64 are copied from the first source operand. Bits (MAXVL-1:128) of the destination register are zeroed.</p>
<p>EVEX version: The low quadword element of the destination is updated according to the writemask.</p>
<p>Software should ensure VDIVSD is encoded with VEX.L=0. Encoding VDIVSD with VEX.L=1 may encounter unpredictable behavior across different processor generations.</p>
<h2 id="operation">Operation<a class="anchor" href="#operation">
</a></h2>
<h3 id="vdivsd--evex-encoded-version-">VDIVSD (EVEX Encoded Version)<a class="anchor" href="#vdivsd--evex-encoded-version-">
</a></h3>
<pre>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*
THEN DEST[63:0] := SRC1[63:0] / SRC2[63:0]
ELSE
IF *merging-masking* ; merging-masking
THEN *DEST[63:0] remains unchanged*
ELSE ; zeroing-masking
THEN DEST[63:0] := 0
FI;
FI;
DEST[127:64] := SRC1[127:64]
DEST[MAXVL-1:128] := 0
</pre>
<h3 id="vdivsd--vex-128-encoded-version-">VDIVSD (VEX.128 Encoded Version)<a class="anchor" href="#vdivsd--vex-128-encoded-version-">
</a></h3>
<pre>DEST[63:0] := SRC1[63:0] / SRC2[63:0]
DEST[127:64] := SRC1[127:64]
DEST[MAXVL-1:128] := 0
</pre>
<h3 id="divsd--128-bit-legacy-sse-version-">DIVSD (128-bit Legacy SSE Version)<a class="anchor" href="#divsd--128-bit-legacy-sse-version-">
</a></h3>
<pre>DEST[63:0] := DEST[63:0] / SRC[63:0]
DEST[MAXVL-1:64] (Unmodified)
</pre>
<h2 id="intel-c-c++-compiler-intrinsic-equivalent">Intel C/C++ Compiler Intrinsic Equivalent<a class="anchor" href="#intel-c-c++-compiler-intrinsic-equivalent">
</a></h2>
<pre>VDIVSD __m128d _mm_mask_div_sd(__m128d s, __mmask8 k, __m128d a, __m128d b);
</pre>
<pre>VDIVSD __m128d _mm_maskz_div_sd( __mmask8 k, __m128d a, __m128d b);
</pre>
<pre>VDIVSD __m128d _mm_div_round_sd( __m128d a, __m128d b, int);
</pre>
<pre>VDIVSD __m128d _mm_mask_div_round_sd(__m128d s, __mmask8 k, __m128d a, __m128d b, int);
</pre>
<pre>VDIVSD __m128d _mm_maskz_div_round_sd( __mmask8 k, __m128d a, __m128d b, int);
</pre>
<pre>DIVSD __m128d _mm_div_sd (__m128d a, __m128d b);
</pre>
<h2 class="exceptions" id="simd-floating-point-exceptions">SIMD Floating-Point Exceptions<a class="anchor" href="#simd-floating-point-exceptions">
</a></h2>
<p>Overflow, Underflow, Invalid, Divide-by-Zero, Precision, Denormal.</p>
<h2 class="exceptions" id="other-exceptions">Other Exceptions<a class="anchor" href="#other-exceptions">
</a></h2>
<p>VEX-encoded instructions, see <span class="not-imported">Table 2-20</span>, “Type 3 Class Exception Conditions.”</p>
<p>EVEX-encoded instructions, see <span class="not-imported">Table 2-47</span>, “Type E3 Class Exception Conditions.”</p><footer><p>
This UNOFFICIAL, mechanically-separated, non-verified reference is provided for convenience, but it may be
inc<span style="opacity: 0.2">omp</span>lete or b<sub>r</sub>oke<sub>n</sub> in various obvious or non-obvious
ways. Refer to <a href="https://software.intel.com/en-us/download/intel-64-and-ia-32-architectures-sdm-combined-volumes-1-2a-2b-2c-2d-3a-3b-3c-3d-and-4">Intel® 64 and IA-32 Architectures Software Developers Manual</a> for anything serious.
</p></footer></body></html>