Difference between revisions of "Instruction Set/fmadp"

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{{DISPLAYTITLE:fmadp}}
 
{{DISPLAYTITLE:fmadp}}
 
<div style="font-size:80%;line-height:90%;margin-bottom:2em">[[Speculation|speculable]]&nbsp;&nbsp;[[Encoding|exu stream]]&nbsp;&nbsp;[[Decode|exu block]]&nbsp;&nbsp;[[Phasing|compute phase]]&nbsp;&nbsp; operation&nbsp;&nbsp; [[Domains|in the decimal floating point value domain]]&nbsp;&nbsp; [[Rounding|and rounds toward positive infinity]]<br />
 
<div style="font-size:80%;line-height:90%;margin-bottom:2em">[[Speculation|speculable]]&nbsp;&nbsp;[[Encoding|exu stream]]&nbsp;&nbsp;[[Decode|exu block]]&nbsp;&nbsp;[[Phasing|compute phase]]&nbsp;&nbsp; operation&nbsp;&nbsp; [[Domains|in the decimal floating point value domain]]&nbsp;&nbsp; [[Rounding|and rounds toward positive infinity]]<br />
'''native on:''' [[Cores/Decimal8|Decimal8]] [[Cores/Decimal16|Decimal16]] <br />
+
'''native on:''' [[Assembly|none]]<br />
 
</div>
 
</div>
  
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</div>
 
</div>
 
Returns x*y+z on the belt.<br />
 
Returns x*y+z on the belt.<br />
 
'''encoding:'''
 
<code style="font-size:100%"><b style="color:#050">fmadp</b>(<span style="color:#009">[[Domains#d|d]]</span> <span title="belt operand from ops window">x</span>)</code>
 
,
 
<code style="font-size:100%"><b style="color:#050">exuArgs</b>(<span style="color:#009">[[Domains#op|op]]</span> <span title="belt operand from ops window">arg0</span>, <span style="color:#009">[[Domains#op|op]]</span> <span title="belt operand from ops window">arg1</span>)</code>
 
<br />
 
 
{| class="mw-collapsible mw-collapsed wikitable" data-expandtext="&#9656;" data-collapsetext="&#9662;"
 
! [[Cores|Core]] || [[Slot|In Slots]]|| [[Latency|Latencies]]
 
|-
 
| [[Cores/Decimal8/Encoding#fmadp|Decimal8]] || E0 E1 || d,d:d=7 dv,dv:dv=7 q,q:q=8 qv,qv:qv=8
 
|-
 
| [[Cores/Decimal16/Encoding#fmadp|Decimal16]] || E0 E1 || d,d:d=7 dv,dv:dv=7 q,q:q=8 qv,qv:qv=8
 
|}
 
 
----
 
<code style="font-size:130%"><b style="color:#050">fmadp</b>(<span style="color:#009">[[Domains#d|d]]</span> <span title="belt operand from ops window">x</span>, <span style="color:#009">[[Domains#d|d]]</span> <span title="belt operand from ops window">y</span>, <span style="color:#009">[[Domains#d|d]]</span> <span title="belt operand from ops
 
            window">z</span>, <span style="color:#009">[[Domains#d|d]]</span> <span title="belt operand from ops window">w</span>) &#8594; [[Domains#d|d]] r<sub>0</sub>, [[Domains#d|d]] r<sub>1</sub></code>
 
<div style="font-size:80%;line-height:90%;margin-bottom:2em">'''operands:''' [[Operands#likeFmasd|like Fmasd [dd:d]]]
 
</div>
 
This is a fused multiply-add-subtract. An excellent way to make full use of all [[Functional Unit]]s in the 2 [[Slot]]s.<br />
 
r<sub>0</sub> is x*y+z*w<br />
 
r<sub>1</sub> is x*y-z*w<br /><br />
 
 
'''encoding:'''
 
<code style="font-size:100%"><b style="color:#050">fmadp</b>(<span style="color:#009">[[Domains#d|d]]</span> <span title="belt operand from ops window">x</span>, <span style="color:#009">[[Domains#d|d]]</span> <span title="belt operand from ops window">y</span>)</code>
 
,
 
<code style="font-size:100%"><b style="color:#050">exuArgs</b>(<span style="color:#009">[[Domains#op|op]]</span> <span title="belt operand from ops window">arg0</span>, <span style="color:#009">[[Domains#op|op]]</span> <span title="belt operand from ops window">arg1</span>)</code>
 
<br />
 
 
{| class="mw-collapsible mw-collapsed wikitable" data-expandtext="&#9656;" data-collapsetext="&#9662;"
 
! [[Cores|Core]] || [[Slot|In Slots]]|| [[Latency|Latencies]]
 
|-
 
| [[Cores/Decimal8/Encoding#fmadp|Decimal8]] || E0 || d,d:d,d=7,7 dv,dv:dv,dv=7,7 q,q:q,q=8,8 qv,qv:qv,qv=8,8
 
|-
 
| [[Cores/Decimal16/Encoding#fmadp|Decimal16]] || E0 || d,d:d,d=7,7 dv,dv:dv,dv=7,7 q,q:q,q=8,8 qv,qv:qv,qv=8,8
 
|}
 
  
  
 
[[Instruction_Set|Instruction Set, alphabetical]], [[Instruction Set by Category]], [http://millcomputing.com/instructions.html?collapse=7#ops Instruction Set, sortable, filterable]
 
[[Instruction_Set|Instruction Set, alphabetical]], [[Instruction Set by Category]], [http://millcomputing.com/instructions.html?collapse=7#ops Instruction Set, sortable, filterable]

Latest revision as of 14:10, 23 February 2021

speculable  exu stream  exu block  compute phase   operation   in the decimal floating point value domain   and rounds toward positive infinity

native on: none

Decimal floating point fused multiply-add. As usual for those, it yields a higher precision than doing it separately, and is faster too. Rounds towards positive infinity.


fmadp(d x, d y, d z) → d r0

operands: like Addd [dd:d]

Returns x*y+z on the belt.


Instruction Set, alphabetical, Instruction Set by Category, Instruction Set, sortable, filterable