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| | {{DISPLAYTITLE:fmad}} | | {{DISPLAYTITLE:fmad}} |
| − | <div style="font-size:80%;line-height:90%;margin-bottom:2em">[[Speculation|realizing]] [[Encoding|exu stream]] [[Decode|exu block]] [[Phasing|compute phase]] operation [[Domains|in the decimal floating point value domain]] [[Rounding|and rounds use current dynamic rounding mode]]<br /> | + | <div style="font-size:80%;line-height:90%;margin-bottom:2em">[[Speculation|speculable]] [[Encoding|exu stream]] [[Decode|exu block]] [[Phasing|compute phase]] operation [[Domains|in the decimal floating point value domain]] [[Rounding|and rounds use current dynamic rounding mode]]<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 /> |
| − |
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| − | '''encoding:'''
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| − | <code style="font-size:100%"><b style="color:#050">fmad</b>(<span style="color:#009">[[Domains#d|d]]</span> <span title="belt operand from ops window">x</span>)</code>
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| − | ,
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| − | <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>
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| − | <br />
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| − |
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| − | {| class="mw-collapsible mw-collapsed wikitable" data-expandtext="▸" data-collapsetext="▾"
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| − | ! [[Cores|Core]] || [[Slot|In Slots]]|| [[Latency|Latencies]]
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| − | |-
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| − | | [[Cores/Decimal8/Encoding#fmad|Decimal8]] || E0 E1 || d,d:d=7 dv,dv:dv=7 q,q:q=8 qv,qv:qv=8
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| − | |-
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| − | | [[Cores/Decimal16/Encoding#fmad|Decimal16]] || E0 E1 || d,d:d=7 dv,dv:dv=7 q,q:q=8 qv,qv:qv=8
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| − | |}
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| − |
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| − | ----
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| − | <code style="font-size:130%"><b style="color:#050">fmad</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
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| − | window">z</span>, <span style="color:#009">[[Domains#d|d]]</span> <span title="belt operand from ops window">w</span>) → [[Domains#d|d]] r<sub>0</sub>, [[Domains#d|d]] r<sub>1</sub></code>
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| − | <div style="font-size:80%;line-height:90%;margin-bottom:2em">'''operands:''' [[Operands#likeFmasd|like Fmasd [dd:d]]]
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| − | </div>
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| − | 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 />
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| − | r<sub>0</sub> is x*y+z*w<br />
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| − | r<sub>1</sub> is x*y-z*w<br /><br />
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| − |
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| − | '''encoding:'''
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| − | <code style="font-size:100%"><b style="color:#050">fmad</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>
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| − | ,
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| − | <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>
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| − | <br />
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| − |
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| − | {| class="mw-collapsible mw-collapsed wikitable" data-expandtext="▸" data-collapsetext="▾"
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| − | ! [[Cores|Core]] || [[Slot|In Slots]]|| [[Latency|Latencies]]
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| − | |-
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| − | | [[Cores/Decimal8/Encoding#fmad|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
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| − | |-
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| − | | [[Cores/Decimal16/Encoding#fmad|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
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| − | |}
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| | [[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] |
Decimal floating point fused multiply-add.
As usual for those, it yields a higher precision than doing it separately, and is faster too.
Uses current rounding behaviour.
Returns x*y+z on the belt.
