Use move semantics to push objects on tapes #1249
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| assert(E && "must be provided"); | ||
| E = E->IgnoreImplicit(); | ||
| if (type.isNull()) | ||
| type = E->getType(); | ||
| QualType TapeType = |
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warning: misleading indentation: statement is indented too deeply [readability-misleading-indentation]
QualType TapeType =
^Additional context
lib/Differentiator/ReverseModeVisitor.cpp:97: did you mean this line to be inside this 'if'
if (type.isNull())
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@vgvassilev Is it broken or am I not seeing something?
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I think the problem is the indentation of the entire function.
This commit introduces move semantics to ``clad::pop`` and, where possible, ``clad::push``. The latter is done when local variables inside loops get promoted to the function scope, e.g.
```
while (cond) {
some_type x = init;
...
}
```
In the reverse mode, it becomes
```
some_type x;
while (cond) {
clad::push(_tape, x), x = init; // the value will be usefull in the reverse pass, we need to store it
...
}
```
In such cases, the commit introduces ``std::move``:
```
some_type x;
while (cond) {
clad::push(_tape, std::move(x)), x = init; // the value is stored right before it's overwritten so we can move it
...
}
```
This is useful for 2 reasons:
1) Moving objects is move efficient than copying.
2) This way, we can expect the underlying data (e.g. of stl containers) to stay at the same memory location in the reverse pass.
Codecov ReportAll modified and coverable lines are covered by tests ✅
Additional details and impacted files@@ Coverage Diff @@
## master #1249 +/- ##
=======================================
Coverage 94.66% 94.66%
=======================================
Files 51 51
Lines 8903 8910 +7
=======================================
+ Hits 8428 8435 +7
Misses 475 475
|
vgvassilev
approved these changes
Feb 25, 2025
| assert(E && "must be provided"); | ||
| E = E->IgnoreImplicit(); | ||
| if (type.isNull()) | ||
| type = E->getType(); | ||
| QualType TapeType = |
There was a problem hiding this comment.
I think the problem is the indentation of the entire function.
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This PR introduces move semantics to
clad::popand, where possible,clad::push. The latter is done when local variables inside loops get promoted to the function scope, e.g.In the reverse mode, it becomes
In such cases, the PR introduces
std::move:This is useful for 2 reasons:
This PR is opened to make #1247 smaller.