rsz: Add option for Steiner tree amending in net repair #5487
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Add an option `-amend_tree` to `repair_design` for requesting timing-aware amending of the Steiner trees used in the repair process. The buffers inserted by `repair_design` dictate much of the final buffer tree topology. The intent with `-amend_tree` is for `repair_design` to place its buffers in a way that has less of a chance of constraining us into a buffering topology which would be a timing bottleneck later on.
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| BufferedNetPtr pairing_candidate_; | ||
| std::vector<BufferedNetPtr> pending_candidates_; | ||
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| BufferedNet *place_ = NULL; |
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warning: use nullptr [modernize-use-nullptr]
| BufferedNet *place_ = NULL; | |
| BufferedNet *place_ = nullptr; |
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| BufferedNet *place_ = NULL; | ||
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| BufferedNet *upstream_ = NULL; |
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warning: use nullptr [modernize-use-nullptr]
| BufferedNet *upstream_ = NULL; | |
| BufferedNet *upstream_ = nullptr; |
| @@ -141,6 +141,87 @@ int RepairSetup::rebuffer(const Pin* drvr_pin) | |||
| return inserted_buffer_count; | |||
| } | |||
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| int RepairSetup::rebuffer(const Pin* drvr_pin, BufferedNetPtr bnet) | |||
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warning: the parameter 'bnet' is copied for each invocation but only used as a const reference; consider making it a const reference [performance-unnecessary-value-param]
| int RepairSetup::rebuffer(const Pin* drvr_pin, BufferedNetPtr bnet) | |
| int RepairSetup::rebuffer(const Pin* drvr_pin, const BufferedNetPtr& bnet) |
src/rsz/src/RepairSetup.hh:195:
- int rebuffer(const Pin* drvr_pin, BufferedNetPtr bnet);
+ int rebuffer(const Pin* drvr_pin, const BufferedNetPtr& bnet);| { | ||
| init(); | ||
| resizer_->incrementalParasiticsBegin(); | ||
| inserted_buffer_count_ = rebuffer(drvr_pin, bnet); |
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warning: parameter 'bnet' is passed by value and only copied once; consider moving it to avoid unnecessary copies [performance-unnecessary-value-param]
src/rsz/src/Rebuffer.cc:35:
- #include "BufferedNet.hh"
+ #include <utility>
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+ #include "BufferedNet.hh"| inserted_buffer_count_ = rebuffer(drvr_pin, bnet); | |
| inserted_buffer_count_ = rebuffer(drvr_pin, std::move(bnet)); |
| copyState(sta_); | ||
| } | ||
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| void dumpBranch(std::ostream &f, BufferedNetPtr net, float scale, int level=0) |
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warning: the parameter 'net' is copied for each invocation but only used as a const reference; consider making it a const reference [performance-unnecessary-value-param]
| void dumpBranch(std::ostream &f, BufferedNetPtr net, float scale, int level=0) | |
| void dumpBranch(std::ostream &f, const BufferedNetPtr& net, float scale, int level=0) |
| left = std::make_shared<BufferedNet>( | ||
| BufferedNetType::wire, loc, BufferedNet::null_layer, | ||
| left, corner_, resizer_); | ||
| if (loc != right->location()) |
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warning: statement should be inside braces [google-readability-braces-around-statements]
| if (loc != right->location()) | |
| if (loc != right->location()) { |
src/rsz/src/TreeAmending.cc:224:
- right, corner_, resizer_);
+ right, corner_, resizer_);
+ }| right, | ||
| resizer_); | ||
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| if (loc != net->location()) |
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warning: statement should be inside braces [google-readability-braces-around-statements]
| if (loc != net->location()) | |
| if (loc != net->location()) { |
src/rsz/src/TreeAmending.cc:237:
- else
+ } else| else | ||
| return junc; |
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warning: do not use 'else' after 'return' [readability-else-after-return]
| else | |
| return junc; | |
| return junc; |
| return std::make_shared<BufferedNet>( | ||
| BufferedNetType::wire, net->location(), BufferedNet::null_layer, | ||
| junc, corner_, resizer_); | ||
| else |
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warning: statement should be inside braces [google-readability-braces-around-statements]
else
^this fix will not be applied because it overlaps with another fix
| BufferedNetPtr seed = root->pairing_candidate_; | ||
| BufferedNet *place = seed->place_; | ||
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| place->pairing_candidate_ = NULL; |
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warning: use nullptr [modernize-use-nullptr]
| place->pairing_candidate_ = NULL; | |
| place->pairing_candidate_ = nullptr; |
Note: This is up so that it can be discussed. There are no plans to get it merged at the moment.
Add an option
-amend_treetorepair_designfor requestingtiming-aware amending of the Steiner trees used in the repair process.
The buffers inserted by
repair_designdictate much of the final buffertree topology. The intent with
-amend_treeis forrepair_designtoplace its buffers in a way that has less of a chance of constraining us
into a buffering topology which would be a timing bottleneck later on.