Expansion of the TStreamerInfo actions. #16995
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This enables the StreamerInfoActions to enable the shortcuts that are possible in that case.
The version recorded 'here' is the version of the TStreamerInfo class not the user class
Even without schema evolution, the representation of a collection of enums on file is a `vector<int>` so `TStreamerElement::fType` and `TStreamerElement::fClassObject` should point to `vector<int>` while `TStreamerElement::fNewType` and `TStreamerElement::fNewClass` should point to the current in memory representaition `actualCollectionType< actualEnum >` that will know/remember what is the actual enum in memory representation.
Combine the code with the one use for the text actions
Combine the code with the one use for the text actions
To use be for case where the read and write implementation differs only slightly
To be used for function template that can be used for more than one actual looper (usually in conjunction with the LoopOverCollection template
Allow to share code with the collection loopers.
Test Results 18 files 18 suites 3d 21h 3m 41s ⏱️ For more details on these failures, see this check. Results for commit 17097bc. ♻️ This comment has been updated with latest results. |
We need to go with a specific action that hold the sub sequence (sequence for a base class) rather than insert of the action directly into the main sequence as (currently) the splicing of the action sequences needed to implemenent the split streaming in TTree relies on the order/index of the elements
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Thanks for this major improvement. I added some comments for the review. In general I believe it could be very useful to take this opportunity, perhaps to the documentation of TStreamerInfo, to add a 1 page explanation of what this major overhaul does, also explaining simply, without code and only in English, what the pre-existing code was doing.
| @@ -188,6 +194,59 @@ namespace TStreamerInfoActions | |||
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| struct TConfObject : public TConfiguration | |||
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Maybe could some comment here be useful to clarify why this new struct exists and how it will be used?
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Humm .. this is one of 'many' specialization of the action configuration object. However we might indeed be missing an overview document of the Sequence/Action/Configuration scaffolding.
| return 0; | ||
| } | ||
| class TConfNoFactor : public TConfiguration { | ||
| // Configuration object for the Float16/Double32 where a factor has been specified. |
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Could a more complete explanation help here, e.g. about what a factor is perhaps with an example?
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It is not quite the right place (and/or would lead to duplicate information). The full explanation is at
root/io/io/src/TBufferFile.cxx
Line 555 in 6735f22
As other place, maybe we should refer to TBufferFile::WriteFloat16
pcanal
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When executing the streaming on an object, the execution of the case covered by the case In its previous implementation (which is still used in a few rare cases involved backward compatibility), the case |
io/io/src/TStreamerInfoActions.cxx
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| @@ -1760,9 +1760,7 @@ namespace TStreamerInfoActions | |||
| // Read the class version and byte count from the buffer. | |||
| UInt_t start = 0; | |||
| UInt_t count = 0; | |||
| buf.ReadVersion(&start, &count, cl); | |||
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Could the commit message be extended explaining in which case the error is triggered?
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No error message was actually observed or is expected. The code is clearly asymmetrical between was is written and was is being read. The theorized error message is something like Can not find version 1 of class <wrong class name> and then moving along correctly (beside printing the error) when reading a file produced by the version with version 1 of TStreamerInfo, i.e. version v2.26 (Circa 2001)
This add TStreamerInfo actions for the case of base class, nested objects, externally assignment streamer and array thereof (
kBase,kAny,kStreamer,kStreamLoop) for both scalar and collection cases. It also expands the scope of the writing actions to cover the collections cases and the new cases (kBase,kAny,kStreamer,kStreamLoop)Companion PR of root-project/roottest#1224
When executing the streaming on an object, the execution of the case covered by the case
kBase,kAny,kStreamer,kStreamLoopwas migrated from using the legacy code within the source fileTStreamerInfoReadBuffer.cxxandTStreamerInfoWriteBuffer.cxxwhich is based on a pair of 'giant' switch statement to the newer framework based on the composition ofTStreamerInfoActions(and the corresponding collection:TActionSequence). The change fromswitchstatement to a set of function pointers allows to improve performance by executing for each data members only the code strictly necessary.In its previous implementation (which is still used in a few rare cases involved backward compatibility), the case
kBase(for both reading and writing) was forcing the use of theswitchstatement for all the data members of the base classes. This prevented the use of the new convert-on-write actions (with no existing corresponding implementation in the writeswitchstatement) that are necessary for supporting theEnumswith non default size.