| Ticket UUID: | 931e4956b91b4545bb294a76faf82d13e11e74db | ||
| Title: | Interpreter command count not always incremented | ||
| Type: | Bug | Created on: | 2017-01-12 17:41:38 |
| Submitter: | apnadkarni | Assigned to: | nobody |
| Subsystem: | 47. Bytecode Compiler | Severity: | Minor |
| Priority: | 5 Medium | Last modified: | 2017-01-12 17:43:00 |
| Status: | Open | Closed by: | nobody |
| Resolution: | None | Closed on: | |
| Version: | 8.6.6 | ||
| Description: | ||||
What exactly does [info cmdcount] count? Based on below, it does not seem to count either [incr] or [set] though it does count itself. (ip is a slave interp)
% ip eval {info cmdcount}
377
% ip eval {incr i}
1
% ip eval {incr i}
2
% ip eval {incr i}
3
% ip eval {incr i}
4
% ip eval {incr i}
5
% ip eval {info cmdcount}
378
% ip eval {set x 1}
1
% ip eval {set x 1}
1
% ip eval {set x 1}
1
% ip eval {set x 1}
1
% ip eval {info cmdcount}
379
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| User Comments: | ||||
apnadkarni added on 2017-01-12 17:43:00:
Speculation by dgp on the chat:
[23:59] apn the [incr i] within the slave interpreter should increment cmdCount for that slave, no?
[23:59] dgp One increment happens in the "Dispatch" of any objCmdProc.
[23:59] dgp That captures all the "direct eval" of any command.
[00:00] apn That's in tclBasic.c
[00:00] dgp The other increment is in bytecode execution.
[00:00] dgp and has been #ifdef'ed to within an inch of its life.
[00:01] dgp and peepholed etc etc.
[00:01] dgp Quick, likely faulty analysis.....
[00:01] dgp Bytecode execution has given command counting task to INST_START_CMD
[00:02] dgp Over time INST_START_CMD was perceived as too much performance drag for too little value, so it's been suppressed in many situations.
[00:03] dgp So don't expect bytecode to get correct answers.
[00:03] dgp If not for the [interp limit], I'd say just ignore it.
[00:04] dgp take a look at the bytecode disassembly for more explorations.
[00:04] apn hmm, also turns out that [ip eval {set x 1; set x 1; info cmdcount}] does increment cmdCount correctly
[00:05] apn So it's almost like for a single command, INST_START_CMD gets skipped. Or something like that
[00:05] dgp "optimized"
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