What does deoptimize mean in Rollup source code - rollup

There are lots of deoptimizeXXX methods in the rollup source code.
deoptimizePath, deoptimizeThisOnEventAtPath, etc. Every time I meet some calls to these methods, I do not understand.
I really want to know some low level tech in rollup's tree-shaking algorithm.
btw rollup's discord link which is (is.gd/rollup_chat) seems not valid anymore, someone knows if there is an updated chat link.

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How to list the exposed members of a package/dir-like method in Elm?

I have been searching the official docs and existing questions and could not find any information on this - in Elm, how it would be possible to see the members/methods/variables that belong to or are exposed by a package in Elm, (such as the dir method in python), without having to dive into the source code each time?
What I want to do is get a simple list of what methods are exposed by an imported package. (So for a package like List, it should output reverse , all, any, map, etc.) I have attempted tab completion in elm repl and the elm extension available in VS code editor, and elm repl does not offer any methods such as help, doc, ?, dir, man, etc., so I have no idea where to even start. I'm wondering how everyone else does this other than pulling up the source code for each and every package they use.
I apologize for the newbie question and if I misread or have been missing anything, but I couldn't even find anything in the https://elmprogramming.com tutorial. Thanks in advance.
Nothing like this exists in Elm to do reflection over modules, unfortunately (as of 0.19.1, at least).
However, if you aren't looking to actually do this kind of thing at runtime, but rather as a convenient way of finding out for development, the elm packaging system enforces the requirement that all public functions are documented, so if you visit the package page, every public function and type will be documented there (obviously it can't enforce the content of the documentation, but at the very least it will be listed).

MetaTrader Terminal [ History Center ] section: missing data within the platform?

I have recently downloaded MT4 & MT5. In both of these platforms where the historical data section should be ( in the dropdown of the tools section ), it is missing in both and I cannot seem to find a way to access this function.
It just doesn't seem to be in the platform at all?
My intention is to carry on with my research on backtesting data.
Step 1) define the problem:
Given the text above, it seems that your MetaTrader Terminal downloads have been installed, but do not allow you to inspect the (Menu)->[Tools]->[History Center]. If this is the case, check this with Support personnel from the Broker company you have downloaded these platforms from, as there are possible ways, how some Brokers may adapt the platform, including the objected behaviour.
Step 2) explain the target behaviour:
Your initial post has mentioned that your intention is to gain access to data due to "research on backtesting data".
If this is the valid target, your goal can be achieved also by taking an MT4 platform from any other Broker, be it with or without data, and next, importing { PERIOD_M1 | PERIOD_M5 | ... }-records, via an MT4 [History Center] F2 import interface. Just enough to follow the product documentation.
If your Quantitative Modelling requires tick-based data with a Market-Access Venue "fidelity", there was no such a way so far available for an end-user to import and resample some externally collected tick-data for MetaTrader Terminal platform.
Step 3) demonstrate your research efforts + steps already performed:
This community will always welcome active members, rather than "shouting" things like "Any idea?" or "ASAP" and "I need this and that, help me!".
Showing efforts, that have been spent on solving the root cause are warmly welcome, as Stack Overflow strongly encourages members to post high quality questions, formulated in a Minimum Complete Verifiable Example of code, that can re-run + re-produce the problem under test. Using PrintScreens for UI-states are ok for your type of issue, to show the blocking state and explain the context.

How can my vhdl code and microblaze co-exist?

Well my problem stated when i had my vhdl code up and running on my Spartan-3a but needed to send and receive data from it to the pc,
I need my vhdl code , so i went for a microplaze structure , problem is I cant understand how will my vhdl code and microblaze co-exist at the same time because every time i program fpga with SDK it deletes my vhdl off the fpga and vise versa with ISE, I dont want to use custom peripherals except if this is the only solution.
Some people just tell me to just use microblaze hdl files produced by EDK, OK but theny aren't I using an unprogrrammed MicroBlaze???
And do i need to go through all of this just to be able to communicate with my vhdl code through pc(NO I CANT USE R232 since i need a speed of 56Mbit/sec)
So here is what i don't understand:
1-IF you implemented microblaze through hardware(HDL from edk to ISE) , isnt it then an un-proggrammed processor?
2-PEOPLE TELL ME i can let microblaze and my vhdl code see each other through GPIO , again how will i implement GPIO and how to connect it to both microblaze and my vhdl code , and how to program microblaze while it in hardware in this situation.
Please any help , its kinda a mess.
It is not that difficult, but unfortunately Xilinx documentation is not that clear.
What you need to do after you are done with your Microblaze code and you feel comfortable with it, is to create a new project in ISE or the one you already had, then add a new file to the project, but instead of adding a VHDL or Verilog file, you must add the system file from EDK.
After you added your XPS project into ISE, you need to do some manual work in order to make things work for you.
Here are a list of things that needs to be done:
You have to create a UCF file that includes all the constraints from EDK
You have to make sure that you have enough space inside your FPGA for both the EDK and
your own code
Synthesize and implement your design using the project in ISE.
Program your FPGA from the bit file generated by ISE
In order to communicate between the MB and your own code, you can do it in many different ways, the easiest way is to use the GPIO block from your MB, then connect those signals to your own code on your top level wrapper.
You maybe able to find some useful information on the lab document and lab material from the following Xilinx page:
enter linkXilinx EDK interface class description here
Accessing the GPIO is pretty simple, you can use the information on this page to get you started:
Reading DIP Switch with MicroBlaze
You may also find this document and related files very useful, it is not for your board, but it covers the exact same thing you are asking for:
Avnet MB tutorial document
I hope this is clear enough.

How to create documentation for instance variable and methods in Xcode?

I'd like to be able to Alt-Click an instance variable (or a method) as part of the program i created and read what it's purpose is.
The fact that Xcode is telling me the class variable is declared at - is nice but not enough. In this case i'd like to see custom text i typed to describe what an asset really is. Additionally type of the ivar would also be useful to know.
How can this be done? In this case, i wonder what exactly did i mean by assets
I specifically wonder if this information can be viewed from inside Xcode, similar to how Eclipse shows JavaDoc content.
You would need to create a documentation set for your project and install it in Xcode. appledoc can help you with this. This is a command-line tool that can generate documentation in Apple's style from specially formatted comments in your headers. You can also integrate this into your build process with a run script build phase, so that documentation is always up-to-date.
For small projects, it's usually not worth the effort though and you're probably better off just adding comments to your header files and jumping there with Cmd-click (Ctrl+Cmd+left-arrow to go back to where you came from).
You'll probably want to take a look at Apple's documentation on Documentation Sets as well as their article on generating doc sets using Doxygen. The latter is based on Xcode 3.x, so how relevant it is is somewhat questionable, but it'd be a good idea to take a look nonetheless.
That said, if you decide to use Doxygen (alternatives like HeaderDoc can be used for documentation, but I'm not sure what's available to you as far as creating doc sets goes), it looks like the main point is you'll want to throw GENERATE_DOCSET=YES into your Doxyfile (or whatever you decide to call it). After that, you'd just throw the results into ~/Library/Developer/Shared/Documentation/DocSets (according to Doxygen's documentation). I don't know whether this works in Xcode 4.x - it's worth a shot though, and it'd be nice to hear back on it.
Note: most of this was based on this answer by Barry Wark. Figure credit is due there, since I wouldn't have bothered looking into this were it not for his answer.

Porting newlib to a custom ARM setup

this is my first post, and it covers something which I've been trying to get working on and off for about a year now.
Essentially it boils down to the following: I have a copy of newlib which I'm trying to get working on an LPC2388 (an ARM7TDMI from NXP). This is on a linux box using arm-elf-gcc
The question I have is that I've been looking at a lot of the tutorials talking about porting newlib, and they all talk about the stubs (like exit, open, read/write, sbrk), and I have a pretty good idea of how to implement all of these functions. But where should I put them?
I have the newlib distribution from sources.redhat.com/pub/newlib/newlib-1.18.0.tar.gz and after poking around I found "syscalls.c" (in newlib-1.18.0/newlib/libc/sys/arm) which contains all of the stubs which I have to update, but they're all filled in with rather finished looking code (which does NOT seem to work without the crt0.S, which itself does not work with my chip).
Should I just be wiping out those functions myself, and re-writing them? Or should I write them somewhere else. Should I make a whole new folder in newlib/libc/sys with the name of my "architecture" and change the target to match?
I'm also curious if there's proper etiquette on distribution of something like this after releasing it as an open source project. I currently have a script which downloads binutils, arm-elf-gcc, newlib, and gdb, and compiles them. If I am modifying files which are in the newlib directory, should I hand a patch which my script auto-applies? Or should I add the modified newlib to the repository?
Thanks for bothering to read! Following this is a more detailed breakdown of what I'm doing.
For those who want/need more info about my setup:
I'm building a ARM videogame console based loosely on the Uzebox project ( http://belogic.com/uzebox/ ).
I've been doing all sorts of things pulling from a lot of different resources as I try and figure it out. You can read about the start of my adventures here (sparkfun forums, no one responds as I figure it out on my own): forum.sparkfun.com/viewtopic.php?f=11&t=22072
I followed all of this by reading through the Stackoverflow questions about porting newlib and saw a few of the different tutorials (like wiki.osdev.org/Porting_Newlib ) but they also suffer from telling me to implements stubs without mentioning where, who, what, when, or how!
But where should I put them?
You can put them where you like, so long as they exist in the final link. You might incorporate them in the libc library itself, or you might keep that generic, and have the syscalls as a separate target specific object file or library.
You may need to create your own target specific crt0.s and assemble and link it for your target.
A good tutorial by Miro Samek of Quantum Leaps on getting GNU/ARM development up and running is available here. The examples are based on an Atmel AT91 part so you will need to know a little about your NXP device to adapt the start-up code.
A ready made Newlib porting layer for LPC2xxx was available here, but the links ot teh files appear to be broken. The same porting layer is used in Martin Thomas' WinARM project. This is a Windows port of GNU ARM GCC, but the examples included in it are target specific not host specific.
You should only need to modify the porting layer on Newlib, and since it is target and application specific, you need not (in fact probably should not) submit your code to the project.
When I was using newlib that is exactly what I did, blew away crt0.s, syscalls.c and libcfunc.c. My personal preference was to link in the replacement for crt0.s and syscalls.c (rolled the few functions in libcfunc into the syscalls.c replacement) based on the embedded application.
I never had an interest in pushing any of that work back into the distro, so cannot help you there.
You are on the right path though, crt0.S and syscalls.c are where you want to work to customize for your target. Personally I was interested in a C library (and printf) and would primarily neuter all of the functions to return 0 or 1 or whatever it took to get the function to just work and not get in the way of linking, periodically making the file I/O functions operate on linked in data in rom/ram. Basically without replacing or modifying any other files in newlib I had a fair amount of success, so you are on the right path.