C++ is love
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Then that would be an actual garbage collector, which I'm trying to avoid. :-D Actually what I'm doing is kind of clever. I allow you to allocate a "MemoryPool" on the heap or the stack, and then allocate memory from that pool. It does not allow you to delete. However, all allocated segments are always contiguous and sequential, leading to a number of performance advantages. Instead of deleting single allocations you can freeAll() to reset/recycle the entire pool and invalidate the memory therein. It's actually quite nice for a lot of basic processing scenarios. it's just inefficient for mutable data where sizes can change - which it's not designed for.
Real programmers use butterflies
That's what AAA games use (and maybe non-AAA too, I only know what DICE did, as I worked there) - arena allocators. When a level starts, it allocates from its own "arena", and when the level is done, the arena is wiped. Lessens the risk of memory leaks and gives full control and trackability of all allocations.
Time you enjoy wasting is not wasted time - Bertrand Russel
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I'm economically agnostic. No systems devised by humans survive contact with them.
Real programmers use butterflies
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When I saw your post, I wondered how badly you were going to get flamed, given the popularity of C# on this site. I never thought this thread would stay so civilized, let alone be fairly positive. :)
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The fox knows many things, but the hedgehog knows one big thing.The day is not over yet. :rolleyes: :laugh:
M.D.V. ;) If something has a solution... Why do we have to worry about?. If it has no solution... For what reason do we have to worry about? Help me to understand what I'm saying, and I'll explain it better to you Rating helpful answers is nice, but saying thanks can be even nicer.
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Okay that's fair, except I can't think of much I can't get to in C++ with the right massaging of the compiler. I can manually build vtbls, i can make call stack frames myself, typically, I can even drop to inline assembly if I really want. So I see it more as giving you more tools than ASM. I don't think it takes anything away.
Real programmers use butterflies
Make your own vtbls and call stack frames? Do tell. When do you find this useful? My naughtiest code changed an object's class at runtime by changing its vptr. The two classes in question had a common base class and owned other objects, so this avoided a messy deep copy and fixing pointers to the morphed object. I wonder how many OO languages could do that.
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The fox knows many things, but the hedgehog knows one big thing. -
Some of the references warn against its use. So far as I can tell, it's based upon usage and gotcha's that are common in C - in other words, C is for grownup who take responsibility for their actions. Simply put - know what you're doing when you do it. Don't free() it - well, duh! That's the point of using it. Beware of stack overflows. Always keep your wits about you with memory usage. Don't use in recursive functions or loops. In a loop, index the allocations into an array of pointers, or, if you want to reuse the same one, allocate it before the loop . . . just like the other memory functions. Seems standard enough - for the grownups in the room
"The difference between genius and stupidity is that genius has its limits." - Albert Einstein
"If you are searching for perfection in others, then you seek disappointment. If you seek perfection in yourself, then you will find failure." - Balboos HaGadol Mar 2010
Quote:
Some of the references warn against its use. Simply put - know what you're doing when you do it. Don't free() it - well, duh! That's the point of using it. Beware of stack overflows. Always keep your wits about you with memory usage. Don't use in recursive functions or loops. In a loop, index the allocations into an array of pointers, or, if you want to reuse the same one, allocate it before the loop . . . just like the other memory functions. Seems standard enough - for the grownups in the room
Don't use alloca(), it's not part of the C standard.
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GitHub - codewitch-honey-crisis/MemoryPool: Small fixed size sequential memory pool allocators for constrained memory environments[^] :laugh:
Real programmers use butterflies
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Quote:
Some of the references warn against its use. Simply put - know what you're doing when you do it. Don't free() it - well, duh! That's the point of using it. Beware of stack overflows. Always keep your wits about you with memory usage. Don't use in recursive functions or loops. In a loop, index the allocations into an array of pointers, or, if you want to reuse the same one, allocate it before the loop . . . just like the other memory functions. Seems standard enough - for the grownups in the room
Don't use alloca(), it's not part of the C standard.
I read that too; mentioned it somewhere in this thread. That would be like "Don't Use that Graphics Library - it's not part of the C Standard".*
"The difference between genius and stupidity is that genius has its limits." - Albert Einstein
"If you are searching for perfection in others, then you seek disappointment. If you seek perfection in yourself, then you will find failure." - Balboos HaGadol Mar 2010
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I read that too; mentioned it somewhere in this thread. That would be like "Don't Use that Graphics Library - it's not part of the C Standard".*
"The difference between genius and stupidity is that genius has its limits." - Albert Einstein
"If you are searching for perfection in others, then you seek disappointment. If you seek perfection in yourself, then you will find failure." - Balboos HaGadol Mar 2010
Only use code that runs as expected on the [DeathStation 9000](https://enacademic.com/dic.nsf/enwiki/2748465)!
Freedom is the freedom to say that two plus two make four. If that is granted, all else follows. -- 6079 Smith W.
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Would you mind if I gave you a small critique on that code?
go ahead. my C++ is rusty so I'm sure there's stuff to be improved.
Real programmers use butterflies
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Make your own vtbls and call stack frames? Do tell. When do you find this useful? My naughtiest code changed an object's class at runtime by changing its vptr. The two classes in question had a common base class and owned other objects, so this avoided a messy deep copy and fixing pointers to the morphed object. I wonder how many OO languages could do that.
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The fox knows many things, but the hedgehog knows one big thing.The call stack frames can be useful for doing things like method logging frameworks The vtbl manipulation is useful if your making a library to do hardcore COM interop
Real programmers use butterflies
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honey the codewitch wrote:
I'm economically agnostic
that is a copout, and you know it. ;)
It's not. It's the truth. I'm married to a communist, but that doesn't make me one.
Real programmers use butterflies
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Only use code that runs as expected on the [DeathStation 9000](https://enacademic.com/dic.nsf/enwiki/2748465)!
Freedom is the freedom to say that two plus two make four. If that is granted, all else follows. -- 6079 Smith W.
(fill in clever retort of your choice) Ravings en masse^
"The difference between genius and stupidity is that genius has its limits." - Albert Einstein
"If you are searching for perfection in others, then you seek disappointment. If you seek perfection in yourself, then you will find failure." - Balboos HaGadol Mar 2010
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go ahead. my C++ is rusty so I'm sure there's stuff to be improved.
Real programmers use butterflies
Not much improvement, just a few observations: 1. Identifiers starting with underscores are reserved. If you use them then your program is non-conforming for no good reason. 2. The comparison against capacity in both the static and dynamic classes result in never being able to use the last byte of the pool: The "used()>=capacity" should be "used()>capacity". To test it instantiate a pool of 10 bytes and allocate 6. The (capacity() - used()) is then 4, but a further allocation of 4 fails. A further allocation of 3, on the other hand, succeeds and (capacity() - used()) is then 1. 3. The static pool could benefit from a #warning directive when C is too large. Right now a 8MB C when instantiating it (1024 * 1024 * 8) would almost certainly overflow the stack, and 8MB is not a lot of memory.
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Not much improvement, just a few observations: 1. Identifiers starting with underscores are reserved. If you use them then your program is non-conforming for no good reason. 2. The comparison against capacity in both the static and dynamic classes result in never being able to use the last byte of the pool: The "used()>=capacity" should be "used()>capacity". To test it instantiate a pool of 10 bytes and allocate 6. The (capacity() - used()) is then 4, but a further allocation of 4 fails. A further allocation of 3, on the other hand, succeeds and (capacity() - used()) is then 1. 3. The static pool could benefit from a #warning directive when C is too large. Right now a 8MB C when instantiating it (1024 * 1024 * 8) would almost certainly overflow the stack, and 8MB is not a lot of memory.
1. I thought they were only reserved for globals. I stand corrected. 2. Good catch. 3. The static pool can and often is declared as a global, making it heap/not stack, which is where it's primarily designed to go. DynamicMemoryPool is probably a better choice if you need a locally scoped pool because it always allocates from the heap. Thanks!
Real programmers use butterflies
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W∴ Balboos, GHB wrote:
I'd presume it used the stack for memory.
Yep, exactly. I had the habit of making objects "stackable" whenever possible, for example strings had fixed size straight into the struct, so the whole object was a single contiguous dataspace easily allocatable in the stack and passed around with a memcpy. Of course it isn't alwasy the best option but I like it when it is.
GCS d--(d+) s-/++ a C++++ U+++ P- L+@ E-- W++ N+ o+ K- w+++ O? M-- V? PS+ PE- Y+ PGP t+ 5? X R+++ tv-- b+(+++) DI+++ D++ G e++ h--- r+++ y+++* Weapons extension: ma- k++ F+2 X
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It's not. It's the truth. I'm married to a communist, but that doesn't make me one.
Real programmers use butterflies
honey the codewitch wrote:
I'm married to a communist
I shudder at the thought.
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honey the codewitch wrote:
I'm married to a communist
I shudder at the thought.
He's nice. He likes to share, and has a fondness for bureaucracy which I find in explicable. I'm pretty much the antithesis to that so we balance. Still, to each their own.
Real programmers use butterflies
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I had a programmer who was notorious for declaring char somestr[256]; and RETURNING somestr out of the function to be used by others. "But it runs fine in the debugger" was his last refrain... LOL
declaring it on the stack? ouch. I only return char*s from functions if I'm using some kind of memory management scheme that allows for it. Unless you implement one C and C++ ... doesn't. I can't judge people too badly though, considering I just got schooled on using leading underscores in my local member names (a habit I picked up from C#) But still, you should understand scoping if you're going to get paid to code in the thing.
Real programmers use butterflies
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(fill in clever retort of your choice) Ravings en masse^
"The difference between genius and stupidity is that genius has its limits." - Albert Einstein
"If you are searching for perfection in others, then you seek disappointment. If you seek perfection in yourself, then you will find failure." - Balboos HaGadol Mar 2010
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W∴ Balboos, GHB wrote:
(fill in clever retort of your choice)
Amazon.co.uk : glass retort](https://www.amazon.co.uk/s?k=glass+retort&hvadid=80401819685055&hvbmt=be&hvdev=c&hvqmt=e&tag=mh0a9-21&ref=pd_sl_7xksutbpbn_e)[^]
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Only use code that runs as expected on the [DeathStation 9000](https://enacademic.com/dic.nsf/enwiki/2748465)!
Freedom is the freedom to say that two plus two make four. If that is granted, all else follows. -- 6079 Smith W.
