Robot Game: Comparing 6502 C, Assembly, and Forth
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Re: Robot Game: Comparing 6502 C, Assembly, and Forth
#2This nicely provides empircal evidence on the slowdown of using Forth, which seems to be around 10 to 20 times slower than optimized assembly. I was initially surprised by how poorly Forth performed on all counts of speed, memory usage and development time. For something as complex as a game the lack of a type system and postfix nature make Forth quite unsuitable.
When I use Forth, it's often for high-level applications[0] with the performance critical words written in assembly. So this keeps the complexity relatively low as opposed to writing the whole thing in Forth.
[0] https://github.com/siraben/zkeme80/blob/master/src/bootstrap...
Re: Robot Game: Comparing 6502 C, Assembly, and Forth
#3This nicely provides empircal evidence on the slowdown of using Forth, which seems to be around 10 to 20 times slower than optimized assembly. I was initially surprised by how poorly Forth performed on all counts of speed, memory usage and development time. For something as complex as a game the lack of a type system and postfix nature make Forth quite unsuitable. When I use Forth, it's often for high-level applicati…
I think the writer use case takes no benefit from Forth. He already has some code and is trying to translate and optimize it. In this case, none of the advantages of Forth matter because he is not doing the development interactively. He was also tied to an existing code architecture that is alien to Forth. A Forth programmer starting from scratch would certainly design things in a way that makes more sense to Forth. Instead, his design clearly benefits a C implementation and goes against the way Forth code is structured.
Re: Robot Game: Comparing 6502 C, Assembly, and Forth
#4Unfortunately, it seems that for all practical purposes, and as much as we love it, 6502 in all its (still existing) incarnations is all but dead.Even MIPS has been dying, albeit slowly and painfully. The unpleasant truth is that as we now all know that ARM is currently the only sane choice for a hobbyist project (see, for example, Color Maximite 2), and we can only hope that RISC-V will someday replace it in the hands of CPU aficionados, but in the times when for a few pennies we can have an 8-pin ARM microcontroller, this is a no-brainer. (ESP32, being quite popular, due to its highly integrated nature and the focus on IoT is a somewhat different proposition.)
Re: Robot Game: Comparing 6502 C, Assembly, and Forth
#5This nicely provides empircal evidence on the slowdown of using Forth, which seems to be around 10 to 20 times slower than optimized assembly. I was initially surprised by how poorly Forth performed on all counts of speed, memory usage and development time. For something as complex as a game the lack of a type system and postfix nature make Forth quite unsuitable. When I use Forth, it's often for high-level applicati…
Yes, FORTH is an elegant alternative to BASIC on very small systems, not something you should expect high performance from.
Re: Robot Game: Comparing 6502 C, Assembly, and Forth
#6This nicely provides empircal evidence on the slowdown of using Forth, which seems to be around 10 to 20 times slower than optimized assembly. I was initially surprised by how poorly Forth performed on all counts of speed, memory usage and development time. For something as complex as a game the lack of a type system and postfix nature make Forth quite unsuitable. When I use Forth, it's often for high-level applicati…
If you program Forth like it's C, and then use a non-optimizing compiler, you're going to have a bad time (e.g. 10/20x slowdowns).
I've written Forth compilers that generated output that was ~25% slower than optimized assembly, without putting that much work into it. There are companies that will sell you a much better compiler [0], at prices even approachable to hobbyists.
[0] - https://www.mpeforth.com/software/pc-systems/vfx-forth-for-l...
Re: Robot Game: Comparing 6502 C, Assembly, and Forth
#7This nicely provides empircal evidence on the slowdown of using Forth, which seems to be around 10 to 20 times slower than optimized assembly. I was initially surprised by how poorly Forth performed on all counts of speed, memory usage and development time. For something as complex as a game the lack of a type system and postfix nature make Forth quite unsuitable. When I use Forth, it's often for high-level applicati…
Yes, FORTH is an elegant alternative to BASIC on very small systems, not something you should expect high performance from.
To mirror asguy's comment, this only tells us about the performance of this particular FORTH engine, it doesn't tell us about the performance inherit to FORTH (which of course doesn't exist, it's down to the engine).
Whether anyone has made a sophisticated optimising FORTH for 6502, I don't know.
Re: Robot Game: Comparing 6502 C, Assembly, and Forth
#8Interesting that OP ignored ca65 and went to NASM for the second assemble option especially since they were already using cc65.
Nice use of High Level Assembly with the macros!
Re: Robot Game: Comparing 6502 C, Assembly, and Forth
#9This nicely provides empircal evidence on the slowdown of using Forth, which seems to be around 10 to 20 times slower than optimized assembly. I was initially surprised by how poorly Forth performed on all counts of speed, memory usage and development time. For something as complex as a game the lack of a type system and postfix nature make Forth quite unsuitable. When I use Forth, it's often for high-level applicati…
I think the writer use case takes no benefit from Forth. He already has some code and is trying to translate and optimize it. In this case, none of the advantages of Forth matter because he is not doing the development interactively. He was also tied to an existing code architecture that is alien to Forth. A Forth programmer starting from scratch would certainly design things in a way that makes more sense to Forth.…
OP here. This is a really interesting point. My strategy was to keep the highest level functions/words like DrawTile or DrawMenu while writing the underlying Forth and subwords from scratch focusing on performance. Do you have any suggestions that would make "more sense to Forth" as you say?
Re: Robot Game: Comparing 6502 C, Assembly, and Forth
#10I don't know Forth on the 6502 but I think the statement that STC is the fastest form of Forth is not always true. But it will lead to larger programs.