On Friday, 23 June 2017 at 19:03:01 UTC, FoxyBrown wrote:
Hi,
I will be developing some hardware and software that will need
to be portable across a multitude of systems.
At first, I will develop some of the non-specific
infrastructural code base on windows for convenience. These
involve the GUI, overall structure, etc.
I think will need to move in to more mobile aspects such as the
android and Raspberry Pi which will allow me to start to
integrate and work with the future hardware based parts of this
system.
At this point I am in the setup stages that will organize and
formulate a proper plan of action. I am aware that D works for
Windows/Linux/Mac and has some Raspberry Pi and android/arm
support with very little FPGA/ASIC/DSP/uC support.
I hope, by the time that I get in to the hardware layers that D
will have advanced further down the line on them.
My understanding is that DMD is only applicable for the 3 main
platforms, and this is fine for now as that is where I'll
start. LDC is starting to progress on ARM/android and I have
seen someone write a to use D on FPGA through a transformation
process. Some work has been done with some lower level uC's
such as the PIC and ARM processors.
Now that GDC is in the works, I assume that will open up even
more doors. Because this is a long term project(10+ years) and
involves many different systems, subsystems, architectures, and
so forth, organization is key for success. The problem I have
with the choice of D over C/C++, at the moment, is in it's
knowledge base. Most of the advancements for the different
platforms are done by individuals with their own unique goals
and motivations in mind. There is very little organized
structure to the overall development. Finding information for
specific aspects and requirements involves hunting down the
appropriate information. Usually it is forum posts and link
fishing, usually outdated. Structured documentation is key for
efficient and successful progress, which I find D to be lacking
in. While library functionality is documented and adequate, the
architectural issues and development is not.
Is there any hope of seeing a unified structured interface to
the different platforms that D is starting to be developed on
rather than having to hunt and peck for the answers?
If not, may I suggest, at a minimum, some type of hierarchy
based solution that involves all the major design applications
of D with the ability to cross-reference, date, comment, and
modify? A sort of wiki but with a bit more hierarchical
structure.
D
Cross-Platform
Compilers
...
GDC
...
Library
...
...
Windows
Compiler
...
Compiling
...
...
Library
...
Compiling
...
Documentation
...
Wi32 API
...
Problems
...
Functions
...
Misc
...
Uncategorized
...
...
...
...
DSP
...
Progress
...
...
The idea is that one can delve in to the hierarchy and find
whatever info they want or add to it if it is not there so that
someone else can find it. At some point, most of what D can do
is found in the hierarchy, which, as we all know, only requires
around O(log2(n)) search time(rather than O(n^m) for googling
topics and link fishing). At some point, this hierarchy
becomes very efficient at representing the information we all
are searching for rather than a flat random access type of
list. The point is to design such an interface and let users
like me fill it out and as time goes on, finding relevant
information becomes quicker and quicker. For proper design,
meta-information must be used to it's fullest. (Tags, date
stamping, ratings, relevancy, cross-references, etc)
Or, perhaps, we already have something this powerful in the
works?
The ldc wiki page has a rudimentary version of what you're
looking for, listing all platforms worked on and some idea of how
well they're supported:
https://wiki.dlang.org/LDC
Dmd will likely never target the vast majority of the platforms
you list, so it will depend on the gdc and ldc teams doing it.
Also, I'm looking at submitting a pull with my last ldc CMake
patch to cross-compile the stdlib for Android/ARM and
generalizing it for other platforms too:
https://gist.github.com/joakim-noah/d74af3cf1355492557a9c56ef1bf2636
Once that's in, building a cross-compiled stdlib for several
platforms should be as simple as setting some flags with the
location of a C cross-compiler and any C/linker flags you need,
then running the same cmake/make combo that you use to build a
native stdlib today.
No modifications are needed to ldc itself for well-supported
platforms, as ldc is always a cross-compiler by default. For
example, kinke used the new llvm linker, lld, to cross-compile
Windows/x64 binaries from linux/x64 by using the stock ldc
compiler. The instructions for how he did it are linked from the
changelog for the latest ldc 1.3 beta2:
https://github.com/ldc-developers/ldc/pull/2142#issuecomment-304472412
Finally, the latest ldc 1.3 betas for the first time include the
llvm code-generation target backends for various other CPUs, like
ARM or PowerPC, whereas before ldc only bothered to compile in
the x86/x64 backends, as those were the only stdlibs it
distributed:
[joakim@localhost ~]$ ./ldc2-1.3.0-beta2-linux-x86_64/bin/ldc2
--version
LDC - the LLVM D compiler (1.3.0-beta2):
based on DMD v2.073.2 and LLVM 4.0.0
built with LDC - the LLVM D compiler (1.3.0-beta2)
Default target: x86_64-unknown-linux-gnu
Host CPU: broadwell
http://dlang.org - http://wiki.dlang.org/LDC
Registered Targets:
aarch64 - AArch64 (little endian)
aarch64_be - AArch64 (big endian)
arm - ARM
arm64 - ARM64 (little endian)
armeb - ARM (big endian)
ppc32 - PowerPC 32
ppc64 - PowerPC 64
ppc64le - PowerPC 64 LE
thumb - Thumb
thumbeb - Thumb (big endian)
x86 - 32-bit X86: Pentium-Pro and above
x86-64 - 64-bit X86: EM64T and AMD64
Not very useful right now unless you're doing bare-metal
programming on those newly added architectures, because the
cross-compiled stdlibs are not included and there's no easy way
to generate them, but we could also put out separate tarfiles
with the cross-compiled stdlibs (separated only to save space in
the compiler download for those who don't want them), just as
kinke used the ldc stdlib compiled for Windows/x64 on linux/x64
when cross-compiling.
Just last night, I was thinking about some easy way to let ldc
users cross-compile the stdlib themselves from the regular ldc
download, and I thought of doing it with dub, the D package
manager, since we now distribute dub alongside ldc. However, I
don't know how feasible this is with dub, needs to be looked into.
