Are there any instructions on how to use this code?

[ammonc]

It looks like I want to get a copy of LLVM 2.5 and whatever version of clang is compatible with that and add in this code in the LLVM tree...

Are there any other details on how to do this?

BTW, thanks for preserving the code from c-to-verilog.com

[udif]

The last time I touched this was a few years ago. My original aim was to gradually make changes and move ahead one LLVM version at a time since I was afraid that migrating to a much more recent LLVM version would make too many failures and would be hard to fix.
At the time, I was able to compile it with my then contemporary environment. However, I haven't done much with the code.

Now that you have asked, I tried to recreate what I was able to achieve back then.

The most important part to remember is that this directory needs to be installed inside LLVM and compiled as part of it.
I think you need to get a soft link pointing from $(LLVM)/lib/Target/Verilog to your 'Verilog' directory from the git repository.

As for compiling and running the whole thing, I was able to compile it by installing the g++-4.4 package for my debian 7 system, then in $LLVM I did:

./configure CXX=g++-4.4

make CXXFLAGS='-fpermissive'
(without this flag, you'll get errors due to const pointer being cast to non-const pointer).

You might need gcc-4.4 as well (and if you do, then add CFLAGS='-fpermissive' as well).

make install

Assuming you didn't override the install directory by supplying a --prefix arg to ./configure, then you'll find the whole stuff spread under /usr/local.
Now do the following to add the Verilog stuff since the install make rules don't install it:
cp -p $LLVM/Release/lib/Synth /usr/local/lib
This is because we haven't really fixed the configuration files to pick up the Verilog generator as well.

At this point, after playing with the vcc.sh script, I got internal failures from some llvm tools, so I haven't been able to progress further.

You might want to take a look at https://github.com/cgerum/c2verilog which also mirrored the web site, but progressed further than me by porting to llvm-2.9 his port also seems to be abandoned.

Another direction to follow is to use the llvm-gcc-4.2 front end from http://llvm.org/releases/download.html#2.5
and consult the documentation at http://llvm.org/releases/2.5/docs/GettingStarted.html#environment

[ammonc]

@udif, Thanks so much for your quick response. It looks like that fork ported to 2.9 and got a simple 32-bit signed adder to compile to verilog. I will try to follow your instructions on that port and see if I can reproduce that simple example as well. (And then move on to the obviously more complex code I have in mind).

Again, much appreciation for your help.

[udif]

Please note that I updated one line above:
cp -p $LLVM/Release/lib/Synth /usr/local/lib
The original line didn't show the '*' because these are used by markdown and needed to be escaped.

[ammonc]

Thanks. I'll give it a try. Right now this is my top prospect.

[udif]

OK, I have a new CentOS 7.1 test system.
I downloaded gcc4.2.4 and successfully compiled it.
I ran into two problems:
https://gcc.gnu.org/ml/gcc-help/2014-01/msg00052.html
https://gcc.gnu.org/ml/gcc/2013-07/msg00075.html
I ended up solving both, unfortunately I didn't write down the order, but it involved installing 32-bit development libraries as well as using --disable-multilib

sudo yum install glibc-devel.i686
./configure --disable-multilib
make
make install

At this point I was able to compile LLVM-2.5 with the Verilog soft link into c2verilog.
cd ~/llvm-2.5/lib/Target
ln -s -n ~/ctoverilog/Verilog Verilog

Next step is apparently to install the gcc front end for LLVM that appears in the LLVM 2.5 download page.
I'll keep a log here, and eventually update the build instructions.

[udif]

Further updates - I build llvm-gcc successfully.
I also seem to have problems now rebuilding LLVM 2.5 with C2verilog using soft links. for some reason the make process resolves the location of the soft link into the target directory, and as a result can't find Makefile.common which is referenced via ../../.. relative to $LLVM/lib/Target/Verilog
I solved this by copying the Verilog directory instead of soft linking it.
After this I managed to run vcc.sh and compile a dummy c test:
a.c:
int a(int x) { return x+1; }

I'll update the README with detailed build instructions, but it will take a day or two.

[udif]

I updated the README file with build instructions and restructured the repository in a way that lets us clone directly into LLVM, yet keep the current makefile.
I'm not closing this yet, because I tried replicating my work from scratch following the README.md instruction and have ran into problems at the linking stage. I'm still looking into this. When I'm done, I'll update the README.md and close this issue.

[rknath]

No issues now. I got it work. thanks

[ammonc]

I am trying to follow your REAME.md instructions. I am using gcc 4.2.2 instead of 4.2.4

I was able to build LLVM but when I try to build the gcc frontend this is what I get:

Any ideas?

gcc -c -g -DIN_GCC -W -Wall -Wwrite-strings -Wstrict-prototypes -Wmissing-prototypes -fno-common -DHAVE_CONFIG_H -DGENERATOR_FILE -I. -Ibuild -I../../llvm-gcc4.2-2.5.source/gcc -I../../llvm-gcc4.2-2.5.source/gcc/build -I../../llvm-gcc4.2-2.5.source/gcc/../include -I../../llvm-gcc4.2-2.5.source/gcc/../libcpp/include -I../../llvm-gcc4.2-2.5.source/gcc/../libdecnumber -I../libdecnumber -I/nfs/fm/disks/fm_eig_00009/ajchrist/ctoverilog_env/llvm-2.5/include -DENABLE_LLVM -I/nfs/fm/disks/fm_eig_00009/ajchrist/ctoverilog_env/llvm-2.5/include -D_DEBUG -D_GNU_SOURCE -D__STDC_LIMIT_MACROS -D__STDC_CONSTANT_MACROS -DLLVM_VERSION_INFO='"2.5"' -o build/gencondmd.o build/gencondmd.c
../../llvm-gcc4.2-2.5.source/gcc/config/i386/i386.md:5132: error: 'TARGET_64BIT' undeclared here (not in a function)
../../llvm-gcc4.2-2.5.source/gcc/config/i386/i386.md:5140: warning: missing initializer
../../llvm-gcc4.2-2.5.source/gcc/config/i386/i386.md:5140: warning: (near initialization for 'insn_conditions[0].value')
../../llvm-gcc4.2-2.5.source/gcc/config/i386/i386.md:4926: warning: missing initializer
../../llvm-gcc4.2-2.5.source/gcc/config/i386/i386.md:4926: warning: (near initialization for 'insn_conditions[1].value')
../../llvm-gcc4.2-2.5.source/gcc/config/i386/i386.md:9844: error: 'TARGET_80387' undeclared here (not in a function)
../../llvm-gcc4.2-2.5.source/gcc/config/i386/i386.md:9844: error: 'TARGET_SSE2' undeclared here (not in a function)
../../llvm-gcc4.2-2.5.source/gcc/config/i386/i386.md:9846: warning: missing initializer
../../llvm-gcc4.2-2.5.source/gcc/config/i386/i386.md:9846: warning: (near initialization for 'insn_conditions[3].value')
../../llvm-gcc4.2-2.5.source/gcc/config/i386/i386.md:4237: error: 'TARGET_SSE' undeclared here (not in a function)
../../llvm-gcc4.2-2.5.source/gcc/config/i386/i386.md:4239: warning: missing initializer
../../llvm-gcc4.2-2.5.source/gcc/config/i386/i386.md:4239: warning: (near initialization for 'insn_conditions[4].value')
../../llvm-gcc4.2-2.5.source/gcc/config/i386/sse.md:2855: error: 'TARGET_SSE4_1' undeclared here (not in a function)

[udif]

Sorry for the late reply, summertime and all that.

the VM that hosted my work on this is currently not booting (some issues
with having conflicting libs on /usr/local and having it on the
LD_LIBRARY_PATH or something like that). Once I manage to boot into single
user mode (Centos), I'll take a look at your problem.

As a side note, I have a private branch that was not pushed yet with the
necessary changes for 2.7. The only problem with it are related to the fact
that this was originally built as a standalone shared lib for 2.6, and some
changes in 2.7 broke it, and I couldn't find an example of an LLVM codegen
that compiles as a shared lib. Keeping it as a shared lib eases development
and precludes the need for fixing the global makefiles.

On Thu, Aug 6, 2015 at 4:47 AM, Ammon Christiansen <notifications@github.com

wrote:

I am trying to follow your REAME.md instructions. I am using gcc 4.2.2
instead of 4.2.4

I was able to build LLVM but when I try to build the gcc frontend this is
what I get:

Any ideas?

gcc -c -g -DIN_GCC -W -Wall -Wwrite-strings -Wstrict-prototypes
-Wmissing-prototypes -fno-common -DHAVE_CONFIG_H -DGENERATOR_FILE -I.
-Ibuild -I../../llvm-gcc4.2-2.5.source/gcc
-I../../llvm-gcc4.2-2.5.source/gcc/build
-I../../llvm-gcc4.2-2.5.source/gcc/../include
-I../../llvm-gcc4.2-2.5.source/gcc/../libcpp/include
-I../../llvm-gcc4.2-2.5.source/gcc/../libdecnumber -I../libdecnumber
-I/nfs/fm/disks/fm_eig_00009/ajchrist/ctoverilog_env/llvm-2.5/include
-DENABLE_LLVM
-I/nfs/fm/disks/fm_eig_00009/ajchrist/ctoverilog_env/llvm-2.5/include
-D_DEBUG -D_GNU_SOURCE -D__STDC_LIMIT_MACROS -D__STDC_CONSTANT_MACROS
-DLLVM_VERSION_INFO='"2.5"' -o build/gencondmd.o build/gencondmd.c
../../llvm-gcc4.2-2.5.source/gcc/config/i386/i386.md:5132: error:
'TARGET_64BIT' undeclared here (not in a function)
../../llvm-gcc4.2-2.5.source/gcc/config/i386/i386.md:5140: warning:
missing initializer
../../llvm-gcc4.2-2.5.source/gcc/config/i386/i386.md:5140: warning: (near
initialization for 'insn_conditions[0].value')
../../llvm-gcc4.2-2.5.source/gcc/config/i386/i386.md:4926: warning:
missing initializer
../../llvm-gcc4.2-2.5.source/gcc/config/i386/i386.md:4926: warning: (near
initialization for 'insn_conditions[1].value')
../../llvm-gcc4.2-2.5.source/gcc/config/i386/i386.md:9844: error:
'TARGET_80387' undeclared here (not in a function)
../../llvm-gcc4.2-2.5.source/gcc/config/i386/i386.md:9844: error:
'TARGET_SSE2' undeclared here (not in a function)
../../llvm-gcc4.2-2.5.source/gcc/config/i386/i386.md:9846: warning:
missing initializer
../../llvm-gcc4.2-2.5.source/gcc/config/i386/i386.md:9846: warning: (near
initialization for 'insn_conditions[3].value')
../../llvm-gcc4.2-2.5.source/gcc/config/i386/i386.md:4237: error:
'TARGET_SSE' undeclared here (not in a function)
../../llvm-gcc4.2-2.5.source/gcc/config/i386/i386.md:4239: warning:
missing initializer
../../llvm-gcc4.2-2.5.source/gcc/config/i386/i386.md:4239: warning: (near
initialization for 'insn_conditions[4].value')
../../llvm-gcc4.2-2.5.source/gcc/config/i386/sse.md:2855: error:
'TARGET_SSE4_1' undeclared here (not in a function)

—
Reply to this email directly or view it on GitHub
#1 (comment).