The Visual Studio port at this time is experimental. It is suitable for use only if you are writing your own compiler front end or otherwise have a need to dynamically generate machine code. The JIT and interpreter are - functional, but it is currently not possible to directly generate an - executable file. You can do so indirectly by using the C back end.
- -To emphasize, there is no C/C++ front end currently available. llvm-gcc - is based on GCC, which cannot be bootstrapped using VC++. Eventually there - should be a llvm-gcc based on Cygwin or Mingw that is usable. There is also - the option of generating bytecode files on Unix and copying them over to - Windows. But be aware the odds of linking C++ code compiled with llvm-gcc - with code compiled with VC++ is essentially zero.
+ functional, but it is currently not possible to generate assembly code which + is then assembled into an executable. You can indirectly create executables + by using the C back end. + +To emphasize, there is no C/C++ front end currently available. + llvm-gcc is based on GCC, which cannot be bootstrapped using VC++. + Eventually there should be a llvm-gcc based on Cygwin or MinGW that + is usable. There is also the option of generating bitcode files on Unix and + copying them over to Windows. But be aware the odds of linking C++ code + compiled with llvm-gcc with code compiled with VC++ is essentially + zero.
The LLVM test suite cannot be run on the Visual Studio port at this time.
-Most of the tools build and work. llvm-db does not build at this - time. bugpoint does build, but does not work. +
Most of the tools build and work. bugpoint does build, but does + not work. The other tools 'should' work, but have not been fully tested.
Additional information about the LLVM directory structure and tool chain can be found on the main Getting Started - page.
+ page. @@ -86,7 +86,7 @@It is strongly encouraged that you get the latest version from Subversion as +changes are continually making the VS support better.
+ @@ -151,8 +178,8 @@Any system that can adequately run Visual Studio .NET 2003 is fine. The - LLVM source tree and object files, libraries and executables will consume +
Any system that can adequately run Visual Studio .NET 2005 SP1 is fine. + The LLVM source tree and object files, libraries and executables will consume approximately 3GB.
You will need Visual Studio .NET 2003. Earlier versions cannot open the - solution/project files. The VS 2005 beta can, but will migrate these files - to its own format in the process. While it should work with the VS 2005 - beta, there are no guarantees and there is no support for it at this time.
+You will need Visual Studio .NET 2005 SP1 or higher. The VS2005 SP1 + beta and the normal VS2005 still have bugs that are not completely + compatible. VS2003 would work except (at last check) it has a bug with + friend classes that you can work-around with some minor code rewriting + (and please submit a patch if you do). Earlier versions of Visual Studio + do not support the C++ standard well enough and will not work.
+ +You will also need the CMake build + system since it generates the project files you will use to build with.
-You will also need several open source packages: bison, flex, and sed. - These must be installed in llvm/win32/tools. These can be found at - http://gnuwin32.sourceforge.net/ - . Bison prefers that m4 be in the path. You must add it to the Visual - Studio configuration under the menu Options -> Projects -> VC++ - Directories. Alternatively, you can set the environment variable M4 - to point to m4 executable.
++ Do not install the LLVM directory tree into a path containing spaces (e.g. + C:\Documents and Settings\...) as the configure step will fail.
- -
-
-If you have the LLVM distribution, you will need to unpack it before you -can begin to compile it. LLVM is distributed as a set of two files: the LLVM -suite and the LLVM GCC front end compiled for your platform. There is an -additional test suite that is optional. Each file is a TAR archive that is -compressed with the gzip program. The WinZip program can also unpack this -archive. Only the LLVM suite is usable with Visual Studio. -
+This is the top level directory of the LLVM source tree.
The files are as follows: -
This is the top level directory of the LLVM object tree (i.e. the + tree where object files and compiled programs will be placed. It is + fixed at SRC_ROOT/win32).
If you have access to our CVS repository, you can get a fresh copy of -the entire source code. Note that significant progress has been made on the -Visual Studio port since 1.4 was released. All you need to do is check it out -from CVS as follows:
- -This will create an 'llvm' directory in the current -directory and fully populate it with the LLVM source code, Makefiles, -test directories, and local copies of documentation files.
- -If you want to get a specific release (as opposed to the most recent -revision), you can specify a label. The following releases have the following -label:
- -If the main CVS server is overloaded or inaccessible, you can try one of -these user-hosted mirrors:
- - -The object files are placed under OBJ_ROOT/Debug for debug builds and OBJ_ROOT/Release for release (optimized) builds. These include - both executables and libararies that your application can link against. + both executables and libararies that your application can link against.
The files that configure would create when building on Unix are created by the Configure project and placed in OBJ_ROOT/llvm. You application must have OBJ_ROOT in its include - search path just before SRC_ROOT/include. + search path just before SRC_ROOT/include.
- #include <stdio.h>
- int main() {
- printf("hello world\n");
- return 0;
- }
- Next, compile the C file into a LLVM bytecode file:
-% llvm-gcc hello.c -o hello
- -Note that you should have already built the tools and they have to be - in your path, at least gccas and gccld.
- -This will create two result files: hello and - hello.bc. The hello.bc is the LLVM bytecode that - corresponds the the compiled program and the library facilities that it - required. hello is a simple shell script that runs the bytecode - file with lli, making the result directly executable. Note that - all LLVM optimizations are enabled by default, so there is no need for a - "-O3" switch.
+First, create a simple C file, name it 'hello.c':
+ +
+#include <stdio.h>
+int main() {
+ printf("hello world\n");
+ return 0;
+}
+Next, compile the C file into a LLVM bitcode file:
+ ++% llvm-gcc -c hello.c -emit-llvm -o hello.bc ++
This will create the result file hello.bc which is the LLVM + bitcode that corresponds the the compiled program and the library + facilities that it required. You can execute this file directly using + lli tool, compile it to native assembly with the llc, + optimize or analyze it further with the opt tool, etc.
Note: while you cannot do this step on Windows, you can do it on a - Unix system and transfer hello.bc to Windows.
Run the program. To make sure the program ran, execute the - following command:
+Run the program using the just-in-time compiler:
-% lli hello.bc
+% lli hello.bc ++
Note: this will only work for trivial C programs. Non-trivial programs + (and any C++ program) will have dependencies on the GCC runtime that + won't be satisfied by the Microsoft runtime libraries.
Use the llvm-dis utility to take a look at the LLVM assembly code:
-% llvm-dis < hello.bc | less
+% llvm-dis < hello.bc | more ++
Compile the program to C using the LLC code generator:
-Compile the program to native assembly using the LLC code - generator:
++% llc -march=c hello.bc ++
% llc hello.bc -o hello.s
+Compile to binary using Microsoft C:
-Assemble the native assembly language file into a program:
++% cl hello.cbe.c ++
Not currently possible, but eventually will use NASMW.
+Note: this will only work for trivial C programs. Non-trivial programs + (and any C++ program) will have dependencies on the GCC runtime that won't + be satisfied by the Microsoft runtime libraries.
Execute the native code program:
-% ./hello.native
+% hello.cbe.exe ++
If you are having problems building or using LLVM, or if you have any other general questions about LLVM, please consult the Frequently Asked Questions page.
@@ -407,10 +392,10 @@ if you want to write something up!). For more information about LLVM, check out:
+ src="http://jigsaw.w3.org/css-validator/images/vcss-blue" alt="Valid CSS">