This guide is meant to get you up and running with LLVM as quickly as - possible. Once you get the basic system running you can choose an area to - dive into and learn more about. If you get stuck or something is missing - from this document, please email Chris.
- +The next section of this guide is meant to get + you up and running with LLVM, and to give you some basic information about + the LLVM environment. The first subsection gives + a short summary for those who are already familiar with the system and + want to get started as quickly as possible. + +
The later sections of this guide describe the general layout of the the llvm source tree, a simple example using the LLVM tool chain, and links to find more information about LLVM or to get + help via e-mail. + + +
See Setting up your environment on tips to + simplify working with the llvm front-end and compiled tools. See the + other sub-sections below for other useful details in working with LLVM, + or go straight to Program Layout to learn about the + layout of the source code tree. -
First step is to get the actual source code. To do this, all you need to - do is check it out from CVS. From your home directory, just enter:
- -cvs -d /home/vadve/vadve/Research/DynOpt/CVSRepository checkout - llvm
- -This will create an 'llvm' directory in your home directory and - fully populate it with the source code for LLVM.
- +Through this manual, the following names are used to denote paths + specific to the local system and working environment. These are not + environment variables you need to set, but just strings used in the rest + of this document below.. In any of the examples below, simply replace + each of these names with the appropriate pathname on your local system. + All these paths are absolute:
+- - The first modification is that you need to enable the "BUILD_ROOT = - . line in the top level Makefile.common. This will instruct - LLVM to build into the current directory tree instead of - /shared.
+
Before checking out the source code, you will need to know the path to + CVS repository containing LLVM source code (we'll call this + CVSROOTDIR below). Ask the person responsible for your local LLVM + installation to give you this path. +
To get a fresh copy of the entire source code, 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.
-Now that you have the source code available, you should set up your - environment to be able to use the LLVM tools (once compiled) with as little - hassle as possible. To do this, we recommend that you add the following - lines to your .cshrc (or the corresponding lines to your - .profile if you use a bourne shell derivative): + +
The file llvm/Makefile.config + defines the following path variables, + which are specific to a particular installation of LLVM. + These should need to be modified only once after checking out a copy + of LLVM (if the default values do not already match your system): + +
The LLVM make system sends most output files generated during the build + into the directory defined by the variable LLVM_OBJ_DIR in + llvm/Makefile.config. + This can be either just your normal llvm source tree or some + other directory writable by you. You may wish to put object files on a + different filesystem either to keep them from being backed up or to speed + up local builds. + +
If you do not wish to use a different location for object files, + just set this variable to ".". + + +
Add the following lines to your .cshrc (or the corresponding + lines to your .profile if you use a bourne shell derivative).
- # Make the C frontend easy to use...
- alias llvmgcc /home/vadve/lattner/cvs/gcc_install/bin/gcc
+ # Make the C front end easy to use...
+ alias llvmgcc LLVMGCCDIR/bin/gcc
# Make the LLVM tools easy to use...
- setenv PATH /shared/[yourloginname]/llvm/tools/Debug:${PATH}
+ setenv PATH LLVM_OBJ_DIR/tools/Debug:${PATH}
-
- The C compiler is not included in the CVS tree you just checked out, so - we just point to the cannonical location, and access it with the - llvmgcc command. The rest of the LLVM tools - will be built into the llvm/tools/Debug directory. If you do not - have access to /shared, use this line instead:
- -
- setenv PATH ~/llvm/tools/Debug:${PATH}
-
-
- Adding these two lines to your path will make it much easier to use the LLVM
- tools.
-
+ The llvmgcc alias is useful because the C compiler is not
+ included in the CVS tree you just checked out.
+
+ The other LLVM LLVM tools are part of the LLVM + source base, and built when compiling LLVM. They will be built into the + LLVM_OBJ_DIR/tools/Debug directory.
-Every directory in the LLVM source tree includes a Makefile to build it, @@ -121,17 +196,16 @@ in llvm/tools/Debug. If you want to look at the libraries that were compiled, look in llvm/lib/Debug.
-By default, the LLVM build process sends all temporary (.o, - .so, .a) files into a /shared/[your login - name]/... directory, which is supposed to be on a disk local to the - current machine. If you get an error talking about a /shared - directory, follow the instructions in the section about - /shared.
+ If you get an error talking about a /shared directory, follow the + instructions in the section about Setting Up Your + Environment. -
One useful source of infomation about the LLVM sourcebase is the LLVM
+ additions...), please send an email to
+ Nicholas Hildenbrandt or
+ Chris Lattner.
-
If you have any questions or run into any snags (or you have any
- additions...), please send an email to Chris Lattner or Guochun Shi.