llgo is a Go frontend for LLVM, written in Go.
llgo is under active development, but is still considered experimental. It is not presently useful for real work. Progress will be reported at http://blog.awilkins.id.au.
To install llgo, use llgo-dist:
go get github.com/axw/llgo/cmd/llgo-dist
llgo-dist
You should have the latest version of LLVM in your $PATH (3.3 has been confirmed to be compatible). If LLVM is not in $PATH, llgo-dist also has a flag that can specified to point at the LLVM installation: -llvm-config=<path/to/llvm-config>.
llgo requires Go 1.2+.
llgo-dist builds two binaries: there's llgo, the compiler; and there's llgo-build, which is a poor man's go build for llgo.
The compiler is comparable with 6g: it takes a set of Go source files as arguments, and produces an object file. The output is an LLVM bitcode module. There are several flags that alter the behaviour: -triple=<triple> specifies the target LLVM triple to compile for; -dump causes llgo to dump the module in its textual IR form instead of generating bitcode.
The llgo-build tool accepts either Go filenames, or package names, just like go build. If the package is a command, then llgo-build will compile it, link in its dependencies, and translate the LLVM bitcode to a native binary. If you want an untranslated module, specify the -emit-llvm flag.
llgo-build has some additional flags for testing: -run causes llgo-build to execute and dispose of the resultant binary. Passing -test causes llgo-build to generate a test program for the specified package, just like go test -c.
First install llgo using llgo-dist, as described above. Then you can run the functional tests like so:
go test -v github.com/axw/llgo/llgo
You can also run the compiler tests from gc's source tree ($GOROOT/test) by specifying the build tag go_test:
go test -v -tags go_test github.com/axw/llgo/llgo -run StandardTests