-bash：opt：在MAC OS X Yosemite中找不到命令

Question

I am trying to run a LLVM pass and have the following version of gcc:

Configured with:

-- prefix=/Applications/Xcode.app/Contents/Developer/usr --with-gxx-include-dir=/usr/include/c++/4.2.1
Apple LLVM version 6.1.0 (clang-602.0.53) (based on LLVM 3.6.0svn)
Target: x86_64-apple-darwin14.5.0
Thread model: posix

I downloaded the LLVM 3.2 source from the official site and have that unzipped in my project folder.

From the project folder I am trying to run the following command:

opt -load /Users/jigs/Downloads/CS_298/llvm-3.1.src/lib/Transforms/LLVMHello.dylib -hello -S morph_1.s mul -o=morph_output.s

I get an error saying opt does not exist. I am pretty sure opt is a part of LLVM source but it does not work.

Answer 1

The opt tool should appear in the bin directory after building (yours will be version 3.xx) , so I believe you are looking in the wrong place altogether. The opt in tools is a directory, so that's certainly not going to do much for you.

/llvm-3.7.0.src/build/bin

$ ./opt -version

LLVM (http://llvm.org/):
  LLVM version 3.7.0
  DEBUG build with assertions.
  Built Sep  8 2015 (17:54:06).
  Default target: x86_64-apple-darwin14.5.0
  Host CPU: ivybridge

If you don't have a bin directory present after compiling/building from source then something likely isn't correct within your makefile perhaps.

TIP : Often you can tell where the executables are that were built by looking at the most recently modified directory within the source tree. Also, I think the easiest and most hassle free way to build LLVM from source is to use CMake — it conveniently includes a CMakeLists.txt config.