This patch adds a new class, OrcI386, which contains the hooks needed to
support lazy-JITing on i386 (currently only for Pentium 2 or above, as the JIT
re-entry code uses the FXSAVE/FXRSTOR instructions).
Support for i386 is enabled in the LLI lazy JIT and the Orc C API, and
regression and unit tests are enabled for this architecture.
llvm-svn: 260338