fix possible NPE in TruffleCompiler with TraceTruffleCompilation and background compilation enabled. With background compilation, the installed code can already be invalidated when compiledMethod.getCode() is called, in which case it returns null.

os_family = bsd

arch = sparc

arch_model = sparc

os_arch = bsd_sparc

os_arch_model = bsd_sparc

lib_arch = sparc

compiler = gcc

sysdefs = -D_ALLBSD_SOURCE -D_GNU_SOURCE -DSPARC