Quick compiler: restore optimizations
This CL re-enables optizations on the Quick compile path.
Notes:
o Although all optimization are enabled, several are now useless
because of llvm and bitcode constraints:
- Large method de-optimization (i.e. - skipping expensive dataflow
analysis) can't be done because we have to do the analysis to
produce a CFG that makes the bitcode verifier happy.
- Small method pattern matching isn't applicable w/ bitcode (though
I can probably do something similar in the Quick backend, but
looking for bitcode instead of dex patterns).
- Branch fusing doesn't translate to bitcode.
- Bitcode generation has de-optimized code layout. We'll try to
repair the damage in a subsequent CL.
o There is an ugly workaround related to the way we're loading and
unloading the compiler .so containing llvm. [See comment in compiler.cc]
o We're still running single-threaded - need to add the magic to allow
multi-threaded use of llvm.
o With the CL, the phone boots, all target tests pass and all cts VM
tests pass (except those being dealt with via a verifier change).
o Compile time is pretty bad - when flashing it's best to follow
with an adb sync to avoid on-device compilation of system apps.
Change-Id: I1c98f9e64aefbcbd24b957c71544c28450eb2023
diff --git a/src/compiler.cc b/src/compiler.cc
index b06f718..e31b9b5 100644
--- a/src/compiler.cc
+++ b/src/compiler.cc
@@ -390,7 +390,20 @@
#endif
if (compiler_library_ != NULL) {
VLOG(compiler) << "dlclose(" << compiler_library_ << ")";
+#if !defined(ART_USE_QUICK_COMPILER)
+ /*
+ * FIXME: Temporary workaround
+ * Apparently, llvm is adding dctors to atexit, but if we unload
+ * the library here the code will no longer be around at exit time
+ * and we die a flaming death in __cxa_finalize(). Apparently, some
+ * dlclose() implementations will scan the atexit list on unload and
+ * handle any associated with the soon-to-be-unloaded library.
+ * However, this is not required by POSIX and we don't do it.
+ * See: http://b/issue?id=4998315
+ * What's the right thing to do here?
+ */
dlclose(compiler_library_);
+#endif
}
}