Ensure instruction cache is flushed in compiler tests with Clang.
Invoke __builtin___clear_cache with Clang in
art::CommonCompilerTest::MakeExecutable. This fixes
"Illegal instruction" failures in codegen_test on angler.
Factor this logic in a function and use it in
art::jit::JitCodeCache::CommitCodeInternal too.
Bug: 26786447
Change-Id: I81fa056c8d7c6bf2168c9340deeab82231cb1084
diff --git a/runtime/utils.h b/runtime/utils.h
index 153749e..c00db11 100644
--- a/runtime/utils.h
+++ b/runtime/utils.h
@@ -388,6 +388,24 @@
// Sleep forever and never come back.
NO_RETURN void SleepForever();
+inline void FlushInstructionCache(char* begin, char* end) {
+ // Only use __builtin___clear_cache with Clang or with GCC >= 4.3.0
+ // (__builtin___clear_cache was introduced in GCC 4.3.0).
+#if defined(__clang__) || GCC_VERSION >= 40300
+ __builtin___clear_cache(begin, end);
+#else
+ // Only warn on non-Intel platforms, as x86 and x86-64 do not need
+ // cache flush instructions, as long as the "code uses the same
+ // linear address for modifying and fetching the instruction". See
+ // "Intel(R) 64 and IA-32 Architectures Software Developer's Manual
+ // Volume 3A: System Programming Guide, Part 1", section 11.6
+ // "Self-Modifying Code".
+#if !defined(__i386__) && !defined(__x86_64__)
+ UNIMPLEMENTED(WARNING) << "cache flush";
+#endif
+#endif
+}
+
} // namespace art
#endif // ART_RUNTIME_UTILS_H_