# HG changeset patch # User kvn # Date 1213393747 25200 # Node ID 6d13fcb3663fd17a538ee63b1306497e06990ebe # Parent 3ad4bacbcdbee1e389563ad9a8f3a0602d1a4bdf 6714404: Add UseStringCache switch to enable String caching under AggressiveOpts Summary: Poke String.stringCacheEnabled during vm initialization Reviewed-by: never diff -r 3ad4bacbcdbe -r 6d13fcb3663f src/share/vm/classfile/vmSymbols.hpp --- a/src/share/vm/classfile/vmSymbols.hpp Tue Jun 10 11:14:27 2008 -0700 +++ b/src/share/vm/classfile/vmSymbols.hpp Fri Jun 13 14:49:07 2008 -0700 @@ -283,6 +283,7 @@ template(cache_field_name, "cache") \ template(value_name, "value") \ template(frontCacheEnabled_name, "frontCacheEnabled") \ + template(stringCacheEnabled_name, "stringCacheEnabled") \ \ /* non-intrinsic name/signature pairs: */ \ template(register_method_name, "register") \ diff -r 3ad4bacbcdbe -r 6d13fcb3663f src/share/vm/runtime/globals.hpp --- a/src/share/vm/runtime/globals.hpp Tue Jun 10 11:14:27 2008 -0700 +++ b/src/share/vm/runtime/globals.hpp Fri Jun 13 14:49:07 2008 -0700 @@ -2246,6 +2246,9 @@ product(bool, AggressiveOpts, false, \ "Enable aggressive optimizations - see arguments.cpp") \ \ + product(bool, UseStringCache, false, \ + "Enable String cache capabilities on String.java") \ + \ /* statistics */ \ develop(bool, UseVTune, false, \ "enable support for Intel's VTune profiler") \ diff -r 3ad4bacbcdbe -r 6d13fcb3663f src/share/vm/runtime/thread.cpp --- a/src/share/vm/runtime/thread.cpp Tue Jun 10 11:14:27 2008 -0700 +++ b/src/share/vm/runtime/thread.cpp Fri Jun 13 14:49:07 2008 -0700 @@ -2926,21 +2926,42 @@ } if (AggressiveOpts) { - // Forcibly initialize java/util/HashMap and mutate the private - // static final "frontCacheEnabled" field before we start creating instances + { + // Forcibly initialize java/util/HashMap and mutate the private + // static final "frontCacheEnabled" field before we start creating instances #ifdef ASSERT - klassOop tmp_k = SystemDictionary::find(vmSymbolHandles::java_util_HashMap(), Handle(), Handle(), CHECK_0); - assert(tmp_k == NULL, "java/util/HashMap should not be loaded yet"); + klassOop tmp_k = SystemDictionary::find(vmSymbolHandles::java_util_HashMap(), Handle(), Handle(), CHECK_0); + assert(tmp_k == NULL, "java/util/HashMap should not be loaded yet"); #endif - klassOop k_o = SystemDictionary::resolve_or_null(vmSymbolHandles::java_util_HashMap(), Handle(), Handle(), CHECK_0); - KlassHandle k = KlassHandle(THREAD, k_o); - guarantee(k.not_null(), "Must find java/util/HashMap"); - instanceKlassHandle ik = instanceKlassHandle(THREAD, k()); - ik->initialize(CHECK_0); - fieldDescriptor fd; - // Possible we might not find this field; if so, don't break - if (ik->find_local_field(vmSymbols::frontCacheEnabled_name(), vmSymbols::bool_signature(), &fd)) { - k()->bool_field_put(fd.offset(), true); + klassOop k_o = SystemDictionary::resolve_or_null(vmSymbolHandles::java_util_HashMap(), Handle(), Handle(), CHECK_0); + KlassHandle k = KlassHandle(THREAD, k_o); + guarantee(k.not_null(), "Must find java/util/HashMap"); + instanceKlassHandle ik = instanceKlassHandle(THREAD, k()); + ik->initialize(CHECK_0); + fieldDescriptor fd; + // Possible we might not find this field; if so, don't break + if (ik->find_local_field(vmSymbols::frontCacheEnabled_name(), vmSymbols::bool_signature(), &fd)) { + k()->bool_field_put(fd.offset(), true); + } + } + + if (UseStringCache) { + // Forcibly initialize java/lang/String and mutate the private + // static final "stringCacheEnabled" field before we start creating instances +#ifdef ASSERT + klassOop tmp_k = SystemDictionary::find(vmSymbolHandles::java_lang_String(), Handle(), Handle(), CHECK_0); + assert(tmp_k == NULL, "java/lang/String should not be loaded yet"); +#endif + klassOop k_o = SystemDictionary::resolve_or_null(vmSymbolHandles::java_lang_String(), Handle(), Handle(), CHECK_0); + KlassHandle k = KlassHandle(THREAD, k_o); + guarantee(k.not_null(), "Must find java/lang/String"); + instanceKlassHandle ik = instanceKlassHandle(THREAD, k()); + ik->initialize(CHECK_0); + fieldDescriptor fd; + // Possible we might not find this field; if so, don't break + if (ik->find_local_field(vmSymbols::stringCacheEnabled_name(), vmSymbols::bool_signature(), &fd)) { + k()->bool_field_put(fd.offset(), true); + } } }