diff options
| -rw-r--r-- | libjava/ChangeLog | 5 | ||||
| -rw-r--r-- | libjava/boehm.cc | 46 |
2 files changed, 47 insertions, 4 deletions
diff --git a/libjava/ChangeLog b/libjava/ChangeLog index cad0018014f..cf97e58d824 100644 --- a/libjava/ChangeLog +++ b/libjava/ChangeLog @@ -1,5 +1,10 @@ 2003-07-22 Tom Tromey <tromey@redhat.com> + * boehm.cc (_Jv_BuildGCDescr): Wrote. + Include limits.h. + +2003-07-22 Tom Tromey <tromey@redhat.com> + * java/awt/Window.java (getWarningString): Just return the string. (Window): Set warningString; check with security manager. diff --git a/libjava/boehm.cc b/libjava/boehm.cc index 5006059dabd..8e621594bf2 100644 --- a/libjava/boehm.cc +++ b/libjava/boehm.cc @@ -1,6 +1,6 @@ // boehm.cc - interface between libjava and Boehm GC. -/* Copyright (C) 1998, 1999, 2000, 2001, 2002 Free Software Foundation +/* Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003 Free Software Foundation This file is part of libgcj. @@ -11,6 +11,7 @@ details. */ #include <config.h> #include <stdio.h> +#include <limits.h> #include <jvm.h> #include <gcj/cni.h> @@ -325,11 +326,48 @@ _Jv_MarkArray (void *addr, void *msp, void *msl, void * /*env*/) // since another one could be registered first. But the compiler also // knows this, so in that case everything else will break, too. #define GCJ_DEFAULT_DESCR GC_MAKE_PROC(GC_GCJ_RESERVED_MARK_PROC_INDEX,0) + void * -_Jv_BuildGCDescr(jclass) +_Jv_BuildGCDescr(jclass self) { - /* FIXME: We should really look at the class and build the descriptor. */ - return (void *)(GCJ_DEFAULT_DESCR); + jlong desc = 0; + + // Note: for now we only consider a bitmap mark descriptor. We + // could also handle the case where the first N fields of a type are + // references. However, this is not very likely to be used by many + // classes, and it is easier to compute things this way. + + for (jclass klass = self; klass != NULL; klass = klass->getSuperclass()) + { + jfieldID field = JvGetFirstInstanceField(klass); + int count = JvNumInstanceFields(klass); + + for (int i = 0; i < count; ++i) + { + if (field->isRef()) + { + unsigned int off = field->getOffset(); + // If we run into a weird situation, we bail. + if (off % sizeof (void *) != 0) + return (void *) (GCJ_DEFAULT_DESCR); + off /= sizeof (void *); + // Bottom 2 bits are reserved. + off += 2; + // If we find a field outside the range of our bitmap, + // fall back to procedure marker. + if (off > CHAR_BIT * sizeof (void *)) + return (void *) (GCJ_DEFAULT_DESCR); + desc |= 1 << off; + } + + field = field->getNextField(); + } + } + + // For bitmap mark type, bottom bits are 01. + desc |= 1; + // Bogus warning avoidance (on many platforms). + return (void *) (unsigned long) desc; } // Allocate some space that is known to be pointer-free. |