src/share/vm/oops/arrayOop.cpp

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rev 2779 : 7102044: G1: VM crashes with assert(old_end != new_end) failed: don't call this otherwise
Summary: arrayOopDesc::max_array_length() should return a value that does not overflow a size_t if it is converted to bytes.
Reviewed-by: duke

*** 22,31 **** * */ #include "precompiled.hpp" #include "oops/arrayOop.hpp" - #include "oops/objArrayOop.hpp" - #include "oops/oop.inline.hpp" - #include "oops/symbol.hpp" ! // <<this page is intentionally left blank>> --- 22,88 ---- * */ #include "precompiled.hpp" #include "oops/arrayOop.hpp" ! #ifndef PRODUCT ! ! #include "utilities/globalDefinitions.hpp" ! // Unit tests ! ! bool arrayOopDesc::check_overflow(BasicType type) { ! int32_t length = max_array_length(type); ! size_t bytes_per_element = type2aelembytes(type); ! size_t bytes = (size_t)length * bytes_per_element + header_size_in_bytes(); ! return (bytes - header_size_in_bytes()) / bytes_per_element == (size_t)length; ! } ! ! // The old implementation of max_array_length. For 64-bit platforms the old ! // and new implementations should return the same value. ! int32_t arrayOopDesc::old_max_array_length(BasicType type) { ! const int bytes_per_element = type2aelembytes(type); ! if (bytes_per_element < HeapWordSize) { ! return max_jint; ! } ! const int32_t max_words = align_size_down(max_jint, MinObjAlignment); ! const int32_t max_element_words = max_words - header_size(type); ! const int32_t words_per_element = bytes_per_element >> LogHeapWordSize; ! return max_element_words / words_per_element; ! } ! ! bool arrayOopDesc::test_max_array_length() { ! tty->print_cr("test_max_array_length"); ! ! assert(check_overflow(T_BOOLEAN), "size_t overflow for boolean array"); ! assert(check_overflow(T_CHAR), "size_t overflow for char array"); ! assert(check_overflow(T_FLOAT), "size_t overflow for float array"); ! assert(check_overflow(T_DOUBLE), "size_t overflow for double array"); ! assert(check_overflow(T_BYTE), "size_t overflow for byte array"); ! assert(check_overflow(T_SHORT), "size_t overflow for short array"); ! assert(check_overflow(T_INT), "size_t overflow for int array"); ! assert(check_overflow(T_LONG), "size_t overflow for long array"); ! assert(check_overflow(T_OBJECT), "size_t overflow for object array"); ! assert(check_overflow(T_ARRAY), "size_t overflow for array array"); ! assert(check_overflow(T_NARROWOOP), "size_t overflow for narrowOop array"); ! ! // T_VOID and T_ADDRESS are not supported by max_array_length() ! ! #ifdef _LP64 ! assert(max_array_length(T_BOOLEAN) == old_max_array_length(T_BOOLEAN), "calculation changed for boolean"); ! assert(max_array_length(T_CHAR) == old_max_array_length(T_CHAR), "calculation changed for char"); ! assert(max_array_length(T_FLOAT) == old_max_array_length(T_FLOAT), "calculation changed for float"); ! assert(max_array_length(T_DOUBLE) == old_max_array_length(T_DOUBLE), "calculation changed for double"); ! assert(max_array_length(T_BYTE) == old_max_array_length(T_BYTE), "calculation changed for byte"); ! assert(max_array_length(T_SHORT) == old_max_array_length(T_SHORT), "calculation changed for short"); ! assert(max_array_length(T_INT) == old_max_array_length(T_INT), "calculation changed for int"); ! assert(max_array_length(T_LONG) == old_max_array_length(T_LONG), "calculation changed for long"); ! assert(max_array_length(T_OBJECT) == old_max_array_length(T_OBJECT), "calculation changed for object"); ! assert(max_array_length(T_ARRAY) == old_max_array_length(T_ARRAY), "calculation changed for array"); ! assert(max_array_length(T_NARROWOOP) == old_max_array_length(T_NARROWOOP), "calculation changed for narrowOop"); ! #endif ! ! return true; ! } ! ! ! #endif //PRODUCT