diff options
Diffstat (limited to 'runtime')
-rw-r--r-- | runtime/stack_indirect_reference_table.h | 18 | ||||
-rw-r--r-- | runtime/stack_indirect_reference_table_test.cc | 58 |
2 files changed, 69 insertions, 7 deletions
diff --git a/runtime/stack_indirect_reference_table.h b/runtime/stack_indirect_reference_table.h index 6049e06..b113129 100644 --- a/runtime/stack_indirect_reference_table.h +++ b/runtime/stack_indirect_reference_table.h @@ -44,6 +44,10 @@ class StackIndirectReferenceTable { return number_of_references_; } + // We have versions with and without explicit pointer size of the following. The first two are + // used at runtime, so OFFSETOF_MEMBER computes the right offsets automatically. The last one + // takes the pointer size explicitly so that at compile time we can cross-compile correctly. + // Returns the size of a StackIndirectReferenceTable containing num_references sirts. static size_t SizeOf(uint32_t num_references) { size_t header_size = OFFSETOF_MEMBER(StackIndirectReferenceTable, references_); @@ -60,7 +64,7 @@ class StackIndirectReferenceTable { // Get the size of the SIRT for the number of entries, with padding added for potential alignment. static size_t GetAlignedSirtSizeTarget(size_t pointer_size, uint32_t num_references) { // Assume that the layout is packed. - size_t header_size = pointer_size + sizeof(uint32_t); + size_t header_size = pointer_size + sizeof(number_of_references_); // This assumes there is no layout change between 32 and 64b. size_t data_size = sizeof(StackReference<mirror::Object>) * num_references; size_t sirt_size = header_size + data_size; @@ -109,18 +113,18 @@ class StackIndirectReferenceTable { } // Offset of link within SIRT, used by generated code - static size_t LinkOffset() { - return OFFSETOF_MEMBER(StackIndirectReferenceTable, link_); + static size_t LinkOffset(size_t pointer_size) { + return 0; } // Offset of length within SIRT, used by generated code - static uint32_t NumberOfReferencesOffset() { - return OFFSETOF_MEMBER(StackIndirectReferenceTable, number_of_references_); + static size_t NumberOfReferencesOffset(size_t pointer_size) { + return pointer_size; } // Offset of link within SIRT, used by generated code - static size_t ReferencesOffset() { - return OFFSETOF_MEMBER(StackIndirectReferenceTable, references_); + static size_t ReferencesOffset(size_t pointer_size) { + return pointer_size + sizeof(number_of_references_); } private: diff --git a/runtime/stack_indirect_reference_table_test.cc b/runtime/stack_indirect_reference_table_test.cc new file mode 100644 index 0000000..72ef6b6 --- /dev/null +++ b/runtime/stack_indirect_reference_table_test.cc @@ -0,0 +1,58 @@ +/* + * Copyright (C) 2014 The Android Open Source Project + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#include "stack_indirect_reference_table.h" +#include "gtest/gtest.h" + +namespace art { + +// Test the offsets computed for members of StackIndirectReferenceTable. Because of cross-compiling +// it is impossible the use OFFSETOF_MEMBER, so we do some reasonable computations ourselves. This +// test checks whether we do the right thing. +TEST(StackIndirectReferenceTableTest, Offsets) { + // As the members of StackIndirectReferenceTable are private, we cannot use OFFSETOF_MEMBER + // here. So do the inverse: set some data, and access it through pointers created from the offsets. + + StackIndirectReferenceTable test_table(reinterpret_cast<mirror::Object*>(0x1234)); + test_table.SetLink(reinterpret_cast<StackIndirectReferenceTable*>(0x5678)); + test_table.SetNumberOfReferences(0x9ABC); + + byte* table_base_ptr = reinterpret_cast<byte*>(&test_table); + + { + uintptr_t* link_ptr = reinterpret_cast<uintptr_t*>(table_base_ptr + + StackIndirectReferenceTable::LinkOffset(kPointerSize)); + EXPECT_EQ(*link_ptr, static_cast<size_t>(0x5678)); + } + + { + uint32_t* num_ptr = reinterpret_cast<uint32_t*>(table_base_ptr + + StackIndirectReferenceTable::NumberOfReferencesOffset(kPointerSize)); + EXPECT_EQ(*num_ptr, static_cast<size_t>(0x9ABC)); + } + + { + // Assume sizeof(StackReference<mirror::Object>) == sizeof(uint32_t) + // TODO: How can we make this assumption-less but still access directly and fully? + EXPECT_EQ(sizeof(StackReference<mirror::Object>), sizeof(uint32_t)); + + uint32_t* ref_ptr = reinterpret_cast<uint32_t*>(table_base_ptr + + StackIndirectReferenceTable::ReferencesOffset(kPointerSize)); + EXPECT_EQ(*ref_ptr, static_cast<uint32_t>(0x1234)); + } +} + +} // namespace art |