Use ArtMethod* .bss entries for HInvokeStaticOrDirect.
Test: m test-art-host-gtest
Test: testrunner.py --host
Test: testrunner.py --target
Test: Nexus 6P boots.
Test: Build aosp_mips64-userdebug.
Bug: 30627598
Change-Id: I0e54fdd2e91e983d475b7a04d40815ba89ae3d4f
diff --git a/runtime/method_bss_mapping.h b/runtime/method_bss_mapping.h
new file mode 100644
index 0000000..1476f93
--- /dev/null
+++ b/runtime/method_bss_mapping.h
@@ -0,0 +1,57 @@
+/*
+ * Copyright (C) 2017 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.
+ */
+
+#ifndef ART_RUNTIME_METHOD_BSS_MAPPING_H_
+#define ART_RUNTIME_METHOD_BSS_MAPPING_H_
+
+#include "base/bit_utils.h"
+#include "base/length_prefixed_array.h"
+
+namespace art {
+
+// MethodBssMappingEntry describes a mapping of up to 17 method indexes to their offsets
+// in the .bss. The highest index and its associated .bss offset are stored in plain form
+// as `method_index` and `bss_offset`, respectively, while the additional indexes can be
+// stored in compressed form if their associated .bss entries are consecutive and in the
+// method index order. Each of the 16 bits of the `index_mask` corresponds to one of the
+// previous 16 method indexes and indicates whether there is a .bss entry for that index.
+//
+struct MethodBssMappingEntry {
+ bool CoversIndex(uint32_t method_idx) const {
+ uint32_t diff = method_index - method_idx;
+ return (diff == 0) || (diff <= 16 && ((index_mask >> (16u - diff)) & 1u) != 0);
+ }
+
+ uint32_t GetBssOffset(uint32_t method_idx, size_t entry_size) const {
+ DCHECK(CoversIndex(method_idx));
+ uint32_t diff = method_index - method_idx;
+ if (diff == 0) {
+ return bss_offset;
+ } else {
+ return bss_offset - POPCOUNT(index_mask >> (16u - diff)) * entry_size;
+ }
+ }
+
+ uint16_t method_index;
+ uint16_t index_mask;
+ uint32_t bss_offset;
+};
+
+using MethodBssMapping = LengthPrefixedArray<MethodBssMappingEntry>;
+
+} // namespace art
+
+#endif // ART_RUNTIME_METHOD_BSS_MAPPING_H_