Write legacy function attributes properly.
Bug: 9503142
A prior LLVM rebase accidentally overwrote the various bitcode writer
implementations with respect to function attributes. They were writing a new
style section, which would not be able to be parsed/used on older devices.
This change restores the generation of the legacy function attribute bitcode
format.
Change-Id: Ib6afc5ae405303881605c51c34b6966e4754c29d
diff --git a/legacy_bitcode.h b/legacy_bitcode.h
new file mode 100644
index 0000000..5d45a1b
--- /dev/null
+++ b/legacy_bitcode.h
@@ -0,0 +1,32 @@
+/*
+ * Copyright 2013, 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 "llvm/IR/Attributes.h"
+
+// Shared functionality for legacy function attribute encoding.
+static inline uint64_t encodeLLVMAttributesForBitcode(llvm::AttributeSet A,
+ unsigned i) {
+ uint64_t EncodedAttrs = A.Raw(i) & 0xffff;
+ if (A.hasAttribute(i, llvm::Attribute::Alignment)) {
+ // The alignment is stored as an actual power of 2 value (instead of the
+ // compressed log2 form). It occupies bits 31-16 inclusive.
+ EncodedAttrs |= (A.getParamAlignment(i) << 16);
+ }
+ // There are only 12 remaining attributes (bits 21-32), hence our 0xfff mask.
+ EncodedAttrs |= (A.Raw(i) & (0xfffull << 21)) << 11;
+ return EncodedAttrs;
+}
+