[compiler-rt] [scudo] Refactor allocator config to support optional flags (PR #81805)

[via llvm-commits]

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@@ -0,0 +1,123 @@
+//===-- allocator_config.def ------------------------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines all the flags and types supported in Scudo.
+
+#ifndef BASE_REQUIRED_TEMPLATE_TYPE
+#define BASE_REQUIRED_TEMPLATE_TYPE(...)
+#endif
+#ifndef BASE_OPTIONAL
+#define BASE_OPTIONAL(...)
+#endif
+#ifndef PRIMARY_REQUIRED_TYPE
+#define PRIMARY_REQUIRED_TYPE(...)
+#endif
+#ifndef PRIMARY_REQUIRED
+#define PRIMARY_REQUIRED(...)
+#endif
+#ifndef PRIMARY_OPTIONAL
+#define PRIMARY_OPTIONAL(...)
+#endif
+#ifndef PRIMARY_OPTIONAL_TYPE
+#define PRIMARY_OPTIONAL_TYPE(...)
+#endif
+#ifndef SECONDARY_REQUIRED_TEMPLATE_TYPE
+#define SECONDARY_REQUIRED_TEMPLATE_TYPE(...)
+#endif
+#ifndef SECONDARY_CACHE_OPTIONAL
+#define SECONDARY_CACHE_OPTIONAL(...)
+#endif
+
+// BASE_REQUIRED_TEMPLATE_TYPE(NAME)
+//
+// Thread-Specific Data Registry used, shared or exclusive.
+BASE_REQUIRED_TEMPLATE_TYPE(TSDRegistryT)
+
+// Defines the type of Primary allocator to use.
+BASE_REQUIRED_TEMPLATE_TYPE(PrimaryT)
+
+// Defines the type of Secondary allocator to use.
+BASE_REQUIRED_TEMPLATE_TYPE(SecondaryT)
+
+// BASE_OPTIONAL(TYPE, NAME, DEFAULT)
+//
+// Indicates possible support for Memory Tagging.
+BASE_OPTIONAL(const bool, MaySupportMemoryTagging, false)
+
+// PRIMARY_REQUIRED_TYPE(NAME)
+//
+// SizeClassMap to use with the Primary.
+PRIMARY_REQUIRED_TYPE(SizeClassMap)
+
+// Defines the type and scale of a compact pointer. A compact pointer can
+// be understood as the offset of a pointer within the region it belongs
+// to, in increments of a power-of-2 scale. See `CompactPtrScale` also.
+PRIMARY_REQUIRED_TYPE(CompactPtrT)
+
+// PRIMARY_REQUIRED(TYPE, NAME)
+//
+// The scale of a compact pointer. E.g., Ptr = Base + (CompactPtr << Scale).
+PRIMARY_REQUIRED(const uptr, CompactPtrScale)
+
+// Log2 of the size of a size class region, as used by the Primary.
+PRIMARY_REQUIRED(const uptr, RegionSizeLog)
+
+// Log2 of the size of block group, as used by the Primary. Each group
+// contains a range of memory addresses, blocks in the range will belong
+// to the same group. In general, single region may have 1 or 2MB group
+// size. Multiple regions will have the group size equal to the region
+// size because the region size is usually smaller than 1 MB.
+// Smaller value gives fine-grained control of memory usage but the
+// trade-off is that it may take longer time of deallocation.
----------------
ChiaHungDuan wrote:

You're right. I revised the comment here. Let me know if it's more clear

https://github.com/llvm/llvm-project/pull/81805