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+// Obtained from https://github.com/llvm/llvm-project/blob/main/llvm/lib/Support/SmallVector.cpp
+// commit 4b82bb6d82f65f98f23d0e4c2cd5297dc162864c
+// adapted in code style and utilities to fix this project
+
+//===- llvm/ADT/SmallVector.cpp - 'Normally small' vectors ----------------===//
+//
+// 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 implements the SmallVector class.
+//
+//===----------------------------------------------------------------------===//
+
+#include "SmallVector.hpp"
+
+#include <cstdlib>
+#include <stdexcept>
+#include <string>
+
+// Check that no bytes are wasted and everything is well-aligned.
+namespace {
+// These structures may cause binary compat warnings on AIX. Suppress the
+// warning since we are only using these types for the static assertions below.
+#if defined(_AIX)
+# pragma GCC diagnostic push
+# pragma GCC diagnostic ignored "-Waix-compat"
+#endif
+struct Struct16B {
+ alignas(16) void* X;
+};
+struct Struct32B {
+ alignas(32) void* X;
+};
+#if defined(_AIX)
+# pragma GCC diagnostic pop
+#endif
+} // namespace
+static_assert(sizeof(SmallVector<void*, 0>) ==
+ sizeof(unsigned) * 2 + sizeof(void*),
+ "wasted space in SmallVector size 0");
+static_assert(alignof(SmallVector<Struct16B, 0>) >= alignof(Struct16B),
+ "wrong alignment for 16-byte aligned T");
+static_assert(alignof(SmallVector<Struct32B, 0>) >= alignof(Struct32B),
+ "wrong alignment for 32-byte aligned T");
+static_assert(sizeof(SmallVector<Struct16B, 0>) >= alignof(Struct16B),
+ "missing padding for 16-byte aligned T");
+static_assert(sizeof(SmallVector<Struct32B, 0>) >= alignof(Struct32B),
+ "missing padding for 32-byte aligned T");
+static_assert(sizeof(SmallVector<void*, 1>) ==
+ sizeof(unsigned) * 2 + sizeof(void*) * 2,
+ "wasted space in SmallVector size 1");
+
+static_assert(sizeof(SmallVector<char, 0>) ==
+ sizeof(void*) * 2 + sizeof(void*),
+ "1 byte elements have word-sized type for size and capacity");
+
+/// Report that MinSize doesn't fit into this vector's size type. Throws
+/// std::length_error or calls report_fatal_error.
+[[noreturn]] static void report_size_overflow(size_t MinSize, size_t MaxSize);
+static void report_size_overflow(size_t MinSize, size_t MaxSize) {
+ std::string Reason = "SmallVector unable to grow. Requested capacity (" +
+ std::to_string(MinSize) +
+ ") is larger than maximum value for size type (" +
+ std::to_string(MaxSize) + ")";
+ throw std::length_error(Reason);
+}
+
+/// Report that this vector is already at maximum capacity. Throws
+/// std::length_error or calls report_fatal_error.
+[[noreturn]] static void report_at_maximum_capacity(size_t MaxSize);
+static void report_at_maximum_capacity(size_t MaxSize) {
+ std::string Reason =
+ "SmallVector capacity unable to grow. Already at maximum size " +
+ std::to_string(MaxSize);
+ throw std::length_error(Reason);
+}
+
+// Note: Moving this function into the header may cause performance regression.
+template <class Size_T>
+static size_t getNewCapacity(size_t MinSize, size_t TSize, size_t OldCapacity) {
+ constexpr size_t MaxSize = std::numeric_limits<Size_T>::max();
+
+ // Ensure we can fit the new capacity.
+ // This is only going to be applicable when the capacity is 32 bit.
+ if (MinSize > MaxSize)
+ report_size_overflow(MinSize, MaxSize);
+
+ // Ensure we can meet the guarantee of space for at least one more element.
+ // The above check alone will not catch the case where grow is called with a
+ // default MinSize of 0, but the current capacity cannot be increased.
+ // This is only going to be applicable when the capacity is 32 bit.
+ if (OldCapacity == MaxSize)
+ report_at_maximum_capacity(MaxSize);
+
+ // In theory 2*capacity can overflow if the capacity is 64 bit, but the
+ // original capacity would never be large enough for this to be a problem.
+ size_t NewCapacity = 2 * OldCapacity + 1; // Always grow.
+ return std::min(std::max(NewCapacity, MinSize), MaxSize);
+}
+
+// Note: Moving this function into the header may cause performance regression.
+template <class Size_T>
+void* SmallVectorBase<Size_T>::mallocForGrow(size_t MinSize, size_t TSize, size_t& NewCapacity) {
+ NewCapacity = getNewCapacity<Size_T>(MinSize, TSize, this->capacity());
+ return malloc(NewCapacity * TSize);
+}
+
+// Note: Moving this function into the header may cause performance regression.
+template <class Size_T>
+void SmallVectorBase<Size_T>::grow_pod(void* FirstEl, size_t MinSize, size_t TSize) {
+ size_t NewCapacity = getNewCapacity<Size_T>(MinSize, TSize, this->capacity());
+ void* NewElts;
+ if (BeginX == FirstEl) {
+ NewElts = malloc(NewCapacity * TSize);
+
+ // Copy the elements over. No need to run dtors on PODs.
+ memcpy(NewElts, this->BeginX, size() * TSize);
+ } else {
+ // If this wasn't grown from the inline copy, grow the allocated space.
+ NewElts = realloc(this->BeginX, NewCapacity * TSize);
+ }
+
+ this->BeginX = NewElts;
+ this->Capacity = NewCapacity;
+}
+
+template class SmallVectorBase<uint32_t>;
+
+// Disable the uint64_t instantiation for 32-bit builds.
+// Both uint32_t and uint64_t instantiations are needed for 64-bit builds.
+// This instantiation will never be used in 32-bit builds, and will cause
+// warnings when sizeof(Size_T) > sizeof(size_t).
+#if SIZE_MAX > UINT32_MAX
+template class SmallVectorBase<uint64_t>;
+
+// Assertions to ensure this #if stays in sync with SmallVectorSizeType.
+static_assert(sizeof(SmallVectorSizeType<char>) == sizeof(uint64_t),
+ "Expected SmallVectorBase<uint64_t> variant to be in use.");
+#else
+static_assert(sizeof(SmallVectorSizeType<char>) == sizeof(uint32_t),
+ "Expected SmallVectorBase<uint32_t> variant to be in use.");
+#endif