[llvm] [SYCL][LLVM] Adding property set I/O library for SYCL (PR #110771)

[Chris B via llvm-commits]

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@@ -0,0 +1,268 @@
+//=- SYCLPropertySetIO.h -- models a sequence of property sets and their I/O =//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+// Models a sequence of property sets and their input and output operations.
+// SYCLPropertyValue set format:
+//   '['<SYCLPropertyValue set name>']'
+//   <property name>=<property type>'|'<property value>
+//   <property name>=<property type>'|'<property value>
+//   ...
+//   '['<SYCLPropertyValue set name>']'
+//   <property name>=<property type>'|'<property value>
+// where
+//   <SYCLPropertyValue set name>, <property name> are strings
+//   <property type> - string representation of the property type
+//   <property value> - string representation of the property value.
+//
+// For example:
+// [Staff/Ages]
+// person1=1|20
+// person2=1|25
+// [Staff/Experience]
+// person1=1|1
+// person2=1|2
+// person3=1|12
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_SUPPORT_SYCLPROPERTYSETIO_H
+#define LLVM_SUPPORT_SYCLPROPERTYSETIO_H
+
+#include "llvm/ADT/MapVector.h"
+#include "llvm/ADT/SmallString.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/Support/Error.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm/Support/xxhash.h"
+#include <variant>
+
+namespace llvm {
+namespace util {
+
+// Represents a SYCL property value. SYCLPropertyValue name is stored in the
+// encompassing container.
+class SYCLPropertyValue {
+public:
+  // Type of the size of the value. Value size gets serialized along with the
+  // value data in some cases for later reading at runtime, so size_t is not
+  // suitable as its size varies.
+  using SizeTy = uint64_t;
+
+  // Defines supported property types
+  enum Type { first = 0, NONE = first, UINT32, BYTE_ARRAY, last = BYTE_ARRAY };
+
+  // Translates C++ type to the corresponding type tag.
+  template <typename T> static Type getTypeTag();
+
+  // Casts from int value to a type tag.
+  static Expected<Type> getTypeTag(int T) {
+    if (T < first || T > last)
+      return createStringError(std::error_code(), "bad property type ", T);
+    return static_cast<Type>(T);
+  }
+
+  ~SYCLPropertyValue() {}
+
+  SYCLPropertyValue() = default;
+  SYCLPropertyValue(Type T) : Ty(T) {}
+
+  SYCLPropertyValue(uint32_t Val) : Ty(UINT32), Val({Val}) {}
+  SYCLPropertyValue(const std::byte *Data, SizeTy DataBitSize);
+  template <typename C, typename T = typename C::value_type>
+  SYCLPropertyValue(const C &Data)
+      : SYCLPropertyValue(reinterpret_cast<const std::byte *>(Data.data()),
+                          Data.size() * sizeof(T) * CHAR_BIT) {}
+  SYCLPropertyValue(const llvm::StringRef &Str)
+      : SYCLPropertyValue(reinterpret_cast<const std::byte *>(Str.data()),
+                          Str.size() * sizeof(char) *
+                              /* bits in one byte */ 8) {}
+  SYCLPropertyValue(const SYCLPropertyValue &P);
+  SYCLPropertyValue(SYCLPropertyValue &&P);
+
+  SYCLPropertyValue &operator=(SYCLPropertyValue &&P);
+
+  SYCLPropertyValue &operator=(const SYCLPropertyValue &P);
+
+  // Get property value as unsigned 32-bit integer
+  uint32_t asUint32() const {
+    assert((Ty == UINT32) && "must be UINT32 value");
+    return std::get<uint32_t>(Val);
+  }
+
+  // Get raw data size in bits.
+  SizeTy getByteArraySizeInBits() const {
+    assert((Ty == BYTE_ARRAY) && "must be BYTE_ARRAY value");
+    SizeTy Res = 0;
+
+    for (size_t I = 0; I < sizeof(SizeTy); ++I) {
+      auto ByteArrayVal = std::get<std::byte *>(Val);
+      Res |= (SizeTy)ByteArrayVal[I] << (8 * I);
+    }
+    return Res;
+  }
+
+  // Get byte array data size in bytes.
+  SizeTy getByteArraySize() const {
+    SizeTy SizeInBits = getByteArraySizeInBits();
+    constexpr unsigned int MASK = 0x7;
+    return ((SizeInBits + MASK) & ~MASK) / 8;
+  }
+
+  // Get byte array data size in bytes, including the leading bytes encoding the
+  // size.
+  SizeTy getRawByteArraySize() const {
+    return getByteArraySize() + sizeof(SizeTy);
+  }
+
+  // Get byte array data including the leading bytes encoding the size.
+  const std::byte *asRawByteArray() const {
+    assert((Ty == BYTE_ARRAY) && "must be BYTE_ARRAY value");
+    auto *ByteArrayVal = std::get<std::byte *>(Val);
+    return ByteArrayVal;
+  }
+
+  // Get byte array data excluding the leading bytes encoding the size.
+  const std::byte *asByteArray() const {
+    assert((Ty == BYTE_ARRAY) && "must be BYTE_ARRAY value");
+
+    auto ByteArrayVal = std::get<std::byte *>(Val);
+    return ByteArrayVal + sizeof(SizeTy);
+  }
+
+  bool isValid() const { return getType() != NONE; }
+
+  // Set property value when data type is UINT32_T
+  void set(uint32_t V) {
+    assert((Ty == UINT32) && "must be UINT32 value");
+    Val = V;
+  }
+
+  // Set property value when data type is BYTE_ARRAY
+  void set(std::byte *V, int DataSize) {
+    assert((Ty == BYTE_ARRAY) && "must be BYTE_ARRAY value");
+    size_t DataBitSize = DataSize * CHAR_BIT;
+    constexpr size_t SizeFieldSize = sizeof(SizeTy);
+    // Allocate space for size and data.
+    Val = new std::byte[SizeFieldSize + DataSize];
+
+    // Write the size into first bytes.
+    for (size_t I = 0; I < SizeFieldSize; ++I) {
+      auto ByteArrayVal = std::get<std::byte *>(Val);
+      ByteArrayVal[I] = (std::byte)DataBitSize;
+      DataBitSize >>= CHAR_BIT;
+    }
+    // Append data.
+    auto ByteArrayVal = std::get<std::byte *>(Val);
+    std::memcpy(ByteArrayVal + SizeFieldSize, V, DataSize);
+  }
+
+  Type getType() const { return Ty; }
+
+  SizeTy size() const {
+    switch (Ty) {
+    case UINT32:
+      return sizeof(uint32_t);
+    case BYTE_ARRAY:
+      return getRawByteArraySize();
+    default:
+      llvm_unreachable_internal("unsupported SYCL property type");
+    }
+  }
+
+private:
+  void copy(const SYCLPropertyValue &P);
+
+  Type Ty = NONE;
+  std::variant<uint32_t, std::byte *> Val;
----------------
llvm-beanz wrote:

It's a little redundant to store the type and a variant (which itself stores the type). Should this just be a union?

https://github.com/llvm/llvm-project/pull/110771