[llvm] [Offloading] Extend OffloadBinary format to support multiple metadata entries (PR #169425)

[Yury Plyakhin via llvm-commits]

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@@ -109,9 +109,12 @@ class OffloadBinary : public Binary {
   struct Header {
     uint8_t Magic[4] = {0x10, 0xFF, 0x10, 0xAD}; // 0x10FF10AD magic bytes.
     uint32_t Version = OffloadBinary::Version;   // Version identifier.
-    uint64_t Size;        // Size in bytes of this entire binary.
-    uint64_t EntryOffset; // Offset of the metadata entry in bytes.
-    uint64_t EntrySize;   // Size of the metadata entry in bytes.
+    uint64_t Size;          // Size in bytes of this entire binary.
+    uint64_t EntriesCount;  // Number of metadata entries in the binary.
+    uint64_t EntriesOffset; // Offset in bytes to the start of entries block.
+    uint64_t EntriesSize;   // Size of the entries block in bytes.
+    uint64_t StringOffset;  // Offset in bytes to the global string map
+    uint64_t NumStrings;    // Number of entries in the global string map.
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YuriPlyakhin wrote:

Yes, this introduces a global string map for data that is associated with the entire binary. Example when we would need it is to save bundle state: https://registry.khronos.org/SYCL/specs/sycl-2020/html/sycl-2020.html#sec:interfaces.bundles.bundlestate

https://github.com/llvm/llvm-project/pull/169425