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

[Joseph Huber 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.
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jhuber6 wrote:

Realistically I think the one thing we need is an entry size so that we know how far to skip past the image. Right now I think the size is only for the contained image, so we don't know when the next image would start. Keeping the changes minimal means fewer things to update, like the YAML to OBJ handling

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