[clang] [llvm] [lld] [SHT_LLVM_BB_ADDR_MAP] Allow basic-block-sections and labels be used together by decoupling the handling of the two features. (PR #74128)

[Rahman Lavaee via cfe-commits]

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@@ -858,62 +899,64 @@ struct BBAddrMap {
     bool hasIndirectBranch() const { return MD.HasIndirectBranch; }
   };
 
-  BBAddrMap(uint64_t Addr, std::vector<BBEntry> BBEntries)
-      : Addr(Addr), BBEntries(std::move(BBEntries)) {}
+  // Struct representing the BBAddrMap information for a contiguous range of
+  // basic blocks (a function or a basic block section).
+  struct BBRangeEntry {
+    uint64_t BaseAddress;           // Base address of the range.
+    std::vector<BBEntry> BBEntries; // Basic block entries for this range.
+
+    // Equality operator for unit testing.
+    bool operator==(const BBRangeEntry &Other) const {
+      return BaseAddress == Other.BaseAddress &&
+             std::equal(BBEntries.begin(), BBEntries.end(),
+                        Other.BBEntries.begin());
+    }
+  };
 
-  // Returns the address of the corresponding function.
-  uint64_t getFunctionAddress() const { return Addr; }
+  // All ranges for this function. The first range always corresponds to the
+  // function entry.
+  std::vector<BBRangeEntry> BBRanges;
 
-  // Returns the basic block entries for this function.
-  const std::vector<BBEntry> &getBBEntries() const { return BBEntries; }
+  // Returns the function address associated with this BBAddrMap, which is
+  // stored as the `BaseAddress` of its first BBRangeEntry. Returns 0 if
+  // BBRanges is empty.
+  uint64_t getFunctionAddress() const {
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rlavaee wrote:

Changing the return type would change the API. So we would need to sequence this. How about an assertion? BBRanges should not be empty (except for tests).

https://github.com/llvm/llvm-project/pull/74128