[llvm] [C API] Add blockaddress getters to C API (PR #77390)

[Nikita Popov via llvm-commits]

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@@ -373,6 +387,22 @@ static LLVMValueRef clone_constant_impl(LLVMValueRef Cst, LLVMModuleRef M) {
     return LLVMConstVector(Elts.data(), EltCount);
   }
 
+  if (LLVMIsABlockAddress(Cst)) {
+    check_value_kind(Cst, LLVMBlockAddressValueKind);
+    LLVMValueRef SrcFunc = LLVMGetBlockAddressFunction(Cst);
+    LLVMBasicBlockRef SrcBB = LLVMGetBlockAddressBasicBlock(Cst);
+
+    LLVMValueRef DstFunc = clone_constant(SrcFunc, M);
+
+    LLVMBasicBlockRef DstBB =
+        find_bb_in_func(DstFunc, LLVMGetBasicBlockName(SrcBB));
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nikic wrote:

This approach is not going to work for unnamed blocks.

https://github.com/llvm/llvm-project/pull/77390