[lld] [lld][COFF] Support .pdata section on ARM64EC targets. (PR #72521)

[Martin Storsjö via llvm-commits]

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@@ -1665,10 +1689,15 @@ template <typename PEHeaderTy> void Writer::writeHeader() {
     dir[RESOURCE_TABLE].RelativeVirtualAddress = rsrcSec->getRVA();
     dir[RESOURCE_TABLE].Size = rsrcSec->getVirtualSize();
   }
-  if (firstPdata) {
-    dir[EXCEPTION_TABLE].RelativeVirtualAddress = firstPdata->getRVA();
-    dir[EXCEPTION_TABLE].Size =
-        lastPdata->getRVA() + lastPdata->getSize() - firstPdata->getRVA();
+  Chunk *firstPdataChunk =
+      ctx.config.machine == ARM64EC ? firstHybridPdata : firstPdata;
+  if (firstPdataChunk) {
+    Chunk *lastPdataChunk =
+        ctx.config.machine == ARM64EC ? lastHybridPdata : lastPdata;
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mstorsjo wrote:

Would it make this part of the code simpler, if you'd swap the roles of `firstPdata` and `firstHybridPdata`, having `firstPdata` point at the X64 unwind info, just like the data directory does, and `firstHybridPdata` point at the ARM64 unwind info?

https://github.com/llvm/llvm-project/pull/72521