[llvm] [SjLjEHPrepare] Fix callsite problem (PR #67264)

[Matt Arsenault via llvm-commits]

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@@ -442,9 +442,19 @@ bool SjLjEHPrepare::setupEntryBlockAndCallSites(Function &F) {
   for (BasicBlock &BB : F) {
     if (&BB == &F.front())
       continue;
-    for (Instruction &I : BB)
-      if (I.mayThrow())
-        insertCallSiteStore(&I, -1);
+    for (Instruction &I : BB) {
+      // Partially revert b61fd7f modifications.  Stop using "I.mayThrow()"
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arsenm wrote:

Don't refer to past revert, explain what this is 

https://github.com/llvm/llvm-project/pull/67264