[PATCH] D18226: Codegen: Tail-duplicate during placement.

[Kyle Butt via llvm-commits]

iteratee marked an inline comment as done.

================
Comment at: lib/CodeGen/TailDuplicator.cpp:572
@@ +571,3 @@
+    // the CFG.
+    HasIndirectbr = back.isIndirectBranch() && TailBB.succ_size() != 0;
+  }
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davidxl wrote:
> I don't get it. This one looks like a heuristic change to not give block with return instruction (as indirect branch) a larger threshold for duplication, which is independent of this patch.
I'll split these out, but they're all intertwined.

1. Don't duplicate latches/pre-headers early.
2. There are now tests that fail, so duplicate switches during layout.
3. Because the indirect branch test is now post Reg-Alloc, it has to handle the actual return instructions.


https://reviews.llvm.org/D18226