[llvm] [MachineBlockPlacement][X86] Use max of MDAlign and TLIAlign to align Loops. (PR #71026)

[Vito Kortbeek via llvm-commits]

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@@ -151,6 +151,53 @@ MachineLoopInfo::findLoopPreheader(MachineLoop *L, bool SpeculativePreheader,
   return Preheader;
 }
 
+MDNode *MachineLoop::getLoopID() const {
+  MDNode *LoopID = nullptr;
+  if (const auto *MBB = findLoopControlBlock()) {
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kortbeek-snps wrote:

Thanks for the quick response, @FreddyLeaf!

I don't see this reflected in the `Loop::setLoopID` function in the middle-end [llvm/lib/Analysis/LoopInfo.cpp#L526](https://github.com/llvm/llvm-project/blob/8a53324aa5c98787fe2334180a26b426f793d139/llvm/lib/Analysis/LoopInfo.cpp#L526), and the `llvm.loop` documentation also only mentions that the loop metadata is connected to the branch instruction in the loop latch (https://llvm.org/docs/LangRef.html#llvm-loop). Is this exception documented somewhere?

https://github.com/llvm/llvm-project/pull/71026