[llvm] [JumpThreading] Copy metadata when inserting preload into preds (PR #134403)

[Yingwei Zheng via llvm-commits]

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@@ -1409,6 +1409,13 @@ bool JumpThreadingPass::simplifyPartiallyRedundantLoad(LoadInst *LoadI) {
     if (AATags)
       NewVal->setAAMetadata(AATags);
 
+    if (auto *MD = LoadI->getMetadata(LLVMContext::MD_invariant_load))
+      NewVal->setMetadata(LLVMContext::MD_invariant_load, MD);
+    if (auto *InvGroupMD = LoadI->getMetadata(LLVMContext::MD_invariant_group))
+      NewVal->setMetadata(LLVMContext::MD_invariant_group, InvGroupMD);
+    if (auto *RangeMD = LoadI->getMetadata(LLVMContext::MD_range))
+      NewVal->setMetadata(LLVMContext::MD_range, RangeMD);
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dtcxzyw wrote:

>  We could only call it for the !isGuaranteedToTransferExecutionToSuccessor case.
I don't think preserving invariant_load is valid for the non-guaranteed-to-transfer case, at least with the currently specified semantics.

It is guaranteed by previous checks:
https://github.com/llvm/llvm-project/blob/35f4cdbf59fca82b97869cce7e9e5d5009144938/llvm/lib/Transforms/Scalar/JumpThreading.cpp#L1357-L1369
https://github.com/llvm/llvm-project/blob/35f4cdbf59fca82b97869cce7e9e5d5009144938/llvm/lib/Transforms/Scalar/GVN.cpp#L1727-L1730


https://github.com/llvm/llvm-project/pull/134403