[PATCH] D43324: WIP: [Utils] Salvage debug info of DCE'ed extractvalue instructions

[Adrian Prantl via Phabricator via llvm-commits]

aprantl added inline comments.


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Comment at: lib/Transforms/Utils/Local.cpp:1601
+    // Rewrite the extractvalue by shifting away the unrelated bits of the
+    // aggregate operand.
+    Value *Agg = EVI->getAggregateOperand();
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Can you add a comment explaining why this is safe? I.e., because the size of the variable being described implicitly masks out the upper bits of the value..


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Comment at: lib/Transforms/Utils/Local.cpp:1605
+    unsigned FieldOffset = 0;
+    for (unsigned I = 0, E = FieldIndices.size(); I < E; ++I) {
+      Type *IndexedTy = ExtractValueInst::getIndexedType(
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Why does this loop go all the way to FieldIndices.size()?


https://reviews.llvm.org/D43324