[PATCH] D121897: Support phi operand in __builtin_object_size folder

[Nikita Popov via Phabricator via llvm-commits]

nikic added a reviewer: nikic.
nikic added inline comments.


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Comment at: llvm/lib/Analysis/MemoryBuiltins.cpp:816
+SizeOffsetType ObjectSizeOffsetVisitor::visitPHINode(PHINode &PN) {
   // too complex to analyze statically.
+  SmallVector<std::pair<SizeOffsetType, APInt>> Results;
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Comment can be dropped.


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Comment at: llvm/lib/Analysis/MemoryBuiltins.cpp:839
+        ->first;
+  }
+
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Support for Exact mode?

It might be worthwhile to phrase this in terms of `combine(SizeOffsetType, SizeOffsetType, EvalMode) -> SizeOffsetType` and reuse that between the Select and the PHINode handling.


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Comment at: llvm/test/Transforms/InstCombine/builtin-object-size-phi.ll:1
+; RUN: opt -O1 -S < %s | FileCheck %s
+
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This should run `-instcombine` only.


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D121897/new/

https://reviews.llvm.org/D121897