[PATCH] D31924: SROA: Allow eliminating addrspacecasted allocas

[Eli Friedman via Phabricator via llvm-commits]

efriedma added inline comments.


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Comment at: docs/LangRef.rst:8460
+same memory location. The pointer conversion cannot be an arbitrarily
+complex value modification. For a defined result, the inverse cast to
+the original address space should yield the original pointer value.
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"The pointer conversion cannot be an arbitrarily complex value modification." is a bit vague... it'd be better if we could specifically say what transforms are allowed.


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Comment at: lib/Transforms/Scalar/SROA.cpp:1588
+    Ptr = IRB.CreatePointerBitCastOrAddrSpaceCast(Ptr, PointerTy,
+                                                  NamePrefix + "sroa_cast");
+  }
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Why do we want to generate an address-space cast here, as opposed to performing the memory operation using the alloca's natural address-space?


https://reviews.llvm.org/D31924