[PATCH] D99079: [ARM][AArch64] Require appropriate features for crypto algorithms

[Tim Northover via Phabricator via llvm-commits]

t.p.northover added inline comments.


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Comment at: clang/lib/Driver/ToolChains/Arch/ARM.cpp:641
+      });
+  if ((ItSHA2 != Features.rend()) || (ItSHA2 != Features.rend()))
+    Features.push_back("-crypto");
----------------
Both of these checks are identical.

And could we get a comment on the purpose of this sequence? I think I can see mechanically what it's doing after a bit of thought, but still haven't come up with an example of the kind of problem it's trying to fix (not that I've tried terribly hard, that's what comments are for).


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Comment at: clang/lib/Driver/ToolChains/Arch/ARM.cpp:643
+    Features.push_back("-crypto");
+  if (ItSHA2 != Features.rend()) {
+    HasSHA2 = ItSHA2->take_front() == "+";
----------------
I think modifying `Features` above might have invalidated the iterator.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D99079/new/

https://reviews.llvm.org/D99079