[PATCH] D40230: Add -mprefer-vector-width driver option and attribute during CodeGen.

[Sanjay Patel via Phabricator via cfe-commits]

spatel added a reviewer: hfinkel.
spatel added inline comments.


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Comment at: include/clang/Frontend/CodeGenOptions.h:254
 
+  /// The prefered vector width.
+  std::string PreferVectorWidth;
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typo - 'preferred'. Should add a bit more to the explanation. "The preferred width for auto-vectorization transforms. This is intended to override default transforms based on the width of the architected vector registers." ?


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Comment at: lib/Driver/ToolChains/Clang.cpp:277
 
+/// The -mpreferred
+static void ParseMPreferVectorWidth(const Driver &D, const ArgList &Args,
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Comment got chopped off? Should we also include an explanation in the clang manual?


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Comment at: lib/Driver/ToolChains/Clang.cpp:285-286
+  StringRef Value = A->getValue();
+  if (Value == "none") {
+    CmdArgs.push_back("-mprefer-vector-width=none");
+  } else {
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What is the intended functionality when specifying 'none'? If it's equivalent to passing "-vectorize-slp" + "-vectorize-loops", can we use the existing flags?


https://reviews.llvm.org/D40230