[llvm-commits] [llvm] r134219 - in /llvm/trunk: include/llvm/MC/SubtargetFeature.h lib/MC/SubtargetFeature.cpp

[Eli Friedman]

On Thu, Jun 30, 2011 at 5:23 PM, Evan Cheng <evan.cheng at apple.com> wrote:
> Author: evancheng
> Date: Thu Jun 30 19:23:10 2011
> New Revision: 134219
>
> URL: http://llvm.org/viewvc/llvm-project?rev=134219&view=rev
> Log:
> Switch SubtargetFeatures from std::string to StringRef.
>
> Modified:
>    llvm/trunk/include/llvm/MC/SubtargetFeature.h
>    llvm/trunk/lib/MC/SubtargetFeature.cpp
>
[...]
> @@ -53,16 +53,19 @@
>
>  /// PrependFlag - Return a string with a prepended flag; '+' or '-'.
>  ///
> -static inline std::string PrependFlag(const std::string &Feature,
> -                                      bool IsEnabled) {
> +static inline StringRef PrependFlag(const StringRef Feature,
> +                                    bool IsEnabled) {
>   assert(!Feature.empty() && "Empty string");
> -  if (hasFlag(Feature)) return Feature;
> -  return std::string(IsEnabled ? "+" : "-") + Feature;
> +  if (hasFlag(Feature))
> +    return Feature;
> +  std::string Prefix = IsEnabled ? "+" : "-";
> +  Prefix += Feature;
> +  return StringRef(Prefix);
>  }

Use-after-free.

> -std::string SubtargetFeatures::getString() const {
> +StringRef SubtargetFeatures::getString() const {
>   return Join(Features);
>  }

Same.

-Eli