-The first miri task that I took on was for miri to do something sensible with MIR's [`StroageLive` and `StroageDead` statements](https://github.com/solson/miri/issues/49).
-If you haven't seen these before, that's because they do not come up in Rust code; instead, `StroageLive` and `StroageDead` are inserted by the compiler.
+The first miri task that I took on was for miri to do something sensible with MIR's [`StorageLive` and `StorageDead` statements](https://github.com/solson/miri/issues/49).
+If you haven't seen these before, that's because they do not come up in Rust code; instead, `StorageLive` and `StorageDead` are inserted by the compiler.
Liveness information is important because it is forwarded to LLVM, which then uses this information to allocate variables into stack slots.
If two variables are never live at the same time, the compiler can assign both of them the *same* slot, which is great because it makes the stack frame smaller.
Liveness information is important because it is forwarded to LLVM, which then uses this information to allocate variables into stack slots.
If two variables are never live at the same time, the compiler can assign both of them the *same* slot, which is great because it makes the stack frame smaller.
-To this end, rustc will translate `StorageLive` to [`llvm.lifetime.start`](http://llvm.org/docs/LangRef.html#llvm-lifetime-start-intrinsic) and `StroageDead` to [`llvm.lifetime.end`](http://llvm.org/docs/LangRef.html#llvm-lifetime-end-intrinsic).
+To this end, rustc will translate `StorageLive` to [`llvm.lifetime.start`](http://llvm.org/docs/LangRef.html#llvm-lifetime-start-intrinsic) and `StorageDead` to [`llvm.lifetime.end`](http://llvm.org/docs/LangRef.html#llvm-lifetime-end-intrinsic).
-At this point, I ended up in a lengthy discussion with @eddyb and @arielb1, who both know approximately infinitely more about LLVM and rustc than I do, and this is how the third option in the list arose:
+At this point, I ended up in a lengthy discussion with @eddyb and @arielb1 and some folks in #rustc, who know approximately infinitely more about LLVM and rustc than I do, and this is how the third option in the list arose:
When performing `StorageLive` on a variable that already is live, forget the value that is currently in the local variable, but otherwise keep it live.
This is consistent with what we have caught LLVM doing.
It is hard to get any more definite than this.
When performing `StorageLive` on a variable that already is live, forget the value that is currently in the local variable, but otherwise keep it live.
This is consistent with what we have caught LLVM doing.
It is hard to get any more definite than this.
The good news is that with this choice of MIR semantics, miri's test suite passes.
We can thus be sure (well, insofar as the test suite is representative -- this will hopefully get better over time) that rustc produces code that follows our new rules.
The good news is that with this choice of MIR semantics, miri's test suite passes.
We can thus be sure (well, insofar as the test suite is representative -- this will hopefully get better over time) that rustc produces code that follows our new rules.
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