CfgTraits was reverted almost two weeks ago upstream but will presumably
come back. See: e025d09b216dc2239e1b502f4f277abb6fb4648a
The PPC MMA clang types were added nine days ago.
The stdlib is still crashing deep in LLVM:
```
swifterror value can only be loaded and stored from, or as a swifterror argument!
%swift.error** %2
%7 = bitcast %swift.error** %2 to %swift.opaque*
in function $ss7DecoderP16unkeyedContainers015UnkeyedDecodingC0_pyKFTj
```
From a lldb session, the function in question:
```
define protected swiftcc void @"$ss7DecoderP16unkeyedContainers015UnkeyedDecodingC0_pyKFTj"(%Ts24UnkeyedDecodingContainerP* noalias nocapture sret %0, %swift.opaque* noalias nocapture swiftself %1, %swift.error** noalias nocapture swifterror dereferenceable(8) %2, %swift.type* %3, i8** %4) #0 {
%6 = bitcast %Ts24UnkeyedDecodingContainerP* %0 to %swift.opaque*
%7 = bitcast %swift.error** %2 to %swift.opaque*
tail call swiftcc void @"$sSK5index6before5IndexQzAD_tFTj"(%swift.opaque* noalias nocapture sret %6, %swift.opaque* noalias nocapture %1, %swift.opaque* noalias nocapture swiftself %7, %swift.type* %3, i8** %4) #0
ret void
}
```
This adds the typedef and switches uses of NodeType * to NodeRef. This is in
preparation for the eventual NodeRef-ization of the GraphTraits in LLVM. NFC.
TerminatorInsts. Now you can walk over the successor list of a terminator
and actually modify the SILSuccessor directly, allowing better CFG
transformations. NFC.
Swift SVN r26140
type, though; I had to define a WriteAsOperand function and
add a front() method to SILFunction to get this to work.
Rip out my dominators implementation and replace it with
LLVM's. I'd forgotten that LLVM's was actually generic.
Swift SVN r4717
