Recommit "[GlobalISel] Import patterns containing INSERT_SUBREG"

I thought `llvm::sort` was stable for some reason but it's not.

Use `llvm::stable_sort` in `CodeGenTarget::getSuperRegForSubReg`.

Original patch: https://reviews.llvm.org/D66498

llvm-svn: 370084

1 files changed, 6 insertions, 0 deletions

diff --git a/llvm/utils/TableGen/CodeGenTarget.h b/llvm/utils/TableGen/CodeGenTarget.h
index 1ab2de269c7..d52ffac4ce6 100644
--- a/llvm/utils/TableGen/CodeGenTarget.h
+++ b/llvm/utils/TableGen/CodeGenTarget.h
@@ -103,6 +103,12 @@ public:
   /// getRegBank - Return the register bank description.
   CodeGenRegBank &getRegBank() const;
 
+  /// Return the largest register class on \p RegBank which supports \p Ty and
+  /// covers \p SubIdx if it exists.
+  Optional<CodeGenRegisterClass *>
+  getSuperRegForSubReg(const ValueTypeByHwMode &Ty, CodeGenRegBank &RegBank,
+                       const CodeGenSubRegIndex *SubIdx) const;
+
   /// getRegisterByName - If there is a register with the specific AsmName,
   /// return it.
   const CodeGenRegister *getRegisterByName(StringRef Name) const;