Simplify RegScavenger::FindUnusedReg.

- Drop the Candidates argument and fix all callers. Now that RegScavenger
  tracks available registers accurately, there is no need to restict the
  search.
- Make sure that no aliases of the found register are in use. This was a potential bug.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@79369 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 2 insertions, 8 deletions

diff --git a/include/llvm/CodeGen/RegisterScavenging.h b/include/llvm/CodeGen/RegisterScavenging.h
index 6a15fcf065..511b8bb784 100644
--- a/include/llvm/CodeGen/RegisterScavenging.h
+++ b/include/llvm/CodeGen/RegisterScavenging.h
@@ -98,15 +98,9 @@ public:
   /// getRegsUsed - return all registers currently in use in used.
   void getRegsUsed(BitVector &used, bool includeReserved);
 
-  /// FindUnusedReg - Find a unused register of the specified register class
-  /// from the specified set of registers. It return 0 is none is found.
-  unsigned FindUnusedReg(const TargetRegisterClass *RegClass,
-                         const BitVector &Candidates) const;
-
   /// FindUnusedReg - Find a unused register of the specified register class.
-  /// Exclude callee saved registers if directed. It return 0 is none is found.
-  unsigned FindUnusedReg(const TargetRegisterClass *RegClass,
-                         bool ExCalleeSaved = false) const;
+  /// Return 0 if none is found.
+  unsigned FindUnusedReg(const TargetRegisterClass *RegClass) const;
 
   /// setScavengingFrameIndex / getScavengingFrameIndex - accessor and setter of
   /// ScavengingFrameIndex.