Add a new method, described in the comment.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@19683 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2005-01-19 06:53:02 +00:00
parent 7c79de7c65
commit d7e2fe40e4

View File

@ -177,6 +177,18 @@ public:
return 0;
}
/// commuteInstruction - If a target has any instructions that are commutable,
/// but require converting to a different instruction or making non-trivial
/// changes to commute them, this method can overloaded to do this. The
/// default implementation of this method simply swaps the first two operands
/// of MI and returns it.
///
/// If a target wants to make more aggressive changes, they can construct and
/// return a new machine instruction. If an instruction cannot commute, it
/// can also return null.
///
virtual MachineInstr *commuteInstruction(MachineInstr *MI) const;
/// Insert a goto (unconditional branch) sequence to TMBB, at the
/// end of MBB
virtual void insertGoto(MachineBasicBlock& MBB,