MachineCSE: Add a target query for the LookAheadLimit heurisitic
This is used to determine whether or not to CSE physical register
defs.
Differential Revision: http://reviews.llvm.org/D9472
llvm-svn: 236923
diff --git a/llvm/lib/Target/R600/SIInstrInfo.h b/llvm/lib/Target/R600/SIInstrInfo.h
index 7e049dc..f952c0f 100644
--- a/llvm/lib/Target/R600/SIInstrInfo.h
+++ b/llvm/lib/Target/R600/SIInstrInfo.h
@@ -142,6 +142,8 @@
bool FoldImmediate(MachineInstr *UseMI, MachineInstr *DefMI,
unsigned Reg, MachineRegisterInfo *MRI) const final;
+ unsigned getMachineCSELookAheadLimit() const override { return 500; }
+
bool isSALU(uint16_t Opcode) const {
return get(Opcode).TSFlags & SIInstrFlags::SALU;
}