Change target-specific classes to use more precise static types.
This eliminates the need for several awkward casts, including
the last dynamic_cast under lib/Target.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@51091 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/Alpha/Alpha.h b/lib/Target/Alpha/Alpha.h
index 40725af..77b404f 100644
--- a/lib/Target/Alpha/Alpha.h
+++ b/lib/Target/Alpha/Alpha.h
@@ -25,7 +25,7 @@
   class MachineCodeEmitter;
 
   FunctionPass *createAlphaSimpleInstructionSelector(TargetMachine &TM);
-  FunctionPass *createAlphaISelDag(TargetMachine &TM);
+  FunctionPass *createAlphaISelDag(AlphaTargetMachine &TM);
   FunctionPass *createAlphaCodePrinterPass(std::ostream &OS,
                                              TargetMachine &TM);
   FunctionPass *createAlphaPatternInstructionSelector(TargetMachine &TM);