- Add getLSDAEncoding to the PowerPC backend.
- Greatly improve the comments to the getLSDAEncoding method.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93796 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/PowerPC/PPCTargetMachine.h b/lib/Target/PowerPC/PPCTargetMachine.h
index 3399ac8..4afcb23 100644
--- a/lib/Target/PowerPC/PPCTargetMachine.h
+++ b/lib/Target/PowerPC/PPCTargetMachine.h
@@ -62,6 +62,18 @@
     return &MachOWriterInfo;
   }
 
+  /// getLSDAEncoding - Returns the LSDA pointer encoding. The choices are
+  /// 4-byte, 8-byte, and target default. The CIE is hard-coded to indicate that
+  /// the LSDA pointer in the FDE section is an "sdata4", and should be encoded
+  /// as a 4-byte pointer by default. However, some systems may require a
+  /// different size due to bugs or other conditions. We will default to a
+  /// 4-byte encoding unless the system tells us otherwise.
+  ///
+  /// FIXME: This call-back isn't good! We should be using the correct encoding
+  /// regardless of the system. However, there are some systems which have bugs
+  /// that prevent this from occuring.
+  virtual DwarfLSDAEncoding::Encoding getLSDAEncoding() const;
+
   // Pass Pipeline Configuration
   virtual bool addInstSelector(PassManagerBase &PM, CodeGenOpt::Level OptLevel);
   virtual bool addPreEmitPass(PassManagerBase &PM, CodeGenOpt::Level OptLevel);