Remove the inttoptr dependency from load instructions.

Elides inttoptr casts used (exclusively) in load instructions when
PNaClVersion=2. This is an incremental start on removing the inttoptr
instruction from the PNaCl wire format (See issue 3544 for more information
on the strategy of removing ptrtoint).

Also modifies PNaCl bitcode reader/writer to accept PNaClVersion=1 as supported,
and PNaClVersion=2 as unsupported but readable (allowing pnacl-freeze and
pnacl-thaw to work on such files).

Also allows command-line option --pnacl-version for setting PNaClVersion in the
PNaCl bitcode writer.

Also fixes some problems on PNaCl bitcode headers, using common support to
determine when the read/written PNaCl bitcode file is valid.

BUG= https://code.google.com/p/nativeclient/issues/detail?id=3544
R=jvoung@chromium.org

Review URL: https://codereview.chromium.org/5812155903377408

1 files changed, 11 insertions, 0 deletions

diff --git a/lib/Bitcode/NaCl/Reader/NaClBitcodeReader.h b/lib/Bitcode/NaCl/Reader/NaClBitcodeReader.h
index 849ca7e506..805bddf0b2 100644
--- a/lib/Bitcode/NaCl/Reader/NaClBitcodeReader.h
+++ b/lib/Bitcode/NaCl/Reader/NaClBitcodeReader.h
@@ -267,6 +267,17 @@ private:
     return getFnValueByID(ValNo);
   }
 
+  /// \brief Add instructions to cast Op to the given type T into block BB.
+  /// Follows rules for pointer conversion as defined in
+  /// llvm/lib/Transforms/NaCl/ReplacePtrsWithInts.cpp.
+  ///
+  /// Returns 0 if unable to generate conversion value (also generates
+  /// an appropriate error message and calls Error).
+  Value *ConvertOpToType(Value *Op, Type *T, BasicBlock *BB);
+
+  /// \brief Install instruction I into basic block BB.
+  bool InstallInstruction(BasicBlock *BB, Instruction *I);
+
   bool ParseModule(bool Resume);
   bool ParseTypeTable();
   bool ParseTypeTableBody();