Reserve space for PHI nodes when we read them in. This provides a VERY

tasty 15% speedup on the testcase from Bill.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@8993 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Bytecode/Reader/InstructionReader.cpp

@@ -125,6 +125,7 @@ Instruction *BytecodeParser::ParseInstruction(const unsigned char *&Buf,
       throw std::string("Invalid phi node encountered!\n");
 
     PHINode *PN = new PHINode(InstTy);
+    PN->op_reserve(Args.size());
     for (unsigned i = 0, e = Args.size(); i != e; i += 2)
       PN->addIncoming(getValue(RI.Type, Args[i]), getBasicBlock(Args[i+1]));
     return PN;