[turbofan] Fix calls to computed code objects.

src/compiler/x64/code-generator-x64.cc

Index: src/compiler/x64/code-generator-x64.cc
diff --git a/src/compiler/x64/code-generator-x64.cc b/src/compiler/x64/code-generator-x64.cc
index 495470533d8f1595a38abff13919f2d6621138ae..8c4edeaf18d7f53b9a0a4f56c2130ccd73cb99a6 100644
--- a/src/compiler/x64/code-generator-x64.cc
+++ b/src/compiler/x64/code-generator-x64.cc
@@ -555,8 +555,8 @@ void CodeGenerator::AssembleArchInstruction(Instruction* instr) {
         __ Call(code, RelocInfo::CODE_TARGET);
       } else {
         Register reg = i.InputRegister(0);
-        int entry = Code::kHeaderSize - kHeapObjectTag;
-        __ Call(Operand(reg, entry));
+        __ addp(reg, Immediate(Code::kHeaderSize - kHeapObjectTag));
+        __ call(reg);
       }
       RecordCallPosition(instr);
       break;