Add call instructions to Subzero's bitcode reader.

src/IceInst.h

Index: src/IceInst.h
diff --git a/src/IceInst.h b/src/IceInst.h
index 18c38dd29da78b01b7038ecb9672fcf325b9a789..e28d69cc8297ba45ef745d792efbd8f06decf6b9 100644
--- a/src/IceInst.h
+++ b/src/IceInst.h
@@ -296,32 +296,36 @@ private:
 class InstCall : public Inst {
 public:
   static InstCall *create(Cfg *Func, SizeT NumArgs, Variable *Dest,
-                          Operand *CallTarget) {
+                          Operand *CallTarget, bool hasTailCall = false) {

[Jim Stichnoth, 2014/09/18 21:41:54]

Can you make this a non-default argument?  I think there's only one other place
that would need to be changed.

[Karl, 2014/09/18 22:01:50]

Done.

     // Set HasSideEffects to true so that the call instruction can't be
     // dead-code eliminated. IntrinsicCalls can override this if the
     // particular intrinsic is deletable and has no side-effects.
     const bool HasSideEffects = true;
     const InstKind Kind = Inst::Call;
-    return new (Func->allocateInst<InstCall>())
-        InstCall(Func, NumArgs, Dest, CallTarget, HasSideEffects, Kind);
+    return new (Func->allocateInst<InstCall>()) InstCall(
+        Func, NumArgs, Dest, CallTarget, hasTailCall, HasSideEffects, Kind);
   }
   void addArg(Operand *Arg) { addSource(Arg); }
   Operand *getCallTarget() const { return getSrc(0); }
   Operand *getArg(SizeT I) const { return getSrc(I + 1); }
   SizeT getNumArgs() const { return getSrcSize() - 1; }
+  bool isTailcall() const { return hasTailCall; }
   virtual void dump(const Cfg *Func) const;
   static bool classof(const Inst *Inst) { return Inst->getKind() == Call; }
+  Type getReturnType() const;
 
 protected:
   InstCall(Cfg *Func, SizeT NumArgs, Variable *Dest, Operand *CallTarget,
-           bool HasSideEff, InstKind Kind)
+           bool HasTailCl, bool HasSideEff, InstKind Kind)

[jvoung (off chromium), 2014/09/18 22:04:46]

nit: I think we might as well just make the argument name "HasTailCall" and
"HasSideEffects"?

[Karl, 2014/09/19 20:29:51]

I agree with using HasTailCall. Changing field back.

       : Inst(Func, Kind, NumArgs + 1, Dest) {
+    hasTailCall = HasTailCl;
     HasSideEffects = HasSideEff;
     addSource(CallTarget);
   }
   virtual ~InstCall() {}
 
 private:
+  bool hasTailCall;

[Jim Stichnoth, 2014/09/18 21:41:54]

Capitalize per LLVM convention.

Also, small nit - isn't it more proper to say it *is* a tail call, rather than
it *has* a tail call?

So may I suggest:
  IsTailCall for the field name
  TailCall for the create()/ctor arg

[Karl, 2014/09/18 22:01:50]

Done.

   InstCall(const InstCall &) LLVM_DELETED_FUNCTION;
   InstCall &operator=(const InstCall &) LLVM_DELETED_FUNCTION;
 };
@@ -475,7 +479,7 @@ public:
 private:
   InstIntrinsicCall(Cfg *Func, SizeT NumArgs, Variable *Dest,
                     Operand *CallTarget, const Intrinsics::IntrinsicInfo &Info)
-      : InstCall(Func, NumArgs, Dest, CallTarget, Info.HasSideEffects,
+      : InstCall(Func, NumArgs, Dest, CallTarget, false, Info.HasSideEffects,
                  Inst::IntrinsicCall),
         Info(Info) {}
   InstIntrinsicCall(const InstIntrinsicCall &) LLVM_DELETED_FUNCTION;