C++ AstNodeModule::varNumGetInc方法代码示例

    void createDeepTemp(AstNode* nodep) {
	UINFO(6,"  Deep  "<<nodep<<endl);
	//if (debug()>=9) nodep->dumpTree(cout,"deep:");

	string newvarname = ((string)"__Vdeeptemp"+cvtToStr(m_modp->varNumGetInc()));
	AstVar* varp = new AstVar (nodep->fileline(), AstVarType::STMTTEMP, newvarname,
				   // Width, not widthMin, as we may be in middle of BITSEL expression which
				   // though it's one bit wide, needs the mask in the upper bits.
				   // (Someday we'll have a valid bitmask instead of widths....)
				   // See t_func_crc for an example test that requires this
				   VFlagLogicPacked(), nodep->width());
	if (!m_funcp) nodep->v3fatalSrc("Deep expression not under a function");
	m_funcp->addInitsp(varp);
	// Replace node tree with reference to var
	AstVarRef* newp = new AstVarRef (nodep->fileline(), varp, false);
	nodep->replaceWith(newp);
	// Put assignment before the referencing statement
	AstAssign* assp = new AstAssign (nodep->fileline(),
					 new AstVarRef(nodep->fileline(), varp, true),
					 nodep);
	AstNRelinker linker2;
	m_stmtp->unlinkFrBack(&linker2);
	assp->addNext(m_stmtp);
	linker2.relink(assp);
    }

    AstVar* getBlockTemp(AstNode* nodep) {
	string newvarname = ((string)"__Vtemp"+cvtToStr(m_modp->varNumGetInc()));
	AstVar* varp = new AstVar (nodep->fileline(), AstVarType::STMTTEMP, newvarname,
				   nodep->dtypep());
	m_funcp->addInitsp(varp);
	return varp;
    }

    void replaceBoundLvalue(AstNode* nodep, AstNode* condp) {
	// Spec says a out-of-range LHS SEL results in a NOP.
	// This is a PITA.  We could:
	//  1. IF(...) around an ASSIGN,
	//     but that would break a "foo[TOO_BIG]=$fopen(...)".
	//  2. Hack to extend the size of the output structure
	//     by one bit, and write to that temporary, but never read it.
	//     That makes there be two widths() and is likely a bug farm.
	//  3. Make a special SEL to choose between the real lvalue
	//     and a temporary NOP register.
	//  4. Assign to a temp, then IF that assignment.
	//     This is suspected to be nicest to later optimizations.
	// 4 seems best but breaks later optimizations.  3 was tried,
	// but makes a mess in the emitter as lvalue switching is needed.  So 4.
	// SEL(...) -> temp
	//             if (COND(LTE(bit<=maxlsb))) ASSIGN(SEL(...)),temp)
	if (m_assignwp) {
	    // Wire assigns must become always statements to deal with insertion
	    // of multiple statements.  Perhaps someday make all wassigns into always's?
	    UINFO(5,"     IM_WireRep  "<<m_assignwp<<endl);
	    m_assignwp->convertToAlways(); pushDeletep(m_assignwp); m_assignwp=NULL;
	}
	bool needDly = (m_assigndlyp != NULL);
	if (m_assigndlyp) {
	    // Delayed assignments become normal assignments,
	    // then the temp created becomes the delayed assignment
	    AstNode* newp = new AstAssign(m_assigndlyp->fileline(),
					  m_assigndlyp->lhsp()->unlinkFrBackWithNext(),
					  m_assigndlyp->rhsp()->unlinkFrBackWithNext());
	    m_assigndlyp->replaceWith(newp); pushDeletep(m_assigndlyp); m_assigndlyp=NULL;
	}
	AstNode* prep = nodep;

	// Scan back to put the condlvalue above all selects (IE top of the lvalue)
	while (prep->backp()->castNodeSel()
	       || prep->backp()->castSel()) {
	    prep=prep->backp();
	}
	FileLine* fl = nodep->fileline();
	VL_DANGLING(nodep);  // Zap it so we don't use it by mistake - use prep

	// Already exists; rather than IF(a,... IF(b... optimize to IF(a&&b,
	// Saves us teaching V3Const how to optimize, and it won't be needed again.
	if (AstIf* ifp = prep->user2p()->castIf()) {
	    if (needDly) prep->v3fatalSrc("Should have already converted to non-delay");
	    AstNRelinker replaceHandle;
	    AstNode* earliercondp = ifp->condp()->unlinkFrBack(&replaceHandle);
	    AstNode* newp = new AstLogAnd (condp->fileline(),
					   condp,
					   earliercondp);
	    UINFO(4, "Edit BOUNDLVALUE "<<newp<<endl);
	    replaceHandle.relink(newp);
	}
	else {
	    string name = ((string)"__Vlvbound"+cvtToStr(m_modp->varNumGetInc()));
	    AstVar* varp = new AstVar(fl, AstVarType::MODULETEMP, name,
				      prep->dtypep());
	    m_modp->addStmtp(varp);

	    AstNode* abovep = prep->backp();  // Grab above point before lose it w/ next replace
	    prep->replaceWith(new AstVarRef(fl, varp, true));
	    AstNode* newp = new AstIf(fl, condp,
				      (needDly
				       ? static_cast<AstNode*>
				       (new AstAssignDly(fl, prep,
							 new AstVarRef(fl, varp, false)))
				       : static_cast<AstNode*>
				       (new AstAssign   (fl, prep,
							 new AstVarRef(fl, varp, false)))),
				      NULL);
	    if (debug()>=9) newp->dumpTree(cout,"     _new: ");
	    abovep->addNextStmt(newp,abovep);
	    prep->user2p(newp);  // Save so we may LogAnd it next time
	}
    }

    virtual void visit(AstConst* nodep) {
	if (m_constXCvt
	    && nodep->num().isFourState()) {
	    UINFO(4," CONST4 "<<nodep<<endl);
	    if (debug()>=9) nodep->dumpTree(cout,"  Const_old: ");
	    // CONST(num) -> VARREF(newvarp)
	    //		-> VAR(newvarp)
	    //		-> INITIAL(VARREF(newvarp, OR(num_No_Xs,AND(random,num_1s_Where_X))
	    V3Number numb1 (nodep->fileline(), nodep->width());
	    numb1.opBitsOne(nodep->num());
	    V3Number numbx (nodep->fileline(), nodep->width());
	    numbx.opBitsXZ(nodep->num());
	    if (v3Global.opt.xAssign()!="unique") {
		// All X bits just become 0; fastest simulation, but not nice
		V3Number numnew (nodep->fileline(), numb1.width());
		if (v3Global.opt.xAssign()=="1") {
		    numnew.opOr(numb1, numbx);
		} else {
		    numnew.opAssign(numb1);
		}
		AstConst* newp = new AstConst(nodep->fileline(), numnew);
		nodep->replaceWith(newp);
		nodep->deleteTree(); VL_DANGLING(nodep);
		UINFO(4,"   -> "<<newp<<endl);
	    } else {
		// Make a Vxrand variable
		// We use the special XTEMP type so it doesn't break pure functions
		if (!m_modp) nodep->v3fatalSrc("X number not under module");
		string newvarname = ((string)"__Vxrand"
				     +cvtToStr(m_modp->varNumGetInc()));
		AstVar* newvarp
		    = new AstVar (nodep->fileline(), AstVarType::XTEMP, newvarname,
				  VFlagLogicPacked(), nodep->width());
		++m_statUnkVars;
		AstNRelinker replaceHandle;
		nodep->unlinkFrBack(&replaceHandle);
		AstNodeVarRef* newref1p = new AstVarRef(nodep->fileline(), newvarp, false);
		replaceHandle.relink(newref1p);	    // Replace const with varref
		AstInitial* newinitp
		    = new AstInitial(
			nodep->fileline(),
			new AstAssign(
			    nodep->fileline(),
			    new AstVarRef(nodep->fileline(), newvarp, true),
			    new AstOr(nodep->fileline(),
				      new AstConst(nodep->fileline(),numb1),
				      new AstAnd(nodep->fileline(),
						 new AstConst(nodep->fileline(),numbx),
						 new AstRand(nodep->fileline(),
							     nodep->dtypep(), true)))));
		// Add inits in front of other statement.
		// In the future, we should stuff the initp into the module's constructor.
		AstNode* afterp = m_modp->stmtsp()->unlinkFrBackWithNext();
		m_modp->addStmtp(newvarp);
		m_modp->addStmtp(newinitp);
		m_modp->addStmtp(afterp);
		if (debug()>=9) newref1p->dumpTree(cout,"     _new: ");
		if (debug()>=9) newvarp->dumpTree(cout,"     _new: ");
		if (debug()>=9) newinitp->dumpTree(cout,"     _new: ");
		nodep->deleteTree(); VL_DANGLING(nodep);
	    }
	}
    }