Exemple #1
0
    virtual void visit(AstArraySel* nodep, AstNUser*) {
	if (!m_assignp) return;
	if (nodep->user3()) return;  // Prevent recursion on just created nodes
	unsigned dim = explicitDimensions(nodep);
	AstVarRef* refp = nodep->user1p()->castNode()->castVarRef();
	pair<uint32_t,uint32_t> arrDim = refp->varp()->dtypep()->dimensions(false);
	uint32_t implicit = (arrDim.second) - dim;
	if (implicit > 0) {
	    AstArraySel* newp = insertImplicit(nodep->cloneTree(false), dim+1, implicit);
	    nodep->replaceWith(newp); nodep = newp;
	    nodep->user3(true);
	}
	int clones = countClones(nodep);
	if (m_assignp->user2() > 0 && m_assignp->user2() != clones) {
	    m_assignp->v3error("Slices of arrays in assignments must have the same unpacked dimensions");
	} else if (!m_assignp->user2()) {
	    if (m_extend && clones > 1 && !m_assignError) {
		m_assignp->v3error("Unsupported: Assignment between unpacked arrays of different dimensions");
		m_assignError = true;
	    }
	    if (clones > 1 && !refp->lvalue() && refp->varp() == m_lhsVarRefp->varp()
		&& !m_assignp->castAssignDly() && !m_assignError) {
		// LHS Var != RHS Var for a non-delayed assignment
		m_assignp->v3error("Unsupported: Slices in a non-delayed assignment with the same Var on both sides");
		m_assignError = true;
	    }
	    m_assignp->user2(clones);
	}
    }
Exemple #2
0
    virtual void visit(AstVar* nodep, AstNUser*) {
	if (nodep->user2p()) {
	    // Make an assignment, so we'll trace it properly
	    // user2p is either a const or a var.
	    AstConst*  exprconstp  = nodep->user2p()->castNode()->castConst();
	    AstVarRef* exprvarrefp = nodep->user2p()->castNode()->castVarRef();
	    UINFO(8,"connectto: "<<nodep->user2p()->castNode()<<endl);
	    if (!exprconstp && !exprvarrefp) {
		nodep->v3fatalSrc("Unknown interconnect type; pinReconnectSimple should have cleared up\n");
	    }
	    if (exprconstp) {
		m_modp->addStmtp(new AstAssignW(nodep->fileline(),
						new AstVarRef(nodep->fileline(), nodep, true),
						exprconstp->cloneTree(true)));
	    } else if (nodep->user3()) {
		// Public variable at the lower module end - we need to make sure we propagate
		// the logic changes up and down; if we aliased, we might remove the change detection
		// on the output variable.
		UINFO(9,"public pin assign: "<<exprvarrefp<<endl);
		if (nodep->isInput()) nodep->v3fatalSrc("Outputs only - inputs use AssignAlias");
		m_modp->addStmtp(new AstAssignW(nodep->fileline(),
						new AstVarRef(nodep->fileline(), exprvarrefp->varp(), true),
						new AstVarRef(nodep->fileline(), nodep, false)));
	    } else if (nodep->isIfaceRef()) {
		m_modp->addStmtp(new AstAssignVarScope(nodep->fileline(),
						       new AstVarRef(nodep->fileline(), nodep, true),
						       new AstVarRef(nodep->fileline(), exprvarrefp->varp(), false)));
		AstNode* nodebp=exprvarrefp->varp();
		nodep ->fileline()->modifyStateInherit(nodebp->fileline());
		nodebp->fileline()->modifyStateInherit(nodep ->fileline());
	    } else {
		// Do to inlining child's variable now within the same module, so a AstVarRef not AstVarXRef below
		m_modp->addStmtp(new AstAssignAlias(nodep->fileline(),
						    new AstVarRef(nodep->fileline(), nodep, true),
						    new AstVarRef(nodep->fileline(), exprvarrefp->varp(), false)));
		AstNode* nodebp=exprvarrefp->varp();
		nodep ->fileline()->modifyStateInherit(nodebp->fileline());
		nodebp->fileline()->modifyStateInherit(nodep ->fileline());
	    }
	}
	// Variable under the inline cell, need to rename to avoid conflicts
	// Also clear I/O bits, as it is now local.
	string name = m_cellp->name() + "__DOT__" + nodep->name();
	if (!nodep->isFuncLocal()) nodep->inlineAttrReset(name);
	if (debug()>=9) { nodep->dumpTree(cout,"varchanged:"); }
	if (debug()>=9) { nodep->valuep()->dumpTree(cout,"varchangei:"); }
	// Iterate won't hit AstIfaceRefDType directly as it is no longer underneath the module
	if (AstIfaceRefDType* ifacerefp = nodep->dtypep()->castIfaceRefDType()) {
	    // Relink to point to newly cloned cell
	    if (ifacerefp->cellp()) {
		if (AstCell* newcellp = ifacerefp->cellp()->user4p()->castNode()->castCell()) {
		    ifacerefp->cellp(newcellp);
		    ifacerefp->cellName(newcellp->name());
		}
	    }
	}
	nodep->iterateChildren(*this);
    }
Exemple #3
0
    AstArraySel* insertImplicit(AstNode* nodep, unsigned start, unsigned count) {
	// Insert any implicit slices as explicit slices (ArraySel nodes).
	// Return a new pointer to replace nodep() in the ArraySel.
	UINFO(9,"  insertImplicit (start="<<start<<",c="<<count<<") "<<nodep<<endl);
	AstVarRef* refp = nodep->user1p()->castNode()->castVarRef();
	if (!refp) nodep->v3fatalSrc("No VarRef in user1 of node "<<nodep);
	AstVar* varp = refp->varp();
	AstNode* topp = nodep;
	for (unsigned i = start; i < start + count; ++i) {
	    AstNodeDType* dtypep = varp->dtypep()->dtypeDimensionp(i-1);
	    AstUnpackArrayDType* adtypep = dtypep->castUnpackArrayDType();
	    if (!adtypep) nodep->v3fatalSrc("insertImplicit tried to expand an array without an ArrayDType");
	    vlsint32_t msb = adtypep->msb();
	    vlsint32_t lsb = adtypep->lsb();
	    if (lsb > msb) {
		// Below code assumes big bit endian; just works out if we swap
		int x = msb; msb = lsb; lsb = x;
	    }
	    UINFO(9,"    ArraySel-child: "<<topp<<endl);
	    AstArraySel* newp = new AstArraySel(nodep->fileline(), topp,
						// "lsb-lsb": Arrays are zero-based so index 0 is always lsb
						new AstConst(nodep->fileline(), lsb-lsb));
	    if (!newp->dtypep()) {
		newp->v3fatalSrc("ArraySel dtyping failed when resolving slice");  // see ArraySel constructor
	    }
	    newp->user1p(refp);
	    newp->start(lsb);
	    newp->length(msb - lsb + 1);
	    topp = newp;
	}
	return topp->castArraySel();
    }
Exemple #4
0
    virtual void visit(AstPin* nodep, AstNUser*) {
	// Check to see if any output pins have __en pins and create the __en pins to match
	AstVarRef* refp = findVarRef(nodep);

	if (refp && refp->lvalue() && nodep->modVarp()->user1p()) {
	    AstVar* enchildp = (AstVar*)nodep->modVarp()->user1p();
	    UINFO(9, "       Pulling __en var" << enchildp << endl);
	    AstVar* enp = new AstVar(enchildp->fileline(),
				     AstVarType::OUTPUT,
				     enchildp->name()+cvtToStr(m_unique++),
				     enchildp);
	    enp->user2(enchildp->user2());
	    m_modp->addStmtp(enp);
	    AstPin* pinp = new AstPin(nodep->fileline(),
				      nodep->pinNum(),
				      enp->name(),
				      new AstVarRef(nodep->fileline(), enp, true));
	    AstVarRef *rp = findVarRef(pinp);
	    rp->replaceWith(new AstVarRef(nodep->fileline(), enp, true));
	    rp->deleteTree(); rp=NULL;
	    pinp->width(enp->width(),enp->width());  // minwidth==width
	    pinp->modVarp(enchildp);
	    m_cellp->addPinsp(pinp);
	    refp->user1p(enp);
	    refp->varp()->user1p(enp);
	}
	// Simplify interconnect in preperation for V3Inst
	// (This could be a separate visitor, but we're in the neighborhood)
	V3Inst::pinReconnectSimple(nodep, m_cellp, m_modp);
    }
 virtual void visit(AstSel* nodep, AstNUser*) {
     AstVarRef* varrefp = nodep->fromp()->castVarRef();
     AstConst* constp = nodep->lsbp()->castConst();
     if (varrefp && constp && !constp->num().isFourState()) {
         UndrivenVarEntry* entryp = getEntryp (varrefp->varp());
         int lsb = constp->toUInt();
         if (m_markBoth || varrefp->lvalue()) entryp->drivenBit(lsb, nodep->width());
         if (m_markBoth || !varrefp->lvalue()) entryp->usedBit(lsb, nodep->width());
     } else {
         // else other varrefs handled as unknown mess in AstVarRef
         nodep->iterateChildren(*this);
     }
 }
Exemple #6
0
    virtual void visit(AstPin* nodep, AstNUser*) {
	if (m_state == CONVERT_PINS) {
	    if (nodep->modVarp()->user1p()) {
		// create the input pin
		AstVarRef* refp = nodep->exprp()->castVarRef();
		if (!refp) nodep->v3fatal("Unsupported: Tristate pin not connected to simple net");
		AstVar* inp;
		if (refp->varp()->user1p()) { // this is a tristate
		    inp = (AstVar*) refp->varp()->user1p();
		} else {
		    inp = refp->varp();
		}
		AstPin* pinp = new AstPin(nodep->fileline(),
					  nodep->pinNum(),
					  nodep->name() + "__in",
					  new AstVarRef(nodep->fileline(), inp, false));
		m_cellp->addPinsp(pinp);

		// now link it
		pinp->modVarp((AstVar*) nodep->modVarp()->user1p());
	    }
	}
    }
Exemple #7
0
    // VISITORS
    virtual void visit(AstArraySel* nodep, AstNUser*) {
	if (!nodep->backp()->castArraySel()) {
	    // This is the top of an ArraySel, setup for iteration
	    m_refp = nodep->user1p()->castNode()->castVarRef();
	    m_vecIdx += 1;
	    if (m_vecIdx == (int)m_selBits.size()) {
		m_selBits.push_back(vector<unsigned>());
		AstVar* varp = m_refp->varp();
		pair<uint32_t,uint32_t> arrDim = varp->dtypep()->dimensions(false);
		uint32_t dimensions = arrDim.second;
		// for 3-dimensions we want m_selBits[m_vecIdx]=[0,0,0]
		for (uint32_t i = 0; i < dimensions; ++i) {
		    m_selBits[m_vecIdx].push_back(0);
		}
	    }
	}
	nodep->iterateChildren(*this);
	if (nodep->fromp()->castVarRef()) {
	    m_depth = 0;
	} else {
	    ++m_depth;
	}
	// Check if m_selBits has overflowed
	if (m_selBits[m_vecIdx][m_depth] >= nodep->length()) {
	    m_selBits[m_vecIdx][m_depth] = 0;
	    if (m_depth + 1 < m_selBits[m_vecIdx].size())
		m_selBits[m_vecIdx][m_depth+1] += 1;
	}
	// Reassign the bitp()
	if (nodep->length() > 1) {
	    if (AstConst* bitp = nodep->bitp()->castConst()) {
		AstUnpackArrayDType* adtypep = nodep->fromp()->dtypep()->skipRefp()->castUnpackArrayDType();
		if (!adtypep) nodep->v3fatalSrc("slice select tried to expand an array without an ArrayDType");
		unsigned idx = nodep->start() + m_selBits[m_vecIdx][m_depth] - adtypep->lsb();
		AstNode* constp = new AstConst(bitp->fileline(), V3Number(bitp->fileline(), bitp->castConst()->num().width(), idx));
		bitp->replaceWith(constp);
	    } else {
		nodep->v3error("Unsupported: Only constants supported in slices");
	    }
	}
	if (!nodep->backp()->castArraySel()) {
	    // Top ArraySel, increment m_selBits
	    m_selBits[m_vecIdx][0] += 1;
	}
	nodep->length(1);
    }
Exemple #8
0
    void expandUniOp(AstNodeUniop* nodep) {
	nodep->user1(true);
	unsigned dim = 0;
	if (AstArraySel* selp = nodep->lhsp()->castArraySel()) {
	    // We have explicit dimensions, either packed or unpacked
	    dim = explicitDimensions(selp);
	}
	if (dim == 0 && !nodep->lhsp()->castVarRef()) {
	    // No ArraySel nor VarRef, not something we can expand
	    nodep->iterateChildren(*this);
	} else {
	    AstVarRef* refp = findVarRefRecurse(nodep->lhsp());
	    ArrayDimensions varDim = refp->varp()->dtypep()->dimensions(false);
	    if ((int)(dim - varDim.second) < 0) {
		// Unpacked dimensions are referenced first, make sure we have them all
		nodep->v3error("Unary operator used across unpacked dimensions");
	    }
	}
    }
Exemple #9
0
    //*******************************************************************
    // The following visitor functions deal with detecting Z's in the
    // logic, stripping the Z's out and creating an __en signal and its
    // logic.
    //*******************************************************************
    virtual void visit(AstPull* nodep, AstNUser*) {
        // replace any pullup/pulldowns with assignw logic and an __en
        // signal just like it is any other tristate signal.  The only
        // difference is that the user2() variable on the __en signal
        // will be given a pull direction--i.e. pulldown=1, pullup=2.
        // This will signal the driver exansion logic to put a default
        // pullup or pulldown state on the tristate bus under the high-Z
        // condition when no one is driving the bus.  Given the complexity
        // of merging tristate drivers at any level, the current limitation
        // of this implementation is that a pullup/down gets applied
        // to all bits of a bus and a bus cannot have drivers in opposite
        // directions on indvidual pins.
        AstNode* outp = nodep->lhsp()->unlinkFrBack();;
        AstVarRef* outrefp = NULL;
	int width=-1;
	if (outp->castVarRef()) {
	    outrefp = outp->castVarRef();
	} else if (outp->castSel()) {
	    outrefp = outp->castSel()->fromp()->castVarRef();
	    width = outp->castSel()->widthConst();
	} else {
	    nodep->v3error("Can't find LHS varref");
	}
	outrefp->lvalue(true);
	AstVar* varp = outrefp->varp();
	if (width==-1) width=varp->width();

        V3Number num0 (nodep->fileline(), width);
	num0.setAllBits0();
	V3Number num1 (nodep->fileline(), width);
	num1.setAllBits1();

	AstConst* enrhsp = new AstConst(nodep->fileline(), num0);
	AstVar* enp = createEnableVar(outp, outrefp, enrhsp, width, "pull");
	enp->user2(nodep->direction()+1); // record the pull direction

	AstAssignW* newassp = new AstAssignW(nodep->fileline(), outp,
					     new AstConst(nodep->fileline(), nodep->direction() ? num1 : num0));
	nodep->replaceWith(newassp);
	nodep->deleteTree(); nodep=NULL;
	newassp->iterateChildren(*this);
    }
Exemple #10
0
    virtual void visit(AstVarRef* nodep, AstNUser*) {
	if (nodep->varp()->user2p()  // It's being converted to an alias.
	    && !nodep->varp()->user3()
	    && !nodep->backp()->castAssignAlias()) { 	// Don't constant propagate aliases (we just made)
	    AstConst*  exprconstp  = nodep->varp()->user2p()->castNode()->castConst();
	    AstVarRef* exprvarrefp = nodep->varp()->user2p()->castNode()->castVarRef();
	    if (exprconstp) {
		nodep->replaceWith(exprconstp->cloneTree(true));
		nodep->deleteTree(); nodep=NULL;
		return;
	    }
	    else if (exprvarrefp) {
		nodep->varp( exprvarrefp->varp() );
	    }
	    else {
		nodep->v3fatalSrc("Null connection?\n");
	    }
	}
	nodep->name(nodep->varp()->name());
	nodep->iterateChildren(*this);
    }
Exemple #11
0
    virtual void visit(AstSel* nodep, AstNUser*) {
	AstVarRef* varrefp = nodep->fromp()->castVarRef();
	AstConst* constp = nodep->lsbp()->castConst();
	if (varrefp && constp && !constp->num().isFourState()) {
	    for (int usr=1; usr<(m_alwaysp?3:2); ++usr) {
		UndrivenVarEntry* entryp = getEntryp (varrefp->varp(), usr);
		int lsb = constp->toUInt();
		if (m_markBoth || varrefp->lvalue()) {
		    // Don't warn if already driven earlier as "a=0; if(a) a=1;" is fine.
		    if (usr==2 && m_alwaysp && entryp->isUsedNotDrivenBit(lsb, nodep->width())) {
			UINFO(9," Select.  Entryp="<<(void*)entryp<<endl);
			warnAlwCombOrder(varrefp);
		    }
		    entryp->drivenBit(lsb, nodep->width());
		}
		if (m_markBoth || !varrefp->lvalue()) entryp->usedBit(lsb, nodep->width());
	    }
	} else {
	    // else other varrefs handled as unknown mess in AstVarRef
	    nodep->iterateChildren(*this);
	}
    }
Exemple #12
0
    virtual void visit(AstNodeModule* nodep, AstNUser*) {
	UINFO(9," MOD   "<<nodep<<endl);
	m_unique = 0;
	VarMap* lhsmapp = new VarMap();

	// expand tristate nodes and detect multiple LHS drivers for this module
	TristateExpander(nodep, lhsmapp);

	// iterate the children to grab any  __en signals from subcells
	m_modp = nodep;
	nodep->iterateChildren(*this);
	m_modp = NULL;

	// go through each multiple lhs driver & collapse it to a single driver
	for (VarMap::iterator nextit, it=lhsmapp->begin(); it != lhsmapp->end(); it=nextit) {
	    nextit = it; ++nextit;
	    m_unique = 0;
	    AstVar* lhsp = (*it).first;
	    RefVec* refs = (*it).second;
	    bool isOutput = (lhsp->varType() == AstVarType::OUTPUT) && (nodep->level() > 1); // force termination at top level

	    if (refs->size() < 2 && isOutput) {
		// if only one driver and this is an output, then exit and
		// let the driver propagate on its own.  If the signals
		// terminates at this level, then we need to let the
		// undriven state get generated.
		lhsmapp->erase(lhsp);
		delete refs;
		continue;
	    }


	    UINFO(9, "       Checking " << refs->size() << " drivers for tristates signals on net " << lhsp << endl);
	    int pull = 0;  // initially assume no pull direction

	    // Now remove and multple lhs signals that do not have __en for
	    // all possible drivers.
	    bool complete = true;
	    int found_one = 0;

	    for (RefVec::iterator ii=refs->begin(); ii != refs->end(); ++ii) {
		AstVarRef* refp = (*ii);
		if (!refp->user1p()) { // if no __en signal, then delete the entry
		    complete = false;
		} else {
		    found_one++;
		}
	    }
	    if (!complete) {
		if (found_one) {
		    UINFO(9, "       Problem mixing tristate and low-Z on " << lhsp << endl);
		    UINFO(9, "       Found " << found_one << " __en signals from of " << refs->size() << " possible drivers" << endl);
		    // not sure what I should do here other than error that they are mixing low-Z and tristate drivers.
		    // The other scenerio, and probably more likely, is that they are using a high-Z construct that
		    // is not supported.  Improving the high-Z detection logic will reduce the occurance of this failure.
		    nodep->v3error("Mixing tristate and low-Z drivers.  Perhaps you are using a high-Z construct not supported");
		} else  {
		    UINFO(9, "       No tristates found on " << lhsp <<endl);
		}
		lhsmapp->erase(lhsp);
		delete refs;
		continue;
	    }

	    UINFO(9, "       TRISTATE LHS DRIVER FOUND:" << lhsp << endl);

	    AstNode* orp = NULL,* andp = NULL,* undrivenp = NULL,* newenlogicp = NULL;

	    // loop through the lhs drivers to build the driver resolution logic
	    for (RefVec::iterator ii=refs->begin(); ii != refs->end(); ++ii) {
		AstVarRef* refp = (*ii);
		int w = lhsp->width();
		int wfill = 0; // width filler when necessary due to sels
		AstSel* selp = NULL;
		if (refp->user3p()) { // this varref has a sel
		    selp = (AstSel*) refp->user3p();
		    w = selp->widthConst();
		    wfill = lhsp->width() - w;
		}

		// create a new var for this assignment.
		AstVar* enp = (AstVar*)refp->user1p();
		AstVar* newlhsp = new AstVar(lhsp->fileline(),
					     AstVarType::MODULETEMP,
					     lhsp->name()+"__lhs"+cvtToStr(m_unique++),
					     AstLogicPacked(), w);
		nodep->addStmtp(newlhsp);

		// now append this driver to the driver logic.
		AstNode* ref1 = new AstVarRef(nodep->fileline(), newlhsp,false);
		AstNode* ref2 = new AstVarRef(nodep->fileline(), enp, false);
		andp = new AstAnd(nodep->fileline(), ref1, ref2);


		AstVar* bitselp = NULL;
		if (selp) { // this varref has a sel
		    int ws = V3Number::log2b(lhsp->width())+1;
		    bitselp = new AstVar(lhsp->fileline(),
					 AstVarType::MODULETEMP,
					 lhsp->name()+"__sel"+cvtToStr(m_unique-1),
					 AstLogicPacked(), ws);
		    //
		    nodep->addStmtp(bitselp);
		    nodep->addStmtp(new AstAssignW(lhsp->fileline(),
						   new AstVarRef(lhsp->fileline(), bitselp, true),
						   selp->lsbp()->cloneTree(false)));
		    andp = new AstShiftL(lhsp->fileline(),
					 new AstConcat(lhsp->fileline(), new AstConst(lhsp->fileline(), V3Number(lhsp->fileline(), wfill, 0)), andp),
					 new AstVarRef(lhsp->fileline(), bitselp, false),
					 lhsp->width()
			);

		    selp->replaceWith(new AstVarRef(refp->fileline(), newlhsp, true));
		    pushDeletep(selp);  // Setting selp here or deleting immediately
		    // breaks the t_tri_select test, this probably indicates a problem
		} else {
		    refp->varp(newlhsp); // assign the new var to the varref
		    refp->name(newlhsp->name());
		}

		// or this to the others
		orp = (!orp) ? andp : new AstOr(nodep->fileline(), orp, andp);

		if (isOutput) {
		    AstNode *en1p = new AstVarRef(nodep->fileline(), enp, false);
		    if (selp) {
			en1p = new AstShiftL(enp->fileline(),
					     new AstConcat(lhsp->fileline(), new AstConst(lhsp->fileline(), V3Number(lhsp->fileline(), wfill, 0)), en1p),
					     new AstVarRef(lhsp->fileline(), bitselp, false),
					     lhsp->width()
			    );
		    }
		    if (!newenlogicp) {
			newenlogicp = en1p;
		    } else {
			newenlogicp = new AstOr(nodep->fileline(), newenlogicp, en1p);
		    }
		} else {
		    if (!undrivenp) {
			undrivenp = new AstNot(nodep->fileline(), new AstVarRef(nodep->fileline(), enp, false));
			if (selp)
			    undrivenp = new AstShiftL(enp->fileline(),
						      new AstConcat(lhsp->fileline(), new AstConst(lhsp->fileline(), V3Number(lhsp->fileline(), wfill, 0)), undrivenp),
						      new AstVarRef(lhsp->fileline(), bitselp, false),
						      lhsp->width());
		    } else {
			AstNode *tmp = new AstNot(nodep->fileline(), new AstVarRef(nodep->fileline(), enp, false));
			if (selp) {
			    tmp = new AstShiftL(enp->fileline(),
						new AstConcat(lhsp->fileline(), new AstConst(lhsp->fileline(), V3Number(lhsp->fileline(), wfill, 0)), tmp),
						new AstVarRef(lhsp->fileline(), bitselp, false),
						lhsp->width());
			}
			undrivenp = new AstAnd(nodep->fileline(), tmp, undrivenp);
		    }
		}

		refp->user1p(NULL); // clear the user1p() as we done with it in the VarRef at this point

		if (enp->user2()) { // if this net is pulled up/down
		    int newpull = enp->user2();
		    if (pull == 0) {
			pull = newpull;
		    } else if (newpull != pull) {
			pull = -1; // conflict over the pull direction
		    }
		}
	    }
	    if (isOutput) {
		AstVar* newenp = new AstVar(lhsp->fileline(),
					    AstVarType::OUTPUT,
					    lhsp->name()+"__enout"+cvtToStr(m_unique++),
					    lhsp);
		nodep->addStmtp(newenp);
		nodep->addStmtp(new AstAssignW(lhsp->fileline(),
					       new AstVarRef(lhsp->fileline(), newenp, true),
					       newenlogicp));
		newenp->user2(pull); // put the pull direction in the next __en signal to pass it up
		lhsp->user1p(newenp); // put the new __en signal in the var so it can be pushed up the hierarchy.

	    } else { // this is the level where the signal terminates, we do final conflict resolution here
		UINFO(9, "       Terminating tristate logic for " << lhsp->name() << endl);
		UINFO(9, "       Pull direction is " << pull << " where -1=X, 0=Z, 1=low, 2=high." << endl);
		// figure out what to drive when no one is driving the bus
		V3Number num(nodep->fileline(), lhsp->width());
		if (pull==0) {
		    num.setAllBitsZ();
		} else if (pull==1) {
		    num.setAllBits0();
		} else if (pull==2) {
		    num.setAllBits1();
		} else {
		    num.setAllBitsX();
		}
		undrivenp = new AstAnd(nodep->fileline(), undrivenp,
				       new AstConst(nodep->fileline(), num));
		orp = new AstOr(nodep->fileline(), orp, undrivenp);
	    }
	    nodep->addStmtp(new AstAssignW(lhsp->fileline(),
					   new AstVarRef(lhsp->fileline(), lhsp, true), orp));

	    // delete the map and vector list now that we have collapsed it.
	    lhsmapp->erase(lhsp);
	    delete refs;
	}
	delete lhsmapp; // delete the map now that we are done
	nodep->user1p(NULL);
    }
    static AstAssignW* pinReconnectSimple(AstPin* pinp, AstCell* cellp, AstNodeModule*,
					  bool forTristate, bool alwaysCvt) {
	// If a pin connection is "simple" leave it as-is
	// Else create a intermediate wire to perform the interconnect
	// Return the new assignment, if one was made
	// Note this module calles cloneTree() via new AstVar
	AstVar* pinVarp = pinp->modVarp();
	AstVarRef* connectRefp = pinp->exprp()->castVarRef();
	AstBasicDType* pinBasicp = pinVarp->dtypep()->basicp();  // Maybe NULL
	AstBasicDType* connBasicp = NULL;
	AstAssignW* assignp = NULL;
	if (connectRefp) connBasicp = connectRefp->varp()->dtypep()->basicp();
	//
	if (!alwaysCvt
	    && connectRefp
	    && connectRefp->varp()->dtypep()->sameTree(pinVarp->dtypep())
	    && !connectRefp->varp()->isSc()) { // Need the signal as a 'shell' to convert types
	    // Done. Same data type
	} else if (!alwaysCvt
		   && connectRefp
		   && connectRefp->varp()->isIfaceRef()) {
	    // Done. Interface
	} else if (!alwaysCvt
		   && connBasicp
		   && pinBasicp
		   && connBasicp->width() == pinBasicp->width()
		   && connBasicp->lsb() == pinBasicp->lsb()
		   && !connectRefp->varp()->isSc()	// Need the signal as a 'shell' to convert types
		   && connBasicp->width() == pinVarp->width()
		   && 1) {
	    // Done. One to one interconnect won't need a temporary variable.
	} else if (!alwaysCvt && !forTristate && pinp->exprp()->castConst()) {
	    // Done. Constant.
	} else {
	    // Make a new temp wire
	    //if (1||debug()>=9) { pinp->dumpTree(cout,"-in_pin:"); }
	    AstNode* pinexprp = pinp->exprp()->unlinkFrBack();
	    string newvarname = ((string)(pinVarp->isOutput() ? "__Vcellout" : "__Vcellinp")
				 +(forTristate?"t":"")  // Prevent name conflict if both tri & non-tri add signals
				 +"__"+cellp->name()+"__"+pinp->name());
	    AstVar* newvarp = new AstVar (pinVarp->fileline(), AstVarType::MODULETEMP, newvarname, pinVarp);
	    // Important to add statement next to cell, in case there is a generate with same named cell
	    cellp->addNextHere(newvarp);
	    if (pinVarp->isInout()) {
		pinVarp->v3fatalSrc("Unsupported: Inout connections to pins must be direct one-to-one connection (without any expression)");
	    } else if (pinVarp->isOutput()) {
		// See also V3Inst
		AstNode* rhsp = new AstVarRef(pinp->fileline(), newvarp, false);
		UINFO(5,"pinRecon width "<<pinVarp->width()<<" >? "<<rhsp->width()<<" >? "<<pinexprp->width()<<endl);
		rhsp = extendOrSel (pinp->fileline(), rhsp, pinVarp);
		pinp->exprp(new AstVarRef (newvarp->fileline(), newvarp, true));
		AstNode* rhsSelp = extendOrSel (pinp->fileline(), rhsp, pinexprp);
		assignp = new AstAssignW (pinp->fileline(), pinexprp, rhsSelp);
	    } else {
		// V3 width should have range/extended to make the widths correct
		assignp = new AstAssignW (pinp->fileline(),
					  new AstVarRef(pinp->fileline(), newvarp, true),
					  pinexprp);
		pinp->exprp(new AstVarRef (pinexprp->fileline(), newvarp, false));
	    }
	    if (assignp) cellp->addNextHere(assignp);
	    //if (debug()) { pinp->dumpTree(cout,"-  out:"); }
	    //if (debug()) { assignp->dumpTree(cout,"- aout:"); }
	}
	return assignp;
    }
    bool forUnrollCheck(AstNode* nodep,
			AstNode* initp,	// Maybe under nodep (no nextp), or standalone (ignore nextp)
			AstNode* precondsp, AstNode* condp,
			AstNode* incp,		// Maybe under nodep or in bodysp
			AstNode* bodysp) {
	// To keep the IF levels low, we return as each test fails.
	UINFO(4, " FOR Check "<<nodep<<endl);
	if (initp)	UINFO(6, "    Init "<<initp<<endl);
	if (precondsp)	UINFO(6, "    Pcon "<<precondsp<<endl);
	if (condp)	UINFO(6, "    Cond "<<condp<<endl);
	if (incp)	UINFO(6, "    Inc  "<<incp<<endl);
	// Initial value check
	AstAssign* initAssp = initp->castAssign();
	if (!initAssp) return cantUnroll(nodep, "no initial assignment");
	if (initp->nextp() && initp->nextp()!=nodep) nodep->v3fatalSrc("initial assignment shouldn't be a list");
	if (!initAssp->lhsp()->castVarRef()) return cantUnroll(nodep, "no initial assignment to simple variable");
	m_forVarp = initAssp->lhsp()->castVarRef()->varp();
	m_forVscp = initAssp->lhsp()->castVarRef()->varScopep();
	if (nodep->castGenFor() && !m_forVarp->isGenVar()) {
	    nodep->v3error("Non-genvar used in generate for: "<<m_forVarp->name()<<endl);
	}
	if (m_generate) V3Const::constifyParamsEdit(initAssp->rhsp());  // rhsp may change
	AstConst* constInitp = initAssp->rhsp()->castConst();
	if (!constInitp) return cantUnroll(nodep, "non-constant initializer");
	//
	// Condition check
	if (condp->nextp()) nodep->v3fatalSrc("conditional shouldn't be a list");
	//
	// Assignment of next value check
	AstAssign* incAssp = incp->castAssign();
	if (!incAssp) return cantUnroll(nodep, "no increment assignment");
	if (incAssp->nextp()) nodep->v3fatalSrc("increment shouldn't be a list");
	AstNodeBiop* incInstrp = incAssp->rhsp()->castNodeBiop();
	//
	if (m_forVscp) { UINFO(8, "   Loop Variable: "<<m_forVscp<<endl); }
	else	       { UINFO(8, "   Loop Variable: "<<m_forVarp<<endl); }
	if (debug()>=9) nodep->dumpTree(cout,"-   for: ");
	//
	// Extract the constant loop bounds
	bool subtract = incInstrp->castSub();
	{
	    if (!subtract && !incInstrp->castAdd()) return cantUnroll(nodep, "missing add/sub for incrementer");
	    AstVarRef* incVarrp   = (subtract ? incInstrp->lhsp()->castVarRef()
				     : incInstrp->rhsp()->castVarRef());
	    if (!incVarrp) return cantUnroll(nodep, "missing variable in incrementer");
	    if (incVarrp->varp() != m_forVarp
		|| incVarrp->varScopep() != m_forVscp) {
		return cantUnroll(nodep, "different variables in incrementer");
	    }
	}
	//
	// Adds have the # on the lhsp because V3Const pushes rhs consts over to the lhs
	// Subtracts have it on the rhs, because you write i=i-1; i=1-i is non-sensible.
	AstConst* preconstIncp = (subtract ? incInstrp->rhsp()->castConst()
				  : incInstrp->lhsp()->castConst());
	if (m_generate) preconstIncp = V3Const::constifyParamsEdit(preconstIncp)->castConst();
	AstConst* constIncp = (subtract ? incInstrp->rhsp()->castConst()
			       : incInstrp->lhsp()->castConst());
	UINFO(8, "   Inc expr ok:  "<<constIncp<<endl);
	if (!constIncp) return cantUnroll(nodep, "non-constant increment");
	if (constIncp->isZero()) return cantUnroll(nodep, "zero increment");  // Or we could loop forever below...

        bool lt  = condp->castLt() || condp->castLtS();
        bool lte = condp->castLte() || condp->castLteS();
	bool gt  = condp->castGt() || condp->castGtS();
	bool gte = condp->castGte() || condp->castGteS();
	if (!lt && !lte && !gt && !gte)
	    return cantUnroll(nodep, "condition not <= or <");
	AstNodeBiop* condBip = condp->castNodeBiop();
	if (!condBip->lhsp()->castVarRef())
	    return cantUnroll(nodep, "no variable on lhs of condition");
	if (condBip->lhsp()->castVarRef()->varp() != m_forVarp
	    || condBip->lhsp()->castVarRef()->varScopep() != m_forVscp)
	    return cantUnroll(nodep, "different variable in condition");
	if (m_generate) V3Const::constifyParamsEdit(condBip->rhsp());  // rhsp may change
	AstConst* constStopp = condBip->rhsp()->castConst();
	if (!constStopp) return cantUnroll(nodep, "non-constant final value");
	UINFO(8, "   Stop expr ok: "<<constStopp<<endl);
	//
	if (constInitp->width()>32 || constInitp->num().isFourState()
	    || constStopp->width()>32 || constStopp->num().isFourState()
	    || constIncp->width()>32  || constIncp->num().isFourState())
	    return cantUnroll(nodep, "init/final/increment too large or four state");
	vlsint32_t valInit = constInitp->num().toSInt();
	vlsint32_t valStop = constStopp->num().toSInt();
	if (lte) valStop++;  if (gte) valStop--;
	vlsint32_t valInc  = constIncp->num().toSInt();
	if (subtract) valInc = -valInc;
	UINFO(8,"     In Numbers: for (v="<<valInit<<"; v<"<<valStop<<"; v=v+"<<valInc<<")\n");
	//
	if (!m_generate) {
	    int loops = ((valStop - valInit)/valInc);
	    if (loops < 0) { loops += (1ULL<<constStopp->width()); } // Will roll around
	    UINFO(8, "         ~Iters: "<<loops<<" c="<<unrollCount()<<endl);
	    if (loops > unrollCount())
		return cantUnroll(nodep, "too many iterations");

	    // Less than 10 statements in the body?
	    int bodySize = 0;
	    int bodyLimit = v3Global.opt.unrollStmts();
	    if (loops>0) bodyLimit = v3Global.opt.unrollStmts() / loops;
	    if (bodySizeOverRecurse(precondsp, bodySize/*ref*/, bodyLimit)
		|| bodySizeOverRecurse(bodysp, bodySize/*ref*/, bodyLimit)
		|| bodySizeOverRecurse(incp, bodySize/*ref*/, bodyLimit)) {
		return cantUnroll(nodep, "too many statements");
	    }
	}
	//
	// Now, make sure there's no assignment to this variable in the loop
	m_varModeCheck = true;
	m_varAssignHit = false;
	m_ignoreIncp = incp;
	precondsp->iterateAndNext(*this);
	bodysp->iterateAndNext(*this);
	incp->iterateAndNext(*this);
	m_varModeCheck = false;
	m_ignoreIncp = NULL;
	if (m_varAssignHit) return cantUnroll(nodep, "genvar assigned *inside* loop");
	//
	// Finally, we can do it
	forUnroller(nodep, initp, precondsp, condp, incp, bodysp,
		    constInitp->num(),
		    condBip, constStopp->num(),
		    incInstrp, constIncp->num()); nodep = NULL;
	// Cleanup
	return true;
    }
Exemple #15
0
void V3Inst::pinReconnectSimple(AstPin* pinp, AstCell* cellp, AstNodeModule* modp) {
    // If a pin connection is "simple" leave it as-is
    // Else create a intermediate wire to perform the interconnect
    // Note this module calles cloneTree() via new AstVar
    AstVar* pinVarp = pinp->modVarp();
    AstVarRef* connectRefp = pinp->exprp()->castVarRef();
    AstBasicDType* pinBasicp = pinVarp->dtypep()->basicp();  // Maybe NULL
    AstBasicDType* connBasicp = NULL;
    if (connectRefp) connBasicp = connectRefp->varp()->dtypep()->basicp();
    //
    if (connectRefp
	&& connectRefp->varp()->dtypep()->sameTree(pinVarp->dtypep())
	&& !connectRefp->varp()->isSc()) { // Need the signal as a 'shell' to convert types
	// Done.  Same data type
    } else if (connBasicp
	       && pinBasicp
	       && connBasicp->width() == pinBasicp->width()
	       && connBasicp->lsb() == pinBasicp->lsb()
	       && !connectRefp->varp()->isSc()	// Need the signal as a 'shell' to convert types
	       && pinp->width() == pinVarp->width()
	       && 1) {
	// Done. One to one interconnect won't need a temporary variable.
    } else if (pinp->exprp()->castConst()) {
	// Done. Constant.
    } else {
	// Make a new temp wire
	//if (1||debug()>=9) { pinp->dumpTree(cout,"in_pin:"); }
	AstAssignW* assignp = NULL;
	AstNode* pinexprp = pinp->exprp()->unlinkFrBack();
	string newvarname = "__Vcellinp__"+cellp->name()+"__"+pinp->name();
	AstVar* newvarp = new AstVar (pinVarp->fileline(), AstVarType::MODULETEMP, newvarname, pinVarp);
	modp->addStmtp(newvarp);
	if (pinVarp->isInout()) {
	    pinVarp->v3fatalSrc("Unsupported: Inout connections to pins must be direct one-to-one connection (without any expression)");
	} else if (pinVarp->isOutput()) {
	    // See also V3Inst
	    AstNode* rhsp = new AstVarRef(pinp->fileline(), newvarp, false);
	    if (pinp->width() > rhsp->width()) {
		if (rhsp->isSigned()) {
		    rhsp = new AstExtendS(pinp->fileline(), rhsp);
		} else {
		    rhsp = new AstExtend (pinp->fileline(), rhsp);
		}
	    } else if (pinp->width() < rhsp->width()) {
		rhsp = new AstSel    (pinp->fileline(), rhsp, 0, pinp->width());
	    }
	    rhsp->widthSignedFrom(pinp);
	    assignp = new AstAssignW (pinp->fileline(), pinexprp, rhsp);
	    pinp->exprp(new AstVarRef (pinexprp->fileline(), newvarp, true));
	} else {
	    // V3 width should have range/extended to make the widths correct
	    if (pinexprp->width() != pinVarp->width()) pinp->v3fatalSrc("Input pin width mismatch");
	    assignp = new AstAssignW (pinp->fileline(),
				      new AstVarRef(pinp->fileline(), newvarp, true),
				      pinexprp);
	    pinp->exprp(new AstVarRef (pinexprp->fileline(), newvarp, false));
	}
	pinp->widthSignedFrom(pinp->exprp());
	if (assignp) modp->addStmtp(assignp);
	//if (1||debug()) { pinp->dumpTree(cout,"  out:"); }
	//if (1||debug()) { assignp->dumpTree(cout," aout:"); }
    }
}
Exemple #16
0
    AstNode* createDlyArray(AstAssignDly* nodep, AstNode* lhsp) {
	// Create delayed assignment
	// See top of this file for transformation
	// Return the new LHS for the assignment, Null = unlink
	// Find selects
	AstNode* newlhsp = NULL;	// NULL = unlink old assign
	AstSel*  bitselp = NULL;
	AstArraySel*  arrayselp = NULL;
	if (lhsp->castSel()) {
	    bitselp = lhsp->castSel();
	    arrayselp = bitselp->fromp()->castArraySel();
	} else {
	    arrayselp = lhsp->castArraySel();
	}
	if (!arrayselp) nodep->v3fatalSrc("No arraysel under bitsel?");
	if (arrayselp->length()!=1) nodep->v3fatalSrc("ArraySel with length!=1 should have been removed in V3Slice");

	UINFO(4,"AssignDlyArray: "<<nodep<<endl);
	//
	//=== Dimensions: __Vdlyvdim__
	deque<AstNode*> dimvalp;		// Assignment value for each dimension of assignment
	AstNode* dimselp=arrayselp;
	for (; dimselp->castArraySel(); dimselp=dimselp->castArraySel()->fromp()) {
	    AstNode* valp = dimselp->castArraySel()->bitp()->unlinkFrBack();
	    dimvalp.push_front(valp);
	}
	AstVarRef* varrefp = dimselp->castVarRef();
	if (!varrefp) nodep->v3fatalSrc("No var underneath arraysels\n");
	if (!varrefp->varScopep()) varrefp->v3fatalSrc("Var didn't get varscoped in V3Scope.cpp\n");
	varrefp->unlinkFrBack();
	AstVar* oldvarp = varrefp->varp();
	int modVecNum = oldvarp->user4();  oldvarp->user4(modVecNum+1);
	//
	deque<AstNode*> dimreadps;		// Read value for each dimension of assignment
	for (unsigned dimension=0; dimension<dimvalp.size(); dimension++) {
	    AstNode* dimp = dimvalp[dimension];
	    if (dimp->castConst()) { // bit = const, can just use it
		dimreadps.push_front(dimp);
	    } else {
		string bitvarname = (string("__Vdlyvdim")+cvtToStr(dimension)
				     +"__"+oldvarp->shortName()+"__v"+cvtToStr(modVecNum));
		AstVarScope* bitvscp = createVarSc(varrefp->varScopep(), bitvarname, dimp->width());
		AstAssign* bitassignp
		    = new AstAssign (nodep->fileline(),
				     new AstVarRef(nodep->fileline(), bitvscp, true),
				     dimp);
		nodep->addNextHere(bitassignp);
		dimreadps.push_front(new AstVarRef(nodep->fileline(), bitvscp, false));
	    }
	}
	//
	//=== Bitselect: __Vdlyvlsb__
	AstNode* bitreadp=NULL;  // Code to read Vdlyvlsb
	if (bitselp) {
	    AstNode* lsbvaluep = bitselp->lsbp()->unlinkFrBack();
	    if (bitselp->fromp()->castConst()) {// vlsb = constant, can just push constant into where we use it
		bitreadp = lsbvaluep;
	    } else {
		string bitvarname = (string("__Vdlyvlsb__")+oldvarp->shortName()+"__v"+cvtToStr(modVecNum));
		AstVarScope* bitvscp = createVarSc(varrefp->varScopep(), bitvarname, lsbvaluep->width());
		AstAssign* bitassignp = new AstAssign (nodep->fileline(),
						       new AstVarRef(nodep->fileline(), bitvscp, true),
						       lsbvaluep);
		nodep->addNextHere(bitassignp);
		bitreadp = new AstVarRef(nodep->fileline(), bitvscp, false);
	    }
	}
	//
	//=== Value: __Vdlyvval__
	AstNode* valreadp;	// Code to read Vdlyvval
	if (nodep->rhsp()->castConst()) {	// vval = constant, can just push constant into where we use it
	    valreadp = nodep->rhsp()->unlinkFrBack();
	} else {
	    string valvarname = (string("__Vdlyvval__")+oldvarp->shortName()+"__v"+cvtToStr(modVecNum));
	    AstVarScope* valvscp = createVarSc(varrefp->varScopep(), valvarname, nodep->rhsp()->width());
	    newlhsp = new AstVarRef(nodep->fileline(), valvscp, true);
	    valreadp = new AstVarRef(nodep->fileline(), valvscp, false);
	}
	//
	//=== Setting/not setting boolean: __Vdlyvset__
	AstVarScope* setvscp;
	AstAssignPre* setinitp = NULL;

	if (nodep->user3p()) {
	    // Simplistic optimization.  If the previous statement in same scope was also a =>,
	    // then we told this nodep->user3 we can use its Vdlyvset rather than making a new one.
	    // This is good for code like:
	    //    for (i=0; i<5; i++)  vector[i] <= something;
	    setvscp = nodep->user3p()->castNode()->castVarScope();
	    ++m_statSharedSet;
	} else {  // Create new one
	    string setvarname = (string("__Vdlyvset__")+oldvarp->shortName()+"__v"+cvtToStr(modVecNum));
	    setvscp = createVarSc(varrefp->varScopep(), setvarname, 1);
	    setinitp = new AstAssignPre (nodep->fileline(),
					 new AstVarRef(nodep->fileline(), setvscp, true),
					 new AstConst(nodep->fileline(), 0));
	    AstAssign* setassignp
		= new AstAssign (nodep->fileline(),
				 new AstVarRef(nodep->fileline(), setvscp, true),
				 new AstConst(nodep->fileline(),
					      V3Number(nodep->fileline(),1,true)));
	    nodep->addNextHere(setassignp);
	}
	if (m_nextDlyp) {  // Tell next assigndly it can share the variable
	    m_nextDlyp->user3p(setvscp);
	}
	//
	// Create ALWAYSPOST for delayed variable
	// We add all logic to the same block if it's for the same memory
	// This insures that multiple assignments to the same memory will result
	// in correctly ordered code - the last assignment must be last.
	// It also has the nice side effect of assisting cache locality.
	AstNode* selectsp = varrefp;
	for (int dimension=int(dimreadps.size())-1; dimension>=0; --dimension) {
	    selectsp = new AstArraySel(nodep->fileline(), selectsp, dimreadps[dimension]);
	}
	if (bitselp) {
	    selectsp = new AstSel(nodep->fileline(), selectsp, bitreadp,
				  bitselp->widthp()->cloneTree(false));
	}
	// Build "IF (changeit) ...
	UINFO(9,"   For "<<setvscp<<endl);
	UINFO(9,"     & "<<varrefp<<endl);
	AstAlwaysPost* finalp = varrefp->varScopep()->user4p()->castNode()->castAlwaysPost();
	if (finalp) {
	    AstActive* oldactivep = finalp->user2p()->castNode()->castActive();
	    checkActivePost(varrefp, oldactivep);
	    if (setinitp) oldactivep->addStmtsp(setinitp);
	} else { // first time we've dealt with this memory
	    finalp = new AstAlwaysPost(nodep->fileline(), NULL/*sens*/, NULL/*body*/);
	    UINFO(9,"     Created "<<finalp<<endl);
	    AstActive* newactp = createActivePost(varrefp);
	    newactp->addStmtsp(finalp);
	    varrefp->varScopep()->user4p(finalp);
	    finalp->user2p(newactp);
	    if (setinitp) newactp->addStmtsp(setinitp);
	}
	AstIf* postLogicp;
	if (finalp->user3p()->castNode() == setvscp) {
	    // Optimize as above; if sharing Vdlyvset *ON SAME VARIABLE*,
	    // we can share the IF statement too
	    postLogicp = finalp->user4p()->castNode()->castIf();
	    if (!postLogicp) nodep->v3fatalSrc("Delayed assignment misoptimized; prev var found w/o associated IF");
	} else {
	    postLogicp = new AstIf (nodep->fileline(),
				    new AstVarRef(nodep->fileline(), setvscp, false),
				    NULL,
				    NULL);
	    UINFO(9,"     Created "<<postLogicp<<endl);
	    finalp->addBodysp(postLogicp);
	    finalp->user3p(setvscp);	// Remember IF's vset variable
	    finalp->user4p(postLogicp);	// and the associated IF, as we may be able to reuse it
	}
	postLogicp->addIfsp(new AstAssign(nodep->fileline(), selectsp, valreadp));
	return newlhsp;
    }