forked from github/verilator
296 lines
9.6 KiB
C++
296 lines
9.6 KiB
C++
// -*- mode: C++; c-file-style: "cc-mode" -*-
|
||
//*************************************************************************
|
||
// DESCRIPTION: Verilator: LValue module/signal name references
|
||
//
|
||
// Code available from: http://www.veripool.org/verilator
|
||
//
|
||
//*************************************************************************
|
||
//
|
||
// Copyright 2003-2019 by Wilson Snyder. This program is free software; you can
|
||
// redistribute it and/or modify it under the terms of either the GNU
|
||
// Lesser General Public License Version 3 or the Perl Artistic License
|
||
// Version 2.0.
|
||
//
|
||
// Verilator is distributed in the hope that it will be useful,
|
||
// but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||
// GNU General Public License for more details.
|
||
//
|
||
//*************************************************************************
|
||
// LinkLValue TRANSFORMATIONS:
|
||
// Top-down traversal
|
||
// Set lvalue() attributes on appropriate VARREFs.
|
||
//*************************************************************************
|
||
|
||
#include "config_build.h"
|
||
#include "verilatedos.h"
|
||
|
||
#include "V3Global.h"
|
||
#include "V3LinkLValue.h"
|
||
#include "V3Ast.h"
|
||
|
||
#include <algorithm>
|
||
#include <cstdarg>
|
||
#include <map>
|
||
#include <vector>
|
||
|
||
//######################################################################
|
||
// Link state, as a visitor of each AstNode
|
||
|
||
class LinkLValueVisitor : public AstNVisitor {
|
||
private:
|
||
// NODE STATE
|
||
|
||
// STATE
|
||
bool m_setRefLvalue; // Set VarRefs to lvalues for pin assignments
|
||
AstNodeFTask* m_ftaskp; // Function or task we're inside
|
||
|
||
// METHODS
|
||
VL_DEBUG_FUNC; // Declare debug()
|
||
|
||
// VISITs
|
||
// Result handing
|
||
virtual void visit(AstNodeVarRef* nodep) {
|
||
// VarRef: LValue its reference
|
||
if (m_setRefLvalue) {
|
||
nodep->lvalue(true);
|
||
}
|
||
if (nodep->varp()) {
|
||
if (nodep->lvalue() && !m_ftaskp
|
||
&& nodep->varp()->isReadOnly()) {
|
||
nodep->v3warn(ASSIGNIN, "Assigning to input/const variable: "
|
||
<<nodep->prettyNameQ());
|
||
}
|
||
}
|
||
iterateChildren(nodep);
|
||
}
|
||
|
||
// Nodes that start propagating down lvalues
|
||
virtual void visit(AstPin* nodep) {
|
||
if (nodep->modVarp() && nodep->modVarp()->isWritable()) {
|
||
// When the varref's were created, we didn't know the I/O state
|
||
// Now that we do, and it's from a output, we know it's a lvalue
|
||
m_setRefLvalue = true;
|
||
iterateChildren(nodep);
|
||
m_setRefLvalue = false;
|
||
} else {
|
||
iterateChildren(nodep);
|
||
}
|
||
}
|
||
virtual void visit(AstNodeAssign* nodep) {
|
||
bool last_setRefLvalue = m_setRefLvalue;
|
||
{
|
||
m_setRefLvalue = true;
|
||
iterateAndNextNull(nodep->lhsp());
|
||
m_setRefLvalue = false;
|
||
iterateAndNextNull(nodep->rhsp());
|
||
}
|
||
m_setRefLvalue = last_setRefLvalue;
|
||
}
|
||
virtual void visit(AstFOpen* nodep) {
|
||
bool last_setRefLvalue = m_setRefLvalue;
|
||
{
|
||
m_setRefLvalue = true;
|
||
iterateAndNextNull(nodep->filep());
|
||
m_setRefLvalue = false;
|
||
iterateAndNextNull(nodep->filenamep());
|
||
iterateAndNextNull(nodep->modep());
|
||
}
|
||
m_setRefLvalue = last_setRefLvalue;
|
||
}
|
||
virtual void visit(AstFClose* nodep) {
|
||
bool last_setRefLvalue = m_setRefLvalue;
|
||
{
|
||
m_setRefLvalue = true;
|
||
iterateAndNextNull(nodep->filep());
|
||
}
|
||
m_setRefLvalue = last_setRefLvalue;
|
||
}
|
||
virtual void visit(AstFFlush* nodep) {
|
||
bool last_setRefLvalue = m_setRefLvalue;
|
||
{
|
||
m_setRefLvalue = true;
|
||
iterateAndNextNull(nodep->filep());
|
||
}
|
||
m_setRefLvalue = last_setRefLvalue;
|
||
}
|
||
virtual void visit(AstFGetC* nodep) {
|
||
bool last_setRefLvalue = m_setRefLvalue;
|
||
{
|
||
m_setRefLvalue = true;
|
||
iterateAndNextNull(nodep->filep());
|
||
}
|
||
m_setRefLvalue = last_setRefLvalue;
|
||
}
|
||
virtual void visit(AstFGetS* nodep) {
|
||
bool last_setRefLvalue = m_setRefLvalue;
|
||
{
|
||
m_setRefLvalue = true;
|
||
iterateAndNextNull(nodep->filep());
|
||
iterateAndNextNull(nodep->strgp());
|
||
}
|
||
m_setRefLvalue = last_setRefLvalue;
|
||
}
|
||
virtual void visit(AstFRead* nodep) {
|
||
bool last_setRefLvalue = m_setRefLvalue;
|
||
{
|
||
m_setRefLvalue = true;
|
||
iterateAndNextNull(nodep->memp());
|
||
iterateAndNextNull(nodep->filep());
|
||
}
|
||
m_setRefLvalue = last_setRefLvalue;
|
||
}
|
||
virtual void visit(AstFScanF* nodep) {
|
||
bool last_setRefLvalue = m_setRefLvalue;
|
||
{
|
||
m_setRefLvalue = true;
|
||
iterateAndNextNull(nodep->filep());
|
||
iterateAndNextNull(nodep->exprsp());
|
||
}
|
||
m_setRefLvalue = last_setRefLvalue;
|
||
}
|
||
virtual void visit(AstSScanF* nodep) {
|
||
bool last_setRefLvalue = m_setRefLvalue;
|
||
{
|
||
m_setRefLvalue = true;
|
||
iterateAndNextNull(nodep->exprsp());
|
||
}
|
||
m_setRefLvalue = last_setRefLvalue;
|
||
}
|
||
virtual void visit(AstSysIgnore* nodep) {
|
||
// Can't know if lvalue or not; presume so as stricter
|
||
bool last_setRefLvalue = m_setRefLvalue;
|
||
iterateChildren(nodep);
|
||
m_setRefLvalue = last_setRefLvalue;
|
||
}
|
||
virtual void visit(AstReadMem* nodep) {
|
||
bool last_setRefLvalue = m_setRefLvalue;
|
||
{
|
||
m_setRefLvalue = true;
|
||
iterateAndNextNull(nodep->memp());
|
||
m_setRefLvalue = false;
|
||
iterateAndNextNull(nodep->filenamep());
|
||
iterateAndNextNull(nodep->lsbp());
|
||
iterateAndNextNull(nodep->msbp());
|
||
}
|
||
m_setRefLvalue = last_setRefLvalue;
|
||
}
|
||
virtual void visit(AstValuePlusArgs* nodep) {
|
||
bool last_setRefLvalue = m_setRefLvalue;
|
||
{
|
||
m_setRefLvalue = false;
|
||
iterateAndNextNull(nodep->searchp());
|
||
m_setRefLvalue = true;
|
||
iterateAndNextNull(nodep->outp());
|
||
}
|
||
m_setRefLvalue = last_setRefLvalue;
|
||
}
|
||
virtual void visit(AstSFormat* nodep) {
|
||
bool last_setRefLvalue = m_setRefLvalue;
|
||
{
|
||
m_setRefLvalue = true;
|
||
iterateAndNextNull(nodep->lhsp());
|
||
m_setRefLvalue = false;
|
||
iterateAndNextNull(nodep->fmtp());
|
||
}
|
||
m_setRefLvalue = last_setRefLvalue;
|
||
}
|
||
|
||
// Nodes that change LValue state
|
||
virtual void visit(AstSel* nodep) {
|
||
bool last_setRefLvalue = m_setRefLvalue;
|
||
{
|
||
iterateAndNextNull(nodep->lhsp());
|
||
// Only set lvalues on the from
|
||
m_setRefLvalue = false;
|
||
iterateAndNextNull(nodep->rhsp());
|
||
iterateAndNextNull(nodep->thsp());
|
||
}
|
||
m_setRefLvalue = last_setRefLvalue;
|
||
}
|
||
virtual void visit(AstNodeSel* nodep) {
|
||
bool last_setRefLvalue = m_setRefLvalue;
|
||
{ // Only set lvalues on the from
|
||
iterateAndNextNull(nodep->lhsp());
|
||
m_setRefLvalue = false;
|
||
iterateAndNextNull(nodep->rhsp());
|
||
}
|
||
m_setRefLvalue = last_setRefLvalue;
|
||
}
|
||
virtual void visit(AstCellArrayRef* nodep) {
|
||
bool last_setRefLvalue = m_setRefLvalue;
|
||
{ // selp is not an lvalue
|
||
m_setRefLvalue = false;
|
||
iterateAndNextNull(nodep->selp());
|
||
}
|
||
m_setRefLvalue = last_setRefLvalue;
|
||
}
|
||
virtual void visit(AstNodePreSel* nodep) {
|
||
bool last_setRefLvalue = m_setRefLvalue;
|
||
{ // Only set lvalues on the from
|
||
iterateAndNextNull(nodep->lhsp());
|
||
m_setRefLvalue = false;
|
||
iterateAndNextNull(nodep->rhsp());
|
||
iterateAndNextNull(nodep->thsp());
|
||
}
|
||
m_setRefLvalue = last_setRefLvalue;
|
||
}
|
||
virtual void visit(AstNodeFTask* nodep) {
|
||
m_ftaskp = nodep;
|
||
iterateChildren(nodep);
|
||
m_ftaskp = NULL;
|
||
}
|
||
virtual void visit(AstNodeFTaskRef* nodep) {
|
||
AstNode* pinp = nodep->pinsp();
|
||
AstNodeFTask* taskp = nodep->taskp();
|
||
// We'll deal with mismatching pins later
|
||
if (!taskp) return;
|
||
for (AstNode* stmtp = taskp->stmtsp(); stmtp && pinp; stmtp=stmtp->nextp()) {
|
||
if (const AstVar* portp = VN_CAST(stmtp, Var)) {
|
||
if (portp->isIO()) {
|
||
if (portp->isWritable()) {
|
||
m_setRefLvalue = true;
|
||
iterate(pinp);
|
||
m_setRefLvalue = false;
|
||
} else {
|
||
iterate(pinp);
|
||
}
|
||
// Advance pin
|
||
pinp = pinp->nextp();
|
||
}
|
||
}
|
||
}
|
||
}
|
||
|
||
virtual void visit(AstNode* nodep) {
|
||
// Default: Just iterate
|
||
iterateChildren(nodep);
|
||
}
|
||
|
||
public:
|
||
// CONSTRUCTORS
|
||
LinkLValueVisitor(AstNode* nodep, bool start) {
|
||
m_setRefLvalue = start;
|
||
m_ftaskp = NULL;
|
||
iterate(nodep);
|
||
}
|
||
virtual ~LinkLValueVisitor() {}
|
||
};
|
||
|
||
//######################################################################
|
||
// Link class functions
|
||
|
||
void V3LinkLValue::linkLValue(AstNetlist* nodep) {
|
||
UINFO(4,__FUNCTION__<<": "<<endl);
|
||
{
|
||
LinkLValueVisitor visitor(nodep, false);
|
||
} // Destruct before checking
|
||
V3Global::dumpCheckGlobalTree("linklvalue", 0, v3Global.opt.dumpTreeLevel(__FILE__) >= 6);
|
||
}
|
||
void V3LinkLValue::linkLValueSet(AstNode* nodep) {
|
||
// Called by later link functions when it is known a node needs
|
||
// to be converted to a lvalue.
|
||
UINFO(9,__FUNCTION__<<": "<<endl);
|
||
LinkLValueVisitor visitor(nodep, true);
|
||
}
|