forked from github/verilator
536bdf506e
Verilator should now correctly re-evaluate any logic that depends on state set in a DPI exported function, including if the DPI export is called outside eval, or if the DPI export is called from a DPI import. Whenever the design contains a DPI exported function that sets a non-local variable, we create a global __Vdpi_export_trigger flag, that is set in the body of the DPI export, and make all variables set in any DPI exported functions dependent on this flag (this ensures correct ordering and change detection on state set in DPI exports when needed). The DPI export trigger flag is cleared at the end of eval, which ensured calls to DPI exports outside of eval are detected. Additionally the ordering is modifies to assume that any call to a 'context' DPI import might call DPI exports by adding an edge to the ordering graph from the logic vertex containing the call to the DPI import to the DPI export trigger variable vertex (note the standard does not allow calls to DPI exports from DPI imports that were not imported with 'context', so we do not enforce ordering on those).
241 lines
9.2 KiB
C++
241 lines
9.2 KiB
C++
// -*- mode: C++; c-file-style: "cc-mode" -*-
|
|
//*************************************************************************
|
|
// DESCRIPTION: Verilator: Generated Clock repairs
|
|
//
|
|
// Code available from: https://verilator.org
|
|
//
|
|
//*************************************************************************
|
|
//
|
|
// Copyright 2003-2021 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.
|
|
// SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
|
|
//
|
|
//*************************************************************************
|
|
// GENCLK TRANSFORMATIONS:
|
|
// Follow control-flow graph with assignments and var usages
|
|
// ASSIGNDLY to variable later used as clock requires change detect
|
|
//
|
|
//*************************************************************************
|
|
|
|
#include "config_build.h"
|
|
#include "verilatedos.h"
|
|
|
|
#include "V3Global.h"
|
|
#include "V3GenClk.h"
|
|
#include "V3Ast.h"
|
|
|
|
//######################################################################
|
|
// GenClk state, as a visitor of each AstNode
|
|
|
|
class GenClkBaseVisitor VL_NOT_FINAL : public AstNVisitor {
|
|
protected:
|
|
VL_DEBUG_FUNC; // Declare debug()
|
|
};
|
|
|
|
//######################################################################
|
|
// GenClk Read
|
|
|
|
class GenClkRenameVisitor final : public GenClkBaseVisitor {
|
|
private:
|
|
// NODE STATE
|
|
// Cleared on top scope
|
|
// AstVarScope::user2() -> AstVarScope*. Signal replacing activation with
|
|
// AstVarRef::user3() -> bool. Signal is replaced activation (already done)
|
|
AstUser2InUse m_inuser2;
|
|
AstUser3InUse m_inuser3;
|
|
|
|
// STATE
|
|
AstActive* m_activep = nullptr; // Inside activate statement
|
|
AstNodeModule* m_topModp; // Top module
|
|
AstScope* m_scopetopp = nullptr; // Scope under TOPSCOPE
|
|
|
|
// METHODS
|
|
AstVarScope* genInpClk(AstVarScope* vscp) {
|
|
if (vscp->user2p()) {
|
|
return VN_CAST(vscp->user2p(), VarScope);
|
|
} else {
|
|
// In order to create a __VinpClk* for a signal, it needs to be marked circular.
|
|
// The DPI export trigger is never marked circular by V3Order (see comments in
|
|
// OrderVisitor::nodeMarkCircular). The only other place where one might mark
|
|
// a node circular is in this pass (V3GenClk), if the signal is assigned but was
|
|
// previously used as a clock. The DPI export trigger is only ever assigned in
|
|
// a DPI export called from outside eval, or from a DPI import, which are not
|
|
// discovered by GenClkReadVisitor (note that impure tasks - i.e.: those setting
|
|
// non-local variables - cannot be no-inline, see V3Task), hence the DPI export
|
|
// trigger should never be marked circular. Note that ordering should still be
|
|
// correct as there will be a change detect on any signals set from a DPI export
|
|
// that might have dependents scheduled earlier.
|
|
UASSERT_OBJ(vscp != v3Global.rootp()->dpiExportTriggerp(), vscp,
|
|
"DPI export trigger should not need __VinpClk");
|
|
AstVar* varp = vscp->varp();
|
|
string newvarname
|
|
= "__VinpClk__" + vscp->scopep()->nameDotless() + "__" + varp->name();
|
|
// Create: VARREF(inpclk)
|
|
// ...
|
|
// ASSIGN(VARREF(inpclk), VARREF(var))
|
|
AstVar* newvarp
|
|
= new AstVar(varp->fileline(), AstVarType::MODULETEMP, newvarname, varp);
|
|
m_topModp->addStmtp(newvarp);
|
|
AstVarScope* newvscp = new AstVarScope(vscp->fileline(), m_scopetopp, newvarp);
|
|
m_scopetopp->addVarp(newvscp);
|
|
AstAssign* asninitp = new AstAssign(
|
|
vscp->fileline(), new AstVarRef(vscp->fileline(), newvscp, VAccess::WRITE),
|
|
new AstVarRef(vscp->fileline(), vscp, VAccess::READ));
|
|
m_scopetopp->addFinalClkp(asninitp);
|
|
//
|
|
vscp->user2p(newvscp);
|
|
return newvscp;
|
|
}
|
|
}
|
|
|
|
// VISITORS
|
|
virtual void visit(AstTopScope* nodep) override {
|
|
AstNode::user2ClearTree(); // user2p() used on entire tree
|
|
|
|
AstScope* scopep = nodep->scopep();
|
|
UASSERT_OBJ(scopep, nodep, "No scope found on top level");
|
|
m_scopetopp = scopep;
|
|
|
|
iterateChildren(nodep);
|
|
}
|
|
//----
|
|
virtual void visit(AstVarRef* nodep) override {
|
|
// Consumption/generation of a variable,
|
|
AstVarScope* vscp = nodep->varScopep();
|
|
UASSERT_OBJ(vscp, nodep, "Scope not assigned");
|
|
if (m_activep && !nodep->user3()) {
|
|
nodep->user3(true);
|
|
if (vscp->isCircular()) {
|
|
UINFO(8, " VarActReplace " << nodep << endl);
|
|
// Replace with the new variable
|
|
AstVarScope* newvscp = genInpClk(vscp);
|
|
AstVarRef* newrefp = new AstVarRef(nodep->fileline(), newvscp, nodep->access());
|
|
nodep->replaceWith(newrefp);
|
|
VL_DO_DANGLING(pushDeletep(nodep), nodep);
|
|
}
|
|
}
|
|
}
|
|
virtual void visit(AstActive* nodep) override {
|
|
m_activep = nodep;
|
|
UASSERT_OBJ(nodep->sensesp(), nodep, "Unlinked");
|
|
iterateChildren(nodep->sensesp()); // iterateAndNext?
|
|
m_activep = nullptr;
|
|
iterateChildren(nodep);
|
|
}
|
|
|
|
//-----
|
|
virtual void visit(AstNode* nodep) override { iterateChildren(nodep); }
|
|
|
|
public:
|
|
// CONSTRUCTORS
|
|
GenClkRenameVisitor(AstTopScope* nodep, AstNodeModule* topModp)
|
|
: m_topModp{topModp} {
|
|
iterate(nodep);
|
|
}
|
|
virtual ~GenClkRenameVisitor() override = default;
|
|
};
|
|
|
|
//######################################################################
|
|
// GenClk Read
|
|
|
|
class GenClkReadVisitor final : public GenClkBaseVisitor {
|
|
private:
|
|
// NODE STATE
|
|
// Cleared on top scope
|
|
// AstVarScope::user() -> bool. Set when the var has been used as clock
|
|
AstUser1InUse m_inuser1;
|
|
|
|
// STATE
|
|
bool m_tracingCall = false; // Iterating into a call to a cfunc
|
|
AstActive* m_activep = nullptr; // Inside activate statement
|
|
AstNodeAssign* m_assignp = nullptr; // Inside assigndly statement
|
|
AstNodeModule* m_topModp = nullptr; // Top module
|
|
|
|
// VISITORS
|
|
virtual void visit(AstTopScope* nodep) override {
|
|
AstNode::user1ClearTree(); // user1p() used on entire tree
|
|
iterateChildren(nodep);
|
|
{
|
|
// Make the new clock signals and replace any activate references
|
|
// See rename, it does some AstNode::userClearTree()'s
|
|
GenClkRenameVisitor visitor{nodep, m_topModp};
|
|
}
|
|
}
|
|
virtual void visit(AstNodeModule* nodep) override {
|
|
// Only track the top scopes, not lower level functions
|
|
if (nodep->isTop()) {
|
|
m_topModp = nodep;
|
|
iterateChildren(nodep);
|
|
}
|
|
}
|
|
virtual void visit(AstNodeCCall* nodep) override {
|
|
iterateChildren(nodep);
|
|
if (!nodep->funcp()->entryPoint()) {
|
|
// Enter the function and trace it
|
|
m_tracingCall = true;
|
|
iterate(nodep->funcp());
|
|
}
|
|
}
|
|
virtual void visit(AstCFunc* nodep) override {
|
|
if (!m_tracingCall && !nodep->entryPoint()) {
|
|
// Only consider logic within a CFunc when looking
|
|
// at the call to it, and not when scanning whatever
|
|
// scope it happens to live beneath.
|
|
return;
|
|
}
|
|
m_tracingCall = false;
|
|
iterateChildren(nodep);
|
|
}
|
|
//----
|
|
|
|
virtual void visit(AstVarRef* nodep) override {
|
|
// Consumption/generation of a variable,
|
|
AstVarScope* vscp = nodep->varScopep();
|
|
UASSERT_OBJ(vscp, nodep, "Scope not assigned");
|
|
if (m_activep) {
|
|
UINFO(8, " VarAct " << nodep << endl);
|
|
vscp->user1(true);
|
|
}
|
|
if (m_assignp && nodep->access().isWriteOrRW() && vscp->user1()) {
|
|
// Variable was previously used as a clock, and is now being set
|
|
// Thus a unordered generated clock...
|
|
UINFO(8, " VarSetAct " << nodep << endl);
|
|
vscp->circular(true);
|
|
}
|
|
}
|
|
virtual void visit(AstNodeAssign* nodep) override {
|
|
// UINFO(8, "ASS " << nodep << endl);
|
|
m_assignp = nodep;
|
|
iterateChildren(nodep);
|
|
m_assignp = nullptr;
|
|
}
|
|
virtual void visit(AstActive* nodep) override {
|
|
UINFO(8, "ACTIVE " << nodep << endl);
|
|
m_activep = nodep;
|
|
UASSERT_OBJ(nodep->sensesp(), nodep, "Unlinked");
|
|
iterateChildren(nodep->sensesp()); // iterateAndNext?
|
|
m_activep = nullptr;
|
|
iterateChildren(nodep);
|
|
}
|
|
|
|
//-----
|
|
virtual void visit(AstVar*) override {} // Don't want varrefs under it
|
|
virtual void visit(AstNode* nodep) override { iterateChildren(nodep); }
|
|
|
|
public:
|
|
// CONSTRUCTORS
|
|
explicit GenClkReadVisitor(AstNetlist* nodep) { iterate(nodep); }
|
|
virtual ~GenClkReadVisitor() override = default;
|
|
};
|
|
|
|
//######################################################################
|
|
// GenClk class functions
|
|
|
|
void V3GenClk::genClkAll(AstNetlist* nodep) {
|
|
UINFO(2, __FUNCTION__ << ": " << endl);
|
|
{ GenClkReadVisitor visitor{nodep}; } // Destruct before checking
|
|
V3Global::dumpCheckGlobalTree("genclk", 0, v3Global.opt.dumpTreeLevel(__FILE__) >= 3);
|
|
}
|