luke/verilator
1
0
Fork 0
mirror of https://github.com/verilator/verilator.git synced 2026-10-06 10:03:44 +02:00
Code Issues Packages Projects Releases Wiki Activity

Improve Dfg type system (#6390)

Browse Source 
Added a mini type system for Dfg using DfgDataType to replace Dfg's use
of AstNodeDType. This is much more restricted and represents only the
types Dfg can handle in a canonical form. This will be needed when
adding more support for unpacked arrays and maybe unpacked structs one
day.

Also added an internal type checker for DfgGraphs which encodes all the
assumptions the code makes about type relationships in the graph. Run
this in a few places with --debug-check. Fix resulting fallout.
This commit is contained in:
Geza Lore
2025-09-07 20:38:50 +01:00
committed by GitHub
parent f67534069c
commit 6bc48fcdb3
27 changed files with 778 additions and 394 deletions
Download Patch File Download Diff File Expand all files Collapse all files
src/V3Dfg.cpp
+16 -44
View File
@@ -23,34 +23,6 @@
VL_DEFINE_DEBUG_FUNCTIONS;
//------------------------------------------------------------------------------
// V3Dfg
// predicate for supported data types
static bool dfgGraphIsSupportedDTypePacked(const AstNodeDType* dtypep) {
dtypep = dtypep->skipRefp();
if (const AstBasicDType* const typep = VN_CAST(dtypep, BasicDType)) {
return typep->keyword().isIntNumeric();
}
if (const AstPackArrayDType* const typep = VN_CAST(dtypep, PackArrayDType)) {
return dfgGraphIsSupportedDTypePacked(typep->subDTypep());
}
if (const AstNodeUOrStructDType* const typep = VN_CAST(dtypep, NodeUOrStructDType)) {
return typep->packed();
}
return false;
}
bool V3Dfg::isSupported(const AstNodeDType* dtypep) {
dtypep = dtypep->skipRefp();
// Support 1 dimensional unpacked arrays of packed types
if (const AstUnpackArrayDType* const typep = VN_CAST(dtypep, UnpackArrayDType)) {
return dfgGraphIsSupportedDTypePacked(typep->subDTypep());
}
// Support packed types
return dfgGraphIsSupportedDTypePacked(dtypep);
}
//------------------------------------------------------------------------------
// DfgGraph
@@ -113,28 +85,28 @@ std::unique_ptr<DfgGraph> DfgGraph::clone() const {
switch (vtx.type()) {
#include "V3Dfg__gen_clone_cases.h" // From ./astgen
case VDfgType::Sel: {
DfgSel* const cp = new DfgSel{*clonep, vtx.fileline(), vtx.dtypep()};
DfgSel* const cp = new DfgSel{*clonep, vtx.fileline(), vtx.dtype()};
cp->lsb(vtx.as<DfgSel>()->lsb());
vtxp2clonep.emplace(&vtx, cp);
break;
}
case VDfgType::UnitArray: {
DfgUnitArray* const cp = new DfgUnitArray{*clonep, vtx.fileline(), vtx.dtypep()};
DfgUnitArray* const cp = new DfgUnitArray{*clonep, vtx.fileline(), vtx.dtype()};
vtxp2clonep.emplace(&vtx, cp);
break;
}
case VDfgType::Mux: {
DfgMux* const cp = new DfgMux{*clonep, vtx.fileline(), vtx.dtypep()};
DfgMux* const cp = new DfgMux{*clonep, vtx.fileline(), vtx.dtype()};
vtxp2clonep.emplace(&vtx, cp);
break;
}
case VDfgType::SpliceArray: {
DfgSpliceArray* const cp = new DfgSpliceArray{*clonep, vtx.fileline(), vtx.dtypep()};
DfgSpliceArray* const cp = new DfgSpliceArray{*clonep, vtx.fileline(), vtx.dtype()};
vtxp2clonep.emplace(&vtx, cp);
break;
}
case VDfgType::SplicePacked: {
DfgSplicePacked* const cp = new DfgSplicePacked{*clonep, vtx.fileline(), vtx.dtypep()};
DfgSplicePacked* const cp = new DfgSplicePacked{*clonep, vtx.fileline(), vtx.dtype()};
vtxp2clonep.emplace(&vtx, cp);
break;
}
@@ -265,13 +237,13 @@ std::string DfgGraph::makeUniqueName(const std::string& prefix, size_t n) {
return "__Vdfg" + prefix + m_tmpNameStub + std::to_string(n);
}
DfgVertexVar* DfgGraph::makeNewVar(FileLine* flp, const std::string& name, AstNodeDType* dtypep,
AstScope* scopep) {
DfgVertexVar* DfgGraph::makeNewVar(FileLine* flp, const std::string& name,
const DfgDataType& dtype, AstScope* scopep) {
UASSERT_OBJ(!!scopep != !!modulep(), flp,
"makeNewVar scopep should only be provided for a scoped DfgGraph");
// Create AstVar
AstVar* const varp = new AstVar{flp, VVarType::MODULETEMP, name, dtypep};
AstVar* const varp = new AstVar{flp, VVarType::MODULETEMP, name, dtype.astDtypep()};
if (scopep) {
// Add AstVar to the scope's module
@@ -281,13 +253,13 @@ DfgVertexVar* DfgGraph::makeNewVar(FileLine* flp, const std::string& name, AstNo
// Add to scope
scopep->addVarsp(vscp);
// Create and return the corresponding variable vertex
if (VN_IS(varp->dtypeSkipRefp(), UnpackArrayDType)) return new DfgVarArray{*this, vscp};
if (dtype.isArray()) return new DfgVarArray{*this, vscp};
return new DfgVarPacked{*this, vscp};
} else {
// Add AstVar to containing module
modulep()->addStmtsp(varp);
// Create and return the corresponding variable vertex
if (VN_IS(varp->dtypeSkipRefp(), UnpackArrayDType)) return new DfgVarArray{*this, varp};
if (dtype.isArray()) return new DfgVarArray{*this, varp};
return new DfgVarPacked{*this, varp};
}
}
@@ -314,7 +286,7 @@ static void dumpDotVertex(std::ostream& os, const DfgVertex& vtx) {
}
// Type and fanout
os << '\n';
varVtxp->dtypep()->dumpSmall(os);
varVtxp->dtype().astDtypep()->dumpSmall(os);
os << " / F" << varVtxp->fanout();
// End 'label'
os << '"';
@@ -371,7 +343,7 @@ static void dumpDotVertex(std::ostream& os, const DfgVertex& vtx) {
os << toDotId(vtx);
os << " [label=\"SEL _[" << msb << ":" << lsb << "]\n";
os << cvtToHex(selVtxp) << '\n';
vtx.dtypep()->dumpSmall(os);
vtx.dtype().astDtypep()->dumpSmall(os);
os << " / F" << vtx.fanout() << '"';
if (vtx.hasMultipleSinks()) {
os << ", shape=doublecircle";
@@ -386,7 +358,7 @@ static void dumpDotVertex(std::ostream& os, const DfgVertex& vtx) {
os << toDotId(vtx);
os << " [label=\"" << vtx.typeName() << '\n';
os << cvtToHex(&vtx) << '\n';
vtx.dtypep()->dumpSmall(os);
vtx.dtype().astDtypep()->dumpSmall(os);
os << " / F" << vtx.fanout() << '"';
if (vtx.hasMultipleSinks()) {
os << ", shape=doubleoctagon";
@@ -423,7 +395,7 @@ static void dumpDotVertex(std::ostream& os, const DfgVertex& vtx) {
os << toDotId(vtx);
os << " [label=\"" << vtx.typeName() << '\n';
os << cvtToHex(&vtx) << '\n';
vtx.dtypep()->dumpSmall(os);
vtx.dtype().astDtypep()->dumpSmall(os);
os << " / F" << vtx.fanout() << '"';
if (vtx.hasMultipleSinks()) {
os << ", shape=doublecircle";
@@ -554,9 +526,9 @@ DfgGraph::sinkCone(const std::vector<const DfgVertex*>& vtxps) const {
//------------------------------------------------------------------------------
// DfgVertex
DfgVertex::DfgVertex(DfgGraph& dfg, VDfgType type, FileLine* flp, AstNodeDType* dtypep)
DfgVertex::DfgVertex(DfgGraph& dfg, VDfgType type, FileLine* flp, const DfgDataType& dt)
: m_filelinep{flp}
, m_dtypep{dtypep}
, m_dtype{dt}
, m_type{type} {
dfg.addVertex(*this);
}