15 #include "mlir/IR/BuiltinOps.h"
16 #include "mlir/IR/Threading.h"
17 #include "llvm/Support/Debug.h"
19 #define DEBUG_TYPE "firrtl-inner-symbol-dce"
22 using namespace circt;
23 using namespace firrtl;
33 assert(InnerSymbolTable::getInnerSymbol(target));
36 auto mod = cast<FModuleLike>(target.
getOp());
38 auto base = mod.getPortSymbolAttr(target.
getPort());
39 cast<firrtl::FModuleLike>(*mod).setPortSymbolsAttr(
44 auto symOp = cast<InnerSymbolOpInterface>(target.
getOp());
45 auto base = symOp.getInnerSymAttr();
46 symOp.setInnerSymbolAttr(base.erase(target.
getField()));
50 void runOnOperation()
override;
53 void findInnerRefs(Attribute attr);
54 void insertInnerRef(InnerRefAttr innerRef);
55 void removeInnerSyms(FModuleLike mod);
57 DenseSet<std::pair<StringAttr, StringAttr>>
innerRefs;
63 attr.walk([&](Attribute subAttr) {
64 if (
auto innerRef = dyn_cast<InnerRefAttr>(subAttr))
65 insertInnerRef(innerRef);
71 StringAttr moduleName = innerRef.getModule();
72 StringAttr symName = innerRef.getName();
77 auto [iter, inserted] = innerRefs.insert({moduleName, symName});
81 LLVM_DEBUG(llvm::dbgs() <<
DEBUG_TYPE <<
": found reference to " << moduleName
82 <<
"::" << symName <<
'\n';);
87 auto moduleName = mod.getModuleNameAttr();
90 InnerSymbolTable::walkSymbols(
92 ++numInnerSymbolsFound;
95 if (innerRefs.contains({moduleName, name}))
99 ++numInnerSymbolsRemoved;
101 LLVM_DEBUG(llvm::dbgs() <<
DEBUG_TYPE <<
": removed " << moduleName
102 <<
"::" << name <<
'\n';);
109 ModuleOp topModule = getOperation();
112 SmallVector<FModuleLike> modules;
113 topModule.walk([&](Operation *op) {
115 for (NamedAttribute namedAttr : op->getAttrs())
116 findInnerRefs(namedAttr.getValue());
119 if (
auto mod = dyn_cast<FModuleLike>(op))
120 modules.push_back(mod);
125 parallelForEach(&getContext(), modules,
126 [&](FModuleLike mod) { removeInnerSyms(mod); });
130 return std::make_unique<InnerSymbolDCEPass>();
assert(baseType &&"element must be base type")
static void dropSymbol(const InnerSymTarget &target)
Drop the specified symbol.
The target of an inner symbol, the entity the symbol is a handle for.
Operation * getOp() const
Return the target's base operation. For ports, this is the module.
auto getField() const
Return the target's fieldID.
auto getPort() const
Return the target's port, if valid. Check "isPort()".
bool isPort() const
Return if this targets a port.
std::unique_ptr< mlir::Pass > createInnerSymbolDCEPass()
The InstanceGraph op interface, see InstanceGraphInterface.td for more details.
void removeInnerSyms(FModuleLike mod)
Remove all dead inner symbols from the specified module.
void findInnerRefs(Attribute attr)
Find all InnerRefAttrs inside a given Attribute.
void runOnOperation() override
void insertInnerRef(InnerRefAttr innerRef)
Add an InnerRefAttr to the set of all InnerRefAttrs.
DenseSet< std::pair< StringAttr, StringAttr > > innerRefs