[ImportVerilog]Dedup module Op (#7245)

Co-authored-by: Fabian Schuiki <fabian@schuiki.ch>

lib/Conversion/ImportVerilog/ImportVerilogInternals.h

@@ -36,6 +36,8 @@ struct PortLowering {
 struct ModuleLowering {
   moore::SVModuleOp op;
   SmallVector<PortLowering> ports;
+  DenseMap<const slang::syntax::SyntaxNode *, const slang::ast::PortSymbol *>
+      portsBySyntaxNode;
 };
 
 /// A helper class to facilitate the conversion from a Slang AST to MLIR

lib/Conversion/ImportVerilog/Structure.cpp

@@ -133,6 +133,10 @@ struct MemberVisitor {
       // connection for the port.
       if (!expr) {
         auto *port = con->port.as_if<PortSymbol>();
+        if (auto *existingPort =
+                moduleLowering->portsBySyntaxNode.lookup(port->getSyntax()))
+          port = existingPort;
+
         switch (port->direction) {
         case slang::ast::ArgumentDirection::In: {
           auto refType = moore::RefType::get(
@@ -191,6 +195,9 @@ struct MemberVisitor {
                          : context.convertLvalueExpression(*expr);
         if (!value)
           return failure();
+        if (auto *existingPort =
+                moduleLowering->portsBySyntaxNode.lookup(con->port.getSyntax()))
+          port = existingPort;
         portValues.insert({port, value});
         continue;
       }
@@ -206,6 +213,9 @@ struct MemberVisitor {
         unsigned offset = 0;
         auto i32 = moore::IntType::getInt(context.getContext(), 32);
         for (const auto *port : llvm::reverse(multiPort->ports)) {
+          if (auto *existingPort = moduleLowering->portsBySyntaxNode.lookup(
+                  con->port.getSyntax()))
+            port = existingPort;
           unsigned width = port->getType().getBitWidth();
           auto index = builder.create<moore::ConstantOp>(loc, i32, offset);
           auto sliceType = context.convertType(port->getType());
@@ -470,7 +480,56 @@ ModuleLowering *
 Context::convertModuleHeader(const slang::ast::InstanceBodySymbol *module) {
   using slang::ast::ArgumentDirection;
   using slang::ast::MultiPortSymbol;
+  using slang::ast::ParameterSymbol;
   using slang::ast::PortSymbol;
+  using slang::ast::TypeParameterSymbol;
+
+  auto parameters = module->parameters;
+  bool hasModuleSame = false;
+  // If there is already exist a module that has the same name with this
+  // module ,has the same parent scope and has the same parameters we can
+  // define this module is a duplicate module
+  for (auto const &existingModule : modules) {
+    if (module->getDeclaringDefinition() ==
+        existingModule.getFirst()->getDeclaringDefinition()) {
+      auto moduleParameters = existingModule.getFirst()->parameters;
+      hasModuleSame = true;
+      for (auto it1 = parameters.begin(), it2 = moduleParameters.begin();
+           it1 != parameters.end() && it2 != moduleParameters.end();
+           it1++, it2++) {
+        // Parameters size different
+        if (it1 == parameters.end() || it2 == moduleParameters.end()) {
+          hasModuleSame = false;
+          break;
+        }
+        const auto *para1 = (*it1)->symbol.as_if<ParameterSymbol>();
+        const auto *para2 = (*it2)->symbol.as_if<ParameterSymbol>();
+        // Parameters kind different
+        if ((para1 == nullptr) ^ (para2 == nullptr)) {
+          hasModuleSame = false;
+          break;
+        }
+        // Compare ParameterSymbol
+        if (para1 != nullptr) {
+          hasModuleSame = para1->getValue() == para2->getValue();
+        }
+        // Compare TypeParameterSymbol
+        if (para1 == nullptr) {
+          auto para1Type = convertType(
+              (*it1)->symbol.as<TypeParameterSymbol>().getTypeAlias());
+          auto para2Type = convertType(
+              (*it2)->symbol.as<TypeParameterSymbol>().getTypeAlias());
+          hasModuleSame = para1Type == para2Type;
+        }
+        if (!hasModuleSame)
+          break;
+      }
+      if (hasModuleSame) {
+        module = existingModule.first;
+        break;
+      }
+    }
+  }
 
   auto &slot = modules[module];
   if (slot)
@@ -553,6 +612,11 @@ Context::convertModuleHeader(const slang::ast::InstanceBodySymbol *module) {
 
   // Schedule the body to be lowered.
   moduleWorklist.push(module);
+
+  // Map duplicate port by Syntax
+  for (const auto &port : lowering.ports)
+    lowering.portsBySyntaxNode.insert({port.ast.getSyntax(), &port.ast});
+
   return &lowering;
 }
 

test/Conversion/ImportVerilog/basic.sv

@@ -20,6 +20,38 @@ module Empty;
   ; // empty member
 endmodule
 
+
+module DedupA(input wire a,
+input wire b,
+output wire [3:0] c);
+endmodule
+
+module DedupB #(parameter p = 32)
+(input wire a,
+input wire b,
+output wire [3:0] c);
+endmodule
+
+// CHECK-LABEL: moore.module private @DedupA(in %a : !moore.l1, in %b : !moore.l1, out c : !moore.l4) {
+// CHECK-LABEL: moore.module private @DedupB(in %a : !moore.l1, in %b : !moore.l1, out c : !moore.l4) {
+// CHECK-LABEL: moore.module private @DedupB_0(in %a : !moore.l1, in %b : !moore.l1, out c : !moore.l4) {
+// CHECK-LABEL: moore.module @Dedup
+module Dedup;
+  wire [3:0] a;
+  wire [3:0] b;
+  wire [3:0] c;
+  // CHECK-LABEL: moore.instance "insA" @DedupA
+  DedupA insA(.a(a), .c(c));
+  // CHECK-LABEL: moore.instance "insB" @DedupA
+  DedupA insB(.b(b), .c(c));
+  // CHECK-LABEL: moore.instance "insC" @DedupB
+  DedupB insC(.c(c));
+  // CHECK-LABEL: moore.instance "insD" @DedupB
+  DedupB insD(.a(a), .b(b), .c(c));
+  // CHECK-LABEL: moore.instance "insE" @DedupB_0
+  DedupB #(8) insE(.c(c));
+endmodule
+
 // CHECK-LABEL: moore.module @NestedA() {
 // CHECK:         moore.instance "NestedB" @NestedB
 // CHECK:       }