Add links to the graphviz dot graphs xlscc creates.

xls/contrib/xlscc/BUILD

@@ -236,6 +236,7 @@ cc_library(
         "//xls/common/status:ret_check",
         "//xls/common/status:status_macros",
         "//xls/data_structures:leaf_type_tree",
+        "//xls/dev_tools:link_to_source",
         "//xls/interpreter:ir_interpreter",
         "//xls/ir",
         "//xls/ir:bits",
@@ -257,7 +258,6 @@ cc_library(
         "//xls/passes:inlining_pass",
         "//xls/passes:node_source_analysis",
         "//xls/passes:optimization_pass",
-        "//xls/passes:optimization_pass_pipeline",
         "//xls/passes:partial_info_query_engine",
         "//xls/passes:pass_base",
         "//xls/solvers:z3_ir_translator",

xls/contrib/xlscc/continuations.cc

@@ -48,6 +48,7 @@
 #include "xls/contrib/xlscc/translator_types.h"
 #include "xls/contrib/xlscc/xlscc_logging.h"
 #include "xls/data_structures/leaf_type_tree.h"
+#include "xls/dev_tools/link_to_source.h"
 #include "xls/ir/bits.h"
 #include "xls/ir/function_builder.h"
 #include "xls/ir/nodes.h"
@@ -2466,7 +2467,21 @@ absl::Status Translator::MarkDirectIns(GeneratedFunction& func,
   return absl::OkStatus();
 }
 
-std::string Debug_GenerateSliceGraph(const GeneratedFunction& func) {
+namespace {
+std::string LinkifyLocation(const IOOp* op, const xls::Package* package) {
+  if (!op || op->op_location.locations.empty() || package == nullptr) {
+    return "";
+  }
+  auto link = LinkToSource(op->op_location.locations.back(), package);
+  if (!link) {
+    return "";
+  }
+  return absl::StrFormat("href=\"%s\"", *link);
+}
+}  // namespace
+
+std::string Debug_GenerateSliceGraph(const GeneratedFunction& func,
+                                     const xls::Package* package) {
   const bool show_choose_in_states = false;
   const bool show_input_debug_info = false;
 
@@ -2513,27 +2528,32 @@ std::string Debug_GenerateSliceGraph(const GeneratedFunction& func) {
       }
     }
 
+    const std::string rank_full_name =
+        GraphvizEscape(absl::StrFormat("%p_rank", &slice));
     const std::string rank_input_name =
-        GraphvizEscape(absl::StrFormat("%p_inputs", &slice));
+        absl::StrFormat("%s:input", rank_full_name);
     const std::string rank_output_name =
-        GraphvizEscape(absl::StrFormat("%p_outputs", &slice));
-
-    rank_orders.push_back(
-        absl::StrFormat("  %s -> %s", rank_input_name, rank_output_name));
+        absl::StrFormat("%s:output", rank_full_name);
+    const std::string link =
+        slice_index != 0 ? LinkifyLocation(slice.after_op, package) : "";
+    const std::string link_label =
+        link.empty()
+            ? ""
+            : absl::StrFormat(" [line:%d] [link]",
+                              slice.after_op->op_location.locations.back()
+                                  .lineno()
+                                  .value());
+    const std::string rank_label = absl::StrFormat(
+        "{ <input> inputs | <id> [%d] %s%s | "
+        "<output> outputs }",
+        slice_index, new_rank, link_label);
+    node_names.push_back(absl::StrFormat("  %s [shape=record label=\"%s\" %s];",
+                                         rank_full_name, rank_label, link));
     if (!last_rank_name.empty()) {
       rank_orders.push_back(
           absl::StrFormat("  %s -> %s", last_rank_name, rank_input_name));
     }
 
-    node_names.push_back(
-        absl::StrFormat("  %s [label=%s style=rounded];", rank_input_name,
-                        GraphvizEscape(absl::StrFormat(
-                            "[%i] %s inputs", slice_index, new_rank))));
-    node_names.push_back(
-        absl::StrFormat("  %s [label=%s];", rank_output_name,
-                        GraphvizEscape(absl::StrFormat(
-                            "[%i] %s outputs", slice_index, new_rank))));
-
     last_rank_name = rank_output_name;
 
     std::vector<std::string> nodes_in_input_rank = {rank_input_name};

xls/contrib/xlscc/main.cc

@@ -282,16 +282,17 @@ static absl::Status Run(std::string_view cpp_path) {
   std::filesystem::path debug_write_function_slice_graph_path(
       absl::GetFlag(FLAGS_debug_write_function_slice_graph_path));
 
-  auto write_to_output =
-      [&](std::string_view output,
-          const GeneratedFunction* top_function) -> absl::Status {
+  auto write_to_output = [&](std::string_view output,
+                             const GeneratedFunction* top_function,
+                             const xls::Package* package) -> absl::Status {
     if (output_file.empty()) {
       std::cout << output;
     } else {
       XLS_RETURN_IF_ERROR(xls::SetFileContents(output_file, output));
     }
     if (!debug_write_function_slice_graph_path.empty()) {
-      const std::string graph = Debug_GenerateSliceGraph(*top_function);
+      const std::string graph =
+          Debug_GenerateSliceGraph(*top_function, package);
       XLS_RETURN_IF_ERROR(
           xls::SetFileContents(debug_write_function_slice_graph_path, graph));
     }
@@ -311,8 +312,8 @@ static absl::Status Run(std::string_view cpp_path) {
     translator.AddSourceInfoToPackage(package);
 
     std::cerr << "Saving Package IR..." << '\n';
-    XLS_RETURN_IF_ERROR(
-        write_to_output(absl::StrCat(package.DumpIr(), "\n"), top_function));
+    XLS_RETURN_IF_ERROR(write_to_output(absl::StrCat(package.DumpIr(), "\n"),
+                                        top_function, &package));
   } else {
     xls::Proc* proc = nullptr;
 
@@ -342,8 +343,8 @@ static absl::Status Run(std::string_view cpp_path) {
     const GeneratedFunction* top_function =
         translator.GetGeneratedFunction(top_function_decl);
 
-    XLS_RETURN_IF_ERROR(
-        write_to_output(absl::StrCat(package.DumpIr(), "\n"), top_function));
+    XLS_RETURN_IF_ERROR(write_to_output(absl::StrCat(package.DumpIr(), "\n"),
+                                        top_function, &package));
   }
 
   const std::string metadata_out_path = absl::GetFlag(FLAGS_meta_out);

xls/contrib/xlscc/translator.h

@@ -85,7 +85,8 @@ class Translator;
 class NewFSMGenerator;
 
 std::string Debug_GenerateReadableTypeName(xls::Type* type);
-std::string Debug_GenerateSliceGraph(const GeneratedFunction& func);
+std::string Debug_GenerateSliceGraph(const GeneratedFunction& func,
+                                     const xls::Package* package);
 
 struct TranslationContext;
 

xls/contrib/xlscc/unit_tests/continuations_test.cc

@@ -76,8 +76,8 @@ class ContinuationsTest : public XlsccTestBase {
     LOG(INFO) << package_->DumpIr();
 
     LogContinuations(*func);
-    testing::Test::RecordProperty("GraphViz file",
-                                  Debug_GenerateSliceGraph(*func));
+    testing::Test::RecordProperty(
+        "GraphViz file", Debug_GenerateSliceGraph(*func, package_.get()));
 
     return func;
   }

xls/contrib/xlscc/unit_tests/unit_test.cc

@@ -387,8 +387,8 @@ absl::StatusOr<std::string> XlsccTestBase::SourceToIr(
                          translator_->GenerateIR_Top_Function(
                              package_.get(), top_channel_injections));
 
-    testing::Test::RecordProperty("GraphViz file",
-                                  Debug_GenerateSliceGraph(*func));
+    testing::Test::RecordProperty(
+        "GraphViz file", Debug_GenerateSliceGraph(*func, package_.get()));
 
     XLS_RETURN_IF_ERROR(package_->SetTopByName(func->xls_func->name()));
     if (pfunc != nullptr) {
@@ -484,8 +484,8 @@ void XlsccTestBase::BuildTestIR(
   const xlscc::GeneratedFunction* top_func =
       translator_->GetGeneratedFunction(top_decl);
 
-  testing::Test::RecordProperty("GraphViz file",
-                                Debug_GenerateSliceGraph(*top_func));
+  testing::Test::RecordProperty(
+      "GraphViz file", Debug_GenerateSliceGraph(*top_func, package_.get()));
 
   for (const xlscc::HLSChannel& ch : block_spec_.channels()) {
     if (ch.type() == xlscc::CHANNEL_TYPE_DIRECT_IN) {
@@ -1022,8 +1022,8 @@ void XlsccTestBase::IOTest(std::string_view content, std::list<IOOpTest> inputs,
   const xlscc::GeneratedFunction* top_func =
       translator_->GetGeneratedFunction(top_decl);
 
-  testing::Test::RecordProperty("GraphViz file",
-                                Debug_GenerateSliceGraph(*top_func));
+  testing::Test::RecordProperty(
+      "GraphViz file", Debug_GenerateSliceGraph(*top_func, package_.get()));
 
   XLS_ASSERT_OK_AND_ASSIGN(package_, ParsePackage(ir_src));
 

xls/dev_tools/BUILD

@@ -976,3 +976,16 @@ pytype_strict_contrib_test(
         "@abseil-py//absl/testing:absltest",
     ],
 )
+
+cc_library(
+    name = "link_to_source",
+    srcs = [
+        "link_to_source.cc",
+    ],
+    hdrs = ["link_to_source.h"],
+    deps = [
+        "//xls/ir",
+        "//xls/ir:source_location",
+        "@com_google_absl//absl/strings:str_format",
+    ],
+)

xls/dev_tools/link_to_source.cc

@@ -0,0 +1,35 @@
+// Copyright 2026 The XLS Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "xls/dev_tools/link_to_source.h"
+
+#include <optional>
+#include <string>
+
+#include "absl/strings/str_format.h"
+#include "xls/ir/package.h"
+#include "xls/ir/source_location.h"
+
+namespace xls {
+
+std::optional<std::string> LinkToSource(const SourceLocation& loc,
+                                        const Package* package) {
+  auto it = package->fileno_to_name().find(loc.fileno());
+  if (it == package->fileno_to_name().end()) {
+    return std::nullopt;
+  }
+  return absl::StrFormat("file://%s", it->second);
+}
+
+}  // namespace xls

xls/dev_tools/link_to_source.h

@@ -0,0 +1,34 @@
+// Copyright 2026 The XLS Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef XLS_DEV_TOOLS_LINK_TO_SOURCE_H_
+#define XLS_DEV_TOOLS_LINK_TO_SOURCE_H_
+
+#include <optional>
+#include <string>
+
+#include "xls/ir/package.h"
+#include "xls/ir/source_location.h"
+
+namespace xls {
+
+// Get a link to the source code associated with the given source location.
+//
+// TODO(allight): Let the link format be configurable with a flag.
+std::optional<std::string> LinkToSource(const SourceLocation& loc,
+                                        const Package* package);
+
+}  // namespace xls
+
+#endif  // XLS_DEV_TOOLS_LINK_TO_SOURCE_H_