[WIP] Verible standalone preprocessor

common/util/BUILD

@@ -41,6 +41,16 @@ cc_library(
     deps = ["@com_google_absl//absl/base:core_headers"],
 )
 
+cc_library(
+    name = "cmd_positional_arguments",
+    srcs = ["cmd_positional_arguments.cc"],
+    hdrs = ["cmd_positional_arguments.h"],
+    deps = [
+        "@com_google_absl//absl/status",
+        "@com_google_absl//absl/strings",
+    ],
+)
+
 cc_library(
     name = "subcommand",
     srcs = ["subcommand.cc"],

common/util/cmd_positional_arguments.cc

@@ -0,0 +1,128 @@
+// Copyright 2017-2020 The Verible 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 "common/util/cmd_positional_arguments.h"
+
+#include <string>
+#include <vector>
+
+#include "absl/status/status.h"
+#include "absl/strings/str_split.h"
+#include "absl/strings/string_view.h"
+
+namespace verible {
+
+// Sets a file argument.
+absl::Status CmdPositionalArguments::SetFile(absl::string_view file) {
+  files_.push_back(file);
+  return absl::OkStatus();
+}
+
+// Sets a define arguments.
+absl::Status CmdPositionalArguments::SetDefine(
+    std::pair<absl::string_view, absl::string_view> define) {
+  defines_.push_back(define);
+  return absl::OkStatus();
+}
+
+// Sets a include directory argument.
+absl::Status CmdPositionalArguments::SetIncludeDir(
+    absl::string_view include_dir) {
+  include_dirs_.push_back(include_dir);
+  return absl::OkStatus();
+}
+
+// Gets include directories arguments.
+std::vector<absl::string_view> CmdPositionalArguments::GetIncludeDirs() {
+  return include_dirs_;
+}
+
+std::vector<std::pair<absl::string_view, absl::string_view>>
+
+// Gets macro defines arguments.
+CmdPositionalArguments::GetDefines() {
+  return defines_;
+}
+
+// Gets SV files arguments.
+std::vector<absl::string_view> CmdPositionalArguments::GetFiles() {
+  return files_;
+}
+
+// Main function that parses arguments and add them to the correct data memeber.
+absl::Status CmdPositionalArguments::ParseArgs() {
+  // Positional arguments types:
+  // 1) <file>
+  // 2) +define+<foo>[=<value>]
+  // 3) +incdir+<dir>
+
+  int argument_index = 0;
+  for (absl::string_view argument : all_args_) {
+    if (!argument_index) {
+      argument_index++;
+      continue;
+    }  // all_args_[0] is the tool's name, which can be skipped.
+    if (argument[0] != '+') {  // the argument is a SV file name.
+      if (auto status = SetFile(argument); !status.ok())
+        return status;  // add it to the file arguments.
+    } else {            // it should be either a define or incdir.
+      std::vector<absl::string_view> argument_plus_splitted =
+          absl::StrSplit(argument, absl::ByChar('+'), absl::SkipEmpty());
+      if (argument_plus_splitted.size() < 2) {
+        // Unknown argument.
+        return absl::InvalidArgumentError("Unkown argument.");
+      }
+      absl::string_view plus_argument_type = argument_plus_splitted[0];
+      if (absl::StrContains(plus_argument_type, "define")) {
+        // define argument.
+        int define_argument_index = 0;
+        for (absl::string_view define_argument : argument_plus_splitted) {
+          if (!define_argument_index) {
+            define_argument_index++;
+            continue;
+          }
+          // define_argument is something like <macro1>=<value>.
+          std::pair<absl::string_view, absl::string_view> macro_pair =
+              absl::StrSplit(
+                  define_argument, absl::ByChar('='),
+                  absl::SkipEmpty());  // parse the macro name and value.
+          if (auto status = CmdPositionalArguments::SetDefine(macro_pair);
+              !status.ok())
+            return status;  // add the define argument.
+          define_argument_index++;
+        }
+      } else if (absl::StrContains(plus_argument_type, "incdir")) {
+        // incdir argument.
+        int incdir_argument_index = 0;
+        for (absl::string_view incdir_argument : argument_plus_splitted) {
+          if (!incdir_argument_index) {
+            incdir_argument_index++;
+            continue;
+          }
+          if (auto status =
+                  CmdPositionalArguments::SetIncludeDir(incdir_argument);
+              !status.ok())
+            return status;  // add file argument.
+          incdir_argument_index++;
+        }
+      } else {
+        return absl::InvalidArgumentError("Unkown argument.");
+      }
+    }
+    argument_index++;
+  }
+  return absl::OkStatus();
+}
+
+}  // namespace verible

common/util/cmd_positional_arguments.h

@@ -0,0 +1,67 @@
+// Copyright 2017-2020 The Verible 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 VERIBLE_COMMON_UTIL_CMD_POSITIONAL_ARGUMENTS_H_
+#define VERIBLE_COMMON_UTIL_CMD_POSITIONAL_ARGUMENTS_H_
+
+#include <string>
+#include <vector>
+
+#include "absl/status/status.h"
+#include "absl/strings/string_view.h"
+
+namespace verible {
+
+class CmdPositionalArguments {
+ public:
+  explicit CmdPositionalArguments(const std::vector<char *> &args)
+      : all_args_(args){};
+
+  // Main function that parses arguments.
+  absl::Status ParseArgs();
+
+  // Gets include directories arguments.
+  std::vector<absl::string_view> GetIncludeDirs();
+
+  // Gets macro defines arguments.
+  std::vector<std::pair<absl::string_view, absl::string_view>> GetDefines();
+
+  // Gets SV files arguments.
+  std::vector<absl::string_view> GetFiles();
+
+ private:
+  // Sets a include directory argument.
+  absl::Status SetIncludeDir(absl::string_view include_dir);
+
+  // Sets a define arguments.
+  absl::Status SetDefine(
+      std::pair<absl::string_view, absl::string_view> define);
+
+  // Sets a file argument.
+  absl::Status SetFile(absl::string_view file);
+
+  std::vector<char *>
+      all_args_;  // contains all arguments (tool's name is included).
+  std::vector<absl::string_view>
+      include_dirs_;  // contains all arugments that follows +incdir+<dir>.
+  std::vector<absl::string_view>
+      files_;  // contains all SV files passed to the tool.
+  std::vector<std::pair<absl::string_view, absl::string_view>>
+      defines_;  // contains all arguments that follow +define+<name>[=<value>]
+                 // as a pair<name,value>.
+};               // class CmdPositionalArguments
+
+}  // namespace verible
+
+#endif  // VERIBLE_COMMON_UTIL_CMD_POSITIONAL_ARGUMENTS_H_

verilog/analysis/BUILD

@@ -74,6 +74,18 @@ cc_library(
     ],
 )
 
+cc_library(
+    name = "flow_tree",
+    srcs = ["flow_tree.cc"],
+    hdrs = ["flow_tree.h"],
+    deps = [
+        "//common/lexer:token_stream_adapter",
+        "//verilog/parser:verilog_token_enum",
+        "@com_google_absl//absl/strings",
+        "@com_google_absl//absl/status",
+    ],
+)
+
 cc_library(
     name = "lint_rule_registry",
     srcs = ["lint_rule_registry.cc"],

verilog/analysis/flow_tree.cc

@@ -0,0 +1,147 @@
+// Copyright 2017-2020 The Verible Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance wedge_from_iteratorh 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 wredge_from_iteratoring,
+// software distributed under the License is distributed on an "AS IS" BASIS,
+// Wedge_from_iteratorHOUT WARRANTIES OR CONDedge_from_iteratorIONS OF ANY KIND,
+// eedge_from_iteratorher express or implied. See the License for the specific
+// language governing permissions and limedge_from_iteratorations under the
+// License.
+
+#include "verilog/analysis/flow_tree.h"
+
+#include <map>
+#include <string>
+#include <vector>
+
+#include "absl/status/status.h"
+#include "absl/strings/str_cat.h"
+#include "absl/strings/string_view.h"
+#include "common/lexer/token_stream_adapter.h"
+#include "verilog/parser/verilog_token_enum.h"
+
+namespace verilog {
+
+// Constructs the control flow tree, which determines the edge from each node
+// (token index) to the next possible childs, And save edge_from_iterator in
+// edges_.
+absl::Status FlowTree::GenerateControlFlowTree() {
+  // Adding edges for if blocks.
+  int token_index = 0;
+  int current_token_enum = 0;
+  for (auto current_token : source_sequence_) {
+    current_token_enum = current_token.token_enum();
+
+    if (current_token_enum == PP_ifdef || current_token_enum == PP_ifndef) {
+      ifs_.push_back(token_index);  // add index of `ifdef and `ifndef to ifs_.
+      elses_[ifs_.back()].push_back(
+          token_index);  // also add edge_from_iterator to elses_ as if will
+                         // help marking edges later on.
+
+    } else if (current_token_enum == PP_else ||
+               current_token_enum == PP_elsif ||
+               current_token_enum == PP_endif) {
+      elses_[ifs_.back()].push_back(
+          token_index);  // add index of `elsif, `else and `endif to else_ of
+                         // the last recent if block.
+      if (current_token_enum ==
+          PP_endif) {  // if the current token is an `endif, then we are ready
+                       // to create edges for this if block.
+        auto& current_if_block =
+            elses_[ifs_.back()];  // current_if_block contains all indexes of
+                                  // ifs and elses in the latest block.
+
+        // Adding edges for each index in the if block using a nested loop.
+        for (auto edge_from_iterator = current_if_block.begin();
+             edge_from_iterator != current_if_block.end();
+             edge_from_iterator++) {
+          for (auto edge_to_iterator = edge_from_iterator + 1;
+               edge_to_iterator != current_if_block.end(); edge_to_iterator++) {
+            if (edge_from_iterator == current_if_block.begin() &&
+                edge_to_iterator == current_if_block.end() - 1 &&
+                current_if_block.size() > 2)
+              continue;  // skip edges from `if to `endif if there is an else in
+                         // this bloc wheneven there is an else in this block.
+            edges_[*edge_from_iterator].push_back(
+                *edge_to_iterator +
+                (edge_to_iterator !=
+                 current_if_block.end() - 1));  // add the possible edge.
+          }
+        }
+        ifs_.pop_back();  // the if block edges were added, ready to pop it.
+      }
+    }
+    token_index++;  // increment the token index.
+  }
+
+  // Adding edges for non-if blocks.
+  token_index = 0;
+  for (auto current_token : source_sequence_) {
+    current_token_enum = current_token.token_enum();
+    if (current_token_enum != PP_else && current_token_enum != PP_elsif) {
+      if (token_index > 0)
+        edges_[token_index - 1].push_back(
+            token_index);  // edges from a token to the one coming after it
+                           // directly.
+    } else {
+      if (token_index > 0)
+        edges_[token_index - 1].push_back(
+            edges_[token_index]
+                .back());  // edges from the last token in `ifdef/`ifndef body
+                           // to `endif from the same if block.
+    }
+    token_index++;  // increment the token index.
+  }
+
+  return absl::OkStatus();
+}
+
+// Traveses the control flow tree in a depth first manner, appending the visited
+// tokens to current_sequence_, then adding current_sequence_ to variants_ upon
+// completing.
+absl::Status FlowTree::DepthFirstSearch(int current_node_index) {
+  // skips preprocessor directives so that current_sequence_ doesn't contain
+  // any.
+  const auto& current_token = source_sequence_[current_node_index];
+  if (current_token.token_enum() != PP_Identifier &&
+      current_token.token_enum() != PP_ifndef &&
+      current_token.token_enum() != PP_ifdef &&
+      current_token.token_enum() != PP_define &&
+      current_token.token_enum() != PP_define_body &&
+      current_token.token_enum() != PP_elsif &&
+      current_token.token_enum() != PP_else &&
+      current_token.token_enum() != PP_endif)
+    current_sequence_.push_back(current_token);
+
+  // do recursive search through every possible edge.
+  for (auto next_node : edges_[current_node_index]) {
+    if (auto status = FlowTree::DepthFirstSearch(next_node); !status.ok()) {
+      std::cerr << "ERROR: DepthFirstSearch fails\n";
+      return status;
+    }
+  }
+  if (current_node_index ==
+      int(source_sequence_.size()) -
+          1) {  // if the current node is the last one, push the completed
+                // current_sequence_ to variants_.
+    variants_.push_back(current_sequence_);
+  }
+  if (current_token.token_enum() != PP_Identifier &&
+      current_token.token_enum() != PP_ifndef &&
+      current_token.token_enum() != PP_ifdef &&
+      current_token.token_enum() != PP_define &&
+      current_token.token_enum() != PP_define_body &&
+      current_token.token_enum() != PP_elsif &&
+      current_token.token_enum() != PP_else &&
+      current_token.token_enum() != PP_endif)
+    current_sequence_
+        .pop_back();  // remove tokens to back track into other variants.
+  return absl::OkStatus();
+}
+
+}  // namespace verilog