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Merge pull request #1372 from karimtera/pp_generate_variants_mode
[VeriblePreProcessor][1]: multiple-cu and generate-variants modes
2 parents 4faba50 + 37cc052 commit 7e6dda3

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+1287
-13
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‎verilog/analysis/BUILD‎

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@@ -74,6 +74,34 @@ cc_library(
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],
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)
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cc_library(
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name = "flow_tree",
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srcs = ["flow_tree.cc"],
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hdrs = ["flow_tree.h"],
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deps = [
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"//common/lexer:token_stream_adapter",
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"//verilog/parser:verilog_token_enum",
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"@com_google_absl//absl/strings",
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"@com_google_absl//absl/status",
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],
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)
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cc_test(
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name = "flow_tree_test",
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srcs = ["flow_tree_test.cc"],
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deps = [
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":flow_tree",
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"//common/util:logging",
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"//common/lexer:token_stream_adapter",
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"//verilog/parser:verilog_lexer",
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"//verilog/parser:verilog_token_enum",
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"@com_google_absl//absl/memory",
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"@com_google_absl//absl/strings",
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"@com_google_googletest//:gtest_main",
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],
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)
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cc_library(
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name = "lint_rule_registry",
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srcs = ["lint_rule_registry.cc"],

‎verilog/analysis/flow_tree.cc‎

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// Copyright 2017-2022 The Verible Authors.
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing,
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// software distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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#include "verilog/analysis/flow_tree.h"
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#include <map>
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#include <string>
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#include <vector>
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#include "absl/status/status.h"
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#include "absl/strings/str_cat.h"
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#include "absl/strings/string_view.h"
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#include "common/lexer/token_stream_adapter.h"
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#include "verilog/parser/verilog_token_enum.h"
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namespace verilog {
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// Adds edges within a conditonal block.
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// Such that the first edge represents the condition being true,
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// and the second edge represents the condition being false.
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absl::Status FlowTree::AddBlockEdges(const ConditionalBlock &block) {
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bool contains_elsif = !block.elsif_locations.empty();
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bool contains_else = block.else_location != source_sequence_.end();
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// Handling `ifdef/ifndef.
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// Assuming the condition is true.
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edges_[block.if_location].push_back(block.if_location + 1);
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// Assuming the condition is false.
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// Checking if there is an `elsif.
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if (contains_elsif) {
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// Add edge to the first `elsif in the block.
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edges_[block.if_location].push_back(block.elsif_locations[0]);
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} else if (contains_else) {
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// Checking if there is an `else.
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edges_[block.if_location].push_back(block.else_location);
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} else {
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// `endif exists.
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edges_[block.if_location].push_back(block.endif_location);
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}
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// Handling `elsif.
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if (contains_elsif) {
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for (auto iter = block.elsif_locations.begin();
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iter != block.elsif_locations.end(); iter++) {
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// Assuming the condition is true.
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edges_[*iter].push_back((*iter) + 1);
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// Assuming the condition is false.
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if (iter + 1 != block.elsif_locations.end())
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edges_[*iter].push_back(*(iter + 1));
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else if (contains_else)
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edges_[*iter].push_back(block.else_location);
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else
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edges_[*iter].push_back(block.endif_location);
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}
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}
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// Handling `else.
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if (contains_else) {
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edges_[block.else_location].push_back(block.else_location + 1);
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}
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// For edges that are generated assuming the conditons are true,
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// We need to add an edge from the end of the condition group of lines to
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// `endif, e.g. `ifdef
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// <line1>
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// <line2>
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// ...
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// <line_final>
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// `else
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// <group_of_lines>
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// `endif
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// Edge to be added: from <line_final> to `endif.
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edges_[block.endif_location - 1].push_back(block.endif_location);
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if (contains_elsif) {
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for (auto iter : block.elsif_locations)
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edges_[iter - 1].push_back(block.endif_location);
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}
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if (contains_else) {
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edges_[block.else_location - 1].push_back(block.endif_location);
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}
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// Connecting `endif to the next token directly (if not EOF).
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auto next_iter = block.endif_location + 1;
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if (next_iter != source_sequence_.end() &&
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next_iter->token_enum() != PP_else &&
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next_iter->token_enum() != PP_elsif &&
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next_iter->token_enum() != PP_endif) {
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edges_[block.endif_location].push_back(next_iter);
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}
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return absl::OkStatus();
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}
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// Checks if the iterator is pointing to a conditional directive.
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bool FlowTree::IsConditional(TokenSequenceConstIterator iterator) {
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auto current_node = iterator->token_enum();
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return current_node == PP_ifndef || current_node == PP_ifdef ||
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current_node == PP_elsif || current_node == PP_else ||
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current_node == PP_endif;
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}
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// Checks if after the conditional_iterator (`ifdef/`ifndef... ) there exists
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// a macro identifier.
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absl::Status FlowTree::MacroFollows(
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TokenSequenceConstIterator conditional_iterator) {
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if (conditional_iterator->token_enum() != PP_ifdef &&
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conditional_iterator->token_enum() != PP_ifndef &&
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conditional_iterator->token_enum() != PP_elsif) {
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return absl::InvalidArgumentError("Error macro name can't be extracted.");
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}
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auto macro_iterator = conditional_iterator + 1;
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if (macro_iterator->token_enum() != PP_Identifier)
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return absl::InvalidArgumentError("Expected identifier for macro name.");
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else
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return absl::OkStatus();
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}
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// Adds a conditional macro to conditional_macros_ if not added before,
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// And gives it a new ID, then saves the ID in conditional_macro_id_ map.
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absl::Status FlowTree::AddMacroOfConditional(
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TokenSequenceConstIterator conditional_iterator) {
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auto status = MacroFollows(conditional_iterator);
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if (!status.ok()) {
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return absl::InvalidArgumentError(
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"Error no macro follows the conditional directive.");
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}
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auto macro_iterator = conditional_iterator + 1;
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auto macro_identifier = macro_iterator->text();
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if (conditional_macro_id_.find(macro_identifier) ==
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conditional_macro_id_.end()) {
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conditional_macro_id_[macro_identifier] = conditional_macros_counter_;
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conditional_macros_.push_back(macro_iterator);
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conditional_macros_counter_++;
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}
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return absl::OkStatus();
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}
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// Gets the conditonal macro ID from the conditional_macro_id_.
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// Note: conditional_iterator is pointing to the conditional.
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int FlowTree::GetMacroIDOfConditional(
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TokenSequenceConstIterator conditional_iterator) {
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auto status = MacroFollows(conditional_iterator);
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if (!status.ok()) {
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// TODO(karimtera): add a better error handling.
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return -1;
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}
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auto macro_iterator = conditional_iterator + 1;
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auto macro_identifier = macro_iterator->text();
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// It is always assumed that the macro already exists in the map.
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return conditional_macro_id_[macro_identifier];
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}
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// An API that provides a callback function to receive variants.
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absl::Status FlowTree::GenerateVariants(const VariantReceiver &receiver) {
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auto status = GenerateControlFlowTree();
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if (!status.ok()) {
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return status;
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}
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return DepthFirstSearch(receiver, source_sequence_.begin());
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}
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// Constructs the control flow tree, which determines the edge from each node
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// (token index) to the next possible childs, And save edge_from_iterator in
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// edges_.
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absl::Status FlowTree::GenerateControlFlowTree() {
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// Adding edges for if blocks.
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int current_token_enum = 0;
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ConditionalBlock empty_block;
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empty_block.if_location = source_sequence_.end();
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empty_block.else_location = source_sequence_.end();
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empty_block.endif_location = source_sequence_.end();
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for (TokenSequenceConstIterator iter = source_sequence_.begin();
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iter != source_sequence_.end(); iter++) {
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current_token_enum = iter->token_enum();
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if (IsConditional(iter)) {
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switch (current_token_enum) {
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case PP_ifdef: {
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if_blocks_.push_back(empty_block);
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if_blocks_.back().if_location = iter;
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if_blocks_.back().positive_condition = 1;
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auto status = AddMacroOfConditional(iter);
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if (!status.ok()) {
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return absl::InvalidArgumentError(
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"ERROR: couldn't give a macro an ID.");
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}
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break;
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}
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case PP_ifndef: {
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if_blocks_.push_back(empty_block);
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if_blocks_.back().if_location = iter;
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if_blocks_.back().positive_condition = 0;
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auto status = AddMacroOfConditional(iter);
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if (!status.ok()) {
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return absl::InvalidArgumentError(
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"ERROR: couldn't give a macro an ID.");
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}
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break;
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}
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case PP_elsif: {
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if (if_blocks_.empty()) {
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return absl::InvalidArgumentError("ERROR: Unmatched `elsif.");
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}
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if_blocks_.back().elsif_locations.push_back(iter);
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auto status = AddMacroOfConditional(iter);
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if (!status.ok()) {
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return absl::InvalidArgumentError(
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"ERROR: couldn't give a macro an ID.");
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}
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break;
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}
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case PP_else: {
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if (if_blocks_.empty()) {
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return absl::InvalidArgumentError("ERROR: Unmatched `else.");
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}
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if_blocks_.back().else_location = iter;
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break;
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}
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case PP_endif: {
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if (if_blocks_.empty()) {
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return absl::InvalidArgumentError("ERROR: Unmatched `endif.");
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}
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if_blocks_.back().endif_location = iter;
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auto status = AddBlockEdges(if_blocks_.back());
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if (!status.ok()) return status;
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// TODO(karimtera): add an error message.
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if_blocks_.pop_back();
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break;
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}
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}
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} else {
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// Only add normal edges if the next token is not `else/`elsif/`endif.
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auto next_iter = iter + 1;
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if (next_iter != source_sequence_.end() &&
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next_iter->token_enum() != PP_else &&
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next_iter->token_enum() != PP_elsif &&
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next_iter->token_enum() != PP_endif) {
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edges_[iter].push_back(next_iter);
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}
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}
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}
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// Checks for uncompleted conditionals.
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if (!if_blocks_.empty())
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return absl::InvalidArgumentError(
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"ERROR: Uncompleted conditional is found.");
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return absl::OkStatus();
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}
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// Traveses the control flow tree in a depth first manner, appending the visited
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// tokens to current_variant_, then provide the completed variant to the user
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// using a callback function (VariantReceiver).
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absl::Status FlowTree::DepthFirstSearch(
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const VariantReceiver &receiver, TokenSequenceConstIterator current_node) {
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if (!wants_more_) return absl::OkStatus();
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// Skips directives so that current_variant_ doesn't contain any.
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if (current_node->token_enum() != PP_Identifier &&
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current_node->token_enum() != PP_ifndef &&
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current_node->token_enum() != PP_ifdef &&
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current_node->token_enum() != PP_define &&
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current_node->token_enum() != PP_define_body &&
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current_node->token_enum() != PP_elsif &&
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current_node->token_enum() != PP_else &&
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current_node->token_enum() != PP_endif) {
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current_variant_.sequence.push_back(*current_node);
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}
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// Checks if the current token is a `ifdef/`ifndef/`elsif.
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if (current_node->token_enum() == PP_ifdef ||
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current_node->token_enum() == PP_ifndef ||
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current_node->token_enum() == PP_elsif) {
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int macro_id = GetMacroIDOfConditional(current_node);
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bool negated = (current_node->token_enum() == PP_ifndef);
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// Checks if this macro is already visited (either defined/undefined).
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if (current_variant_.visited.test(macro_id)) {
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bool assume_condition_is_true =
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(negated ^ current_variant_.macros_mask.test(macro_id));
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if (auto status = DepthFirstSearch(
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receiver, edges_[current_node][!assume_condition_is_true]);
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!status.ok()) {
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std::cerr << "ERROR: DepthFirstSearch fails.";
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return status;
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}
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} else {
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current_variant_.visited.flip(macro_id);
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// This macro wans't visited before, then we can check both edges.
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// Assume the condition is true.
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if (negated)
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current_variant_.macros_mask.reset(macro_id);
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else
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current_variant_.macros_mask.set(macro_id);
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if (auto status = DepthFirstSearch(receiver, edges_[current_node][0]);
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!status.ok()) {
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std::cerr << "ERROR: DepthFirstSearch fails.";
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return status;
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}
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// Assume the condition is false.
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if (!negated)
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current_variant_.macros_mask.reset(macro_id);
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else
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current_variant_.macros_mask.set(macro_id);
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if (auto status = DepthFirstSearch(receiver, edges_[current_node][1]);
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!status.ok()) {
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std::cerr << "ERROR: DepthFirstSearch fails.";
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return status;
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}
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// Undo the change to allow for backtracking.
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current_variant_.visited.flip(macro_id);
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}
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} else {
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// Do recursive search through every possible edge.
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// Expected to be only one edge in this case.
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for (auto next_node : edges_[current_node]) {
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if (auto status = FlowTree::DepthFirstSearch(receiver, next_node);
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!status.ok()) {
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std::cerr << "ERROR: DepthFirstSearch fails\n";
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return status;
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}
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}
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}
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// If the current node is the last one, push the completed current_variant_
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// then it is ready to be sent.
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if (current_node == source_sequence_.end() - 1) {
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wants_more_ &= receiver(current_variant_);
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}
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if (current_node->token_enum() != PP_Identifier &&
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current_node->token_enum() != PP_ifndef &&
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current_node->token_enum() != PP_ifdef &&
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current_node->token_enum() != PP_define &&
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current_node->token_enum() != PP_define_body &&
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current_node->token_enum() != PP_elsif &&
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current_node->token_enum() != PP_else &&
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current_node->token_enum() != PP_endif) {
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// Remove tokens to back track into other variants.
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current_variant_.sequence.pop_back();
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}
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return absl::OkStatus();
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}
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} // namespace verilog

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