diff options
Diffstat (limited to 'frontends/ast')
-rw-r--r-- | frontends/ast/ast.h | 7 | ||||
-rw-r--r-- | frontends/ast/simplify.cc | 147 |
2 files changed, 82 insertions, 72 deletions
diff --git a/frontends/ast/ast.h b/frontends/ast/ast.h index 6f173ca22..d8818df31 100644 --- a/frontends/ast/ast.h +++ b/frontends/ast/ast.h @@ -264,10 +264,9 @@ namespace AST // additional functionality for evaluating constant functions struct varinfo_t { RTLIL::Const val; int offset; bool is_signed; }; - bool has_const_only_constructs(bool &recommend_const_eval); - bool has_const_only_constructs(std::set<std::string>& visited, bool &recommend_const_eval); - void replace_variables(std::map<std::string, varinfo_t> &variables, AstNode *fcall); - AstNode *eval_const_function(AstNode *fcall); + bool has_const_only_constructs(); + bool replace_variables(std::map<std::string, varinfo_t> &variables, AstNode *fcall, bool must_succeed); + AstNode *eval_const_function(AstNode *fcall, bool must_succeed); bool is_simple_const_expr(); std::string process_format_str(const std::string &sformat, int next_arg, int stage, int width_hint, bool sign_hint); diff --git a/frontends/ast/simplify.cc b/frontends/ast/simplify.cc index 77911e966..402b7257b 100644 --- a/frontends/ast/simplify.cc +++ b/frontends/ast/simplify.cc @@ -1218,11 +1218,6 @@ bool AstNode::simplify(bool const_fold, bool at_zero, bool in_lvalue, int stage, current_block = this; current_block_child = children[i]; } - if (!in_param_here && type == AST_FCALL) { - bool recommend_const_eval = false; - bool require_const_eval = has_const_only_constructs(recommend_const_eval); - in_param_here = recommend_const_eval || require_const_eval; - } if ((type == AST_ALWAYS || type == AST_INITIAL) && children[i]->type == AST_BLOCK) current_top_block = children[i]; if (i == 0 && child_0_is_self_determined) @@ -3186,10 +3181,9 @@ skip_dynamic_range_lvalue_expansion:; decl->replace_result_wire_name_in_function(str, "$result"); // enables recursion decl->expand_genblock(prefix); - bool recommend_const_eval = false; - bool require_const_eval = in_param ? false : has_const_only_constructs(recommend_const_eval); - if ((in_param || recommend_const_eval || require_const_eval) && !decl->attributes.count(ID::via_celltype)) + if (decl->type == AST_FUNCTION && !decl->attributes.count(ID::via_celltype)) { + bool require_const_eval = decl->has_const_only_constructs(); bool all_args_const = true; for (auto child : children) { while (child->simplify(true, false, false, 1, -1, false, true)) { } @@ -3200,10 +3194,12 @@ skip_dynamic_range_lvalue_expansion:; if (all_args_const) { AstNode *func_workspace = decl->clone(); func_workspace->str = prefix_id(prefix, "$result"); - newNode = func_workspace->eval_const_function(this); + newNode = func_workspace->eval_const_function(this, in_param || require_const_eval); delete func_workspace; - delete decl; - goto apply_newNode; + if (newNode) { + delete decl; + goto apply_newNode; + } } if (in_param) @@ -4502,33 +4498,12 @@ bool AstNode::detect_latch(const std::string &var) } } -bool AstNode::has_const_only_constructs(bool &recommend_const_eval) +bool AstNode::has_const_only_constructs() { - std::set<std::string> visited; - return has_const_only_constructs(visited, recommend_const_eval); -} - -bool AstNode::has_const_only_constructs(std::set<std::string>& visited, bool &recommend_const_eval) -{ - if (type == AST_FUNCTION || type == AST_TASK) - { - if (visited.count(str)) - { - recommend_const_eval = true; - return false; - } - visited.insert(str); - } - - if (type == AST_FOR) - recommend_const_eval = true; if (type == AST_WHILE || type == AST_REPEAT) return true; - if (type == AST_FCALL && current_scope.count(str)) - if (current_scope[str]->has_const_only_constructs(visited, recommend_const_eval)) - return true; for (auto child : children) - if (child->AstNode::has_const_only_constructs(visited, recommend_const_eval)) + if (child->has_const_only_constructs()) return true; return false; } @@ -4544,19 +4519,26 @@ bool AstNode::is_simple_const_expr() } // helper function for AstNode::eval_const_function() -void AstNode::replace_variables(std::map<std::string, AstNode::varinfo_t> &variables, AstNode *fcall) +bool AstNode::replace_variables(std::map<std::string, AstNode::varinfo_t> &variables, AstNode *fcall, bool must_succeed) { if (type == AST_IDENTIFIER && variables.count(str)) { int offset = variables.at(str).offset, width = variables.at(str).val.bits.size(); if (!children.empty()) { - if (children.size() != 1 || children.at(0)->type != AST_RANGE) + if (children.size() != 1 || children.at(0)->type != AST_RANGE) { + if (!must_succeed) + return false; log_file_error(filename, location.first_line, "Memory access in constant function is not supported\n%s:%d.%d-%d.%d: ...called from here.\n", fcall->filename.c_str(), fcall->location.first_line, fcall->location.first_column, fcall->location.last_line, fcall->location.last_column); - children.at(0)->replace_variables(variables, fcall); + } + if (!children.at(0)->replace_variables(variables, fcall, must_succeed)) + return false; while (simplify(true, false, false, 1, -1, false, true)) { } - if (!children.at(0)->range_valid) + if (!children.at(0)->range_valid) { + if (!must_succeed) + return false; log_file_error(filename, location.first_line, "Non-constant range\n%s:%d.%d-%d.%d: ... called from here.\n", fcall->filename.c_str(), fcall->location.first_line, fcall->location.first_column, fcall->location.last_line, fcall->location.last_column); + } offset = min(children.at(0)->range_left, children.at(0)->range_right); width = min(std::abs(children.at(0)->range_left - children.at(0)->range_right) + 1, width); } @@ -4566,19 +4548,22 @@ void AstNode::replace_variables(std::map<std::string, AstNode::varinfo_t> &varia AstNode *newNode = mkconst_bits(new_bits, variables.at(str).is_signed); newNode->cloneInto(this); delete newNode; - return; + return true; } for (auto &child : children) - child->replace_variables(variables, fcall); + if (!child->replace_variables(variables, fcall, must_succeed)) + return false; + return true; } -// evaluate functions with all-const arguments -AstNode *AstNode::eval_const_function(AstNode *fcall) +// attempt to statically evaluate a functions with all-const arguments +AstNode *AstNode::eval_const_function(AstNode *fcall, bool must_succeed) { - std::map<std::string, AstNode*> backup_scope; + std::map<std::string, AstNode*> backup_scope = current_scope; std::map<std::string, AstNode::varinfo_t> variables; AstNode *block = new AstNode(AST_BLOCK); + AstNode *result = nullptr; size_t argidx = 0; for (auto child : children) @@ -4600,9 +4585,12 @@ AstNode *AstNode::eval_const_function(AstNode *fcall) if (stmt->type == AST_WIRE) { while (stmt->simplify(true, false, false, 1, -1, false, true)) { } - if (!stmt->range_valid) + if (!stmt->range_valid) { + if (!must_succeed) + goto finished; log_file_error(stmt->filename, stmt->location.first_line, "Can't determine size of variable %s\n%s:%d.%d-%d.%d: ... called from here.\n", stmt->str.c_str(), fcall->filename.c_str(), fcall->location.first_line, fcall->location.first_column, fcall->location.last_line, fcall->location.last_column); + } variables[stmt->str].val = RTLIL::Const(RTLIL::State::Sx, abs(stmt->range_left - stmt->range_right)+1); variables[stmt->str].offset = min(stmt->range_left, stmt->range_right); variables[stmt->str].is_signed = stmt->is_signed; @@ -4616,8 +4604,6 @@ AstNode *AstNode::eval_const_function(AstNode *fcall) variables[stmt->str].val = arg_node->realAsConst(width); } } - if (!backup_scope.count(stmt->str)) - backup_scope[stmt->str] = current_scope[stmt->str]; current_scope[stmt->str] = stmt; block->children.erase(block->children.begin()); @@ -4630,8 +4616,6 @@ AstNode *AstNode::eval_const_function(AstNode *fcall) { while (stmt->simplify(true, false, false, 1, -1, false, true)) { } - if (!backup_scope.count(stmt->str)) - backup_scope[stmt->str] = current_scope[stmt->str]; current_scope[stmt->str] = stmt; block->children.erase(block->children.begin()); @@ -4642,32 +4626,46 @@ AstNode *AstNode::eval_const_function(AstNode *fcall) { if (stmt->children.at(0)->type == AST_IDENTIFIER && stmt->children.at(0)->children.size() != 0 && stmt->children.at(0)->children.at(0)->type == AST_RANGE) - stmt->children.at(0)->children.at(0)->replace_variables(variables, fcall); - stmt->children.at(1)->replace_variables(variables, fcall); + if (!stmt->children.at(0)->children.at(0)->replace_variables(variables, fcall, must_succeed)) + goto finished; + if (!stmt->children.at(1)->replace_variables(variables, fcall, must_succeed)) + goto finished; while (stmt->simplify(true, false, false, 1, -1, false, true)) { } if (stmt->type != AST_ASSIGN_EQ) continue; - if (stmt->children.at(1)->type != AST_CONSTANT) + if (stmt->children.at(1)->type != AST_CONSTANT) { + if (!must_succeed) + goto finished; log_file_error(stmt->filename, stmt->location.first_line, "Non-constant expression in constant function\n%s:%d.%d-%d.%d: ... called from here. X\n", fcall->filename.c_str(), fcall->location.first_line, fcall->location.first_column, fcall->location.last_line, fcall->location.last_column); + } - if (stmt->children.at(0)->type != AST_IDENTIFIER) + if (stmt->children.at(0)->type != AST_IDENTIFIER) { + if (!must_succeed) + goto finished; log_file_error(stmt->filename, stmt->location.first_line, "Unsupported composite left hand side in constant function\n%s:%d.%d-%d.%d: ... called from here.\n", fcall->filename.c_str(), fcall->location.first_line, fcall->location.first_column, fcall->location.last_line, fcall->location.last_column); + } - if (!variables.count(stmt->children.at(0)->str)) + if (!variables.count(stmt->children.at(0)->str)) { + if (!must_succeed) + goto finished; log_file_error(stmt->filename, stmt->location.first_line, "Assignment to non-local variable in constant function\n%s:%d.%d-%d.%d: ... called from here.\n", fcall->filename.c_str(), fcall->location.first_line, fcall->location.first_column, fcall->location.last_line, fcall->location.last_column); + } if (stmt->children.at(0)->children.empty()) { variables[stmt->children.at(0)->str].val = stmt->children.at(1)->bitsAsConst(variables[stmt->children.at(0)->str].val.bits.size()); } else { AstNode *range = stmt->children.at(0)->children.at(0); - if (!range->range_valid) + if (!range->range_valid) { + if (!must_succeed) + goto finished; log_file_error(range->filename, range->location.first_line, "Non-constant range\n%s:%d.%d-%d.%d: ... called from here.\n", fcall->filename.c_str(), fcall->location.first_line, fcall->location.first_column, fcall->location.last_line, fcall->location.last_column); + } int offset = min(range->range_left, range->range_right); int width = std::abs(range->range_left - range->range_right) + 1; varinfo_t &v = variables[stmt->children.at(0)->str]; @@ -4694,12 +4692,16 @@ AstNode *AstNode::eval_const_function(AstNode *fcall) if (stmt->type == AST_WHILE) { AstNode *cond = stmt->children.at(0)->clone(); - cond->replace_variables(variables, fcall); + if (!cond->replace_variables(variables, fcall, must_succeed)) + goto finished; while (cond->simplify(true, false, false, 1, -1, false, true)) { } - if (cond->type != AST_CONSTANT) + if (cond->type != AST_CONSTANT) { + if (!must_succeed) + goto finished; log_file_error(stmt->filename, stmt->location.first_line, "Non-constant expression in constant function\n%s:%d.%d-%d.%d: ... called from here.\n", fcall->filename.c_str(), fcall->location.first_line, fcall->location.first_column, fcall->location.last_line, fcall->location.last_column); + } if (cond->asBool()) { block->children.insert(block->children.begin(), stmt->children.at(1)->clone()); @@ -4715,12 +4717,16 @@ AstNode *AstNode::eval_const_function(AstNode *fcall) if (stmt->type == AST_REPEAT) { AstNode *num = stmt->children.at(0)->clone(); - num->replace_variables(variables, fcall); + if (!num->replace_variables(variables, fcall, must_succeed)) + goto finished; while (num->simplify(true, false, false, 1, -1, false, true)) { } - if (num->type != AST_CONSTANT) + if (num->type != AST_CONSTANT) { + if (!must_succeed) + goto finished; log_file_error(stmt->filename, stmt->location.first_line, "Non-constant expression in constant function\n%s:%d.%d-%d.%d: ... called from here.\n", fcall->filename.c_str(), fcall->location.first_line, fcall->location.first_column, fcall->location.last_line, fcall->location.last_column); + } block->children.erase(block->children.begin()); for (int i = 0; i < num->bitsAsConst().as_int(); i++) @@ -4734,7 +4740,8 @@ AstNode *AstNode::eval_const_function(AstNode *fcall) if (stmt->type == AST_CASE) { AstNode *expr = stmt->children.at(0)->clone(); - expr->replace_variables(variables, fcall); + if (!expr->replace_variables(variables, fcall, must_succeed)) + goto finished; while (expr->simplify(true, false, false, 1, -1, false, true)) { } AstNode *sel_case = NULL; @@ -4751,14 +4758,18 @@ AstNode *AstNode::eval_const_function(AstNode *fcall) for (size_t j = 0; j+1 < stmt->children.at(i)->children.size() && !found_match; j++) { AstNode *cond = stmt->children.at(i)->children.at(j)->clone(); - cond->replace_variables(variables, fcall); + if (!cond->replace_variables(variables, fcall, must_succeed)) + goto finished; cond = new AstNode(AST_EQ, expr->clone(), cond); while (cond->simplify(true, false, false, 1, -1, false, true)) { } - if (cond->type != AST_CONSTANT) + if (cond->type != AST_CONSTANT) { + if (!must_succeed) + goto finished; log_file_error(stmt->filename, stmt->location.first_line, "Non-constant expression in constant function\n%s:%d.%d-%d.%d: ... called from here.\n", fcall->filename.c_str(), fcall->location.first_line, fcall->location.first_column, fcall->location.last_line, fcall->location.last_column); + } found_match = cond->asBool(); delete cond; @@ -4790,20 +4801,20 @@ AstNode *AstNode::eval_const_function(AstNode *fcall) continue; } + if (!must_succeed) + goto finished; log_file_error(stmt->filename, stmt->location.first_line, "Unsupported language construct in constant function\n%s:%d.%d-%d.%d: ... called from here.\n", fcall->filename.c_str(), fcall->location.first_line, fcall->location.first_column, fcall->location.last_line, fcall->location.last_column); log_abort(); } - delete block; + result = AstNode::mkconst_bits(variables.at(str).val.bits, variables.at(str).is_signed); - for (auto &it : backup_scope) - if (it.second == NULL) - current_scope.erase(it.first); - else - current_scope[it.first] = it.second; +finished: + delete block; + current_scope = backup_scope; - return AstNode::mkconst_bits(variables.at(str).val.bits, variables.at(str).is_signed); + return result; } void AstNode::allocateDefaultEnumValues() |