2 files changed, 117 insertions, 65 deletions

diff --git a/frontends/ast/ast.h b/frontends/ast/ast.h
index 9a5aa15f9..203b50021 100644
--- a/frontends/ast/ast.h
+++ b/frontends/ast/ast.h
@@ -250,7 +250,7 @@ namespace AST
 		// it also sets the id2ast pointers so that identifier lookups are fast in genRTLIL()
 		bool simplify(bool const_fold, bool at_zero, bool in_lvalue, int stage, int width_hint, bool sign_hint, bool in_param);
 		AstNode *readmem(bool is_readmemh, std::string mem_filename, AstNode *memory, int start_addr, int finish_addr, bool unconditional_init);
-		void expand_genblock(std::string index_var, std::string prefix, std::map<std::string, std::string> &name_map);
+		void expand_genblock(std::string index_var, std::string prefix, std::map<std::string, std::string> &name_map, bool original_scope = true);
 		void replace_ids(const std::string &prefix, const std::map<std::string, std::string> &rules);
 		void mem2reg_as_needed_pass1(dict<AstNode*, pool<std::string>> &mem2reg_places,
 				dict<AstNode*, uint32_t> &mem2reg_flags, dict<AstNode*, uint32_t> &proc_flags, uint32_t &status_flags);
diff --git a/frontends/ast/simplify.cc b/frontends/ast/simplify.cc
index 3a652d6cd..ed46e9e32 100644
--- a/frontends/ast/simplify.cc
+++ b/frontends/ast/simplify.cc
@@ -1807,7 +1807,7 @@ bool AstNode::simplify(bool const_fold, bool at_zero, bool in_lvalue, int stage,
 
 			if (type == AST_GENFOR) {
 				for (size_t i = 0; i < buf->children.size(); i++) {
-					buf->children[i]->simplify(false, false, false, stage, -1, false, false);
+					buf->children[i]->simplify(const_fold, false, false, stage, -1, false, false);
 					current_ast_mod->children.push_back(buf->children[i]);
 				}
 			} else {
@@ -1883,7 +1883,7 @@ bool AstNode::simplify(bool const_fold, bool at_zero, bool in_lvalue, int stage,
 		}
 
 		for (size_t i = 0; i < children.size(); i++) {
-			children[i]->simplify(false, false, false, stage, -1, false, false);
+			children[i]->simplify(const_fold, false, false, stage, -1, false, false);
 			current_ast_mod->children.push_back(children[i]);
 		}
 
@@ -1920,7 +1920,7 @@ bool AstNode::simplify(bool const_fold, bool at_zero, bool in_lvalue, int stage,
 			}
 
 			for (size_t i = 0; i < buf->children.size(); i++) {
-				buf->children[i]->simplify(false, false, false, stage, -1, false, false);
+				buf->children[i]->simplify(const_fold, false, false, stage, -1, false, false);
 				current_ast_mod->children.push_back(buf->children[i]);
 			}
 
@@ -1999,7 +1999,7 @@ bool AstNode::simplify(bool const_fold, bool at_zero, bool in_lvalue, int stage,
 			}
 
 			for (size_t i = 0; i < buf->children.size(); i++) {
-				buf->children[i]->simplify(false, false, false, stage, -1, false, false);
+				buf->children[i]->simplify(const_fold, false, false, stage, -1, false, false);
 				current_ast_mod->children.push_back(buf->children[i]);
 			}
 
@@ -3052,7 +3052,7 @@ skip_dynamic_range_lvalue_expansion:;
 			bool all_args_const = true;
 			for (auto child : children) {
 				while (child->simplify(true, false, false, 1, -1, false, true)) { }
-				if (child->type != AST_CONSTANT)
+				if (child->type != AST_CONSTANT && child->type != AST_REALVALUE)
 					all_args_const = false;
 			}
 
@@ -3711,8 +3711,11 @@ AstNode *AstNode::readmem(bool is_readmemh, std::string mem_filename, AstNode *m
 }
 
 // annotate the names of all wires and other named objects in a generate block
-void AstNode::expand_genblock(std::string index_var, std::string prefix, std::map<std::string, std::string> &name_map)
+void AstNode::expand_genblock(std::string index_var, std::string prefix, std::map<std::string, std::string> &name_map, bool original_scope)
 {
+	// `original_scope` defaults to false, and is used to prevent the premature
+	// prefixing of items in named sub-blocks
+
 	if (!index_var.empty() && type == AST_IDENTIFIER && str == index_var) {
 		if (children.empty()) {
 			current_scope[index_var]->children[0]->cloneInto(this);
@@ -3725,53 +3728,85 @@ void AstNode::expand_genblock(std::string index_var, std::string prefix, std::ma
 		}
 	}
 
-	if ((type == AST_IDENTIFIER || type == AST_FCALL || type == AST_TCALL || type == AST_WIRETYPE) && name_map.count(str) > 0)
-		str = name_map[str];
+	if (type == AST_IDENTIFIER || type == AST_FCALL || type == AST_TCALL || type == AST_WIRETYPE) {
+		if (name_map.count(str) > 0) {
+			str = name_map[str];
+		} else {
+			// remap the prefix of this ident if it is a local generate scope
+			size_t pos = str.rfind('.');
+			if (pos != std::string::npos) {
+				std::string existing_prefix = str.substr(0, pos);
+				if (name_map.count(existing_prefix) > 0) {
+					str = name_map[existing_prefix] + str.substr(pos);
+				}
+			}
+		}
+	}
 
 	std::map<std::string, std::string> backup_name_map;
 
+	auto prefix_node = [&](AstNode* child) {
+		if (backup_name_map.size() == 0)
+			backup_name_map = name_map;
+
+		// if within a nested scope
+		if (!original_scope) {
+			// this declaration shadows anything in the parent scope(s)
+			name_map[child->str] = child->str;
+			return;
+		}
+
+		std::string new_name = prefix[0] == '\\' ? prefix.substr(1) : prefix;
+		size_t pos = child->str.rfind('.');
+		if (pos == std::string::npos)
+			pos = child->str[0] == '\\' && prefix[0] == '\\' ? 1 : 0;
+		else
+			pos = pos + 1;
+		new_name = child->str.substr(0, pos) + new_name + child->str.substr(pos);
+		if (new_name[0] != '$' && new_name[0] != '\\')
+			new_name = prefix[0] + new_name;
+
+		name_map[child->str] = new_name;
+		if (child->type == AST_FUNCTION)
+			replace_result_wire_name_in_function(child, child->str, new_name);
+		else
+			child->str = new_name;
+		current_scope[new_name] = child;
+	};
+
 	for (size_t i = 0; i < children.size(); i++) {
 		AstNode *child = children[i];
-		if (child->type == AST_WIRE || child->type == AST_MEMORY || child->type == AST_PARAMETER || child->type == AST_LOCALPARAM ||
-				child->type == AST_FUNCTION || child->type == AST_TASK || child->type == AST_CELL || child->type == AST_TYPEDEF || child->type == AST_ENUM_ITEM) {
-			if (backup_name_map.size() == 0)
-				backup_name_map = name_map;
-			std::string new_name = prefix[0] == '\\' ? prefix.substr(1) : prefix;
-			size_t pos = child->str.rfind('.');
-			if (pos == std::string::npos)
-				pos = child->str[0] == '\\' && prefix[0] == '\\' ? 1 : 0;
-			else
-				pos = pos + 1;
-			new_name = child->str.substr(0, pos) + new_name + child->str.substr(pos);
-			if (new_name[0] != '$' && new_name[0] != '\\')
-				new_name = prefix[0] + new_name;
-			name_map[child->str] = new_name;
-			if (child->type == AST_FUNCTION)
-				replace_result_wire_name_in_function(child, child->str, new_name);
-			else
-				child->str = new_name;
-			current_scope[new_name] = child;
-		}
-		if (child->type == AST_ENUM){
+
+		switch (child->type) {
+		case AST_WIRE:
+		case AST_MEMORY:
+		case AST_PARAMETER:
+		case AST_LOCALPARAM:
+		case AST_FUNCTION:
+		case AST_TASK:
+		case AST_CELL:
+		case AST_TYPEDEF:
+		case AST_ENUM_ITEM:
+		case AST_GENVAR:
+			prefix_node(child);
+			break;
+
+		case AST_BLOCK:
+		case AST_GENBLOCK:
+			if (!child->str.empty())
+				prefix_node(child);
+			break;
+
+		case AST_ENUM:
 			current_scope[child->str] = child;
 			for (auto enode : child->children){
 				log_assert(enode->type == AST_ENUM_ITEM);
-				if (backup_name_map.size() == 0)
-					backup_name_map = name_map;
-				std::string new_name = prefix[0] == '\\' ? prefix.substr(1) : prefix;
-				size_t pos = enode->str.rfind('.');
-				if (pos == std::string::npos)
-					pos = enode->str[0] == '\\' && prefix[0] == '\\' ? 1 : 0;
-				else
-					pos = pos + 1;
-				new_name = enode->str.substr(0, pos) + new_name + enode->str.substr(pos);
-				if (new_name[0] != '$' && new_name[0] != '\\')
-					new_name = prefix[0] + new_name;
-				name_map[enode->str] = new_name;
-
-				enode->str = new_name;
-				current_scope[new_name] = enode;
+				prefix_node(enode);
 			}
+			break;
+
+		default:
+			break;
 		}
 	}
 
@@ -3781,8 +3816,14 @@ void AstNode::expand_genblock(std::string index_var, std::string prefix, std::ma
 		// still needs to recursed-into
 		if (type == AST_PREFIX && i == 1 && child->type == AST_IDENTIFIER)
 			continue;
-		if (child->type != AST_FUNCTION && child->type != AST_TASK)
-			child->expand_genblock(index_var, prefix, name_map);
+		// functions/tasks may reference wires, constants, etc. in this scope
+		if (child->type == AST_FUNCTION || child->type == AST_TASK)
+			child->expand_genblock(index_var, prefix, name_map, false);
+		// continue prefixing if this child block is anonymous
+		else if (child->type == AST_GENBLOCK || child->type == AST_BLOCK)
+			child->expand_genblock(index_var, prefix, name_map, original_scope && child->str.empty());
+		else
+			child->expand_genblock(index_var, prefix, name_map, original_scope);
 	}
 
 
@@ -4370,27 +4411,9 @@ AstNode *AstNode::eval_const_function(AstNode *fcall)
 	size_t argidx = 0;
 	for (auto child : children)
 	{
-		if (child->type == AST_WIRE)
-		{
-			while (child->simplify(true, false, false, 1, -1, false, true)) { }
-			if (!child->range_valid)
-				log_file_error(child->filename, child->location.first_line, "Can't determine size of variable %s\n%s:%d.%d-%d.%d: ... called from here.\n",
-						child->str.c_str(), fcall->filename.c_str(), fcall->location.first_line, fcall->location.first_column, fcall->location.last_line, fcall->location.last_column);
-			variables[child->str].val = RTLIL::Const(RTLIL::State::Sx, abs(child->range_left - child->range_right)+1);
-			variables[child->str].offset = min(child->range_left, child->range_right);
-			variables[child->str].is_signed = child->is_signed;
-			if (child->is_input && argidx < fcall->children.size())
-				variables[child->str].val = fcall->children.at(argidx++)->bitsAsConst(variables[child->str].val.bits.size());
-			backup_scope[child->str] = current_scope[child->str];
-			current_scope[child->str] = child;
-			continue;
-		}
-
 		block->children.push_back(child->clone());
 	}
 
-	log_assert(variables.count(str) != 0);
-
 	while (!block->children.empty())
 	{
 		AstNode *stmt = block->children.front();
@@ -4402,6 +4425,35 @@ AstNode *AstNode::eval_const_function(AstNode *fcall)
 		stmt->dumpAst(NULL, "stmt> ");
 #endif
 
+		if (stmt->type == AST_WIRE)
+		{
+			while (stmt->simplify(true, false, false, 1, -1, false, true)) { }
+			if (!stmt->range_valid)
+				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;
+			if (stmt->is_input && argidx < fcall->children.size()) {
+				int width = variables[stmt->str].val.bits.size();
+				auto* arg_node = fcall->children.at(argidx++);
+				if (arg_node->type == AST_CONSTANT) {
+					variables[stmt->str].val = arg_node->bitsAsConst(width);
+				} else {
+					log_assert(arg_node->type == AST_REALVALUE);
+					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());
+			continue;
+		}
+
+		log_assert(variables.count(str) != 0);
+
 		if (stmt->type == AST_ASSIGN_EQ)
 		{
 			if (stmt->children.at(0)->type == AST_IDENTIFIER && stmt->children.at(0)->children.size() != 0 &&