From 4f0c2862a0d7e1ca247e0a4d54301c7f8cc92fd8 Mon Sep 17 00:00:00 2001
From: Clifford Wolf <clifford@clifford.at>
Date: Tue, 26 Feb 2013 13:18:22 +0100
Subject: [PATCH] Added support for verilog genblock[index].member syntax

---
 frontends/ast/ast.cc       |  1 +
 frontends/ast/ast.h        |  1 +
 frontends/ast/simplify.cc  | 16 +++++++++++++++-
 frontends/verilog/parser.y | 26 ++++++++++++++++----------
 4 files changed, 33 insertions(+), 11 deletions(-)

diff --git a/frontends/ast/ast.cc b/frontends/ast/ast.cc
index 160e9c429..e5db5a94b 100644
--- a/frontends/ast/ast.cc
+++ b/frontends/ast/ast.cc
@@ -77,6 +77,7 @@ std::string AST::type2str(AstNodeType type)
 	X(AST_CONSTANT)
 	X(AST_CELLTYPE)
 	X(AST_IDENTIFIER)
+	X(AST_PREFIX)
 	X(AST_FCALL)
 	X(AST_TO_SIGNED)
 	X(AST_TO_UNSIGNED)
diff --git a/frontends/ast/ast.h b/frontends/ast/ast.h
index f7c9328c2..cdc56fba4 100644
--- a/frontends/ast/ast.h
+++ b/frontends/ast/ast.h
@@ -56,6 +56,7 @@ namespace AST
 		AST_CONSTANT,
 		AST_CELLTYPE,
 		AST_IDENTIFIER,
+		AST_PREFIX,
 
 		AST_FCALL,
 		AST_TO_SIGNED,
diff --git a/frontends/ast/simplify.cc b/frontends/ast/simplify.cc
index cb8b1043f..33776d655 100644
--- a/frontends/ast/simplify.cc
+++ b/frontends/ast/simplify.cc
@@ -103,7 +103,7 @@ bool AstNode::simplify(bool const_fold, bool at_zero, bool in_lvalue, int stage)
 	}
 
 	// activate const folding if this is anything that must be evaluated statically (ranges, parameters, attributes, etc.)
-	if (type == AST_WIRE || type == AST_PARAMETER || type == AST_LOCALPARAM || type == AST_PARASET || type == AST_RANGE)
+	if (type == AST_WIRE || type == AST_PARAMETER || type == AST_LOCALPARAM || type == AST_PARASET || type == AST_RANGE || type == AST_PREFIX)
 		const_fold = true;
 	if (type == AST_IDENTIFIER && current_scope.count(str) > 0 && (current_scope[str]->type == AST_PARAMETER || current_scope[str]->type == AST_LOCALPARAM))
 		const_fold = true;
@@ -179,6 +179,8 @@ bool AstNode::simplify(bool const_fold, bool at_zero, bool in_lvalue, int stage)
 			break;
 		if (type == AST_GENIF && i >= 1)
 			break;
+		if (type == AST_PREFIX && i >= 1)
+			break;
 		while (did_something_here && i < children.size()) {
 			bool const_fold_here = const_fold, in_lvalue_here = in_lvalue;
 			if (i == 0 && type == AST_REPLICATE)
@@ -217,6 +219,18 @@ bool AstNode::simplify(bool const_fold, bool at_zero, bool in_lvalue, int stage)
 	if (type == AST_MODULE)
 		current_scope.clear();
 
+	// resolve constant prefixes
+	if (type == AST_PREFIX) {
+		if (children[0]->type != AST_CONSTANT) {
+			dumpAst(NULL, ">   ", NULL);
+			log_error("Index in generate block prefix syntax at %s:%d is not constant!\n", filename.c_str(), linenum);
+		}
+		assert(children[1]->type == AST_IDENTIFIER);
+		newNode = children[1]->clone();
+		newNode->str = stringf("%s[%d].%s", str.c_str(), children[0]->integer, children[1]->str.c_str());
+		goto apply_newNode;
+	}
+
 	// annotate constant ranges
 	if (type == AST_RANGE) {
 		bool old_range_valid = range_valid;
diff --git a/frontends/verilog/parser.y b/frontends/verilog/parser.y
index 010af4787..6e0b238e0 100644
--- a/frontends/verilog/parser.y
+++ b/frontends/verilog/parser.y
@@ -105,7 +105,7 @@ static void free_attr(std::map<std::string, AstNode*> *al)
 %token TOK_SYNOPSYS_FULL_CASE TOK_SYNOPSYS_PARALLEL_CASE
 %token TOK_SUPPLY0 TOK_SUPPLY1 TOK_TO_SIGNED TOK_TO_UNSIGNED
 
-%type <ast> wire_type range expr basic_expr concat_list lvalue lvalue_concat_list
+%type <ast> wire_type range expr basic_expr concat_list rvalue lvalue lvalue_concat_list
 %type <string> opt_label tok_prim_wrapper
 %type <boolean> opt_signed
 %type <al> attr
@@ -802,13 +802,21 @@ case_expr_list:
 		ast_stack.back()->children.push_back($3);
 	};
 
-lvalue:
+rvalue:
+	TOK_ID '[' expr ']' '.' rvalue {
+		$$ = new AstNode(AST_PREFIX, $3, $6);
+		$$->str = *$1;
+		delete $1;
+	} |
 	TOK_ID range {
-		$$ = new AstNode(AST_IDENTIFIER);
+		$$ = new AstNode(AST_IDENTIFIER, $2);
 		$$->str = *$1;
-		if ($2)
-			$$->children.push_back($2);
 		delete $1;
+	};
+
+lvalue:
+	rvalue {
+		$$ = $1;
 	} |
 	'{' lvalue_concat_list '}' {
 		$$ = $2;
@@ -894,6 +902,9 @@ expr:
 	};
 
 basic_expr:
+	rvalue {
+		$$ = $1;
+	} |
 	TOK_CONST {
 		$$ = const2ast(*$1, case_type_stack.size() == 0 ? 0 : case_type_stack.back());
 		delete $1;
@@ -913,11 +924,6 @@ basic_expr:
 		$$->str = str;
 		delete $1;
 	} |
-	TOK_ID range {
-		$$ = new AstNode(AST_IDENTIFIER, $2);
-		$$->str = *$1;
-		delete $1;
-	} |
 	TOK_ID attr {
 		AstNode *node = new AstNode(AST_FCALL);
 		node->str = *$1;
-- 
2.30.2