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Merge pull request #5152 from garytwong/unique-if

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verilog: implement SystemVerilog unique/unique0/priority if semantics.
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KrystalDelusion 2025-06-13 09:56:53 +12:00 • committed by GitHub
commit 82888580ac
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6 changed files with 204 additions and 17 deletions
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44
frontends/verilog/verilog_parser.y
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@ -2873,16 +2873,34 @@ behavioral_stmt:
ast_stack.pop_back();
} |
if_attr TOK_IF '(' expr ')' {
AstNode *node = new AstNode(AST_CASE);
AstNode *node = 0;
AstNode *context = ast_stack.back();
if (context && context->type == AST_BLOCK && context->get_bool_attribute(ID::promoted_if)) {
AstNode *outer = ast_stack[ast_stack.size() - 2];
log_assert (outer && outer->type == AST_CASE);
if (outer->get_bool_attribute(ID::parallel_case)) {
// parallel "else if": append condition to outer "if"
node = outer;
log_assert (node->children.size());
delete node->children.back();
node->children.pop_back();
} else if (outer->get_bool_attribute(ID::full_case))
(*$1)[ID::full_case] = AstNode::mkconst_int(1, false);
}
AstNode *expr = new AstNode(AST_REDUCE_BOOL, $4);
if (!node) {
// not parallel "else if": begin new construction
node = new AstNode(AST_CASE);
append_attr(node, $1);
ast_stack.back()->children.push_back(node);
node->children.push_back(node->get_bool_attribute(ID::parallel_case) ? AstNode::mkconst_int(1, false, 1) : expr);
}
AstNode *block = new AstNode(AST_BLOCK);
AstNode *cond = new AstNode(AST_COND, AstNode::mkconst_int(1, false, 1), block);
AstNode *cond = new AstNode(AST_COND, node->get_bool_attribute(ID::parallel_case) ? expr : AstNode::mkconst_int(1, false, 1), block);
SET_AST_NODE_LOC(cond, @4, @4);
ast_stack.back()->children.push_back(node);
node->children.push_back(new AstNode(AST_REDUCE_BOOL, $4));
node->children.push_back(cond);
ast_stack.push_back(node);
ast_stack.push_back(block);
append_attr(node, $1);
} behavioral_stmt {
SET_AST_NODE_LOC(ast_stack.back(), @7, @7);
} optional_else {
@ -2908,21 +2926,25 @@ if_attr:
} |
attr TOK_UNIQUE0 {
AstNode *context = ast_stack.back();
if( context && context->type == AST_BLOCK && context->get_bool_attribute(ID::promoted_if) )
if (context && context->type == AST_BLOCK && context->get_bool_attribute(ID::promoted_if))
frontend_verilog_yyerror("unique0 keyword cannot be used for 'else if' branch.");
$$ = $1; // accept unique0 keyword, but ignore it for now
(*$1)[ID::parallel_case] = AstNode::mkconst_int(1, false);
$$ = $1;
} |
attr TOK_PRIORITY {
AstNode *context = ast_stack.back();
if( context && context->type == AST_BLOCK && context->get_bool_attribute(ID::promoted_if) )
if (context && context->type == AST_BLOCK && context->get_bool_attribute(ID::promoted_if))
frontend_verilog_yyerror("priority keyword cannot be used for 'else if' branch.");
$$ = $1; // accept priority keyword, but ignore it for now
(*$1)[ID::full_case] = AstNode::mkconst_int(1, false);
$$ = $1;
} |
attr TOK_UNIQUE {
AstNode *context = ast_stack.back();
if( context && context->type == AST_BLOCK && context->get_bool_attribute(ID::promoted_if) )
if (context && context->type == AST_BLOCK && context->get_bool_attribute(ID::promoted_if))
frontend_verilog_yyerror("unique keyword cannot be used for 'else if' branch.");
$$ = $1; // accept unique keyword, but ignore it for now
(*$1)[ID::full_case] = AstNode::mkconst_int(1, false);
(*$1)[ID::parallel_case] = AstNode::mkconst_int(1, false);
$$ = $1;
};
case_attr: