v86/gen/c_ast.js

"use strict";

function repeat(s, n)
{
    let out = "";
    for(let i = 0; i < n; i++) out += s;
    return out;
}

function indent(lines, how_much)
{
    return lines.map(line => repeat(" ", how_much) + line);
}

function print_syntax_tree(statements)
{
    let code = [];

    for(let statement of statements)
    {
        if(typeof statement === "string")
        {
            code.push(statement);
        }
        else if(statement.type === "switch")
        {
            console.assert(statement.condition);

            const cases = [];

            for(let case_ of statement.cases)
            {
                console.assert(case_.conditions.length >= 1);

                for(let condition of case_.conditions)
                {
                    cases.push(`case ${condition}:`);
                }

                cases.push(`{`);
                cases.push.apply(cases, indent(print_syntax_tree(case_.body), 4));
                cases.push(`}`);
                cases.push(`break;`);
            }

            if(statement.default_case)
            {
                cases.push(`default:`);
                cases.push.apply(cases, indent(print_syntax_tree(statement.default_case.body), 4));
            }

            code.push(`switch(${statement.condition})`);
            code.push(`{`);
            code.push.apply(code, indent(cases, 4));
            code.push(`}`);
        }
        else if(statement.type === "if-else")
        {
            console.assert(statement.if_blocks.length >= 1);

            let first_if_block = statement.if_blocks[0];

            code.push(`if(${first_if_block.condition})`);
            code.push(`{`);
            code.push.apply(code, indent(print_syntax_tree(first_if_block.body), 4));
            code.push(`}`);

            for(let i = 1; i < statement.if_blocks.length; i++)
            {
                let if_block = statement.if_blocks[i];

                code.push(`else if(${if_block.condition})`);
                code.push(`{`);
                code.push.apply(code, indent(print_syntax_tree(if_block.body), 4));
                code.push(`}`);
            }

            if(statement.else_block)
            {
                code.push(`else`);
                code.push(`{`);
                code.push.apply(code, indent(print_syntax_tree(statement.else_block.body), 4));
                code.push(`}`);
            }
        }
        else
        {
            console.assert(false, "Unexpected type: " + statement.type);
        }
    }

    return code;
}

module.exports = {
    print_syntax_tree,
};