INTERFACE JunoAssemble;

IMPORT JunoRT, JunoScope, JunoCompileRep;

TYPE CmdType = { Pred, Func, Proc };

PROCEDURE Cmd(
    cmd: JunoCompileRep.Result;
    scp: JunoScope.T;
    temp_cnt: CARDINAL;
    type: CmdType):
    JunoRT.ByteStream;

Returns the byte-code program produced by assembling the compilation result cmd under the scope scp. The first instruction in the resulting stream increments the stack pointer by temp_cnt locations in order to make space for temporary (local) variables.

The type reflects the kind of declaration in which this command is being compiled. Each type makes certain assumptions about the input command cmd, and handles run-time errors and the state of the machine on return differently. In particular:

type = CmdType.Pred OR type = CmdType.Func => Cmd may be a partial command, but it is required not to abort. Execution of the resulting bytestream is guaranteed to terminate with the machine's condition bit set iff Grd(cmd) # FALSE.

type = CmdType.Proc, => Requires that cmd be a total command. If cmd aborts, the resulting bytestream will execute the run-time bytecode JunoByteCode.ERROR with the appropriate argument (encountered ABORT, IF..FI failure, or undefined term).

This procedure has the side-effect of setting the start and end fields of every AST node of the AST cmd.cmd. Each node n is annotated such that the half-open interval [n.start, n.end) is the largest interval containing the PC locations corresponding the assembly instructions for n.

END JunoAssemble.