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//#define XERR
#include "cpu.ih"
// This function is executed when an op_call_rss opcode is encountered in the
// .bim file. Following this opcode a function index is expected (an
// uint8_t value), indicating the function number to call (see the
// enumeration BuiltinFunction in the file
// support/builtinfunction/builtinfunction.h
//
// If the index exceeds or equals BuiltinSize, an error occurs. Otherwise, the
// indicated built in function is called (see the class Builtin)
// See stack/README for a description of how to interpret the indices: when
// calling functions use indices >= 2 to access arguments (the 1st function
// argument is at d_stack[2]), and use indices < 0 to access local variables
// (the 1st local variable is at d_stack[-1])
void CPU::callRss()
{
size_t funIdx = d_hdr.get<uint8_t>(); // get the function's index
xerr("call rss " << funIdx << ": " << BuiltinFunctions::name(funIdx));
d_stack.push(Variable{}); // push a dummy RA
// xerr("dummy pushed");
d_stack.pushBP();
// xerr("BP pushed");
if (funIdx >= BuiltinFunctions::BuiltinSize)
throw Exception{} << "invalid rss function call at offset " <<
(d_hdr.offset() - 2);
// xerr("Calling " << funIdx);
d_builtin.call(funIdx); // call the builtin function
// xerr("Called " << funIdx);
d_stack.popBP();
// xerr("Popped BP");
d_stack.pop(); // remove the dummy RA
// xerr("Popped dummy");
}
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