private List<AsmInstruction> performColoring(List<AsmInstruction> program) {
        AlphaSubstitution colorSubstitution = new AlphaSubstitution();
        for (InterferenceNode node : graph.allNodes()) {
            colorSubstitution.addSubstitution(node.register.getName(), node.color.x86Name());
        }
        List<AsmInstruction> coloredProgram = program.stream().
                                                      flatMap(inst -> colorInstruction(inst, colorSubstitution)).
                                                      collect(Collectors.toList());
        coloredProgram.addAll(0, generateSaveStackSpaceInstructions());
        return coloredProgram;
    }

    private List<AsmInstruction> generateSaveStackSpaceInstructions() {
        return Arrays.asList(AsmInstruction.push(new X86Register(Reg.rbp)),
                             AsmInstruction.mov(new X86Register(Reg.rbp), new X86Register(Reg.rsp)),
                             AsmInstruction.sub(new X86Register(Reg.rsp), new ConstImmediate(nextStackLocation)));
    }