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Add some (broken) stack handling. Need to move to -mtiny-stack

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This commit is contained in:
Jason Turner
2021-05-08 21:15:21 -06:00
parent d2241528e5
commit baf9c092ea
2 changed files with 86 additions and 27 deletions
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include/personalities/c64.hpp
+9
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@@ -15,6 +15,12 @@ struct C64 : Personality
new_instructions.emplace_back(ASMLine::Type::Directive, "* = " + std::to_string(start_address));
new_instructions.emplace_back(ASMLine::Type::Directive, "; jmp to start of program with BASIC");
new_instructions.emplace_back(ASMLine::Type::Directive, ".byt $0B,$08,$0A,$00,$9E,$32,$30,$36,$31,$00,$00,$00");
// load start of stack space into stack address pointers
new_instructions.emplace_back(mos6502::OpCode::lda, Operand(Operand::Type::literal, "#$FF"));
new_instructions.emplace_back(mos6502::OpCode::sta, Operand(Operand::Type::literal, std::string{stack_low_address()}));
new_instructions.emplace_back(mos6502::OpCode::lda, Operand(Operand::Type::literal, "#$CF"));
new_instructions.emplace_back(mos6502::OpCode::sta, Operand(Operand::Type::literal, std::string{ stack_high_address() }));
}
[[nodiscard]] std::string_view stack_low_address() const override
@@ -94,6 +100,9 @@ struct C64 : Personality
return Operand(Operand::Type::literal, "$5f");
case 31:
return Operand(Operand::Type::literal, "$60");
case 32:
// 32 is the "Stack Pointer", because I decided so, I mean, it makes sense
return Operand(Operand::Type::literal, std::string{stack_low_address()});
}
throw std::runtime_error("Unhandled register number: " + std::to_string(reg_num));
}