Files
rgbds/include/asm/rpn.hpp
Sylvie 2706f94788 Multiple fixes and enhancements to RPN behavior: (#1448)
- FIX: `Label & const` was not actually doing the `& const` masking
  (fixes #1446)
- ADD: `LOW(Label)` can be constant if `Label` is aligned to 8 or more bits
  (resolves #1444)
- ADD: `!expr` can be constant 0 if `expr` has any non-zero bits
  (resolves #1447)
- `LOW()` and `HIGH()` have their own RPN operator values
  (resolves #1445)

The change to RPN values means that the object file version was incremented.

This also refactors unary operators and functions, combining their
evaluation similarly to binary ones.
2024-08-06 13:54:55 +02:00

65 lines
1.8 KiB
C++

/* SPDX-License-Identifier: MIT */
#ifndef RGBDS_ASM_RPN_HPP
#define RGBDS_ASM_RPN_HPP
#include <stdint.h>
#include <string>
#include <variant>
#include <vector>
#include "linkdefs.hpp"
struct Symbol;
struct Expression {
std::variant<
int32_t, // If the expression's value is known, it's here
std::string // Why the expression is not known, if it isn't
> data = 0;
bool isSymbol = false; // Whether the expression represents a symbol suitable for const diffing
std::vector<uint8_t> rpn{}; // Bytes serializing the RPN expression
uint32_t rpnPatchSize = 0; // Size the expression will take in the object file
Expression() = default;
Expression(Expression &&) = default;
#ifdef _MSC_VER
// MSVC and WinFlexBison won't build without this...
Expression(Expression const &) = default;
#endif
Expression &operator=(Expression &&) = default;
bool isKnown() const { return std::holds_alternative<int32_t>(data); }
int32_t value() const;
int32_t getConstVal() const;
Symbol const *symbolOf() const;
bool isDiffConstant(Symbol const *symName) const;
void makeNumber(uint32_t value);
void makeSymbol(std::string const &symName);
void makeBankSymbol(std::string const &symName);
void makeBankSection(std::string const &sectName);
void makeSizeOfSection(std::string const &sectName);
void makeStartOfSection(std::string const &sectName);
void makeSizeOfSectionType(SectionType type);
void makeStartOfSectionType(SectionType type);
void makeUnaryOp(RPNCommand op, Expression &&src);
void makeBinaryOp(RPNCommand op, Expression &&src1, Expression const &src2);
void makeCheckHRAM();
void makeCheckRST();
void checkNBit(uint8_t n) const;
private:
void clear();
uint8_t *reserveSpace(uint32_t size);
uint8_t *reserveSpace(uint32_t size, uint32_t patchSize);
};
bool checkNBit(int32_t v, uint8_t n, char const *name);
#endif // RGBDS_ASM_RPN_HPP