mpw/toolbox/stackframe.h
2015-02-18 12:00:21 -05:00

121 lines
2.7 KiB
C++

#ifndef __StackFrame_h__
#define __StackFrame_h__
#include <cstdint>
#include <utility>
//
template<int Bytes>
void Push__(uint32_t sp)
{
static_assert(Bytes == 0, "Invalid Stack Size");
}
template<int Bytes, typename... Args>
void Push__(uint32_t sp, uint16_t value, Args&&... args);
template<int Bytes, typename... Args>
void Push__(uint32_t sp, uint32_t value, Args&&... args);
template<int Bytes, typename... Args>
void Push__(uint32_t sp, uint16_t value, Args&&... args)
{
memoryWriteWord(value, sp);
Push__<Bytes-2>(sp + 2, std::forward<Args>(args)...);
}
template<int Bytes, typename... Args>
void Push__(uint32_t sp, uint32_t value, Args&&... args)
{
memoryWriteLong(value, sp);
Push__<Bytes-4>(sp + 4, std::forward<Args>(args)...);
}
template<int Bytes, typename... Args>
void Push(Args&&... args)
{
uint32_t sp = cpuGetAReg(7) - Bytes;
cpuSetAReg(7, sp);
Push__<Bytes>(sp, std::forward<Args>(args)...);
}
template<unsigned N>
void ToolReturn(uint32_t sp, uint32_t value)
{
if (sp == -1) sp = cpuGetAReg(7);
static_assert(N == 2 || N == 4, "Invalid Return Size");
if (N == 4)
{
memoryWriteLong(value, sp);
}
if (N == 2)
{
memoryWriteWord(value, sp);
}
}
// pre-define these templates to prevent instantiation errors.
template<int Bytes, int Offset, typename... Args>
uint32_t StackFrame__(uint32_t sp, uint32_t &x, Args&&... args);
template<int Bytes, int Offset, typename... Args>
uint32_t StackFrame__(uint32_t sp, uint16_t &x, Args&&... args);
template<int Bytes, int Offset, typename... Args>
uint32_t StackFrame__(uint32_t sp, uint8_t &x, Args&&... args);
template<int Bytes, int Offset>
uint32_t StackFrame__(uint32_t sp);
template<int Bytes, int Offset>
uint32_t StackFrame__(uint32_t sp)
{
static_assert(Offset == 0, "Invalid Stack Size");
cpuSetAReg(7, sp + Bytes);
return sp + Bytes;
}
template<int Bytes, int Offset, typename... Args>
uint32_t StackFrame__(uint32_t sp, uint32_t &x, Args&&... args)
{
x = memoryReadLong(sp + Offset - 4);
return StackFrame__<Bytes, Offset - 4>(sp, std::forward<Args>(args)...);
}
template<int Bytes, int Offset, typename... Args>
uint32_t StackFrame__(uint32_t sp, uint16_t &x, Args&&... args)
{
x = memoryReadWord(sp + Offset - 2);
return StackFrame__<Bytes, Offset - 2>(sp, std::forward<Args>(args)...);
}
template<int Bytes, int Offset, typename... Args>
uint32_t StackFrame__(uint32_t sp, uint8_t &x, Args&&... args)
{
// byte pushes as 2 bytes with 1 garbage byte
x = memoryReadByte(sp + Offset - 2);
return StackFrame__<Bytes, Offset - 2>(sp, std::forward<Args>(args)...);
}
template<int Bytes, typename... Args>
uint32_t StackFrame(Args&&... args)
{
uint32_t sp = cpuGetAReg(7);
return StackFrame__<Bytes, Bytes>(sp, std::forward<Args>(args)...);
}
#endif