gplib/include/gp/system/platforms/gcc-x86_64.hpp

#pragma once

#include "gp/containers/buffer.hpp"

#include <cstdint>

#define no_inline_decl(a)  __attribute__((noinline)) a

namespace gp{
	namespace system {
		namespace specifics {
			struct platform_data {
				platform_data() = default;
				
				platform_data(gp::buffer<char> stack_str)
				: stack_ptr((stack_str.end()-16).data)
				, base_ptr(stack_ptr)
				{}

				uint64_t rbx, r12, r13, r14, r15;

				void* stack_ptr;
				void* base_ptr;

				void pull() __attribute__((always_inline))
				{
					__asm__ __volatile__(
						"movq %%rsp, %0\n"
						"movq %%rbp, %1\n" 
						"movq %%rbx, %2\n" 
						"movq %%r12, %3\n" 
						"movq %%r13, %4\n" 
						"movq %%r14, %5\n" 
						"movq %%r15, %6\n" 
						: "=m"(stack_ptr)
						, "=m"(base_ptr)
						, "=m"(rbx)
						, "=m"(r12)
						, "=m"(r13)
						, "=m"(r14)
						, "=m"(r15)
					);
				}

				void* push(void* location)  __attribute__((always_inline))
				{
					volatile void* volatile tmp = static_cast<char*>(stack_ptr) - sizeof(void*);
					*static_cast<volatile void* volatile * volatile>(tmp) = location;
					__asm__ __volatile__(
						"movq %1, %%rsp\n"
						"movq %2, %%rbp\n"
						"movq %3, %%rbx\n"
						"movq %4, %%r12\n"
						"movq %5, %%r13\n"
						"movq %6, %%r14\n"
						"movq %7, %%r15\n"
						"popq %0\n"
						: "+r"(location)
						: "m"(tmp)
						, "m"(base_ptr)
						, "m"(rbx)
						, "m"(r12)
						, "m"(r13)
						, "m"(r14)
						, "m"(r15)
						: "memory"
					);
					return location;
				}
			};
		}
	}
}