src/arch/amd64/fpu.c


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#include <fpu.h>
#include <stddef.h>
#include <stdint.h>
#include <lib.h>

void enable_fpu(void) {
	size_t cr4;
	uint16_t cw = 0x37F;
	__asm__ volatile ("mov %%cr4, %0" : "=r"(cr4));
	cr4 |= 0x200;
	__asm__ volatile ("mov %0, %%cr4" :: "r"(cr4));
	__asm__ volatile("fldcw %0" :: "m"(cw));
}