user: implement mlibc as the libc, finally.

It's finally done..

Signed-off-by: kaguya <vpshinomiya@protonmail.com>

user/include/mlibc/options/internal/x86_64/setjmp.S

@@ -0,0 +1,60 @@
+
+.type __setjmp, "function"
+__setjmp:
+	mov %rbx, 0x00(%rdi)
+	mov %rbp, 0x08(%rdi)
+	mov %r12, 0x10(%rdi)
+	mov %r13, 0x18(%rdi)
+	mov %r14, 0x20(%rdi)
+	mov %r15, 0x28(%rdi)
+
+	lea 8(%rsp), %rax # rsp before return rip is pushed
+	mov %rax, 0x30(%rdi)
+	mov (%rsp), %rax # return rip
+	mov %rax, 0x38(%rdi)
+
+	test %rdx, %rdx
+	jnz 1f
+	xor %rax, %rax
+	ret
+
+1:
+	jmp __sigsetjmp
+
+.global setjmp
+.type setjmp, "function"
+.global _setjmp
+.type _setjmp, "function"
+setjmp:
+_setjmp:
+	xor %rdx, %rdx
+	jmp __setjmp
+
+.global sigsetjmp
+.type sigsetjmp, "function"
+sigsetjmp:
+	mov $1, %rdx
+	jmp __setjmp
+
+.global longjmp
+.type longjmp, "function"
+.global _longjmp
+.type _longjmp, "function"
+longjmp:
+_longjmp:
+	mov 0x00(%rdi), %rbx
+	mov 0x08(%rdi), %rbp
+	mov 0x10(%rdi), %r12
+	mov 0x18(%rdi), %r13
+	mov 0x20(%rdi), %r14
+	mov 0x28(%rdi), %r15
+
+	mov  %rsi, %rax
+	test %rax, %rax
+	jnz 1f
+	inc %rax
+1:
+	mov  0x30(%rdi), %rsp
+	jmp  *0x38(%rdi)
+.section .note.GNU-stack,"",%progbits
+