Port musl to x86-64. One giant commit!

src/thread/x86_64/__set_thread_area.s

@@ -0,0 +1,15 @@
+/* Copyright 2011 Nicholas J. Kain, licensed GNU LGPL 2.1 or later */
+.text
+.global __set_thread_area
+.type   __set_thread_area,%function
+__set_thread_area:
+        push %rbx               /* save x86_64 abi clobbered registers */
+        push %r11
+        mov %rdi,%rsi           /* shift for syscall */
+        movl $0x1002,%edi       /* SET_FS register */
+        movl $158,%eax          /* set fs segment to */
+        syscall                 /* arch_prctl(SET_FS, arg)*/
+        pop %r11                /* restore clobbered registers */
+        pop %rbx
+	ret
+.size __set_thread_area,.-__set_thread_area

src/thread/x86_64/__unmapself.s

@@ -0,0 +1,24 @@
+/* Copyright 2011 Nicholas J. Kain, licensed GNU LGPL 2.1 or later */
+.text
+.global __unmapself
+.type   __unmapself,%function
+__unmapself:
+	call 1f         /* glibc ABI compat */
+	.long -1
+	.long -1
+1:      push %rsi       /* save arg2 for munmap */
+	push %rdx       /* save arg3 for munmap */
+	mov %rdi,%rsi   /* rt_sigprocmask() args: move arg1 to rsi */
+	xor %rdi,%rdi
+	xor %rdx,%rdx
+	movq $8,%r10
+	movl $14,%eax   /* __NR_rt_sigprocmask */
+	syscall         /* call rt_sigprocmask(0,arg1,0,8) */
+	pop %rsi        /* munmap() args: reload from stack */
+	pop %rdi
+	movl $11,%eax   /* __NR_munmap */
+	syscall         /* munmap(arg2,arg3) */
+	xor %rdi,%rdi   /* exit() args: always return success */
+	movl $60,%eax   /* __NR_exit */
+	syscall         /* exit(0) */
+.size __unmapself,.-__unmapself

src/thread/x86_64/clone.s

@@ -0,0 +1,22 @@
+/* Copyright 2011 Nicholas J. Kain, licensed GNU LGPL 2.1 or later */
+.text
+.global __uniclone
+.type   __uniclone,%function
+/* rdi = child_stack, rsi = start, rdx = pthread_struct */
+__uniclone:
+        subq    $16,%rdi        /* grow child_stack */
+        mov     %rsi,8(%rdi)    /* push start onto child_stack as return ptr */
+        mov     %rdx,0(%rdi)    /* push pthread_struct onto child_stack */
+        mov     %rdx,%r8        /* r8 = tls */
+        mov     %rdi,%rsi       /* rsi = child_stack */
+        leaq    40(%rdx),%r10   /* r10 = child_id */
+        movl    $56,%eax        /* clone syscall number */
+        movl    $0x7d0f00,%edi  /* rdi = flags */
+        mov     %r10,%rdx       /* rdx = parent_id */
+	syscall                 /* clone(flags, child_stack, parent_id,
+	                         *       child_id, tls) */
+	test	%rax,%rax
+	jnz	1f              /* if we're in the parent -> goto 1f */
+        pop     %rdi            /* restore pthread_struct from child stack */
+1:      ret
+.size __uniclone,.-__uniclone