consistently use hidden visibility for cancellable syscall internals

in a few places, non-hidden symbols were referenced from asm in ways
that assumed ld-time binding. while these is no semantic reason these
symbols need to be hidden, fixing the references without making them
hidden was going to be ugly, and hidden reduces some bloat anyway.

in the asm files, .global/.hidden directives have been moved to the
top to unclutter the actual code.

arch/x32/src/syscall_cp_fixup.c

 #include <sys/syscall.h>
+
+#ifdef SHARED
+__attribute__((__visibility__("hidden")))
+#endif
 long __syscall_cp_internal(volatile void*, long long, long long, long long, long long,
                              long long, long long, long long);
 
@@ -8,6 +12,9 @@ struct __timespec_kernel { long long tv_sec; long long tv_nsec; };
 #define __fixup(X) do { if(X) X = (unsigned long) (&(struct __timespec_kernel) \
                    { .tv_sec = __tsc(X)->tv_sec, .tv_nsec = __tsc(X)->tv_nsec}); } while(0)
 
+#ifdef SHARED
+__attribute__((__visibility__("hidden")))
+#endif
 long __syscall_cp_asm (volatile void * foo, long long n, long long a1, long long a2, long long a3,
 	                     long long a4, long long a5, long long a6) {
 	switch (n) {

src/thread/aarch64/syscall_cp.s

@@ -4,10 +4,17 @@
 // syscall(nr, u, v, w, x, y, z)
 //         x8  x0 x1 x2 x3 x4 x5
 
+.global __cp_begin
+.hidden __cp_begin
+.global __cp_end
+.hidden __cp_end
+.global __cp_cancel
+.hidden __cp_cancel
+.hidden __cancel
 .global __syscall_cp_asm
+.hidden __syscall_cp_asm
 .type __syscall_cp_asm,%function
 __syscall_cp_asm:
-.global __cp_begin
 __cp_begin:
 	ldr w0,[x0]
 	cbnz w0,1f
@@ -19,7 +26,6 @@ __cp_begin:
 	mov x4,x6
 	mov x5,x7
 	svc 0
-.global __cp_end
 __cp_end:
 	ret
 

src/thread/arm/syscall_cp.s

+.global __cp_begin
+.hidden __cp_begin
+.global __cp_end
+.hidden __cp_end
+.global __cp_cancel
+.hidden __cp_cancel
+.hidden __cancel
 .global __syscall_cp_asm
+.hidden __syscall_cp_asm
 .type __syscall_cp_asm,%function
 __syscall_cp_asm:
 	mov ip,sp
 	stmfd sp!,{r4,r5,r6,r7,lr}
-.global __cp_begin
 __cp_begin:
 	ldr r0,[r0]
 	cmp r0,#0
@@ -13,13 +20,11 @@ __cp_begin:
 	mov r1,r3
 	ldmfd ip,{r2,r3,r4,r5,r6}
 	svc 0
-.global __cp_end
 __cp_end:
 	ldmfd sp!,{r4,r5,r6,r7,lr}
 	tst lr,#1
 	moveq pc,lr
 	bx lr
-.global __cp_cancel
 __cp_cancel:
 	ldmfd sp!,{r4,r5,r6,r7,lr}
 	b __cancel

src/thread/i386/syscall_cp.s

 .text
+.global __cp_begin
+.hidden __cp_begin
+.global __cp_end
+.hidden __cp_end
+.global __cp_cancel
+.hidden __cp_cancel
+.hidden __cancel
 .global __syscall_cp_asm
+.hidden __syscall_cp_asm
 .type   __syscall_cp_asm,@function
 __syscall_cp_asm:
 	mov 4(%esp),%ecx
@@ -7,7 +15,6 @@ __syscall_cp_asm:
 	pushl %esi
 	pushl %edi
 	pushl %ebp
-.global __cp_begin
 __cp_begin:
 	movl (%ecx),%eax
 	testl %eax,%eax
@@ -20,14 +27,12 @@ __cp_begin:
 	movl 44(%esp),%edi
 	movl 48(%esp),%ebp
 	int $128
-.global __cp_end
 __cp_end:
 	popl %ebp
 	popl %edi
 	popl %esi
 	popl %ebx
 	ret
-.global __cp_cancel
 __cp_cancel:
 	popl %ebp
 	popl %edi

src/thread/microblaze/syscall_cp.s

+.global __cp_begin
+.hidden __cp_begin
+.global __cp_end
+.hidden __cp_end
+.global __cp_cancel
+.hidden __cp_cancel
+.hidden __cancel
 .global __syscall_cp_asm
+.hidden __syscall_cp_asm
 .type   __syscall_cp_asm,@function
 __syscall_cp_asm:
-.global __cp_begin
 __cp_begin:
 	lwi     r5, r5, 0
-	bnei    r5, __cancel@PLT
+	bnei    r5, __cancel
 	addi    r12, r6, 0
 	add     r5, r7, r0
 	add     r6, r8, r0
@@ -13,7 +20,6 @@ __cp_begin:
 	lwi     r9, r1, 28
 	lwi     r10, r1, 32
 	brki    r14, 0x8
-.global __cp_end
 __cp_end:
 	rtsd    r15, 8
 	nop

src/thread/mips/syscall_cp.s

 .set    noreorder
 
+.global __cp_begin
+.hidden __cp_begin
+.global __cp_end
+.hidden __cp_end
+.global __cp_cancel
+.hidden __cp_cancel
+.hidden __cancel
 .global __syscall_cp_asm
+.hidden __syscall_cp_asm
 .type   __syscall_cp_asm,@function
 __syscall_cp_asm:
 	subu    $sp, $sp, 32
-.global __cp_begin
 __cp_begin:
 	lw      $4, 0($4)
 	bne     $4, $0, __cp_cancel
@@ -22,7 +29,6 @@ __cp_begin:
 	sw      $2, 28($sp)
 	lw      $2, 28($sp)
 	syscall
-.global __cp_end
 __cp_end:
 	beq     $7, $0, 1f
 	addu    $sp, $sp, 32
@@ -30,7 +36,6 @@ __cp_end:
 1:	jr      $ra
 	nop
 
-.global __cp_cancel
 __cp_cancel:
 	addu    $sp, $sp, 32
 	lw      $25, %call16(__cancel)($gp)

src/thread/or1k/syscall_cp.s

+.global __cp_begin
+.hidden __cp_begin
+.global __cp_end
+.hidden __cp_end
+.global __cp_cancel
+.hidden __cp_cancel
+.hidden __cancel
 .global __syscall_cp_asm
+.hidden __syscall_cp_asm
 .type   __syscall_cp_asm,@function
 __syscall_cp_asm:
-.global __cp_begin
 __cp_begin:
 	l.lwz	r3, 0(r3)
 	l.sfeqi	r3, 0
-	l.bnf	plt(__cancel)
+	l.bnf	__cancel
 	 l.ori	r11, r4, 0
 	l.ori	r3, r5, 0
 	l.ori	r4, r6, 0
@@ -14,7 +21,6 @@ __cp_begin:
 	l.lwz	r7, 0(r1)
 	l.lwz	r8, 4(r1)
 	l.sys	1
-.global __cp_end
 __cp_end:
 	l.jr	r9
 	 l.nop

src/thread/powerpc/syscall_cp.s

+.global __cp_begin
+.hidden __cp_begin
+.global __cp_end
+.hidden __cp_end
+.global __cp_cancel
+.hidden __cp_cancel
+.hidden __cancel
+.global __syscall_cp_asm
+.hidden __syscall_cp_asm
+
 #r0: volatile. may be modified during linkage.
 #r1: stack frame: 16 byte alignment.
 #r2: tls/thread pointer on pp32
@@ -16,11 +26,9 @@
 #the fields CR2,CR2,CR4 of the cond reg must be preserved
 #LR (link reg) shall contain the funcs return address
 	.text
-	.global __syscall_cp_asm
 	.type   __syscall_cp_asm,%function
 __syscall_cp_asm:
 	# at enter: r3 = pointer to self->cancel, r4: syscall no, r5: first arg, r6: 2nd, r7: 3rd, r8: 4th, r9: 5th, r10: 6th
-	.global __cp_begin
 __cp_begin:
 	# r3 holds first argument, its a pointer to self->cancel. 
 	# we must compare the dereferenced value with 0 and jump to __cancel if its not
@@ -42,7 +50,6 @@ __cp_begin:
 	mr      7, 9                  # arg5
 	mr      8, 10                  # arg6
 	sc
-	.global __cp_end
 __cp_end:
 	bnslr+ # return if no summary overflow. 
 	#else negate result.

src/thread/pthread_cancel.c

@@ -3,7 +3,13 @@
 #include "syscall.h"
 #include "libc.h"
 
-long __cancel()
+#ifdef SHARED
+#define hidden __attribute__((__visibility__("hidden")))
+#else
+#define hidden
+#endif
+
+hidden long __cancel()
 {
 	pthread_t self = __pthread_self();
 	if (self->canceldisable == PTHREAD_CANCEL_ENABLE || self->cancelasync)
@@ -16,12 +22,14 @@ long __cancel()
  * definition of __cp_cancel to undo those adjustments and call __cancel.
  * Otherwise, __cancel provides a definition for __cp_cancel. */
 
-weak_alias(__cancel, __cp_cancel);
+hidden weak_alias(__cancel, __cp_cancel);
 
+hidden
 long __syscall_cp_asm(volatile void *, syscall_arg_t,
                       syscall_arg_t, syscall_arg_t, syscall_arg_t,
                       syscall_arg_t, syscall_arg_t, syscall_arg_t);
 
+hidden
 long __syscall_cp_c(syscall_arg_t nr,
                     syscall_arg_t u, syscall_arg_t v, syscall_arg_t w,
                     syscall_arg_t x, syscall_arg_t y, syscall_arg_t z)
@@ -52,7 +60,7 @@ static void cancel_handler(int sig, siginfo_t *si, void *ctx)
 	pthread_t self = __pthread_self();
 	ucontext_t *uc = ctx;
 	const char *ip = ((char **)&uc->uc_mcontext)[CANCEL_REG_IP];
-	extern const char __cp_begin[1], __cp_end[1];
+	hidden extern const char __cp_begin[1], __cp_end[1];
 
 	a_barrier();
 	if (!self->cancel || self->canceldisable == PTHREAD_CANCEL_DISABLE) return;

src/thread/sh/syscall_cp.s

 .text
+.global __cp_begin
+.hidden __cp_begin
+.global __cp_end
+.hidden __cp_end
+.global __cp_cancel
+.hidden __cp_cancel
+.hidden __cancel
 .global __syscall_cp_asm
+.hidden __syscall_cp_asm
 .type   __syscall_cp_asm, @function
 __syscall_cp_asm:
 
-.global __cp_begin
 __cp_begin:
 	mov.l @r4, r4
 	tst   r4, r4
@@ -15,7 +22,7 @@ __cp_begin:
 1:
 
 .align 2
-L1:	.long __cancel@PLT-(1b-.)
+L1:	.long __cancel-(1b-.)
 
 2:	mov   r5, r3
 	mov   r6, r4
@@ -26,7 +33,6 @@ L1:	.long __cancel@PLT-(1b-.)
 	mov.l @(12,r15), r1
 	trapa #22
 
-.global __cp_end
 __cp_end:
 	! work around hardware bug
 	or   r0, r0

src/thread/x32/syscall_cp.s

 .text
+.global __cp_begin
+.hidden __cp_begin
+.global __cp_end
+.hidden __cp_end
+.global __cp_cancel
+.hidden __cp_cancel
+.hidden __cancel
 .global __syscall_cp_internal
+.hidden __syscall_cp_internal
 .type   __syscall_cp_internal,@function
 __syscall_cp_internal:
 
-.global __cp_begin
 __cp_begin:
 	mov (%rdi),%eax
 	test %eax,%eax
@@ -18,6 +25,5 @@ __cp_begin:
 	mov 16(%rsp),%r9
 	mov %r11,8(%rsp)
 	syscall
-.global __cp_end
 __cp_end:
 	ret

src/thread/x86_64/syscall_cp.s

 .text
+.global __cp_begin
+.hidden __cp_begin
+.global __cp_end
+.hidden __cp_end
+.global __cp_cancel
+.hidden __cp_cancel
+.hidden __cancel
 .global __syscall_cp_asm
+.hidden __syscall_cp_asm
 .type   __syscall_cp_asm,@function
 __syscall_cp_asm:
 
-.global __cp_begin
 __cp_begin:
 	mov (%rdi),%eax
 	test %eax,%eax
@@ -18,6 +25,5 @@ __cp_begin:
 	mov 16(%rsp),%r9
 	mov %r11,8(%rsp)
 	syscall
-.global __cp_end
 __cp_end:
 	ret