xtensa: support call0 ABI

Most changes are mechanical replacement of 'retw' instruction with
'abi_ret' macro, defined to 'retw' or 'ret' according to ABI.
Assembly code that makes calls is duplicated for call0 ABI with changed
register numbers for parameters/return value and call instruction.
'entry' instructions are replaced with 'abi_entry' macro.

More interesting changes:
- non-leaf assembly functions (e.g. _dl_tlsdesc_dynamic,
  _dl_linux_resolve, SYSCALL_ERROR_HANDLER, PSEUDO) now need to preserve
  registers around intermediate calls they make, use temporary stack
  frame for that;
- setjmp/longjmp only need to save and restore return address, stack
  pointer and callee-saved registers in the jmpbuf;
- __clone and syscall functions had hardcoded offsets to parameter
  passed on stack, on call0 ABI they don't need stack frame, so the
  offset is different. Replace these offsets with FRAMESIZE macro.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

1 files changed, 4 insertions, 9 deletions

diff --git a/libpthread/nptl/sysdeps/xtensa/pthread_spin_trylock.S b/libpthread/nptl/sysdeps/xtensa/pthread_spin_trylock.S
index a736b010f..4742bdb1c 100644
--- a/libpthread/nptl/sysdeps/xtensa/pthread_spin_trylock.S
+++ b/libpthread/nptl/sysdeps/xtensa/pthread_spin_trylock.S
@@ -18,14 +18,10 @@
 
 #define _ERRNO_H 1
 #include <bits/errno.h>
+#include <sysdep.h>
 
 	.text
-	.align 4
-
-	.globl pthread_spin_trylock
-pthread_spin_trylock:
-
-	entry	a1, 16
+ENTRY (pthread_spin_trylock)
 
 	movi	a3, 0
 	wsr 	a3, scompare1
@@ -34,7 +30,6 @@ pthread_spin_trylock:
 	movi	a2, EBUSY
 	moveqz	a2, a3, a3
 
-	retw
+	abi_ret
 
-	.type pthread_spin_trylock, @function
-	.size pthread_spin_trylock, .-pthread_spin_trylock
+END (pthread_spin_trylock)