nds32: add NPTL/TLS, *context function, libm changes and code cleanup

This commit includes following features.
1. Support NPTL/TLS
2. Add libm function which is used to handle FP rounding and excpetions
   (ex: fclrexcpt,fedisblxcpti,feenablxcpt... )
3. Add *context function for operating user context
   (ex: setcontext,getcontext,makecontext... )
4. Change the return flow from signal handler
5. Cleanup of old code

The testsuite only has 2 errors, tst-cpuclock1 and tst-cputimer1,
which are related to timing accuracy. (math and locale tests are disabled)

Signed-off-by: Vincent Ren-Wei Chen <vincentc@andestech.com>

1 files changed, 85 insertions, 29 deletions

diff --git a/libc/sysdeps/linux/nds32/vfork.S b/libc/sysdeps/linux/nds32/vfork.S
index c955359fb..ac3fa30fd 100644
--- a/libc/sysdeps/linux/nds32/vfork.S
+++ b/libc/sysdeps/linux/nds32/vfork.S
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2016 Andes Technology, Inc.
+ * Copyright (C) 2016-2017 Andes Technology, Inc.
  * Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
  */
 
@@ -21,24 +21,36 @@
    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
    02111-1307 USA.  */
 
-#include <sys/syscall.h>
 #include <sysdep.h>
-
 #define _ERRNO_H    1
+#include <bits/errno.h>
+
+#ifndef SAVE_PID
+#define SAVE_PID
+#endif
 
+#ifndef RESTORE_PID
+#define RESTORE_PID
+#endif
 /* Clone the calling process, but without copying the whole address space.
    The calling process is suspended until the new process exits or is
    replaced by a call to `execve'.  Return -1 for errors, 0 to the new process,
    and the process ID of the new process to the old process.  */
 
+
 ENTRY (__vfork)
 #ifdef PIC
 .pic
 #endif
 
 #ifdef __NR_vfork
-
+# ifdef SAVE_PID
+    SAVE_PID
+# endif
     syscall __NR_vfork
+# ifdef RESTORE_PID
+    RESTORE_PID
+# endif
     bltz $r0, 2f
 1:
     ret
@@ -46,42 +58,86 @@ ENTRY (__vfork)
     sltsi $r1, $r0, -4096
     bnez $r1, 1b;
 
+# ifdef __ASSUME_VFORK_SYSCALL
 #  ifdef PIC
-	#ifdef __NDS32_N1213_43U1H__
-		! save lp
-		addi	$r2,	$lp,	0
-
-		! set r1 as gp
-		jal	1b
-		sethi	$r1,	hi20(_GLOBAL_OFFSET_TABLE_)
-		ori	$r1,	$r1,	lo12(_GLOBAL_OFFSET_TABLE_+4)
-		add	$r1,	$lp,	$r1
-
-		! restore lp
-		addi	$lp,	$r2,	0
-	#else
-		! set r1 as gp
-		mfusr $r15, $PC
-		sethi	$r1,	hi20(_GLOBAL_OFFSET_TABLE_+4)
-		ori	$r1,	$r1,	lo12(_GLOBAL_OFFSET_TABLE_+8)
-		add	$r1,	$r1,	$r15
-	#endif
+	pushm	$gp,	$lp
+	cfi_adjust_cfa_offset(8)
+	cfi_rel_offset(gp, 0)
+	cfi_rel_offset(lp, 4)
+	mfusr 	$r15, 	$PC
+	sethi	$gp,	hi20(_GLOBAL_OFFSET_TABLE_+4)
+	ori	$gp,	$gp,	lo12(_GLOBAL_OFFSET_TABLE_+8)
+	add	$gp,	$gp,	$r15
 
 	! r15=C_SYMBOL_NAME(__syscall_error)@PLT
-	sethi $r15, hi20(C_SYMBOL_NAME(__syscall_error)@PLT)
+	sethi	$r15, 	hi20(C_SYMBOL_NAME(__syscall_error)@PLT)
 	ori	$r15,	$r15, lo12(C_SYMBOL_NAME(__syscall_error)@PLT)
-	add	$r15, $r15, $r1
+	add	$r15, 	$r15, 	$gp
 
 	! jump to SYSCALL_ERROR
-	jr		$r15
+	jral		$r15
+	popm	$gp,	$lp
+	cfi_adjust_cfa_offset(-8)
+	cfi_restore(lp)
+	cfi_restore(gp)
+	ret
 #  else
 	j C_SYMBOL_NAME(__syscall_error)
 #  endif
+# else
+    /* Check if vfork syscall is known at all. */
+	li $r1, -ENOSYS
+	beq	$r0, $r1, 1f
+
+# ifdef PIC
+3:
+	pushm	$gp,	$lp
+	cfi_adjust_cfa_offset(8)
+	cfi_rel_offset(gp, 0)
+	cfi_rel_offset(lp, 4)
+	mfusr	$r15,   $PC
+	sethi   $gp,    hi20(_GLOBAL_OFFSET_TABLE_+4)
+	ori     $gp,    $gp,    lo12(_GLOBAL_OFFSET_TABLE_+8)
+	add     $gp,    $gp,    $r15
+
+	! r15=C_SYMBOL_NAME(__syscall_error)@PLT
+	sethi	$r15,	hi20(C_SYMBOL_NAME(__syscall_error)@PLT)
+	ori     $r15,	$r15, lo12(C_SYMBOL_NAME(__syscall_error)@PLT)
+	add     $r15,	$r15, 	$gp
+
+	! jump to SYSCALL_ERROR
+	jral		$r15
+	popm	$gp,	$lp
+	cfi_adjust_cfa_offset(-8)
+	cfi_restore(lp)
+	cfi_restore(gp)
+	ret
+# else
+        j C_SYMBOL_NAME(__syscall_error)
+# endif
+1:
+# endif
+#endif
+
+#ifndef __ASSUME_VFORK_SYSCALL
+    /* If we don't have vfork, fork is close enough. */
+	syscall __NR_fork
+	bgez $r0, 1f
+	sltsi $r1, $r0, -4096
+	bnez	$r1, 1f
+
+# ifdef PIC
+        b       3b
+# else
+        j C_SYMBOL_NAME(__syscall_error)
+# endif
+1:
+    ret
 
-#else
-# error "__NR_vfork not available"
+#elif !defined __NR_vfork
+# error "__NR_vfork not available and __ASSUME_VFORK_SYSCALL defined"
 #endif
 
 PSEUDO_END (__vfork)
 weak_alias (__vfork, vfork)
-libc_hidden_def(vfork)
+libc_hidden_def (vfork)