Port recent Android changes to mips64el

* exec/config-mips.m4.in (DADDI2, DADDI3): Disable at-clobbering
by assembler macros expressly.

* exec/loader-mips64el.s: Adapt from loader-mipsel.s.

* exec/configure.ac (exec_cv_as_daddi): Properly escape reg
names.

* exec/exec.c (struct exec_jump_command, exec_0): Don't define
or set `fpu_mode' if __LP64__.

* exec/exec.h (struct exec_tracee): New field `callno'.

* exec/trace.c (process_system_call): Always record the current
system call number in TRACEE lest it should be required once it
has been overwritten upon the syscall's completion.
(seccomp_system_call): Likewise.
(after_fork): Clear `tracee->callno'.

Author: Po Lu

exec/config-mips.m4.in

@@ -38,7 +38,11 @@ define(`RESTORE', `ifelse(`@MIPS_N32@',`yes',`	nop',`	addi	$sp, 32')')
 define(`FP', `ifelse(`@MIPS_N32@',`yes',`$s8',`$fp')')
 
 dnl For mips64.  Some assemblers don't want to assemble `daddi'.
-define(`DADDI2', `ifelse(`@DADDI_BROKEN@',`yes',`	li	$at, $2
-dadd		 $1, $1, $at',`	daddi	$1, $2')')
-define(`DADDI3', `ifelse(`@DADDI_BROKEN@',`yes',`	li	$at, $3
-dadd		 $1, $2, $at',`	daddi	$1, $2, $3')')
+define(`DADDI2', `ifelse(`@DADDI_BROKEN@',`yes',`.set noat
+li	$at, $2
+dadd	$1, $1, $at
+.set at',`	daddi	$1, $2')')
+define(`DADDI3', `ifelse(`@DADDI_BROKEN@',`yes',`.set noat
+li	$at, $3
+dadd	$1, $2, $at
+.set at',`	daddi	$1, $2, $3')')

exec/configure.ac

@@ -455,12 +455,12 @@ AS_CASE([$host], [x86_64-*linux*],
       .section text
       .global __start
 __start:
-	li	$t0, 0
-	li	$t1, 0
-	daddi	$t0, $t1, 1
-	daddi	$t0, $t1, -1
-	daddi	$t0, -1
-	daddi	$t0, 1
+	li	\$t0, 0
+	li	\$t1, 0
+	daddi	\$t0, \$t1, 1
+	daddi	\$t0, \$t1, -1
+	daddi	\$t0, -1
+	daddi	\$t0, 1
 
 _ACEOF
       $AS $ASFLAGS conftest.s -o conftest.$OBJEXT \

exec/exec.c

@@ -231,10 +231,10 @@ struct exec_jump_command
   /* The value of AT_BASE inside the aux vector.  */
   USER_WORD at_base;
 
-#if defined __mips__
+#if defined __mips__ && !defined __LP64__
   /* The FPU mode to apply.  Not used when !MIPS_NABI.  */
   USER_WORD fpu_mode;
-#endif /* defined __mips__ */
+#endif /* defined __mips__ && !defined __LP64__ */
 };
 
 
@@ -918,6 +918,7 @@ exec_0 (char *name, struct exec_tracee *tracee,
   USER_WORD header_offset;
   USER_WORD name_len, aligned_len;
   struct exec_jump_command jump;
+  /* This also encompasses !__LP64__.  */
 #if defined __mips__ && !defined MIPS_NABI
   int fpu_mode;
 #endif /* defined __mips__ && !defined MIPS_NABI */
@@ -1130,9 +1131,9 @@ exec_0 (char *name, struct exec_tracee *tracee,
     fpu_mode = FP_FRE;
 
   jump.fpu_mode = fpu_mode;
-#elif defined __mips__
+#elif defined __mips__ && !defined __LP64__
   jump.fpu_mode = 0;
-#endif /* defined __mips__ && !defined MIPS_NABI */
+#endif /* defined __mips__ && defined MIPS_NABI && !defined __LP64__ */
 
   /* The offset used for at_phdr should be that of the first
      mapping.  */

exec/exec.h

@@ -152,6 +152,10 @@ struct exec_tracee
      completion.  */
   USER_WORD sp;
 
+  /* ID of the system call that is pending completion.  This value is
+     not available as the call number is overwritten on success.  */
+  USER_WORD callno;
+
   /* Name of the executable being run.  */
   char *exec_file;