[src/trunk]: src/sys/arch On second thought do not use bit 13 as a flag for s...

[martin <martin%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/9c5b423f1e38
branches:  trunk
changeset: 763611:9c5b423f1e38
user:      martin <martin%NetBSD.org@localhost>
date:      Sun Mar 27 18:47:08 2011 +0000

description:
On second thought do not use bit 13 as a flag for syscall numbers, userland
typically sets those from a 13bit signed integer immediate field in the
instruction, so would need to jump through hoops (ok, small hoops) to
avoid sign extension.
Use a combination of the existing syscall flags instead.

diffstat:

 sys/arch/sparc/include/trap.h      |   4 ++--
 sys/arch/sparc/sparc/syscall.c     |  10 ++++++----
 sys/arch/sparc64/include/trap.h    |   4 ++--
 sys/arch/sparc64/sparc64/syscall.c |   7 ++++---
 4 files changed, 14 insertions(+), 11 deletions(-)

diffs (102 lines):

diff -r d8c4cff8aef3 -r 9c5b423f1e38 sys/arch/sparc/include/trap.h
--- a/sys/arch/sparc/include/trap.h     Sun Mar 27 17:15:17 2011 +0000
+++ b/sys/arch/sparc/include/trap.h     Sun Mar 27 18:47:08 2011 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: trap.h,v 1.17 2011/03/23 20:41:30 martin Exp $ */
+/*     $NetBSD: trap.h,v 1.18 2011/03/27 18:47:08 martin Exp $ */
 
 /*
  * Copyright (c) 1992, 1993
@@ -131,7 +131,7 @@
 /* flags to system call (flags in %g1 along with syscall number) */
 #define        SYSCALL_G2RFLAG 0x400   /* on success, return to %g2 rather than npc */
 #define        SYSCALL_G7RFLAG 0x800   /* use %g7 as above (deprecated) */
-#define        SYSCALL_G5RFLAG 0x1000  /* use %g5 as above (only ABI compatible way) */
+#define        SYSCALL_G5RFLAG 0xc00   /* use %g5 as above (only ABI compatible way) */
 
 /*
  * `software trap' macros to keep people happy (sparc v8 manual says not
diff -r d8c4cff8aef3 -r 9c5b423f1e38 sys/arch/sparc/sparc/syscall.c
--- a/sys/arch/sparc/sparc/syscall.c    Sun Mar 27 17:15:17 2011 +0000
+++ b/sys/arch/sparc/sparc/syscall.c    Sun Mar 27 18:47:08 2011 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: syscall.c,v 1.24 2011/03/23 20:41:31 martin Exp $ */
+/*     $NetBSD: syscall.c,v 1.25 2011/03/27 18:47:09 martin Exp $ */
 
 /*
  * Copyright (c) 1996
@@ -49,7 +49,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: syscall.c,v 1.24 2011/03/23 20:41:31 martin Exp $");
+__KERNEL_RCSID(0, "$NetBSD: syscall.c,v 1.25 2011/03/27 18:47:09 martin Exp $");
 
 #include "opt_sparc_arch.h"
 #include "opt_multiprocessor.h"
@@ -250,7 +250,8 @@
                tf->tf_out[1] = rval.o[1];
                if (new) {
                        /* jmp %g5, (or %g2 or %g7, deprecated) on success */
-                       if (new & SYSCALL_G5RFLAG)
+                       if (__predict_true((new & SYSCALL_G5RFLAG)
+                                               == SYSCALL_G5RFLAG))
                                i = tf->tf_global[5];
                        else if (new & SYSCALL_G2RFLAG)
                                i = tf->tf_global[2];
@@ -340,7 +341,8 @@
                tf->tf_out[1] = rval.o[1];
                if (new) {
                        /* jmp %g5, (or %g2 or %g7, deprecated) on success */
-                       if (new & SYSCALL_G5RFLAG)
+                       if (__predict_true((new & SYSCALL_G5RFLAG) ==
+                                       SYSCALL_G5RFLAG))
                                i = tf->tf_global[5];
                        else if (new & SYSCALL_G2RFLAG)
                                i = tf->tf_global[2];
diff -r d8c4cff8aef3 -r 9c5b423f1e38 sys/arch/sparc64/include/trap.h
--- a/sys/arch/sparc64/include/trap.h   Sun Mar 27 17:15:17 2011 +0000
+++ b/sys/arch/sparc64/include/trap.h   Sun Mar 27 18:47:08 2011 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: trap.h,v 1.8 2011/03/23 20:41:31 martin Exp $ */
+/*     $NetBSD: trap.h,v 1.9 2011/03/27 18:47:09 martin Exp $ */
 
 /*
  * Copyright (c) 1996-1999 Eduardo Horvath
@@ -142,7 +142,7 @@
 /* flags to system call (flags in %g1 along with syscall number) */
 #define        SYSCALL_G2RFLAG 0x400   /* on success, return to %g2 rather than npc */
 #define        SYSCALL_G7RFLAG 0x800   /* use %g7 as above (deprecated) */
-#define        SYSCALL_G5RFLAG 0x1000  /* use %g5 as above (only ABI compatible way) */
+#define        SYSCALL_G5RFLAG 0xc00   /* use %g5 as above (only ABI compatible way) */
 
 /*
  * `software trap' macros to keep people happy (sparc v8 manual says not
diff -r d8c4cff8aef3 -r 9c5b423f1e38 sys/arch/sparc64/sparc64/syscall.c
--- a/sys/arch/sparc64/sparc64/syscall.c        Sun Mar 27 17:15:17 2011 +0000
+++ b/sys/arch/sparc64/sparc64/syscall.c        Sun Mar 27 18:47:08 2011 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: syscall.c,v 1.38 2011/03/23 20:41:31 martin Exp $ */
+/*     $NetBSD: syscall.c,v 1.39 2011/03/27 18:47:09 martin Exp $ */
 
 /*-
  * Copyright (c) 2005 The NetBSD Foundation, Inc.
@@ -79,7 +79,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: syscall.c,v 1.38 2011/03/23 20:41:31 martin Exp $");
+__KERNEL_RCSID(0, "$NetBSD: syscall.c,v 1.39 2011/03/27 18:47:09 martin Exp $");
 
 #include "opt_sa.h"
 
@@ -130,7 +130,8 @@
        int new = *code & (SYSCALL_G7RFLAG|SYSCALL_G2RFLAG|SYSCALL_G5RFLAG);
        *code &= ~(SYSCALL_G7RFLAG|SYSCALL_G2RFLAG|SYSCALL_G5RFLAG);
        if (new) {
-               if (new & SYSCALL_G5RFLAG)
+               /* note that G5RFLAG is multiple bits! */
+               if (__predict_true((new & SYSCALL_G5RFLAG) == SYSCALL_G5RFLAG))
                        tf->tf_pc = tf->tf_global[5];
                else if (new & SYSCALL_G7RFLAG)
                        tf->tf_pc = tf->tf_global[7];