[Qemu-devel] [PATCH][SPARC] mem_address_not_aligned trap for unaligned PC

[Aurelien Jarno <aurelien@aurel32.net>]

Hi all,

According to the SPARCv8 and SPARCv9 manuals, the jmpl, rett and return
instructions should generate a mem_address_not_aligned trap if either
of the low-order two bits of the target address is nonzero.

The patch below implements that.

Bye,
Aurelien


Index: target-sparc/cpu.h
===================================================================
RCS file: /sources/qemu/qemu/target-sparc/cpu.h,v
retrieving revision 1.32
diff -u -d -p -r1.32 cpu.h
--- target-sparc/cpu.h	1 Apr 2007 15:15:36 -0000	1.32
+++ target-sparc/cpu.h	1 Apr 2007 16:51:22 -0000
@@ -35,6 +35,7 @@
 #define TT_NFPU_INSN 0x04
 #define TT_WIN_OVF  0x05
 #define TT_WIN_UNF  0x06 
+#define TT_UNALIGNED 0x07 
 #define TT_FP_EXCP  0x08
 #define TT_DFAULT   0x09
 #define TT_TOVF     0x0a
@@ -55,6 +56,7 @@
 #define TT_DFAULT   0x30
 #define TT_DMISS    0x31
 #define TT_DPROT    0x32
+#define TT_UNALIGNED 0x34
 #define TT_PRIV_ACT 0x37
 #define TT_EXTINT   0x40
 #define TT_SPILL    0x80
Index: target-sparc/op.c
===================================================================
RCS file: /sources/qemu/qemu/target-sparc/op.c,v
retrieving revision 1.27
diff -u -d -p -r1.27 op.c
--- target-sparc/op.c	1 Apr 2007 15:38:17 -0000	1.27
+++ target-sparc/op.c	1 Apr 2007 17:01:15 -0000
@@ -1486,7 +1486,10 @@ void OPPROTO op_movl_npc_im(void)
 
 void OPPROTO op_movl_npc_T0(void)
 {
-    env->npc = T0;
+    if (T0 & 0x3)
+	raise_exception(TT_UNALIGNED);
+    else
+	env->npc = T0;
 }
 
 void OPPROTO op_mov_pc_npc(void)

-- 
  .''`.  Aurelien Jarno	            | GPG: 1024D/F1BCDB73
 : :' :  Debian developer           | Electrical Engineer
 `. `'   aurel32@debian.org         | aurelien@aurel32.net
   `-    people.debian.org/~aurel32 | www.aurel32.net