Changeset 219 for soft

Timestamp:

Oct 4, 2012, 10:56:18 AM (12 years ago)

Author:

meunier

Message:

Correction d'un bug dans _int_handler : on ne sauvegardait pas les registres HI et LO
(problématique si interruption reçue entre multu et mfhi par exemple)

File:

• soft/giet_vm/sys/giet.s (modified) (3 diffs)

soft/giet_vm/sys/giet.s

@@ -101 +101 @@
 
 _int_handler:
-    addiu   $29,    $29,    -23*4   /* stack space reservation (19 registers to
+    addiu   $29,    $29,    -25*4   /* stack space reservation (21 registers to
                                        save and 4 free words to call function) */
     .set noat
@@ -123 +123 @@
     sw      $25,    20*4($29)       /* save $25 */
     sw      $31,    21*4($29)       /* save $31 */
+    mflo    $26
+    sw      $26,    22*4($29)       /* save LO */
+    mfhi    $26
+    sw      $26,    23*4($29)       /* save HI */
     mfc0    $27,    $14
-    sw      $27,    22*4($29)       /* save EPC */
+    sw      $27,    24*4($29)       /* save EPC */
 
     la      $26,    _irq_demux
@@ -150 +154 @@
     lw      $25,    4*20($29)       /* restore $25 */
     lw      $31,    4*21($29)       /* restore $31 */
-    lw      $27,    4*22($29)       /* return address (EPC) */
-    addiu   $29,    $29,    23*4    /* restore stack pointer */
+    lw      $26,    4*22($29)
+    mtlo    $26                     /* restore LO */
+    lw      $26,    4*23($29)
+    mthi    $26                     /* restore HI */
+    lw      $27,    4*24($29)       /* return address (EPC) */
+    addiu   $29,    $29,    25*4    /* restore stack pointer */
     mtc0    $27,    $14             /* restore EPC */
     eret                            /* exit GIET */