Changeset c13ddac0 in rtems

Timestamp:

Apr 4, 2011, 4:44:55 PM (10 years ago)

Author:

Joel Sherrill <joel.sherrill@…>

Branches:

4.10

Children:

46604fcc

Parents:

619f97e

Message:

2011-04-04 Joel Sherrill <joel.sherrilL@…>

PR 1768/bsps

• shared/irq/irq_asm.S: The nbench benchmark highlighted the fact that we do not perform a cld before calling C code in the ISR. This was historically not a problem but gcc 4.3 changed the behavior. From ​http://gcc.gnu.org/gcc-4.3/changes.html

Location:

c/src/lib/libbsp/i386

Files:

• ChangeLog (modified) (1 diff)
• shared/irq/irq_asm.S (modified) (1 diff)

c/src/lib/libbsp/i386/ChangeLog

@@ +1 @@
+2011-04-04      Joel Sherrill <joel.sherrilL@OARcorp.com>
+
+        PR 1768/bsps
+        * shared/irq/irq_asm.S: The nbench benchmark highlighted the fact that
+        we do not perform a cld before calling C code in the ISR. This was
+        historically not a problem but gcc 4.3 changed the behavior. From
+        http://gcc.gnu.org/gcc-4.3/changes.html
+
 2011-02-02      Ralf Corsépius <ralf.corsepius@rtems.org>
 

c/src/lib/libbsp/i386/shared/irq/irq_asm.S

@@ -145 +145 @@
         incl      SYM (_ISR_Nest_level)     /* one nest level deeper */
         incl      SYM (_Thread_Dispatch_disable_level) /* disable multitasking */
+
+        /*
+         * GCC versions starting with 4.3 no longer place the cld
+         * instruction before string operations.  We  need to ensure
+         * it is set correctly for ISR handlers.
+         */
+        cld
 
         /*