[PATCH-v3] Generate more efficient memory barriers for LEON3

[Daniel Cederman]

ChangeLog:

2014-07-11  Daniel Cederman  <ceder...@gaisler.com>

gcc/config/sparc/
    * sync.md: Generate more efficient memory barriers for LEON3 

---
 gcc/config/sparc/sync.md |   10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/gcc/config/sparc/sync.md b/gcc/config/sparc/sync.md
index e6e237f..98ac0d3 100644
--- a/gcc/config/sparc/sync.md
+++ b/gcc/config/sparc/sync.md
@@ -64,11 +64,19 @@
   "stbar"
   [(set_attr "type" "multi")])
 
+;; For LEON3, STB has the effect of membar #StoreLoad.
+(define_insn "*membar_storeload_leon3"
+  [(set (match_operand:BLK 0 "" "")
+       (unspec:BLK [(match_dup 0) (const_int 2)] UNSPEC_MEMBAR))]
+  "TARGET_LEON3"
+  "stb\t%%g0, [%%sp-1]"
+  [(set_attr "type" "store")])
+
 ;; For V8, LDSTUB has the effect of membar #StoreLoad.
 (define_insn "*membar_storeload"
   [(set (match_operand:BLK 0 "" "")
        (unspec:BLK [(match_dup 0) (const_int 2)] UNSPEC_MEMBAR))]
-  "TARGET_V8"
+  "TARGET_V8 && !TARGET_LEON3"
   "ldstub\t[%%sp-1], %%g0"
   [(set_attr "type" "multi")])
 
-- 
1.7.9.5