[PATCH 5/7] [ARC] Use ACCL, ACCH registers whenever they are available.

[Claudiu Zissulescu]

gcc/
2016-12-09  Claudiu Zissulescu  <claz...@synopsys.com>

        * config/arc/arc.c (arc_conditional_register_usage): Use ACCL,
        ACCH registers whenever they are available.
---
 gcc/config/arc/arc.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/gcc/config/arc/arc.c b/gcc/config/arc/arc.c
index f820622..73d72c68 100644
--- a/gcc/config/arc/arc.c
+++ b/gcc/config/arc/arc.c
@@ -1588,6 +1588,15 @@ arc_conditional_register_usage (void)
     SET_HARD_REG_BIT (reg_class_contents[WRITABLE_CORE_REGS], ACCH_REGNO);
     SET_HARD_REG_BIT (reg_class_contents[CHEAP_CORE_REGS], ACCL_REGNO);
     SET_HARD_REG_BIT (reg_class_contents[CHEAP_CORE_REGS], ACCH_REGNO);
+    SET_HARD_REG_BIT (reg_class_contents[GENERAL_REGS], ACCL_REGNO);
+    SET_HARD_REG_BIT (reg_class_contents[GENERAL_REGS], ACCH_REGNO);
+    SET_HARD_REG_BIT (reg_class_contents[MPY_WRITABLE_CORE_REGS], ACCL_REGNO);
+    SET_HARD_REG_BIT (reg_class_contents[MPY_WRITABLE_CORE_REGS], ACCH_REGNO);
+
+     /* Allow the compiler to freely use them.  */
+    fixed_regs[ACCL_REGNO] = 0;
+    fixed_regs[ACCH_REGNO] = 0;
+
     arc_hard_regno_mode_ok[ACC_REG_FIRST] = D_MODES;
   }
 }
-- 
1.9.1