[PATCH,gcc/MIPS] Make loongson3a use fused madd.d

[Paul Hua]

Hi,

Loongson3a has 4 operand fused madd instrcution. This patch set
loongson3a use fused madd.d.



ChangeLog :

*** gcc/ChangeLog ***

2016-11-03 Chenghua Xu <paul.hua...@gmail.com>

    config/mips/
    * mips.h: Set loongson3a use fused madd.d.


Tested on loongson3a.


PS: I will soon submit some patches, how can i get a copyright assignment.

diff --git a/gcc/config/mips/mips.h b/gcc/config/mips/mips.h
index 81862a9..5076a2b 100644
--- a/gcc/config/mips/mips.h
+++ b/gcc/config/mips/mips.h
@@ -1056,11 +1056,11 @@ struct mips_cpu_info {
 
 /* ISA has 4 operand fused madd instructions of the form
    'd = [+-] (a * b [+-] c)'.  */
-#define ISA_HAS_FUSED_MADD4	TARGET_MIPS8000
+#define ISA_HAS_FUSED_MADD4	(TARGET_MIPS8000 || TARGET_LOONGSON_3A)
 
 /* ISA has 4 operand unfused madd instructions of the form
    'd = [+-] (a * b [+-] c)'.  */
-#define ISA_HAS_UNFUSED_MADD4	(ISA_HAS_FP4 && !TARGET_MIPS8000)
+#define ISA_HAS_UNFUSED_MADD4	(ISA_HAS_FP4 && !TARGET_MIPS8000 && !TARGET_LOONGSON_3A)
 
 /* ISA has 3 operand r6 fused madd instructions of the form
    'c = c [+-] (a * b)'.  */