[ARC] Enable indexed loads for elf targers.

Enable indexed loads only for elf target, as the linux ones need more testing.

gcc/
2017-02-28  Claudiu Zissulescu  <claziss@synopsys.com>

	* config/arc/arc.opt (mindexed-loads): Use initial value
	TARGET_INDEXED_LOADS_DEFAULT.
	(mauto-modify-reg): Use initial value
	TARGET_AUTO_MODIFY_REG_DEFAULT.
	* config/arc/elf.h (TARGET_INDEXED_LOADS_DEFAULT): Define.
	(TARGET_AUTO_MODIFY_REG_DEFAULT): Likewise.
	* config/arc/linux.h (TARGET_INDEXED_LOADS_DEFAULT): Define.
	(TARGET_AUTO_MODIFY_REG_DEFAULT): Likewise.

From-SVN: r250274

gcc/ChangeLog

+2017-07-17  Claudiu Zissulescu  <claziss@synopsys.com>
+
+	* config/arc/arc.opt (mindexed-loads): Use initial value
+	TARGET_INDEXED_LOADS_DEFAULT.
+	(mauto-modify-reg): Use initial value
+	TARGET_AUTO_MODIFY_REG_DEFAULT.
+	* config/arc/elf.h (TARGET_INDEXED_LOADS_DEFAULT): Define.
+	(TARGET_AUTO_MODIFY_REG_DEFAULT): Likewise.
+	* config/arc/linux.h (TARGET_INDEXED_LOADS_DEFAULT): Define.
+	(TARGET_AUTO_MODIFY_REG_DEFAULT): Likewise.
+
 2017-07-17  Martin Liska  <mliska@suse.cz>
 
 	PR sanitizer/81302

gcc/config/arc/arc.opt

@@ -270,11 +270,11 @@ Target RejectNegative Var(arc_tune, TUNE_ARC700_4_2_XMAC)
 Tune for ARC700 R4.2 Cpu with XMAC block.
 
 mindexed-loads
-Target Var(TARGET_INDEXED_LOADS)
+Target Var(TARGET_INDEXED_LOADS) Init(TARGET_INDEXED_LOADS_DEFAULT)
 Enable the use of indexed loads.
 
 mauto-modify-reg
-Target Var(TARGET_AUTO_MODIFY_REG)
+Target Var(TARGET_AUTO_MODIFY_REG) Init(TARGET_AUTO_MODIFY_REG_DEFAULT)
 Enable the use of pre/post modify with register displacement.
 
 mmul32x16

gcc/config/arc/elf.h

@@ -58,3 +58,11 @@ along with GCC; see the file COPYING3.  If not see
 /* Bare-metal toolchains do not need a thread pointer register.  */
 #undef TARGET_ARC_TP_REGNO_DEFAULT
 #define TARGET_ARC_TP_REGNO_DEFAULT -1
+
+/* Indexed loads are default.  */
+#undef TARGET_INDEXED_LOADS_DEFAULT
+#define TARGET_INDEXED_LOADS_DEFAULT 1
+
+/* Pre/post modify with register displacement are default.  */
+#undef TARGET_AUTO_MODIFY_REG_DEFAULT
+#define TARGET_AUTO_MODIFY_REG_DEFAULT 1

gcc/config/arc/linux.h

@@ -83,3 +83,11 @@ along with GCC; see the file COPYING3.  If not see
 #define SUBTARGET_CPP_SPEC "\
    %{pthread:-D_REENTRANT} \
 "
+
+/* Indexed loads are default off.  */
+#undef TARGET_INDEXED_LOADS_DEFAULT
+#define TARGET_INDEXED_LOADS_DEFAULT 0
+
+/* Pre/post modify with register displacement are default off.  */
+#undef TARGET_AUTO_MODIFY_REG_DEFAULT
+#define TARGET_AUTO_MODIFY_REG_DEFAULT 0