[ARC] Add ARCv2 core3 tune option.

ARCv2 Core3 cpus are comming with dbnz support. Add this feature on
the tune option.

gcc/
2018-01-26  Claudiu Zissulescu  <claziss@synopsys.com>

        * config/arc/arc-arch.h (arc_tune_attr): Add ARC_TUNE_CORE_3.
        * config/arc/arc.c (arc_sched_issue_rate): Use ARC_TUNE_... .
        (arc_init): Likewise.
        (arc_override_options): Likewise.
        (arc_file_start): Choose Tag_ARC_CPU_variation based on arc_tune
        value.
        (hwloop_fail): Use TARGET_DBNZ when we want to check for dbnz insn
        support.
        * config/arc/arc.h (TARGET_DBNZ): Define.
        * config/arc/arc.md (attr tune): Add core_3, use ARC_TUNE_... to
        properly set the tune attribute.
        (dbnz): Use TARGET_DBNZ guard.
        * config/arc/arc.opt (mtune): Add core3 option.

From-SVN: r257085

5 files changed, 42 insertions, 30 deletions

diff --git a/gcc/config/arc/arc-arch.h b/gcc/config/arc/arc-arch.h
index 29229e0..64866dd 100644
--- a/gcc/config/arc/arc-arch.h
+++ b/gcc/config/arc/arc-arch.h
@@ -72,7 +72,8 @@ enum arc_tune_attr
     ARC_TUNE_NONE,
     ARC_TUNE_ARC600,
     ARC_TUNE_ARC700_4_2_STD,
-    ARC_TUNE_ARC700_4_2_XMAC
+    ARC_TUNE_ARC700_4_2_XMAC,
+    ARC_TUNE_CORE_3
   };
 
 /* CPU specific properties.  */
diff --git a/gcc/config/arc/arc.c b/gcc/config/arc/arc.c
index fc18f65..0c98083 100644
--- a/gcc/config/arc/arc.c
+++ b/gcc/config/arc/arc.c
@@ -848,21 +848,21 @@ arc_init (void)
   if (arc_multcost < 0)
     switch (arc_tune)
       {
-      case TUNE_ARC700_4_2_STD:
+      case ARC_TUNE_ARC700_4_2_STD:
 	/* latency 7;
 	   max throughput (1 multiply + 4 other insns) / 5 cycles.  */
 	arc_multcost = COSTS_N_INSNS (4);
 	if (TARGET_NOMPY_SET)
 	  arc_multcost = COSTS_N_INSNS (30);
 	break;
-      case TUNE_ARC700_4_2_XMAC:
+      case ARC_TUNE_ARC700_4_2_XMAC:
 	/* latency 5;
 	   max throughput (1 multiply + 2 other insns) / 3 cycles.  */
 	arc_multcost = COSTS_N_INSNS (3);
 	if (TARGET_NOMPY_SET)
 	  arc_multcost = COSTS_N_INSNS (30);
 	break;
-      case TUNE_ARC600:
+      case ARC_TUNE_ARC600:
 	if (TARGET_MUL64_SET)
 	  {
 	    arc_multcost = COSTS_N_INSNS (4);
@@ -1202,8 +1202,8 @@ arc_override_options (void)
 #undef ARC_OPT
 
   /* Set Tune option.  */
-  if (arc_tune == TUNE_NONE)
-    arc_tune = (enum attr_tune) arc_selected_cpu->tune;
+  if (arc_tune == ARC_TUNE_NONE)
+    arc_tune = (enum arc_tune_attr) arc_selected_cpu->tune;
 
   if (arc_size_opt_level == 3)
     optimize_size = 1;
@@ -5210,6 +5210,9 @@ static void arc_file_start (void)
 	       TARGET_NO_SDATA_SET ? 0 : 2);
   asm_fprintf (asm_out_file, "\t.arc_attribute Tag_ARC_ABI_exceptions, %d\n",
 	       TARGET_OPTFPE ? 1 : 0);
+  if (TARGET_V2)
+    asm_fprintf (asm_out_file, "\t.arc_attribute Tag_ARC_CPU_variation, %d\n",
+		 arc_tune == ARC_TUNE_CORE_3 ? 3 : 2);
 }
 
 /* Implement `TARGET_ASM_FILE_END'.  */
@@ -7388,11 +7391,11 @@ hwloop_fail (hwloop_info loop)
   rtx test;
   rtx insn = loop->loop_end;
 
-  if (TARGET_V2
+  if (TARGET_DBNZ
       && (loop->length && (loop->length <= ARC_MAX_LOOP_LENGTH))
       && REG_P (loop->iter_reg))
     {
-      /* TARGET_V2 has dbnz instructions.  */
+      /* TARGET_V2 core3 has dbnz instructions.  */
       test = gen_dbnz (loop->iter_reg, loop->start_label);
       insn = emit_jump_insn_before (test, loop->loop_end);
     }
diff --git a/gcc/config/arc/arc.h b/gcc/config/arc/arc.h
index 3802112..1f3ed44 100644
--- a/gcc/config/arc/arc.h
+++ b/gcc/config/arc/arc.h
@@ -1630,5 +1630,7 @@ enum
 /* Custom FP instructions used by QuarkSE EM cpu.  */
 #define TARGET_FPX_QUARK    (TARGET_EM && TARGET_SPFP		\
 			     && (arc_fpu_build == FPX_QK))
+/* DBNZ support is available for ARCv2 core3 cpus.  */
+#define TARGET_DBNZ (TARGET_V2 && (arc_tune == ARC_TUNE_CORE_3))
 
 #endif /* GCC_ARC_H */
diff --git a/gcc/config/arc/arc.md b/gcc/config/arc/arc.md
index 172fd11..2ffd300 100644
--- a/gcc/config/arc/arc.md
+++ b/gcc/config/arc/arc.md
@@ -595,14 +595,16 @@
 ;;   somehow modify them to become inelegible for delay slots if a decision
 ;;   is made that makes conditional execution required.
 
-(define_attr "tune" "none,arc600,arc700_4_2_std,arc700_4_2_xmac"
+(define_attr "tune" "none,arc600,arc700_4_2_std,arc700_4_2_xmac, core_3"
   (const
    (cond [(symbol_ref "arc_tune == TUNE_ARC600")
 	  (const_string "arc600")
 	  (symbol_ref "arc_tune == TUNE_ARC700_4_2_STD")
 	  (const_string "arc700_4_2_std")
 	  (symbol_ref "arc_tune == TUNE_ARC700_4_2_XMAC")
-	  (const_string "arc700_4_2_xmac")]
+	  (const_string "arc700_4_2_xmac")
+	  (symbol_ref "arc_tune == ARC_TUNE_CORE_3")
+	  (const_string "core_3")]
 	 (const_string "none"))))
 
 (define_attr "tune_arc700" "false,true"
@@ -5182,11 +5184,11 @@
 	(plus:SI (match_dup 0)
 		 (const_int -1)))
    (clobber (match_scratch:SI 2 "=X,r"))]
-  "TARGET_V2"
+  "TARGET_DBNZ"
   "@
    dbnz%#\\t%0,%l1
    #"
-  "TARGET_V2 && reload_completed && memory_operand (operands[0], SImode)"
+  "TARGET_DBNZ && reload_completed && memory_operand (operands[0], SImode)"
   [(set (match_dup 2) (match_dup 0))
    (set (match_dup 2) (plus:SI (match_dup 2) (const_int -1)))
    (set (reg:CC CC_REG) (compare:CC (match_dup 2) (const_int 0)))
diff --git a/gcc/config/arc/arc.opt b/gcc/config/arc/arc.opt
index bc11ca1..0c3cdf2 100644
--- a/gcc/config/arc/arc.opt
+++ b/gcc/config/arc/arc.opt
@@ -249,29 +249,33 @@ mmultcost=
 Target RejectNegative Joined UInteger Var(arc_multcost) Init(-1)
 Cost to assume for a multiply instruction, with 4 being equal to a normal insn.
 
-mtune=ARC600
-Target RejectNegative Var(arc_tune, TUNE_ARC600)
-Tune for ARC600 cpu.
+mtune=
+Target RejectNegative ToLower Joined Var(arc_tune) Enum(arc_tune_attr) Init(ARC_TUNE_NONE)
+-mcpu=TUNE Tune code for given ARC variant.
 
-mtune=ARC601
-Target RejectNegative Var(arc_tune, TUNE_ARC600)
-Tune for ARC601 cpu.
+Enum
+Name(arc_tune_attr) Type(int)
+
+EnumValue
+Enum(arc_tune_attr) String(arc600) Value(ARC_TUNE_ARC600)
 
-mtune=ARC700
-Target RejectNegative Var(arc_tune, TUNE_ARC700_4_2_STD)
-Tune for ARC700 R4.2 Cpu with standard multiplier block.
+EnumValue
+Enum(arc_tune_attr) String(arc601) Value(ARC_TUNE_ARC600)
 
-mtune=ARC700-xmac
-Target RejectNegative Var(arc_tune, TUNE_ARC700_4_2_XMAC)
-Tune for ARC700 R4.2 Cpu with XMAC block.
+EnumValue
+Enum(arc_tune_attr) String(arc700) Value(ARC_TUNE_ARC700_4_2_STD)
 
-mtune=ARC725D
-Target RejectNegative Var(arc_tune, TUNE_ARC700_4_2_XMAC)
-Tune for ARC700 R4.2 Cpu with XMAC block.
+EnumValue
+Enum(arc_tune_attr) String(arc700-xmac) Value(ARC_TUNE_ARC700_4_2_XMAC)
 
-mtune=ARC750D
-Target RejectNegative Var(arc_tune, TUNE_ARC700_4_2_XMAC)
-Tune for ARC700 R4.2 Cpu with XMAC block.
+EnumValue
+Enum(arc_tune_attr) String(arc725d) Value(ARC_TUNE_ARC700_4_2_XMAC)
+
+EnumValue
+Enum(arc_tune_attr) String(arc750d) Value(ARC_TUNE_ARC700_4_2_XMAC)
+
+EnumValue
+Enum(arc_tune_attr) String(core3) Value(ARC_TUNE_CORE_3)
 
 mindexed-loads
 Target Var(TARGET_INDEXED_LOADS) Init(TARGET_INDEXED_LOADS_DEFAULT)