diff mbox

[PING,AArch64] Implement ALU_BRANCH fusion

Message ID CO2PR07MB2694AC291A47AE9109CFC1C283110@CO2PR07MB2694.namprd07.prod.outlook.com
State New
Headers show

Commit Message

Hurugalawadi, Naveen April 26, 2017, 12:52 p.m. UTC 
Hi Wilco,

>> Same comment for this part, we want to return true if we match:

Thanks for pointing out about the confusion.

>> Note writing these complex conditions using positive logic makes them much
>> more readable - if you have to negate use !(X && Y && Z) rather than
>> !X || !Y || !Z.

Modified the code as required.

Bootstrapped and Regression tested on AArch64 and X86_64.
Please review the patch and let us know if its okay?

Thanks,
Naveen

Comments

Wilco Dijkstra April 26, 2017, 2:13 p.m. UTC | #1 
Hi Naveen,

This version has the same issue of claiming that all instructions should
be fused except for the cases that can be fused. You should only return
true if there is a match, not if there is not a match.

Cheers,
Wilco
diff mbox

Patch

diff --git a/gcc/config/aarch64/aarch64-fusion-pairs.def b/gcc/config/aarch64/aarch64-fusion-pairs.def
index f0e6dbc..300cd00 100644
--- a/gcc/config/aarch64/aarch64-fusion-pairs.def
+++ b/gcc/config/aarch64/aarch64-fusion-pairs.def
@@ -34,5 +34,6 @@  AARCH64_FUSION_PAIR ("movk+movk", MOVK_MOVK)
 AARCH64_FUSION_PAIR ("adrp+ldr", ADRP_LDR)
 AARCH64_FUSION_PAIR ("cmp+branch", CMP_BRANCH)
 AARCH64_FUSION_PAIR ("aes+aesmc", AES_AESMC)
+AARCH64_FUSION_PAIR ("alu+branch", ALU_BRANCH)
 
 #undef AARCH64_FUSION_PAIR
diff --git a/gcc/config/aarch64/aarch64.c b/gcc/config/aarch64/aarch64.c
index 2e385c4..1a63ad0 100644
--- a/gcc/config/aarch64/aarch64.c
+++ b/gcc/config/aarch64/aarch64.c
@@ -792,7 +792,8 @@  static const struct tune_params thunderx2t99_tunings =
   &generic_approx_modes,
   4, /* memmov_cost.  */
   4, /* issue_rate.  */
-  (AARCH64_FUSE_CMP_BRANCH | AARCH64_FUSE_AES_AESMC), /* fusible_ops  */
+  (AARCH64_FUSE_CMP_BRANCH | AARCH64_FUSE_AES_AESMC
+   | AARCH64_FUSE_ALU_BRANCH), /* fusible_ops  */
   16,	/* function_align.  */
   8,	/* jump_align.  */
   16,	/* loop_align.  */
@@ -13982,6 +13992,49 @@  aarch_macro_fusion_pair_p (rtx_insn *prev, rtx_insn *curr)
         return true;
     }
 
+  if (aarch64_fusion_enabled_p (AARCH64_FUSE_ALU_BRANCH)
+      && any_condjump_p (curr))
+    {
+      /* We're trying to match:
+	  prev (alu_insn) == (set (r0) plus ((r0) (r1/imm)))
+	  curr (cbz) ==  (set (pc) (if_then_else (eq/ne) (r0)
+							 (const_int 0))
+						 (label_ref ("SYM"))
+						 (pc))  */
+      if (! (SET_DEST (curr_set) == (pc_rtx)
+	     && GET_CODE (SET_SRC (curr_set)) == IF_THEN_ELSE
+	     && REG_P (XEXP (XEXP (SET_SRC (curr_set), 0), 0))
+	     && REG_P (SET_DEST (prev_set))
+	     && REGNO (SET_DEST (prev_set))
+		== REGNO (XEXP (XEXP (SET_SRC (curr_set), 0), 0))))
+	return true;
+
+      /* Fuse ALU operations followed by conditional branch instruction.  */
+      switch (get_attr_type (prev))
+	{
+	case TYPE_ALU_IMM:
+	case TYPE_ALU_SREG:
+	case TYPE_ADC_REG:
+	case TYPE_ADC_IMM:
+	case TYPE_ADCS_REG:
+	case TYPE_ADCS_IMM:
+	case TYPE_LOGIC_REG:
+	case TYPE_LOGIC_IMM:
+	case TYPE_CSEL:
+	case TYPE_ADR:
+	case TYPE_MOV_IMM:
+	case TYPE_SHIFT_REG:
+	case TYPE_SHIFT_IMM:
+	case TYPE_BFM:
+	case TYPE_RBIT:
+	case TYPE_REV:
+	case TYPE_EXTEND:
+	  return true;
+
+	default:;
+	}
+    }
+
   return false;
 }