[AArch64 costs 13/18] Improve costs for div/mod

[James Greenhalgh]

Hi,

Now DIV/MOD.

Tested in series on aarch64-none-elf.

OK for stage 1?

Thanks,
James

---
2014-03-27  James Greenhalgh  <james.greenha...@arm.com>
            Philipp Tomsich  <philipp.toms...@theobroma-systems.com>

        * config/aarch64/aarch64.c (aarch64_rtx_costs): Improve costs for
        DIV/MOD.

diff --git a/gcc/config/aarch64/aarch64.c b/gcc/config/aarch64/aarch64.c
index 338f6b3..c6f1ac5 100644
--- a/gcc/config/aarch64/aarch64.c
+++ b/gcc/config/aarch64/aarch64.c
@@ -5423,7 +5423,6 @@ cost_minus:
 
     case MOD:
     case UMOD:
-      *cost = COSTS_N_INSNS (2);
       if (speed)
 	{
 	  if (GET_MODE_CLASS (GET_MODE (x)) == MODE_INT)
@@ -5440,15 +5439,15 @@ cost_minus:
 
     case DIV:
     case UDIV:
-      *cost = COSTS_N_INSNS (1);
+    case SQRT:
       if (speed)
 	{
-	  if (GET_MODE_CLASS (GET_MODE (x)) == MODE_INT)
-	    *cost += extra_cost->mult[GET_MODE (x) == DImode].idiv;
-	  else if (GET_MODE (x) == DFmode)
-	    *cost += extra_cost->fp[1].div;
-	  else if (GET_MODE (x) == SFmode)
-	    *cost += extra_cost->fp[0].div;
+	  if (GET_MODE_CLASS (mode) == MODE_INT)
+	    /* There is no integer SQRT, so only DIV and UDIV can get
+	       here.  */
+	    *cost += extra_cost->mult[mode == DImode].idiv;
+	  else
+	    *cost += extra_cost->fp[mode == DFmode].div;
 	}
       return false;  /* All arguments need to be in registers.  */