[PATCH] AArch64: Improve regmove_costs for 128-bit types

[Wilco Dijkstra]

Hi,

This patch improves the register move costs for 128-bit types.

OK for commit?

ChangeLog:
2014-09-15  Wilco Dijkstra <wdijkstr@arm.com>

	* gcc/config/aarch64/aarch64.c (aarch64_register_move_cost):
	Add register move costs for 128-bit types.

---
 gcc/config/aarch64/aarch64.c | 29 +++++++++++++++++++++--------
 1 file changed, 21 insertions(+), 8 deletions(-)

diff --git a/gcc/config/aarch64/aarch64.c b/gcc/config/aarch64/aarch64.c
index 51e2c70..b032e93 100644
--- a/gcc/config/aarch64/aarch64.c
+++ b/gcc/config/aarch64/aarch64.c
@@ -5950,6 +5950,27 @@ aarch64_register_move_cost (enum machine_mode mode,
     return aarch64_register_move_cost (mode, from, GENERAL_REGS)
             + aarch64_register_move_cost (mode, GENERAL_REGS, to);
 
+  if (GET_MODE_SIZE (mode) == 16)
+    {
+      /* 128-bit operations on general registers require 2 instructions.  */
+      if (from == GENERAL_REGS && to == GENERAL_REGS)
+	return regmove_cost->GP2GP * 2;
+      else if (from == GENERAL_REGS)
+	return regmove_cost->GP2FP * 2;
+      else if (to == GENERAL_REGS)
+	return regmove_cost->FP2GP * 2;
+
+      /* When AdvSIMD instructions are disabled it is not possible to move
+	 a 128-bit value directly between Q registers.  This is handled in
+	 secondary reload.  A general register is used as a scratch to move
+	 the upper DI value and the lower DI value is moved directly,
+	 hence the cost is the sum of three moves. */
+      if (! TARGET_SIMD)
+	return regmove_cost->GP2FP + regmove_cost->FP2GP + regmove_cost->FP2FP;
+
+      return regmove_cost->FP2FP;
+    }
+
   if (from == GENERAL_REGS && to == GENERAL_REGS)
     return regmove_cost->GP2GP;
   else if (from == GENERAL_REGS)
@@ -5957,14 +5978,6 @@ aarch64_register_move_cost (enum machine_mode mode,
   else if (to == GENERAL_REGS)
     return regmove_cost->FP2GP;
 
-  /* When AdvSIMD instructions are disabled it is not possible to move
-     a 128-bit value directly between Q registers.  This is handled in
-     secondary reload.  A general register is used as a scratch to move
-     the upper DI value and the lower DI value is moved directly,
-     hence the cost is the sum of three moves. */
-  if (! TARGET_SIMD && GET_MODE_SIZE (mode) == 16)
-    return regmove_cost->GP2FP + regmove_cost->FP2GP + regmove_cost->FP2FP;
-
   return regmove_cost->FP2FP;
 }
 
-- 
1.9.1