[Patch 6/7 AArch64] Deprecate *_BY_PIECES_P, move to hookized version

[James Greenhalgh <james dot greenhalgh at arm dot com>]

Hi,

This patch moves aarch64 to TARGET_USE_BY_PIECES_INFRASTRUCTURE_P.

AArch64 turns off STORE_BY_PIECES, so honour that and use the default
implementation for other operations.

Unlike the other patches in this series I do actually have some
hardware for AArch64! So this one has been through a bootstrap run
with no issues.

OK?

Cheers,
James

---
gcc/

2014-10-31  James Greenhalgh  <james.greenhalgh@arm.com>

	* config/aarch64/aarch64.c
	(aarch64_use_by_pieces_infrastructre_p): New.
	(TARGET_USE_BY_PIECES_INFRASTRUCTURE): Likewise.
	* config/aarch64/aarch64.h (STORE_BY_PIECES_P): Delete.

diff --git a/gcc/config/aarch64/aarch64.c b/gcc/config/aarch64/aarch64.c
index 0400fd5..9aeac7c 100644
--- a/gcc/config/aarch64/aarch64.c
+++ b/gcc/config/aarch64/aarch64.c
@@ -10001,6 +10001,22 @@ aarch64_asan_shadow_offset (void)
   return (HOST_WIDE_INT_1 << 36);
 }
 
+static bool
+aarch64_use_by_pieces_infrastructure_p (unsigned int size,
+					unsigned int align,
+					enum by_pieces_operation op,
+					bool speed_p)
+{
+  /* STORE_BY_PIECES can be used when copying a constant string, but
+     in that case each 64-bit chunk takes 5 insns instead of 2 (LDR/STR).
+     For now we always fail this and let the move_by_pieces code copy
+     the string from read-only memory.  */
+  if (op == STORE_BY_PIECES)
+    return false;
+
+  return default_use_by_pieces_infrastructure_p (size, align, op, speed_p);
+}
+
 #undef TARGET_ADDRESS_COST
 #define TARGET_ADDRESS_COST aarch64_address_cost
 
@@ -10253,6 +10269,10 @@ aarch64_asan_shadow_offset (void)
 #undef TARGET_LEGITIMIZE_ADDRESS
 #define TARGET_LEGITIMIZE_ADDRESS aarch64_legitimize_address
 
+#undef TARGET_USE_BY_PIECES_INFRASTRUCTURE_P
+#define TARGET_USE_BY_PIECES_INFRASTRUCTURE_P \
+  aarch64_use_by_pieces_infrastructure_p
+
 struct gcc_target targetm = TARGET_INITIALIZER;
 
 #include "gt-aarch64.h"
diff --git a/gcc/config/aarch64/aarch64.h b/gcc/config/aarch64/aarch64.h
index 97b1848..e22163e 100644
--- a/gcc/config/aarch64/aarch64.h
+++ b/gcc/config/aarch64/aarch64.h
@@ -723,12 +723,6 @@ do {									     \
 #define SET_RATIO(speed) \
   ((speed) ? 15 : AARCH64_CALL_RATIO - 2)
 
-/* STORE_BY_PIECES_P can be used when copying a constant string, but
-   in that case each 64-bit chunk takes 5 insns instead of 2 (LDR/STR).
-   For now we always fail this and let the move_by_pieces code copy
-   the string from read-only memory.  */
-#define STORE_BY_PIECES_P(SIZE, ALIGN) 0
-
 /* Disable auto-increment in move_by_pieces et al.  Use of auto-increment is
    rarely a good idea in straight-line code since it adds an extra address
    dependency between each instruction.  Better to use incrementing offsets.  */