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aarch64.c (aarch64_legitimize_address): New function.

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* config/aarch64/aarch64.c (aarch64_legitimize_address): New function.
	(TARGET_LEGITIMIZE_ADDRESS): Redefine.

From-SVN: r216336
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Richard Earnshaw 2014-10-16 16:19:48 +00:00 committed by Richard Earnshaw
parent 29fe1a72cb
commit 0c4ec427e0
2 changed files with 49 additions and 0 deletions
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gcc/ChangeLog
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@ -1,3 +1,8 @@
2014-10-16 Richard Earnshaw <rearnsha@arm.com>
* config/aarch64/aarch64.c (aarch64_legitimize_address): New function.
(TARGET_LEGITIMIZE_ADDRESS): Redefine.
2014-10-16 Oleg Endo <olegendo@gcc.gnu.org>
* config/sh/sh-protos.h (fldi_ok): Remove.

44
gcc/config/aarch64/aarch64.c
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@ -4167,6 +4167,47 @@ aarch64_regno_regclass (unsigned regno)
return NO_REGS;
}
static rtx
aarch64_legitimize_address (rtx x, rtx /* orig_x */, enum machine_mode mode)
{
/* Try to split X+CONST into Y=X+(CONST & ~mask), Y+(CONST&mask),
where mask is selected by alignment and size of the offset.
We try to pick as large a range for the offset as possible to
maximize the chance of a CSE. However, for aligned addresses
we limit the range to 4k so that structures with different sized
elements are likely to use the same base. */
if (GET_CODE (x) == PLUS && CONST_INT_P (XEXP (x, 1)))
{
HOST_WIDE_INT offset = INTVAL (XEXP (x, 1));
HOST_WIDE_INT base_offset;
/* Does it look like we'll need a load/store-pair operation? */
if (GET_MODE_SIZE (mode) > 16
|| mode == TImode)
base_offset = ((offset + 64 * GET_MODE_SIZE (mode))
& ~((128 * GET_MODE_SIZE (mode)) - 1));
/* For offsets aren't a multiple of the access size, the limit is
-256...255. */
else if (offset & (GET_MODE_SIZE (mode) - 1))
base_offset = (offset + 0x100) & ~0x1ff;
else
base_offset = offset & ~0xfff;
if (base_offset == 0)
return x;
offset -= base_offset;
rtx base_reg = gen_reg_rtx (Pmode);
rtx val = force_operand (plus_constant (Pmode, XEXP (x, 0), base_offset),
NULL_RTX);
emit_move_insn (base_reg, val);
x = plus_constant (Pmode, base_reg, offset);
}
return x;
}
/* Try a machine-dependent way of reloading an illegitimate address
operand. If we find one, push the reload and return the new rtx. */
@ -10165,6 +10206,9 @@ aarch64_asan_shadow_offset (void)
#undef TARGET_ASAN_SHADOW_OFFSET
#define TARGET_ASAN_SHADOW_OFFSET aarch64_asan_shadow_offset
#undef TARGET_LEGITIMIZE_ADDRESS
#define TARGET_LEGITIMIZE_ADDRESS aarch64_legitimize_address
struct gcc_target targetm = TARGET_INITIALIZER;
#include "gt-aarch64.h"