re PR target/45336 (pextr{b,w,d}, (worse than) redundant extensions)

PR target/45336
	* simplify-rtx.c (simplify_unary_operation_1): Optimize nested
	SIGN_EXTENDs or ZERO_EXTENDs.

From-SVN: r163384
This commit is contained in:
Jakub Jelinek 2010-08-19 19:43:50 +02:00 committed by Jakub Jelinek
parent 0524d2d662
commit a5d8253f7a
2 changed files with 36 additions and 0 deletions

View File

@ -1,3 +1,9 @@
2010-08-19 Jakub Jelinek <jakub@redhat.com>
PR target/45336
* simplify-rtx.c (simplify_unary_operation_1): Optimize nested
SIGN_EXTENDs or ZERO_EXTENDs.
2010-08-19 Bernd Schmidt <bernds@codesourcery.com>
PR target/42172

View File

@ -1010,6 +1010,31 @@ simplify_unary_operation_1 (enum rtx_code code, enum machine_mode mode, rtx op)
&& GET_MODE_SIZE (mode) <= GET_MODE_SIZE (GET_MODE (XEXP (op, 0))))
return rtl_hooks.gen_lowpart_no_emit (mode, op);
/* (sign_extend:M (sign_extend:N <X>)) is (sign_extend:M <X>). */
if (GET_CODE (op) == SIGN_EXTEND)
return simplify_gen_unary (SIGN_EXTEND, mode, XEXP (op, 0),
GET_MODE (XEXP (op, 0)));
/* (sign_extend:M (ashiftrt:N (ashift <X> (const_int I)) (const_int I)))
is (sign_extend:M (subreg:O <X>)) if there is mode with
GET_MODE_BITSIZE (N) - I bits. */
if (GET_CODE (op) == ASHIFTRT
&& GET_CODE (XEXP (op, 0)) == ASHIFT
&& CONST_INT_P (XEXP (op, 1))
&& XEXP (XEXP (op, 0), 1) == XEXP (op, 1)
&& GET_MODE_BITSIZE (GET_MODE (op)) > INTVAL (XEXP (op, 1)))
{
enum machine_mode tmode
= mode_for_size (GET_MODE_BITSIZE (GET_MODE (op))
- INTVAL (XEXP (op, 1)), MODE_INT, 1);
if (tmode != BLKmode)
{
rtx inner =
rtl_hooks.gen_lowpart_no_emit (tmode, XEXP (XEXP (op, 0), 0));
return simplify_gen_unary (SIGN_EXTEND, mode, inner, tmode);
}
}
#if defined(POINTERS_EXTEND_UNSIGNED) && !defined(HAVE_ptr_extend)
/* As we do not know which address space the pointer is refering to,
we can do this only if the target does not support different pointer
@ -1036,6 +1061,11 @@ simplify_unary_operation_1 (enum rtx_code code, enum machine_mode mode, rtx op)
&& GET_MODE_SIZE (mode) <= GET_MODE_SIZE (GET_MODE (XEXP (op, 0))))
return rtl_hooks.gen_lowpart_no_emit (mode, op);
/* (zero_extend:M (zero_extend:N <X>)) is (zero_extend:M <X>). */
if (GET_CODE (op) == ZERO_EXTEND)
return simplify_gen_unary (ZERO_EXTEND, mode, XEXP (op, 0),
GET_MODE (XEXP (op, 0)));
#if defined(POINTERS_EXTEND_UNSIGNED) && !defined(HAVE_ptr_extend)
/* As we do not know which address space the pointer is refering to,
we can do this only if the target does not support different pointer