From: Dmitry Melnik <dm@ispras.ru>
To: gcc-patches@gcc.gnu.org
Cc: Richard Earnshaw <rearnsha@arm.com>,
Ramana Radhakrishnan <ramana.radhakrishnan@arm.com>,
Andrey Belevantsev <abel@ispras.ru>
Subject: [PATCH, ARM] Reload register class fix for NEON constants
Date: Mon, 25 Apr 2011 16:45:00 -0000 [thread overview]
Message-ID: <4DB595B3.3080708@ispras.ru> (raw)
[-- Attachment #1: Type: text/plain, Size: 1054 bytes --]
Hi All,
The attached patch changes the reload class for NEON constant vectors
from GENERAL_REGS to NO_REGS.
The issue was found on this code from libevas:
void
_op_blend_p_caa_dp(unsigned *s, unsigned* e, unsigned *d, unsigned c) {
while (d < e) {
*d = ( (((((*s) >> 8) & 0x00ff00ff) * (c)) & 0xff00ff00) +
(((((*s) & 0x00ff00ff) * (c)) >> 8) & 0x00ff00ff) );
//*d = (*s) & 0x00ff00ff;
d++;
s++;
}
}
Original asm:
.L4:
adr r8, .L10
ldmia r8, {r8-fp}
...
vmov d22, r8, r9 @ v4si
vmov d23, sl, fp
vand q12, q8, q11
...
bhi .L4
.L10:
.word 16711935 @ 0xff00ff
.word 16711935
.word 16711935
.word 16711935
Fixed asm:
.L4:
vmov.i16 q11, #255 @ v4si
...
vand q12, q8, q11
bhi .L4
This fix results in +3.7% gain for expedite (reduced) test suite, and up
to 15% for affected tests.
Ok for trunk?
--
Best regards,
Dmitry
[-- Attachment #2: neon-reload-class-fix.diff --]
[-- Type: text/x-diff, Size: 711 bytes --]
2011-04-22 Sergey Grechanik <mouseentity@ispras.ru>
* config/arm/arm.c (coproc_secondary_reload_class): Treat constant
vectors the same way as memory locations to prevent loading them
through the ARM general registers.
--- a/gcc/config/arm/arm.c
+++ b/gcc/config/arm/arm.c
@@ -9152,7 +9152,7 @@ coproc_secondary_reload_class (enum machine_mode mode, rtx x, bool wb)
/* The neon move patterns handle all legitimate vector and struct
addresses. */
if (TARGET_NEON
- && MEM_P (x)
+ && (MEM_P (x) || GET_CODE (x) == CONST_VECTOR)
&& (GET_MODE_CLASS (mode) == MODE_VECTOR_INT
|| GET_MODE_CLASS (mode) == MODE_VECTOR_FLOAT
|| VALID_NEON_STRUCT_MODE (mode)))
next reply other threads:[~2011-04-25 15:39 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-04-25 16:45 Dmitry Melnik [this message]
2011-05-04 10:00 ` Richard Earnshaw
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