sh: Add plain udivsi3 (not _i4*) for gcc-4.1 and lower.

We chan't share code for udivsi3 and udivsi3_i4, because they
have a different clobber list. Copy udivsi3 from gcc-4.1.2.

As shown in arch/sh/lib/udivsi3.S (and -Os.S),

  .global __udivsi3_i4i
  .global __udivsi3_i4
  .global __udivsi3
__udivsi3_i4i:
  ...

Three symbols are sharing one code, which is actually udivsi3_i4i.
But, this results unwanted code with gcc 4.1.

In gcc, these three are treated as pseudo instructions that have
their own clobber list apart from the usual calling convention.

According to sh's machine description. The clobber list is as
follows:

 - udivsi3_i4i : t,r1,pr,mach,macl
 - udivsi3_i4  : t,r0,r1,r4,r5,pr,dr0,dr2,dr4
 - udivsi3     : t,r4,pr

The caller of udivsi3 will be left with a broken r1 and mac*.

gcc-4.1.x and older(at least to 3.4) generate udivsi3.
ST's gcc-4.1.1 seems to be OK because it has _i4i.

Signed-off-by: Takashi YOSHII <yoshii.takashi@renesas.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

1 files changed, 149 insertions, 0 deletions

diff --git a/arch/sh/lib/udivsi3_i4i-Os.S b/arch/sh/lib/udivsi3_i4i-Os.S
new file mode 100644
index 00000000000..4835553e1ea
--- /dev/null
+++ b/arch/sh/lib/udivsi3_i4i-Os.S
@@ -0,0 +1,149 @@
+/* Copyright (C) 2006 Free Software Foundation, Inc.
+
+This file is free software; you can redistribute it and/or modify it
+under the terms of the GNU General Public License as published by the
+Free Software Foundation; either version 2, or (at your option) any
+later version.
+
+In addition to the permissions in the GNU General Public License, the
+Free Software Foundation gives you unlimited permission to link the
+compiled version of this file into combinations with other programs,
+and to distribute those combinations without any restriction coming
+from the use of this file.  (The General Public License restrictions
+do apply in other respects; for example, they cover modification of
+the file, and distribution when not linked into a combine
+executable.)
+
+This file is distributed in the hope that it will be useful, but
+WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; see the file COPYING.  If not, write to
+the Free Software Foundation, 51 Franklin Street, Fifth Floor,
+Boston, MA 02110-1301, USA.  */
+
+/* Moderately Space-optimized libgcc routines for the Renesas SH /
+   STMicroelectronics ST40 CPUs.
+   Contributed by J"orn Rennecke joern.rennecke@st.com.  */
+
+/* Size: 186 bytes jointly for udivsi3_i4i and sdivsi3_i4i
+   sh4-200 run times:
+   udiv small divisor: 55 cycles
+   udiv large divisor: 52 cycles
+   sdiv small divisor, positive result: 59 cycles
+   sdiv large divisor, positive result: 56 cycles
+   sdiv small divisor, negative result: 65 cycles (*)
+   sdiv large divisor, negative result: 62 cycles (*)
+   (*): r2 is restored in the rts delay slot and has a lingering latency
+        of two more cycles.  */
+	.balign 4
+	.global	__udivsi3_i4i
+	.global	__udivsi3_i4
+	.set	__udivsi3_i4, __udivsi3_i4i
+	.type	__udivsi3_i4i, @function
+	.type	__sdivsi3_i4i, @function
+__udivsi3_i4i:
+	sts pr,r1
+	mov.l r4,@-r15
+	extu.w r5,r0
+	cmp/eq r5,r0
+	swap.w r4,r0
+	shlr16 r4
+	bf/s large_divisor
+	div0u
+	mov.l r5,@-r15
+	shll16 r5
+sdiv_small_divisor:
+	div1 r5,r4
+	bsr div6
+	div1 r5,r4
+	div1 r5,r4
+	bsr div6
+	div1 r5,r4
+	xtrct r4,r0
+	xtrct r0,r4
+	bsr div7
+	swap.w r4,r4
+	div1 r5,r4
+	bsr div7
+	div1 r5,r4
+	xtrct r4,r0
+	mov.l @r15+,r5
+	swap.w r0,r0
+	mov.l @r15+,r4
+	jmp @r1
+	rotcl r0
+div7:
+	div1 r5,r4
+div6:
+	            div1 r5,r4; div1 r5,r4; div1 r5,r4
+	div1 r5,r4; div1 r5,r4; rts;        div1 r5,r4
+
+divx3:
+	rotcl r0
+	div1 r5,r4
+	rotcl r0
+	div1 r5,r4
+	rotcl r0
+	rts
+	div1 r5,r4
+
+large_divisor:
+	mov.l r5,@-r15
+sdiv_large_divisor:
+	xor r4,r0
+	.rept 4
+	rotcl r0
+	bsr divx3
+	div1 r5,r4
+	.endr
+	mov.l @r15+,r5
+	mov.l @r15+,r4
+	jmp @r1
+	rotcl r0
+
+	.global	__sdivsi3_i4i
+	.global __sdivsi3_i4
+	.global __sdivsi3
+	.set	__sdivsi3_i4, __sdivsi3_i4i
+	.set	__sdivsi3, __sdivsi3_i4i
+__sdivsi3_i4i:
+	mov.l r4,@-r15
+	cmp/pz r5
+	mov.l r5,@-r15
+	bt/s pos_divisor
+	cmp/pz r4
+	neg r5,r5
+	extu.w r5,r0
+	bt/s neg_result
+	cmp/eq r5,r0
+	neg r4,r4
+pos_result:
+	swap.w r4,r0
+	bra sdiv_check_divisor
+	sts pr,r1
+pos_divisor:
+	extu.w r5,r0
+	bt/s pos_result
+	cmp/eq r5,r0
+	neg r4,r4
+neg_result:
+	mova negate_result,r0
+	;
+	mov r0,r1
+	swap.w r4,r0
+	lds r2,macl
+	sts pr,r2
+sdiv_check_divisor:
+	shlr16 r4
+	bf/s sdiv_large_divisor
+	div0u
+	bra sdiv_small_divisor
+	shll16 r5
+	.balign 4
+negate_result:
+	neg r0,r0
+	jmp @r2
+	sts macl,r2