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-rw-r--r--config/picochip/libgccExtras/lshrsi3.c81
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diff --git a/config/picochip/libgccExtras/lshrsi3.c b/config/picochip/libgccExtras/lshrsi3.c
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+/*
+
+picoChip GCC support for 32-bit logical shift right.
+
+Copyright (C) 2003, 2004, 2005 Free Software Foundation, Inc.
+Contributed by picoChip Designs Ltd.
+Maintained by Daniel Towner (daniel.towner@picochip.com)
+
+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. */
+
+typedef int HItype __attribute__ ((mode (HI)));
+typedef unsigned int UHItype __attribute__ ((mode (HI)));
+typedef unsigned int USItype __attribute__ ((mode (SI)));
+
+typedef struct USIstruct {
+ UHItype low, high;
+} USIstruct;
+
+typedef union USIunion {
+ USItype l;
+ USIstruct s;
+} USIunion;
+
+USItype __lshrsi3(USIunion value, HItype count) {
+ USIunion result;
+ int temp;
+
+ /* Ignore a zero count until we get into the (count < 16)
+ clause. This is slightly slower when shifting by zero, but faster
+ and smaller in all other cases (due to the better scheduling
+ opportunities available by putting the test near computational
+ instructions. */
+
+ if (count < 16) {
+ /* Shift low and high words by the count. */
+ result.s.low = value.s.low >> count;
+ result.s.high = value.s.high >> count;
+
+ /* There is now a hole in the upper `count' bits of the low
+ word. Shift the lower `count' bits of the upper word into the
+ low word. This only works when count isn't zero. */
+ if (count != 0) {
+ temp = value.s.high << (16 - count);
+ result.s.low |= temp;
+ }
+
+ } else {
+ /* Shift the upper word of the source into the lower word of the
+ result, and zero the result's upper word. Note that we actually
+ ned to shift by (count - 16), but as we are only using the
+ bottom 4 bits, this is equivalent to shifting by count. */
+ result.s.low = value.s.high >> count;
+ result.s.high = 0;
+
+ }
+
+ return result.l;
+
+}