Mercurial > hg > CbC > CbC_gcc
annotate gcc/config/picochip/libgccExtras/ashlsi3.c @ 67:f6334be47118
update gcc from gcc-4.6-20100522 to gcc-4.6-20110318
| author | nobuyasu <dimolto@cr.ie.u-ryukyu.ac.jp> |
|---|---|
| date | Tue, 22 Mar 2011 17:18:12 +0900 |
| parents | a06113de4d67 |
| children |
| rev | line source |
|---|---|
| 0 | 1 /* |
| 2 | |
| 3 picoChip GCC support for 32-bit shift left. | |
| 4 | |
| 5 Copyright (C) 2003, 2004, 2005, 2008, 2009 Free Software Foundation, Inc. | |
|
67
f6334be47118
update gcc from gcc-4.6-20100522 to gcc-4.6-20110318
nobuyasu <dimolto@cr.ie.u-ryukyu.ac.jp>
parents:
0
diff
changeset
|
6 Contributed by Picochip Ltd. |
| 0 | 7 Maintained by Daniel Towner (daniel.towner@picochip.com) |
| 8 | |
| 9 This file is free software; you can redistribute it and/or modify it | |
| 10 under the terms of the GNU General Public License as published by the | |
| 11 Free Software Foundation; either version 3, or (at your option) any | |
| 12 later version. | |
| 13 | |
| 14 This file is distributed in the hope that it will be useful, but | |
| 15 WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| 17 General Public License for more details. | |
| 18 | |
| 19 Under Section 7 of GPL version 3, you are granted additional | |
| 20 permissions described in the GCC Runtime Library Exception, version | |
| 21 3.1, as published by the Free Software Foundation. | |
| 22 | |
| 23 You should have received a copy of the GNU General Public License and | |
| 24 a copy of the GCC Runtime Library Exception along with this program; | |
| 25 see the files COPYING3 and COPYING.RUNTIME respectively. If not, see | |
| 26 <http://www.gnu.org/licenses/>. */ | |
| 27 | |
| 28 #ifndef PICOCHIP | |
| 29 #error "Intended for compilation for PICOCHIP only." | |
| 30 #endif | |
| 31 | |
| 32 typedef int HItype __attribute__ ((mode (HI))); | |
| 33 typedef unsigned int UHItype __attribute__ ((mode (HI))); | |
| 34 typedef unsigned int USItype __attribute__ ((mode (SI))); | |
| 35 | |
| 36 typedef struct USIstruct { | |
| 37 UHItype low, high; | |
| 38 } USIstruct; | |
| 39 | |
| 40 typedef union USIunion { | |
| 41 USItype l; | |
| 42 USIstruct s; | |
| 43 } USIunion; | |
| 44 | |
| 45 USItype __ashlsi3(USIunion value, HItype count) { | |
| 46 USIunion result; | |
| 47 int temp; | |
| 48 | |
| 49 /* Ignore a zero count until we get into the (count < 16) | |
| 50 clause. This is slightly slower when shifting by zero, but faster | |
| 51 and smaller in all other cases (due to the better scheduling | |
| 52 opportunities available by putting the test near computational | |
| 53 instructions. */ | |
| 54 /* if (count == 0) return value.l; */ | |
| 55 | |
| 56 if (count < 16) { | |
| 57 /* Shift low and high words by the count. */ | |
| 58 result.s.low = value.s.low << count; | |
| 59 result.s.high = value.s.high << count; | |
| 60 | |
| 61 /* There is now a hole in the lower `count' bits of the high | |
| 62 word. Shift the upper `count' bits of the low word into the | |
| 63 high word. This is only required when the count is non-zero. */ | |
| 64 if (count != 0) { | |
| 65 temp = 16 - count; | |
| 66 temp = value.s.low >> temp; | |
| 67 result.s.high |= temp; | |
| 68 } | |
| 69 | |
| 70 } else { | |
| 71 /* Shift the lower word of the source into the upper word of the | |
| 72 result, and zero the result's lower word. */ | |
| 73 count -= 16; | |
| 74 result.s.high = value.s.low << count; | |
| 75 result.s.low = 0; | |
| 76 | |
| 77 } | |
| 78 | |
| 79 return result.l; | |
| 80 | |
| 81 } | |
| 82 |