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author | Daniel Dunbar <daniel@zuster.org> | 2009-06-26 16:47:03 +0000 |
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committer | Daniel Dunbar <daniel@zuster.org> | 2009-06-26 16:47:03 +0000 |
commit | b3a6901e66f55b35aa9e01bcb24134e6a65ea004 (patch) | |
tree | 4d57d73575ea3f7e30bf430920d6e96fa2a369c1 /lib/ashrdi3.c | |
parent | 8cbe163cba77c772621f89ddb33793ac170b1fa2 (diff) | |
download | compiler-rt-b3a6901e66f55b35aa9e01bcb24134e6a65ea004.tar.gz compiler-rt-b3a6901e66f55b35aa9e01bcb24134e6a65ea004.tar.bz2 compiler-rt-b3a6901e66f55b35aa9e01bcb24134e6a65ea004.tar.xz |
Initial import of compiler-rt.
-
git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@74292 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/ashrdi3.c')
-rw-r--r-- | lib/ashrdi3.c | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/lib/ashrdi3.c b/lib/ashrdi3.c new file mode 100644 index 00000000..fc2e6d84 --- /dev/null +++ b/lib/ashrdi3.c @@ -0,0 +1,41 @@ +//===-- ashrdi3.c - Implement __ashrdi3 -----------------------------------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This file implements __ashrdi3 for the compiler_rt library. +// +//===----------------------------------------------------------------------===// + +#include "int_lib.h" + +// Returns: arithmetic a >> b + +// Precondition: 0 <= b < bits_in_dword + +di_int +__ashrdi3(di_int a, si_int b) +{ + const int bits_in_word = (int)(sizeof(si_int) * CHAR_BIT); + dwords input; + dwords result; + input.all = a; + if (b & bits_in_word) // bits_in_word <= b < bits_in_dword + { + // result.high = input.high < 0 ? -1 : 0 + result.high = input.high >> (bits_in_word - 1); + result.low = input.high >> (b - bits_in_word); + } + else // 0 <= b < bits_in_word + { + if (b == 0) + return a; + result.high = input.high >> b; + result.low = (input.high << (bits_in_word - b)) | (input.low >> b); + } + return result.all; +} |