diff options
author | Keith Isdale <keith.isdale@nokia.com> | 2010-07-26 14:56:53 +1000 |
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committer | Keith Isdale <keith.isdale@nokia.com> | 2010-07-26 14:56:53 +1000 |
commit | 9f034793bcfc51c2b7c1dd14db806f7258f9a9eb (patch) | |
tree | 63bd0f50ce5b77828ad8205eafd7b9412810499e /botan/src/math/bigint/mulop_generic/mp_mulop.cpp | |
parent | 619d92cfef29e653bfdf852e83888e50cfc4348f (diff) | |
parent | 65271649dbc90f3af1184ad1b23bdb64c0c07d07 (diff) |
Merge branch 'master' of git://git-nokia.trolltech.com.au/qtsoftware/research/qtuitest
Diffstat (limited to 'botan/src/math/bigint/mulop_generic/mp_mulop.cpp')
-rw-r--r-- | botan/src/math/bigint/mulop_generic/mp_mulop.cpp | 77 |
1 files changed, 77 insertions, 0 deletions
diff --git a/botan/src/math/bigint/mulop_generic/mp_mulop.cpp b/botan/src/math/bigint/mulop_generic/mp_mulop.cpp new file mode 100644 index 0000000..4647d00 --- /dev/null +++ b/botan/src/math/bigint/mulop_generic/mp_mulop.cpp @@ -0,0 +1,77 @@ +/* +* Simple O(N^2) Multiplication and Squaring +* (C) 1999-2008 Jack Lloyd +* +* Distributed under the terms of the Botan license +*/ + +#include <botan/mp_asm.h> +#include <botan/mp_asmi.h> +#include <botan/mp_core.h> +#include <botan/mem_ops.h> + +namespace Botan { + +extern "C" { + +/* +* Simple O(N^2) Multiplication +*/ +void bigint_simple_mul(word z[], const word x[], u32bit x_size, + const word y[], u32bit y_size) + { + const u32bit x_size_8 = x_size - (x_size % 8); + + clear_mem(z, x_size + y_size); + + for(u32bit i = 0; i != y_size; ++i) + { + const word y_i = y[i]; + + word carry = 0; + + for(u32bit j = 0; j != x_size_8; j += 8) + carry = word8_madd3(z + i + j, x + j, y_i, carry); + + for(u32bit j = x_size_8; j != x_size; ++j) + z[i+j] = word_madd3(x[j], y_i, z[i+j], &carry); + + z[x_size+i] = carry; + } + } + +/* +* Simple O(N^2) Squaring + +This is exactly the same algorithm as bigint_simple_mul, +however because C/C++ compilers suck at alias analysis it +is good to have the version where the compiler knows +that x == y + +There is an O(n^1.5) squaring algorithm specified in Handbook of +Applied Cryptography, chapter 14 +*/ +void bigint_simple_sqr(word z[], const word x[], u32bit x_size) + { + const u32bit x_size_8 = x_size - (x_size % 8); + + clear_mem(z, 2*x_size); + + for(u32bit i = 0; i != x_size; ++i) + { + const word x_i = x[i]; + word carry = 0; + + for(u32bit j = 0; j != x_size_8; j += 8) + carry = word8_madd3(z + i + j, x + j, x_i, carry); + + for(u32bit j = x_size_8; j != x_size; ++j) + z[i+j] = word_madd3(x[j], x_i, z[i+j], &carry); + + z[x_size+i] = carry; + } + } + +} + +} |