Module: ppl/ppl Branch: floating_point Commit: 1bd882f4961087d6686bda5676bd1ba5908dd681 URL: http://www.cs.unipr.it/git/gitweb.cgi?p=ppl/ppl.git;a=commit;h=1bd882f496108...
Author: Fabio Bossi bossi@cs.unipr.it Date: Fri Sep 11 10:50:42 2009 +0200
Added a skeleton for the rest of the affine_image implementation.
---
src/Octagonal_Shape.templates.hh | 36 +++++++++++++++++++++++++++++++++++- 1 files changed, 35 insertions(+), 1 deletions(-)
diff --git a/src/Octagonal_Shape.templates.hh b/src/Octagonal_Shape.templates.hh index b891006..69f876d 100644 --- a/src/Octagonal_Shape.templates.hh +++ b/src/Octagonal_Shape.templates.hh @@ -4752,12 +4752,46 @@ Octagonal_Shape<T>::affine_image(Variable var, return; }
+ // true if b = [0;0]. bool is_b_zero = (b_lb == 0 && b_ub == 0);
if (t == 1) { - + // The one and only non-zero homogeneous coefficient in `lf'. + const FP_Interval_Type& w_coeff = lf.coefficient(Variable(w_id)); + PPL_DIRTY_TEMP(N, w_coeff_lb); + PPL_DIRTY_TEMP(N, w_coeff_ub); + assign_r(w_coeff_lb, w_coeff.lower(), ROUND_NOT_NEEDED); + assign_r(w_coeff_ub, w_coeff.upper(), ROUND_NOT_NEEDED); + // true if w_coeff = [1;1]. + bool is_w_coeff_one = (w_coeff_lb == 1 && w_coeff_ub == 1); + // true if w_coeff = [-1;-1]. + bool is_w_coeff_minus_one = (w_coeff_lb == -1 && w_coeff_ub == -1); + if (is_w_coeff_one || is_w_coeff_minus_one) { + // Case 2: lf = w_coeff*w + b, with w_coeff = [+/-1;+/-1]. + if (w_id == var_id) { + // Here `lf' is of the form: [+/-1;+/-1]* v + b. + if (is_w_coeff_one) { + if (is_b_zero) + // The transformation is the identity function. + return; + else { + + } + } + // Here `w_coeff = [-1;-1]. + } + else { + // Here `w != var', so that `lf' is of the form + // [+/-1;+/-1] * w + b. + } + } }
+ // General case. + // Either t == 2, so that + // expr == i_1*x_1 + i_2*x_2 + ... + i_n*x_n + b, where n >= 2, + // or t == 1, expr == i*w + b, but i <> [+/-1;+/-1]. + // FIXME: complete the implementation.
}