diff options
Diffstat (limited to 'gcc/tree-affine.c')
| -rw-r--r-- | gcc/tree-affine.c | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/gcc/tree-affine.c b/gcc/tree-affine.c index d2983ab5..f7a5f12 100644 --- a/gcc/tree-affine.c +++ b/gcc/tree-affine.c @@ -24,6 +24,7 @@ along with GCC; see the file COPYING3. If not see #include "rtl.h" #include "tree.h" #include "gimple.h" +#include "ssa.h" #include "tree-pretty-print.h" #include "fold-const.h" #include "tree-affine.h" @@ -393,6 +394,30 @@ tree_to_aff_combination (tree expr, tree type, aff_tree *comb) tree_to_aff_combination (expr, type, comb); return; } + wide_int minv, maxv; + /* If inner type has wrapping overflow behavior, fold conversion + for below case: + (T1)(X - CST) -> (T1)X - (T1)CST + if X - CST doesn't overflow by range information. Also handle + (T1)(X + CST) as (T1)(X - (-CST)). */ + if (TYPE_UNSIGNED (itype) + && TYPE_OVERFLOW_WRAPS (itype) + && TREE_CODE (op0) == SSA_NAME + && TREE_CODE (op1) == INTEGER_CST + && icode != MULT_EXPR + && get_range_info (op0, &minv, &maxv) == VR_RANGE) + { + if (icode == PLUS_EXPR) + op1 = wide_int_to_tree (itype, wi::neg (op1)); + if (wi::geu_p (minv, op1)) + { + op0 = fold_convert (otype, op0); + op1 = fold_convert (otype, op1); + expr = fold_build2 (MINUS_EXPR, otype, op0, op1); + tree_to_aff_combination (expr, type, comb); + return; + } + } } } break; |