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| author | Eric Botcazou <ebotcazou@libertysurf.fr> | 2005-04-05 09:06:23 +0200 |
|---|---|---|
| committer | Eric Botcazou <ebotcazou@gcc.gnu.org> | 2005-04-05 07:06:23 +0000 |
| commit | c4cdbeb4802cec34a912e343629d8e28b20128c7 (patch) | |
| tree | 1742287c835dba65c2423d55c9ca50faf649778d | |
| parent | 3c5ead4814e7a0b4f155b84271665cbafd50a120 (diff) | |
| download | gcc-c4cdbeb4802cec34a912e343629d8e28b20128c7.zip gcc-c4cdbeb4802cec34a912e343629d8e28b20128c7.tar.gz gcc-c4cdbeb4802cec34a912e343629d8e28b20128c7.tar.bz2 | |
re PR tree-optimization/19903 (ACATS cxa4006 cxa4017 fail at runtime)
PR tree-optimization/19903
* tree-chrec.c (chrec_convert): Return chrec_dont_know for constants
that don't fit in their type after conversion.
Co-Authored-By: Sebastian Pop <sebastian.pop@cri.ensmp.fr>
From-SVN: r97607
| -rw-r--r-- | gcc/ChangeLog | 7 | ||||
| -rw-r--r-- | gcc/tree-chrec.c | 30 |
2 files changed, 36 insertions, 1 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 9f3a372..bbbade7 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,10 @@ +2005-04-05 Eric Botcazou <ebotcazou@libertysurf.fr> + Sebastian Pop <sebastian.pop@cri.ensmp.fr> + + PR tree-optimization/19903 + * tree-chrec.c (chrec_convert): Return chrec_dont_know for constants + that don't fit in their type after conversion. + 2005-04-05 Uros Bizjak <uros@kss-loka.si> PR target/20421 diff --git a/gcc/tree-chrec.c b/gcc/tree-chrec.c index a360301..b6276e9 100644 --- a/gcc/tree-chrec.c +++ b/gcc/tree-chrec.c @@ -1002,7 +1002,23 @@ nb_vars_in_chrec (tree chrec) -/* Convert the initial condition of chrec to type. */ +/* Convert CHREC to TYPE. The following is rule is always true: + TREE_TYPE (chrec) == TREE_TYPE (CHREC_LEFT (chrec)) == TREE_TYPE + (CHREC_RIGHT (chrec)). An example of what could happen when adding + two chrecs and the type of the CHREC_RIGHT is different than + CHREC_LEFT is: + + {(uint) 0, +, (uchar) 10} + + {(uint) 0, +, (uchar) 250} + + that would produce a wrong result if CHREC_RIGHT is not (uint): + + {(uint) 0, +, (uchar) 4} + + instead of + + {(uint) 0, +, (uint) 260} +*/ tree chrec_convert (tree type, @@ -1037,6 +1053,18 @@ chrec_convert (tree type, TREE_OVERFLOW (res) = 0; if (CONSTANT_CLASS_P (res)) TREE_CONSTANT_OVERFLOW (res) = 0; + + /* But reject constants that don't fit in their type after conversion. + This can happen if TYPE_MIN_VALUE or TYPE_MAX_VALUE are not the + natural values associated with TYPE_PRECISION and TYPE_UNSIGNED, + and can cause problems later when computing niters of loops. Note + that we don't do the check before converting because we don't want + to reject conversions of negative chrecs to unsigned types. */ + if (TREE_CODE (res) == INTEGER_CST + && TREE_CODE (type) == INTEGER_TYPE + && !int_fits_type_p (res, type)) + res = chrec_dont_know; + return res; } } |