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| author | Richard Henderson <rth@cygnus.com> | 2000-07-15 10:22:26 -0700 |
|---|---|---|
| committer | Richard Henderson <rth@gcc.gnu.org> | 2000-07-15 10:22:26 -0700 |
| commit | eff9c80d3e2e37092e65e7cdad5e3e18b027c860 (patch) | |
| tree | e5579d53bbfd68cc1b545093e50c591a58f7e5da /gcc | |
| parent | b27ca4d10ba6ce5966aa6e4b01966bcdc43a3181 (diff) | |
| download | gcc-eff9c80d3e2e37092e65e7cdad5e3e18b027c860.zip gcc-eff9c80d3e2e37092e65e7cdad5e3e18b027c860.tar.gz gcc-eff9c80d3e2e37092e65e7cdad5e3e18b027c860.tar.bz2 | |
fold-const.c (extract_muldiv): Don't optimize past an unsigned cast around an expression.
* fold-const.c (extract_muldiv): Don't optimize past an unsigned
cast around an expression. Tidy other unsigned tests.
From-SVN: r35049
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ChangeLog | 5 | ||||
| -rw-r--r-- | gcc/fold-const.c | 17 |
2 files changed, 19 insertions, 3 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index b428538..77a6af1 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,8 @@ +2000-07-15 Richard Henderson <rth@cygnus.com> + + * fold-const.c (extract_muldiv): Don't optimize past an unsigned + cast around an expression. Tidy other unsigned tests. + 2000-07-15 Gabriel Dos Reis <gdr@codesourcery.com> * diagnostic.c (doing_line_wrapping, line_wrapper_printf, notice, diff --git a/gcc/fold-const.c b/gcc/fold-const.c index f259115..c636bdc 100644 --- a/gcc/fold-const.c +++ b/gcc/fold-const.c @@ -4397,6 +4397,18 @@ extract_muldiv (t, c, code, wide_type) break; case CONVERT_EXPR: case NON_LVALUE_EXPR: case NOP_EXPR: + /* If op0 is an expression, and is unsigned, and the type is + smaller than ctype, then we cannot widen the expression. */ + if ((TREE_CODE_CLASS (TREE_CODE (op0)) == '<' + || TREE_CODE_CLASS (TREE_CODE (op0)) == '1' + || TREE_CODE_CLASS (TREE_CODE (op0)) == '2' + || TREE_CODE_CLASS (TREE_CODE (op0)) == 'e') + && TREE_UNSIGNED (TREE_TYPE (op0)) + && ! TYPE_IS_SIZETYPE (TREE_TYPE (op0)) + && (GET_MODE_SIZE (TYPE_MODE (ctype)) + > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0))))) + break; + /* Pass the constant down and see if we can make a simplification. If we can, replace this expression with the inner simplification for possible later conversion to our or some other type. */ @@ -4413,7 +4425,7 @@ extract_muldiv (t, c, code, wide_type) case MIN_EXPR: case MAX_EXPR: /* If widening the type changes the signedness, then we can't perform this optimization as that changes the result. */ - if (ctype != type && TREE_UNSIGNED (ctype) != TREE_UNSIGNED (type)) + if (TREE_UNSIGNED (ctype) != TREE_UNSIGNED (type)) break; /* MIN (a, b) / 5 -> MIN (a / 5, b / 5) */ @@ -4581,8 +4593,7 @@ extract_muldiv (t, c, code, wide_type) this since it will change the result if the original computation overflowed. */ if ((! TREE_UNSIGNED (ctype) - || (TREE_CODE (ctype) == INTEGER_TYPE - && TYPE_IS_SIZETYPE (ctype))) + || TYPE_IS_SIZETYPE (ctype)) && ((code == MULT_EXPR && tcode == EXACT_DIV_EXPR) || (tcode == MULT_EXPR && code != TRUNC_MOD_EXPR && code != CEIL_MOD_EXPR |