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| author | Marc Glisse <marc.glisse@inria.fr> | 2013-03-20 16:16:09 +0100 |
|---|---|---|
| committer | Marc Glisse <glisse@gcc.gnu.org> | 2013-03-20 15:16:09 +0000 |
| commit | 1fc5eced1bd73eef1975f803279b799f4b47c879 (patch) | |
| tree | c9c12c6936ec99c0dba644b250e5f40d506ee777 | |
| parent | 22c4c8694927961d5884eeab71a17b92aa4f9702 (diff) | |
| download | gcc-1fc5eced1bd73eef1975f803279b799f4b47c879.zip gcc-1fc5eced1bd73eef1975f803279b799f4b47c879.tar.gz gcc-1fc5eced1bd73eef1975f803279b799f4b47c879.tar.bz2 | |
re PR tree-optimization/56355 (abs and multiplication)
2013-03-20 Marc Glisse <marc.glisse@inria.fr>
PR tree-optimization/56355
gcc/
* fold-const.c (tree_binary_nonnegative_warnv_p) <MULT_EXPR>:
Also handle integers with undefined overflow.
gcc/testsuite/
* gcc.dg/pr56355-1.c: New file.
From-SVN: r196829
| -rw-r--r-- | gcc/ChangeLog | 6 | ||||
| -rw-r--r-- | gcc/fold-const.c | 19 | ||||
| -rw-r--r-- | gcc/testsuite/ChangeLog | 5 | ||||
| -rw-r--r-- | gcc/testsuite/gcc.dg/pr56355-1.c | 8 |
4 files changed, 30 insertions, 8 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 9873aca..1f4bb6d 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,9 @@ +2013-03-20 Marc Glisse <marc.glisse@inria.fr> + + PR tree-optimization/56355 + * fold-const.c (tree_binary_nonnegative_warnv_p) <MULT_EXPR>: + Also handle integers with undefined overflow. + 2013-03-20 Catherine Moore <clm@codesourcery.com> Maciej W. Rozycki <macro@codesourcery.com> Tom de Vries <tom@codesourcery.com> diff --git a/gcc/fold-const.c b/gcc/fold-const.c index de7117e..ae03938 100644 --- a/gcc/fold-const.c +++ b/gcc/fold-const.c @@ -15294,15 +15294,18 @@ tree_binary_nonnegative_warnv_p (enum tree_code code, tree type, tree op0, break; case MULT_EXPR: - if (FLOAT_TYPE_P (type)) + if (FLOAT_TYPE_P (type) || TYPE_OVERFLOW_UNDEFINED (type)) { - /* x * x for floating point x is always non-negative. */ - if (operand_equal_p (op0, op1, 0)) - return true; - return (tree_expr_nonnegative_warnv_p (op0, - strict_overflow_p) - && tree_expr_nonnegative_warnv_p (op1, - strict_overflow_p)); + /* x * x is always non-negative for floating point x + or without overflow. */ + if (operand_equal_p (op0, op1, 0) + || (tree_expr_nonnegative_warnv_p (op0, strict_overflow_p) + && tree_expr_nonnegative_warnv_p (op1, strict_overflow_p))) + { + if (TYPE_OVERFLOW_UNDEFINED (type)) + *strict_overflow_p = true; + return true; + } } /* zero_extend(x) * zero_extend(y) is non-negative if x and y are diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index a3f78a7..ef7bdd6 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2013-03-20 Marc Glisse <marc.glisse@inria.fr> + + PR tree-optimization/56355 + * gcc.dg/pr56355-1.c: New file. + 2013-03-20 Catherine Moore <clm@codesourcery.com> Richard Sandiford <rdsandiford@googlemail.com> diff --git a/gcc/testsuite/gcc.dg/pr56355-1.c b/gcc/testsuite/gcc.dg/pr56355-1.c new file mode 100644 index 0000000..08b9c2e --- /dev/null +++ b/gcc/testsuite/gcc.dg/pr56355-1.c @@ -0,0 +1,8 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -Wstrict-overflow=4" } */ + +int +f (int i) +{ + return __builtin_abs (i * i); /* { dg-warning "assuming signed overflow" } */ +} |