| Message ID | 20180206203555.GD5867@tucnak |
|---|---|
| State | New |
| Headers | show |
| Series | Small -ftrapv improvement | expand |
On Tue, 6 Feb 2018, Jakub Jelinek wrote: > Hi! > > As mentioned on IRC, operation_could_trap_helper_p returns true > for division or modulo with -ftrapv; the operations could trap in certain > cases (e.g. division by -1 of minimum signed value, but we don't have any > library functions for division/modulo for -ftrapv nor instrument it in any > way). The following just makes it match what we implement. > > Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk? Ok. Thanks, Richard. > 2018-02-06 Jakub Jelinek <jakub@redhat.com> > > * tree-eh.c (operation_could_trap_helper_p): Ignore honor_trapv for > *DIV_EXPR and *MOD_EXPR. > > --- gcc/tree-eh.c.jj 2018-02-01 11:07:24.000000000 +0100 > +++ gcc/tree-eh.c 2018-02-03 17:52:40.573255559 +0100 > @@ -2436,7 +2436,7 @@ operation_could_trap_helper_p (enum tree > case ROUND_MOD_EXPR: > case TRUNC_MOD_EXPR: > case RDIV_EXPR: > - if (honor_snans || honor_trapv) > + if (honor_snans) > return true; > if (fp_operation) > return flag_trapping_math; > > Jakub > >
--- gcc/tree-eh.c.jj 2018-02-01 11:07:24.000000000 +0100 +++ gcc/tree-eh.c 2018-02-03 17:52:40.573255559 +0100 @@ -2436,7 +2436,7 @@ operation_could_trap_helper_p (enum tree case ROUND_MOD_EXPR: case TRUNC_MOD_EXPR: case RDIV_EXPR: - if (honor_snans || honor_trapv) + if (honor_snans) return true; if (fp_operation) return flag_trapping_math;