| Message ID | CACgzC7AboXhrnJEcssAtnWFQryTn3zzKW=LVH3PgwDp8+gHeQg@mail.gmail.com |
|---|---|
| State | New |
| Headers | show |
On 20 Sep 2012, at 08:51, "Zhenqiang Chen" <zhenqiang.chen@linaro.org> wrote: > Hi, > > PR 50970 is a general c++ front-end issue for targets which define > TARGET_PTRMEMFUNC_VBIT_LOCATION ptrmemfunc_vbit_in_delta, although the > reporter had issues only on ARM. > > Root cause: It misses a check for side effects when generating pfn and > delta related expressions. > > In the failed case, op0 is a function call. pfn0 and delta0 are > expressions based on the return value of op0. Without the check, the > function will be called twice. > > The patch is to add the check for op0. > > No make check regression on ARM. > > Is it OK for trunk? > > Thanks! > -Zhenqiang > > cp/ChangeLog: > 2012-09-20 Zhenqiang Chen <zhenqiang.chen@linaro.org> > > PR c++/50970 > * typeck.c (cp_build_binary_op): Check side effects before generating > pfn and delta related expressions. > Ok. R. > diff --git a/gcc/cp/typeck.c b/gcc/cp/typeck.c > index ad4b090..884f7d0 100644 > --- a/gcc/cp/typeck.c > +++ b/gcc/cp/typeck.c > @@ -4159,18 +4159,23 @@ cp_build_binary_op (location_t location, > if (TARGET_PTRMEMFUNC_VBIT_LOCATION > == ptrmemfunc_vbit_in_delta) > { > - tree pfn0 = pfn_from_ptrmemfunc (op0); > - tree delta0 = delta_from_ptrmemfunc (op0); > - tree e1 = cp_build_binary_op (location, > - EQ_EXPR, > - pfn0, > - build_zero_cst (TREE_TYPE (pfn0)), > - complain); > - tree e2 = cp_build_binary_op (location, > - BIT_AND_EXPR, > - delta0, > - integer_one_node, > - complain); > + tree pfn0, delta0, e1, e2; > + > + if (TREE_SIDE_EFFECTS (op0)) > + op0 = save_expr (op0); > + > + pfn0 = pfn_from_ptrmemfunc (op0); > + delta0 = delta_from_ptrmemfunc (op0); > + e1 = cp_build_binary_op (location, > + EQ_EXPR, > + pfn0, > + build_zero_cst (TREE_TYPE (pfn0)), > + complain); > + e2 = cp_build_binary_op (location, > + BIT_AND_EXPR, > + delta0, > + integer_one_node, > + complain); > > if ((complain & tf_warning) > && c_inhibit_evaluation_warnings == 0 >
On 22 September 2012 06:42, <rearnsha@arm.com> wrote: > On 20 Sep 2012, at 08:51, "Zhenqiang Chen" <zhenqiang.chen@linaro.org> wrote: > >> Hi, >> >> PR 50970 is a general c++ front-end issue for targets which define >> TARGET_PTRMEMFUNC_VBIT_LOCATION ptrmemfunc_vbit_in_delta, although the >> reporter had issues only on ARM. >> >> Root cause: It misses a check for side effects when generating pfn and >> delta related expressions. >> >> In the failed case, op0 is a function call. pfn0 and delta0 are >> expressions based on the return value of op0. Without the check, the >> function will be called twice. >> >> The patch is to add the check for op0. >> >> No make check regression on ARM. >> >> Is it OK for trunk? >> >> Thanks! >> -Zhenqiang >> >> cp/ChangeLog: >> 2012-09-20 Zhenqiang Chen <zhenqiang.chen@linaro.org> >> >> PR c++/50970 >> * typeck.c (cp_build_binary_op): Check side effects before generating >> pfn and delta related expressions. >> > > Ok. > > R. Thanks, committed to trunk. The bug also happens in FSF 4.7. Can I backport it to 4.7? Thanks! -Zhenqiang >> diff --git a/gcc/cp/typeck.c b/gcc/cp/typeck.c >> index ad4b090..884f7d0 100644 >> --- a/gcc/cp/typeck.c >> +++ b/gcc/cp/typeck.c >> @@ -4159,18 +4159,23 @@ cp_build_binary_op (location_t location, >> if (TARGET_PTRMEMFUNC_VBIT_LOCATION >> == ptrmemfunc_vbit_in_delta) >> { >> - tree pfn0 = pfn_from_ptrmemfunc (op0); >> - tree delta0 = delta_from_ptrmemfunc (op0); >> - tree e1 = cp_build_binary_op (location, >> - EQ_EXPR, >> - pfn0, >> - build_zero_cst (TREE_TYPE (pfn0)), >> - complain); >> - tree e2 = cp_build_binary_op (location, >> - BIT_AND_EXPR, >> - delta0, >> - integer_one_node, >> - complain); >> + tree pfn0, delta0, e1, e2; >> + >> + if (TREE_SIDE_EFFECTS (op0)) >> + op0 = save_expr (op0); >> + >> + pfn0 = pfn_from_ptrmemfunc (op0); >> + delta0 = delta_from_ptrmemfunc (op0); >> + e1 = cp_build_binary_op (location, >> + EQ_EXPR, >> + pfn0, >> + build_zero_cst (TREE_TYPE (pfn0)), >> + complain); >> + e2 = cp_build_binary_op (location, >> + BIT_AND_EXPR, >> + delta0, >> + integer_one_node, >> + complain); >> >> if ((complain & tf_warning) >> && c_inhibit_evaluation_warnings == 0 >> >
diff --git a/gcc/cp/typeck.c b/gcc/cp/typeck.c index ad4b090..884f7d0 100644 --- a/gcc/cp/typeck.c +++ b/gcc/cp/typeck.c @@ -4159,18 +4159,23 @@ cp_build_binary_op (location_t location, if (TARGET_PTRMEMFUNC_VBIT_LOCATION == ptrmemfunc_vbit_in_delta) { - tree pfn0 = pfn_from_ptrmemfunc (op0); - tree delta0 = delta_from_ptrmemfunc (op0); - tree e1 = cp_build_binary_op (location, - EQ_EXPR, - pfn0, - build_zero_cst (TREE_TYPE (pfn0)), - complain); - tree e2 = cp_build_binary_op (location, - BIT_AND_EXPR, - delta0, - integer_one_node, - complain); + tree pfn0, delta0, e1, e2; + + if (TREE_SIDE_EFFECTS (op0)) + op0 = save_expr (op0); + + pfn0 = pfn_from_ptrmemfunc (op0); + delta0 = delta_from_ptrmemfunc (op0); + e1 = cp_build_binary_op (location, + EQ_EXPR, + pfn0, + build_zero_cst (TREE_TYPE (pfn0)), + complain); + e2 = cp_build_binary_op (location, + BIT_AND_EXPR, + delta0, + integer_one_node, + complain); if ((complain & tf_warning) && c_inhibit_evaluation_warnings == 0