| Message ID | CAAe5K+XYPbX2SextpQvkShsa8ms-4DkzEVT8S38tVo9T2T9BUQ@mail.gmail.com |
|---|---|
| State | New |
| Headers | show |
On Thu, Nov 13, 2014 at 12:51:05PM -0800, Teresa Johnson wrote: > On Thu, Nov 13, 2014 at 7:39 AM, Teresa Johnson <tejohnson@google.com> wrote: > > On Thu, Nov 13, 2014 at 7:12 AM, Jakub Jelinek <jakub@redhat.com> wrote: > >> And for release branches I'd really prefer tree-ssa-strlen.c change. > > > > Ok, I started testing the initializer_zerop change on the 4_9 branch, > > will also test the strlen fix and send that patch for review here when > > it completes. > > Here is the more conservative patch for 4_9. Bootstrapped and tested > on x86_64-unknown-linux-gnu. Ok for gcc-4_9 branch? Ok, thanks. But I have a comment regarding the test below: > 2014-11-13 Teresa Johnson <tejohnson@google.com> > > gcc: > PR tree-optimization/63841 > * tree-ssa-strlen.c (strlen_optimize_stmt): Ignore clobbers. > > 2014-11-13 Teresa Johnson <tejohnson@google.com> > > gcc/testsuite: > PR tree-optimization/63841 > * testsuite/g++.dg/tree-ssa/pr63841.C: New test. > > Index: tree-ssa-strlen.c > =================================================================== > --- tree-ssa-strlen.c (revision 217503) > +++ tree-ssa-strlen.c (working copy) > @@ -1856,7 +1856,7 @@ strlen_optimize_stmt (gimple_stmt_iterator *gsi) > break; > } > } > - else if (is_gimple_assign (stmt)) > + else if (is_gimple_assign (stmt) && !gimple_clobber_p (stmt)) > { > tree lhs = gimple_assign_lhs (stmt); > > Index: testsuite/g++.dg/tree-ssa/pr63841.C > =================================================================== > --- testsuite/g++.dg/tree-ssa/pr63841.C (revision 0) > +++ testsuite/g++.dg/tree-ssa/pr63841.C (working copy) > @@ -0,0 +1,38 @@ > +/* { dg-do run } */ > +/* { dg-options "-O2" } */ > + > +#include <cstdio> > +#include <string> > + > +std::string __attribute__ ((noinline)) comp_test_write() { > + std::string data; > + > + for (int i = 0; i < 2; ++i) { > + char b = 1 >> (i * 8); > + data.append(&b, 1); > + } > + > + return data; > +} > + > +std::string __attribute__ ((noinline)) comp_test_write_good() { > + std::string data; > + > + char b; > + for (int i = 0; i < 2; ++i) { > + b = 1 >> (i * 8); > + data.append(&b, 1); > + } > + > + return data; > +} > + > +int main() { > + std::string good = comp_test_write_good(); > + printf("expected: %hx\n", *(short*)good.c_str()); > + > + std::string bad = comp_test_write(); > + printf("got: %hx\n", *(short*)bad.c_str()); Supposedly the printfs should have been removed and the #include <cstdio> isn't needed then either. No need to clutter the test output and log files. On the other side, tests should abort (); or __builtin_abort (); on failure, not just return non-zero. > + > + return good != bad; > +} Jakub
Index: tree-ssa-strlen.c =================================================================== --- tree-ssa-strlen.c (revision 217503) +++ tree-ssa-strlen.c (working copy) @@ -1856,7 +1856,7 @@ strlen_optimize_stmt (gimple_stmt_iterator *gsi) break; } } - else if (is_gimple_assign (stmt)) + else if (is_gimple_assign (stmt) && !gimple_clobber_p (stmt)) { tree lhs = gimple_assign_lhs (stmt); Index: testsuite/g++.dg/tree-ssa/pr63841.C =================================================================== --- testsuite/g++.dg/tree-ssa/pr63841.C (revision 0) +++ testsuite/g++.dg/tree-ssa/pr63841.C (working copy) @@ -0,0 +1,38 @@ +/* { dg-do run } */ +/* { dg-options "-O2" } */ + +#include <cstdio> +#include <string> + +std::string __attribute__ ((noinline)) comp_test_write() { + std::string data; + + for (int i = 0; i < 2; ++i) { + char b = 1 >> (i * 8); + data.append(&b, 1); + } + + return data; +} + +std::string __attribute__ ((noinline)) comp_test_write_good() { + std::string data; + + char b; + for (int i = 0; i < 2; ++i) { + b = 1 >> (i * 8); + data.append(&b, 1); + } + + return data; +} + +int main() { + std::string good = comp_test_write_good(); + printf("expected: %hx\n", *(short*)good.c_str()); + + std::string bad = comp_test_write(); + printf("got: %hx\n", *(short*)bad.c_str()); + + return good != bad; +}