| Message ID | 20110615185701.GL17079@tyan-ft48-01.lab.bos.redhat.com |
|---|---|
| State | New |
| Headers | show |
On Wed, Jun 15, 2011 at 8:57 PM, Jakub Jelinek <jakub@redhat.com> wrote: > Hi! > > The following testcase is miscompiled e.g. on powerpc (not on x86_64/i686 > due to different ivopts choices), because estimate_numbers_of_iterations > was called before assert_exprs are added to the IL and gets info cached > until adjust_range_with_scev, where using the original SSA_NAMEs leads > to problems where VR changes might not be propagated properly. > > Fixed thusly, bootstrapped/regtested on x86_64-linux and i686-linux, > ok for trunk/4.6? I'll work on followup improvements for the trunk > afterwards. Ok. Thanks, Richard. > 2011-06-15 Jakub Jelinek <jakub@redhat.com> > > PR tree-optimization/49419 > * tree-vrp.c (execute_vrp): Call init_range_assertions > before estimate_numbers_of_iterations, call > free_number_of_iterations_estimates before calling > remove_range_assertions. > > * gcc.c-torture/execute/pr49419.c: New test. > > --- gcc/tree-vrp.c.jj 2011-05-31 08:03:10.000000000 +0200 > +++ gcc/tree-vrp.c 2011-06-15 17:25:32.000000000 +0200 > @@ -7730,14 +7730,14 @@ execute_vrp (void) > rewrite_into_loop_closed_ssa (NULL, TODO_update_ssa); > scev_initialize (); > > + insert_range_assertions (); > + > /* Estimate number of iterations - but do not use undefined behavior > for this. We can't do this lazily as other functions may compute > this using undefined behavior. */ > free_numbers_of_iterations_estimates (); > estimate_numbers_of_iterations (false); > > - insert_range_assertions (); > - > to_remove_edges = VEC_alloc (edge, heap, 10); > to_update_switch_stmts = VEC_alloc (switch_update, heap, 5); > threadedge_initialize_values (); > @@ -7746,6 +7746,8 @@ execute_vrp (void) > ssa_propagate (vrp_visit_stmt, vrp_visit_phi_node); > vrp_finalize (); > > + free_numbers_of_iterations_estimates (); > + > /* ASSERT_EXPRs must be removed before finalizing jump threads > as finalizing jump threads calls the CFG cleanup code which > does not properly handle ASSERT_EXPRs. */ > --- gcc/testsuite/gcc.c-torture/execute/pr49419.c.jj 2011-06-15 18:06:43.000000000 +0200 > +++ gcc/testsuite/gcc.c-torture/execute/pr49419.c 2011-06-15 18:05:18.000000000 +0200 > @@ -0,0 +1,38 @@ > +/* PR tree-optimization/49419 */ > + > +extern void abort (void); > + > +struct S { int w, x, y; } *t; > + > +int > +foo (int n, int f, int *s, int m) > +{ > + int x, i, a; > + if (n == -1) > + return 0; > + for (x = n, i = 0; t[x].w == f && i < m; i++) > + x = t[x].x; > + if (i == m) > + abort (); > + a = i + 1; > + for (x = n; i > 0; i--) > + { > + s[i] = t[x].y; > + x = t[x].x; > + } > + s[0] = x; > + return a; > +} > + > +int > +main (void) > +{ > + int s[3], i; > + struct S buf[3] = { { 1, 1, 2 }, { 0, 0, 0 }, { 0, 0, 0 } }; > + t = buf; > + if (foo (0, 1, s, 3) != 2) > + abort (); > + if (s[0] != 1 || s[1] != 2) > + abort (); > + return 0; > +} > > Jakub >
--- gcc/tree-vrp.c.jj 2011-05-31 08:03:10.000000000 +0200 +++ gcc/tree-vrp.c 2011-06-15 17:25:32.000000000 +0200 @@ -7730,14 +7730,14 @@ execute_vrp (void) rewrite_into_loop_closed_ssa (NULL, TODO_update_ssa); scev_initialize (); + insert_range_assertions (); + /* Estimate number of iterations - but do not use undefined behavior for this. We can't do this lazily as other functions may compute this using undefined behavior. */ free_numbers_of_iterations_estimates (); estimate_numbers_of_iterations (false); - insert_range_assertions (); - to_remove_edges = VEC_alloc (edge, heap, 10); to_update_switch_stmts = VEC_alloc (switch_update, heap, 5); threadedge_initialize_values (); @@ -7746,6 +7746,8 @@ execute_vrp (void) ssa_propagate (vrp_visit_stmt, vrp_visit_phi_node); vrp_finalize (); + free_numbers_of_iterations_estimates (); + /* ASSERT_EXPRs must be removed before finalizing jump threads as finalizing jump threads calls the CFG cleanup code which does not properly handle ASSERT_EXPRs. */ --- gcc/testsuite/gcc.c-torture/execute/pr49419.c.jj 2011-06-15 18:06:43.000000000 +0200 +++ gcc/testsuite/gcc.c-torture/execute/pr49419.c 2011-06-15 18:05:18.000000000 +0200 @@ -0,0 +1,38 @@ +/* PR tree-optimization/49419 */ + +extern void abort (void); + +struct S { int w, x, y; } *t; + +int +foo (int n, int f, int *s, int m) +{ + int x, i, a; + if (n == -1) + return 0; + for (x = n, i = 0; t[x].w == f && i < m; i++) + x = t[x].x; + if (i == m) + abort (); + a = i + 1; + for (x = n; i > 0; i--) + { + s[i] = t[x].y; + x = t[x].x; + } + s[0] = x; + return a; +} + +int +main (void) +{ + int s[3], i; + struct S buf[3] = { { 1, 1, 2 }, { 0, 0, 0 }, { 0, 0, 0 } }; + t = buf; + if (foo (0, 1, s, 3) != 2) + abort (); + if (s[0] != 1 || s[1] != 2) + abort (); + return 0; +}