| Message ID | Y5RT+ZOKX3pHseJu@tucnak |
|---|---|
| State | New |
| Headers | show |
| Series | ivopts: Fix IP_END handling for asm goto [PR107997] | expand |
> Am 10.12.2022 um 10:40 schrieb Jakub Jelinek via Gcc-patches <gcc-patches@gcc.gnu.org>: > > Hi! > > The following testcase ICEs, because the latch bb ends with > asm goto which has both fallthrough to the header and one or more labels > in the header too. In that case there is just a single edge out of the > latch block, but still the asm goto is stmt_ends_bb_p statement, yet > ivopts decides to emit an IV bump at the IP_END position and inserts > it into the same bb as the asm goto after it, which then fails verification > (control flow in the middle of bb). > > The following patch fixes it by splitting the latch -> header edge in that > case and inserting into the newly created bb, where split_edge -> > redirect_edge_and_branch is able to deal with this case correctly. > > Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk? Ok, Richard > 2022-12-10 Jakub Jelinek <jakub@redhat.com> > > PR tree-optimization/107997 > * tree-ssa-loop-ivopts.cc: Include cfganal.h. > (create_new_iv) <case IP_END>: If ip_end_pos bb is non-empty and ends > with a stmt which ends bb, instead of adding iv update after it split > the latch edge and insert iterator into the new latch bb. > > * gcc.c-torture/compile/pr107997.c: New test. > > --- gcc/tree-ssa-loop-ivopts.cc.jj 2022-12-05 11:10:37.786670489 +0100 > +++ gcc/tree-ssa-loop-ivopts.cc 2022-12-09 14:42:24.722896379 +0100 > @@ -131,6 +131,7 @@ along with GCC; see the file COPYING3. > #include "builtins.h" > #include "tree-vectorizer.h" > #include "dbgcnt.h" > +#include "cfganal.h" > > /* For lang_hooks.types.type_for_mode. */ > #include "langhooks.h" > @@ -7235,6 +7236,12 @@ create_new_iv (struct ivopts_data *data, > case IP_END: > incr_pos = gsi_last_bb (ip_end_pos (data->current_loop)); > after = true; > + if (!gsi_end_p (incr_pos) && stmt_ends_bb_p (gsi_stmt (incr_pos))) > + { > + edge e = find_edge (gsi_bb (incr_pos), data->current_loop->header); > + incr_pos = gsi_after_labels (split_edge (e)); > + after = false; > + } > break; > > case IP_AFTER_USE: > --- gcc/testsuite/gcc.c-torture/compile/pr107997.c.jj 2022-12-09 14:45:29.458160841 +0100 > +++ gcc/testsuite/gcc.c-torture/compile/pr107997.c 2022-12-09 14:45:12.290415073 +0100 > @@ -0,0 +1,23 @@ > +/* PR tree-optimization/107997 */ > + > +int a, b; > +void bar (int); > +int baz (void); > + > +void * > +foo (int x, void *y) > +{ > + asm goto ("" : : "r" (x || !a) : : l); > +l: > + if (y) > + return 0; > + bar (b ? b : x); > + while (x--) > + { > + if (!baz ()) > + baz (); > + asm goto ("" : : : : l2); > + l2:; > + } > + return y; > +} > > Jakub >
--- gcc/tree-ssa-loop-ivopts.cc.jj 2022-12-05 11:10:37.786670489 +0100 +++ gcc/tree-ssa-loop-ivopts.cc 2022-12-09 14:42:24.722896379 +0100 @@ -131,6 +131,7 @@ along with GCC; see the file COPYING3. #include "builtins.h" #include "tree-vectorizer.h" #include "dbgcnt.h" +#include "cfganal.h" /* For lang_hooks.types.type_for_mode. */ #include "langhooks.h" @@ -7235,6 +7236,12 @@ create_new_iv (struct ivopts_data *data, case IP_END: incr_pos = gsi_last_bb (ip_end_pos (data->current_loop)); after = true; + if (!gsi_end_p (incr_pos) && stmt_ends_bb_p (gsi_stmt (incr_pos))) + { + edge e = find_edge (gsi_bb (incr_pos), data->current_loop->header); + incr_pos = gsi_after_labels (split_edge (e)); + after = false; + } break; case IP_AFTER_USE: --- gcc/testsuite/gcc.c-torture/compile/pr107997.c.jj 2022-12-09 14:45:29.458160841 +0100 +++ gcc/testsuite/gcc.c-torture/compile/pr107997.c 2022-12-09 14:45:12.290415073 +0100 @@ -0,0 +1,23 @@ +/* PR tree-optimization/107997 */ + +int a, b; +void bar (int); +int baz (void); + +void * +foo (int x, void *y) +{ + asm goto ("" : : "r" (x || !a) : : l); +l: + if (y) + return 0; + bar (b ? b : x); + while (x--) + { + if (!baz ()) + baz (); + asm goto ("" : : : : l2); + l2:; + } + return y; +}