diff options
| -rw-r--r-- | gcc/ChangeLog | 11 | ||||
| -rw-r--r-- | gcc/testsuite/ChangeLog | 6 | ||||
| -rw-r--r-- | gcc/testsuite/c-c++-common/guality/Og-dce-1.c | 14 | ||||
| -rw-r--r-- | gcc/testsuite/c-c++-common/guality/Og-dce-2.c | 19 | ||||
| -rw-r--r-- | gcc/testsuite/c-c++-common/guality/Og-dce-3.c | 29 | ||||
| -rw-r--r-- | gcc/tree-ssa-dce.c | 23 |
6 files changed, 102 insertions, 0 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 3e84baf..8cd321e 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,5 +1,16 @@ 2019-07-29 Richard Sandiford <richard.sandiford@arm.com> + PR debug/86638 + * tree-ssa-dce.c (keep_all_vdefs_p): New function. + (mark_stmt_if_obviously_necessary): Mark all stmts with vdefs as + necessary if keep_all_vdefs_p is true. + (mark_aliased_reaching_defs_necessary): Add a gcc_checking_assert + that keep_all_vdefs_p is false. + (mark_all_reaching_defs_necessary): Likewise. + (propagate_necessity): Skip the vuse scan if keep_all_vdefs_p is true. + +2019-07-29 Richard Sandiford <richard.sandiford@arm.com> + * common.opt (Og): Change the initial value of flag_dse to 0. * opts.c (default_options_table): Move OPT_ftree_dse from OPT_LEVELS_1_PLUS to OPT_LEVELS_1_PLUS_NOT_DEBUG. Also add diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 6dab451..cc1aadf 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,5 +1,11 @@ 2019-07-29 Richard Sandiford <richard.sandiford@arm.com> + * c-c++-common/guality/Og-dce-1.c: New test. + * c-c++-common/guality/Og-dce-2.c: Likewise. + * c-c++-common/guality/Og-dce-3.c: Likewise. + +2019-07-29 Richard Sandiford <richard.sandiford@arm.com> + * c-c++-common/guality/Og-global-dse-1.c: New test. 2019-07-29 Richard Sandiford <richard.sandiford@arm.com> diff --git a/gcc/testsuite/c-c++-common/guality/Og-dce-1.c b/gcc/testsuite/c-c++-common/guality/Og-dce-1.c new file mode 100644 index 0000000..a859e32 --- /dev/null +++ b/gcc/testsuite/c-c++-common/guality/Og-dce-1.c @@ -0,0 +1,14 @@ +/* { dg-do run } */ +/* { dg-options "-g" } */ + +int *__attribute__((noipa)) consume (int *ptr) { return ptr; } + +int +main (void) +{ + int x; + int *volatile ptr = consume (&x); + x = 0; + x = 1; /* { dg-final { gdb-test . "*ptr" "0" } } */ + return 0; /* { dg-final { gdb-test . "*ptr" "1" } } */ +} diff --git a/gcc/testsuite/c-c++-common/guality/Og-dce-2.c b/gcc/testsuite/c-c++-common/guality/Og-dce-2.c new file mode 100644 index 0000000..3df2c79 --- /dev/null +++ b/gcc/testsuite/c-c++-common/guality/Og-dce-2.c @@ -0,0 +1,19 @@ +/* { dg-do run } */ +/* { dg-options "-g" } */ + +struct s { int a, b, c, d; }; + +struct s gs1 = { 1, 2, 3, 4 }; +struct s gs2 = { 5, 6, 7, 8 }; + +struct s *__attribute__((noipa)) consume (struct s *ptr) { return ptr; } + +int +main (void) +{ + struct s x; + struct s *volatile ptr = consume (&x); + x = gs1; + x = gs2; /* { dg-final { gdb-test . "ptr->a" "1" } } */ + return 0; /* { dg-final { gdb-test . "ptr->a" "5" } } */ +} diff --git a/gcc/testsuite/c-c++-common/guality/Og-dce-3.c b/gcc/testsuite/c-c++-common/guality/Og-dce-3.c new file mode 100644 index 0000000..fa6186a --- /dev/null +++ b/gcc/testsuite/c-c++-common/guality/Og-dce-3.c @@ -0,0 +1,29 @@ +/* { dg-do run } */ +/* { dg-options "-g" } */ + +volatile int amount = 10; + +void __attribute__((noipa)) +do_something (int *ptr) +{ + *ptr += 10; +} + +int __attribute__((noipa)) +foo (int count) +{ + int x = 1; + for (int i = 0; i < count; ++i) + do_something (&x); /* { dg-final { gdb-test . "x" "1" } } */ + int res = x; /* { dg-final { gdb-test . "x" "101" } } */ + x = res + 1; + return res; /* { dg-final { gdb-test . "x" "102" } } */ + +} + +int +main (void) +{ + foo (10); + return 0; +} diff --git a/gcc/tree-ssa-dce.c b/gcc/tree-ssa-dce.c index 90b3f4d..17a8d5e 100644 --- a/gcc/tree-ssa-dce.c +++ b/gcc/tree-ssa-dce.c @@ -115,6 +115,14 @@ static bool cfg_altered; static int *bb_postorder; +/* True if we should treat any stmt with a vdef as necessary. */ + +static inline bool +keep_all_vdefs_p () +{ + return optimize_debug; +} + /* If STMT is not already marked necessary, mark it, and add it to the worklist if ADD_TO_WORKLIST is true. */ @@ -317,6 +325,12 @@ mark_stmt_if_obviously_necessary (gimple *stmt, bool aggressive) return; } + if (gimple_vdef (stmt) && keep_all_vdefs_p ()) + { + mark_stmt_necessary (stmt, true); + return; + } + return; } @@ -532,6 +546,9 @@ mark_aliased_reaching_defs_necessary_1 (ao_ref *ref, tree vdef, void *data) static void mark_aliased_reaching_defs_necessary (gimple *stmt, tree ref) { + /* Should have been caught before calling this function. */ + gcc_checking_assert (!keep_all_vdefs_p ()); + unsigned int chain; ao_ref refd; gcc_assert (!chain_ovfl); @@ -610,6 +627,8 @@ mark_all_reaching_defs_necessary_1 (ao_ref *ref ATTRIBUTE_UNUSED, static void mark_all_reaching_defs_necessary (gimple *stmt) { + /* Should have been caught before calling this function. */ + gcc_checking_assert (!keep_all_vdefs_p ()); walk_aliased_vdefs (NULL, gimple_vuse (stmt), mark_all_reaching_defs_necessary_1, NULL, &visited); } @@ -813,6 +832,10 @@ propagate_necessity (bool aggressive) if (!use) continue; + /* No need to search for vdefs if we intrinsicly keep them all. */ + if (keep_all_vdefs_p ()) + continue; + /* If we dropped to simple mode make all immediately reachable definitions necessary. */ if (chain_ovfl) |