From: Martin Jambor Date: Thu, 4 Jun 2020 15:03:27 +0000 (+0200) Subject: ipa-sra: Do not remove statements necessary because of non-call EH (PR 95113) X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=1980ffec48c6fa41396bea66366f2e591798e1e1;p=gcc.git ipa-sra: Do not remove statements necessary because of non-call EH (PR 95113) PR 95113 revealed that when reasoning about which parameters are dead, IPA-SRA does not perform the same check related to non-call exceptions as tree DCE. It most certainly should and so this patch moves the condition used in tree-ssa-dce.c into a separate predicate (in tree-eh.c) and uses it from both places. gcc/ChangeLog: 2020-05-27 Martin Jambor PR ipa/95113 * tree-ssa-dce.c (mark_stmt_if_obviously_necessary): Move non-call exceptions check to... * tree-eh.c (stmt_unremovable_because_of_non_call_eh_p): ...this new function. * tree-eh.h (stmt_unremovable_because_of_non_call_eh_p): Declare it. * ipa-sra.c (isra_track_scalar_value_uses): Use it. New parameter fun. gcc/testsuite/ChangeLog: 2020-05-27 Martin Jambor PR ipa/95113 * gcc.dg/ipa/pr95113.c: New test. --- diff --git a/gcc/ipa-sra.c b/gcc/ipa-sra.c index 7c922e40a4e..c81e8869e7a 100644 --- a/gcc/ipa-sra.c +++ b/gcc/ipa-sra.c @@ -795,17 +795,17 @@ get_single_param_flow_source (const isra_param_flow *param_flow) } /* Inspect all uses of NAME and simple arithmetic calculations involving NAME - in NODE and return a negative number if any of them is used for something - else than either an actual call argument, simple arithmetic operation or - debug statement. If there are no such uses, return the number of actual - arguments that this parameter eventually feeds to (or zero if there is none). - For any such parameter, mark PARM_NUM as one of its sources. ANALYZED is a - bitmap that tracks which SSA names we have already started - investigating. */ + in FUN represented with NODE and return a negative number if any of them is + used for something else than either an actual call argument, simple + arithmetic operation or debug statement. If there are no such uses, return + the number of actual arguments that this parameter eventually feeds to (or + zero if there is none). For any such parameter, mark PARM_NUM as one of its + sources. ANALYZED is a bitmap that tracks which SSA names we have already + started investigating. */ static int -isra_track_scalar_value_uses (cgraph_node *node, tree name, int parm_num, - bitmap analyzed) +isra_track_scalar_value_uses (function *fun, cgraph_node *node, tree name, + int parm_num, bitmap analyzed) { int res = 0; imm_use_iterator imm_iter; @@ -859,8 +859,9 @@ isra_track_scalar_value_uses (cgraph_node *node, tree name, int parm_num, } res += all_uses; } - else if ((is_gimple_assign (stmt) && !gimple_has_volatile_ops (stmt)) - || gimple_code (stmt) == GIMPLE_PHI) + else if (!stmt_unremovable_because_of_non_call_eh_p (fun, stmt) + && ((is_gimple_assign (stmt) && !gimple_has_volatile_ops (stmt)) + || gimple_code (stmt) == GIMPLE_PHI)) { tree lhs; if (gimple_code (stmt) == GIMPLE_PHI) @@ -876,7 +877,7 @@ isra_track_scalar_value_uses (cgraph_node *node, tree name, int parm_num, gcc_assert (!gimple_vdef (stmt)); if (bitmap_set_bit (analyzed, SSA_NAME_VERSION (lhs))) { - int tmp = isra_track_scalar_value_uses (node, lhs, parm_num, + int tmp = isra_track_scalar_value_uses (fun, node, lhs, parm_num, analyzed); if (tmp < 0) { @@ -927,7 +928,8 @@ isra_track_scalar_param_local_uses (function *fun, cgraph_node *node, tree parm, return true; bitmap analyzed = BITMAP_ALLOC (NULL); - int call_uses = isra_track_scalar_value_uses (node, name, parm_num, analyzed); + int call_uses = isra_track_scalar_value_uses (fun, node, name, parm_num, + analyzed); BITMAP_FREE (analyzed); if (call_uses < 0) return true; diff --git a/gcc/testsuite/gcc.dg/ipa/pr95113.c b/gcc/testsuite/gcc.dg/ipa/pr95113.c new file mode 100644 index 00000000000..a8f8c901ebe --- /dev/null +++ b/gcc/testsuite/gcc.dg/ipa/pr95113.c @@ -0,0 +1,33 @@ +/* { dg-do run } */ +/* { dg-options "-O2 -fexceptions -fnon-call-exceptions" } */ +/* { dg-require-effective-target exceptions } */ + +int a, b; + +static inline long int +foo (long int x, int y) +{ + if (y == 0) + return 0; + + if (x == -1 && y == -1) + return 0; + + return x / y; +} + +static inline int +bar (int *p) +{ + int c = foo (a, 1) + *p; + return b; +} + +int +main () +{ + int d = 0; + b = foo (1, 1); + bar (&d); + return 0; +} diff --git a/gcc/tree-eh.c b/gcc/tree-eh.c index 10ef2e3157c..4246dca8806 100644 --- a/gcc/tree-eh.c +++ b/gcc/tree-eh.c @@ -2936,6 +2936,16 @@ stmt_could_throw_p (function *fun, gimple *stmt) } } +/* Return true if STMT in function FUN must be assumed necessary because of + non-call exceptions. */ + +bool +stmt_unremovable_because_of_non_call_eh_p (function *fun, gimple *stmt) +{ + return (fun->can_throw_non_call_exceptions + && !fun->can_delete_dead_exceptions + && stmt_could_throw_p (fun, stmt)); +} /* Return true if expression T could throw an exception. */ diff --git a/gcc/tree-eh.h b/gcc/tree-eh.h index cb1019e0d87..ba911cadbe7 100644 --- a/gcc/tree-eh.h +++ b/gcc/tree-eh.h @@ -39,6 +39,7 @@ extern bool operation_could_trap_p (enum tree_code, bool, bool, tree); extern bool tree_could_trap_p (tree); extern tree rewrite_to_non_trapping_overflow (tree); extern bool stmt_could_throw_p (function *, gimple *); +extern bool stmt_unremovable_because_of_non_call_eh_p (function *, gimple *); extern bool tree_could_throw_p (tree); extern bool stmt_can_throw_external (function *, gimple *); extern bool stmt_can_throw_internal (function *, gimple *); diff --git a/gcc/tree-ssa-dce.c b/gcc/tree-ssa-dce.c index 757cfad5b5e..fae5ae72340 100644 --- a/gcc/tree-ssa-dce.c +++ b/gcc/tree-ssa-dce.c @@ -201,9 +201,7 @@ mark_stmt_if_obviously_necessary (gimple *stmt, bool aggressive) { /* With non-call exceptions, we have to assume that all statements could throw. If a statement could throw, it can be deemed necessary. */ - if (cfun->can_throw_non_call_exceptions - && !cfun->can_delete_dead_exceptions - && stmt_could_throw_p (cfun, stmt)) + if (stmt_unremovable_because_of_non_call_eh_p (cfun, stmt)) { mark_stmt_necessary (stmt, true); return;