From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 1075) id E86413858C60; Tue, 2 Nov 2021 17:44:29 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org E86413858C60 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="utf-8" From: Jan Hubicka To: gcc-cvs@gcc.gnu.org Subject: [gcc r12-4849] addS EAF_NOT_RETURNED_DIRECTLY X-Act-Checkin: gcc X-Git-Author: Jan Hubicka X-Git-Refname: refs/heads/master X-Git-Oldrev: c33a5cc9e7f1475108892abb147f9382ecbaec12 X-Git-Newrev: f19791565d7ed31c2a895fc29b772c2c7ed390e8 Message-Id: <20211102174429.E86413858C60@sourceware.org> Date: Tue, 2 Nov 2021 17:44:29 +0000 (GMT) X-BeenThere: gcc-cvs@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-cvs mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 02 Nov 2021 17:44:30 -0000 https://gcc.gnu.org/g:f19791565d7ed31c2a895fc29b772c2c7ed390e8 commit r12-4849-gf19791565d7ed31c2a895fc29b772c2c7ed390e8 Author: Jan Hubicka Date: Tue Nov 2 18:43:17 2021 +0100 addS EAF_NOT_RETURNED_DIRECTLY addS EAF_NOT_RETURNED_DIRECTLY which works similarly as EAF_NODIRECTESCAPE. Values pointed to by a given argument may be returned but not the argument itself. This helps PTA quite noticeably because we mostly care about tracking points to which given memory location can escape. gcc/ChangeLog: * tree-core.h (EAF_NOT_RETURNED_DIRECTLY): New flag. (EAF_NOREAD): Renumber. * ipa-modref.c (dump_eaf_flags): Dump EAF_NOT_RETURNED_DIRECTLY. (remove_useless_eaf_flags): Handle EAF_NOT_RETURNED_DIRECTLY (deref_flags): Likewise. (modref_lattice::init): Likewise. (modref_lattice::merge): Likewise. (merge_call_lhs_flags): Likewise. (analyze_ssa_name_flags): Likewise. (modref_merge_call_site_flags): Likewise. * tree-ssa-structalias.c (handle_call_arg): Likewise. gcc/testsuite/ChangeLog: * g++.dg/ipa/modref-1.C: Update template. * gcc.dg/tree-ssa/modref-10.c: New test. Diff: --- gcc/ipa-modref.c | 39 ++++++++++++++++++++++--------- gcc/testsuite/g++.dg/ipa/modref-1.C | 2 +- gcc/testsuite/gcc.dg/tree-ssa/modref-10.c | 20 ++++++++++++++++ gcc/tree-core.h | 6 ++++- gcc/tree-ssa-structalias.c | 12 ++++++++-- 5 files changed, 64 insertions(+), 15 deletions(-) diff --git a/gcc/ipa-modref.c b/gcc/ipa-modref.c index d866d9ed6b3..c0aae084dbd 100644 --- a/gcc/ipa-modref.c +++ b/gcc/ipa-modref.c @@ -160,6 +160,8 @@ dump_eaf_flags (FILE *out, int flags, bool newline = true) fprintf (out, " unused"); if (flags & EAF_NOT_RETURNED) fprintf (out, " not_returned"); + if (flags & EAF_NOT_RETURNED_DIRECTLY) + fprintf (out, " not_returned_directly"); if (flags & EAF_NOREAD) fprintf (out, " noread"); if (newline) @@ -295,7 +297,7 @@ remove_useless_eaf_flags (int eaf_flags, int ecf_flags, bool returns_void) else if (ecf_flags & ECF_PURE) eaf_flags &= ~implicit_pure_eaf_flags; else if ((ecf_flags & ECF_NORETURN) || returns_void) - eaf_flags &= ~EAF_NOT_RETURNED; + eaf_flags &= ~(EAF_NOT_RETURNED | EAF_NOT_RETURNED_DIRECTLY); return eaf_flags; } @@ -1373,7 +1375,7 @@ memory_access_to (tree op, tree ssa_name) static int deref_flags (int flags, bool ignore_stores) { - int ret = EAF_NODIRECTESCAPE; + int ret = EAF_NODIRECTESCAPE | EAF_NOT_RETURNED_DIRECTLY; /* If argument is unused just account for the read involved in dereference. */ if (flags & EAF_UNUSED) @@ -1458,7 +1460,8 @@ modref_lattice::init () { /* All flags we track. */ int f = EAF_DIRECT | EAF_NOCLOBBER | EAF_NOESCAPE | EAF_UNUSED - | EAF_NODIRECTESCAPE | EAF_NOT_RETURNED | EAF_NOREAD; + | EAF_NODIRECTESCAPE | EAF_NOT_RETURNED | + EAF_NOT_RETURNED_DIRECTLY | EAF_NOREAD; flags = f; /* Check that eaf_flags_t is wide enough to hold all flags. */ gcc_checking_assert (f == flags); @@ -1540,6 +1543,8 @@ modref_lattice::merge (int f) Fnspec machinery does set both so compensate for this. */ if (f & EAF_NOESCAPE) f |= EAF_NODIRECTESCAPE; + if (f & EAF_NOT_RETURNED) + f |= EAF_NOT_RETURNED_DIRECTLY; if ((flags & f) != flags) { flags &= f; @@ -1647,7 +1652,9 @@ merge_call_lhs_flags (gcall *call, int arg, int index, bool deref, && (flags & ERF_RETURN_ARG_MASK) != arg) return; - if (gimple_call_arg_flags (call, arg) & (EAF_NOT_RETURNED | EAF_UNUSED)) + int eaf_flags = gimple_call_arg_flags (call, arg); + + if (eaf_flags & (EAF_NOT_RETURNED | EAF_UNUSED)) return; /* If return value is SSA name determine its flags. */ @@ -1655,12 +1662,14 @@ merge_call_lhs_flags (gcall *call, int arg, int index, bool deref, { tree lhs = gimple_call_lhs (call); analyze_ssa_name_flags (lhs, lattice, depth + 1, ipa); - if (deref) + if (deref || (eaf_flags & EAF_NOT_RETURNED_DIRECTLY)) lattice[index].merge_deref (lattice[SSA_NAME_VERSION (lhs)], false); else lattice[index].merge (lattice[SSA_NAME_VERSION (lhs)]); } /* In the case of memory store we can do nothing. */ + else if (eaf_flags & EAF_NOT_RETURNED_DIRECTLY) + lattice[index].merge (deref_flags (0, false)); else lattice[index].merge (0); } @@ -1731,11 +1740,13 @@ analyze_ssa_name_flags (tree name, vec &lattice, int depth, && DECL_BY_REFERENCE (DECL_RESULT (current_function_decl))) ; else if (gimple_return_retval (ret) == name) - lattice[index].merge (~(EAF_UNUSED | EAF_NOT_RETURNED)); + lattice[index].merge (~(EAF_UNUSED | EAF_NOT_RETURNED + | EAF_NOT_RETURNED_DIRECTLY)); else if (memory_access_to (gimple_return_retval (ret), name)) { lattice[index].merge_direct_load (); - lattice[index].merge (~(EAF_UNUSED | EAF_NOT_RETURNED)); + lattice[index].merge (~(EAF_UNUSED | EAF_NOT_RETURNED + | EAF_NOT_RETURNED_DIRECTLY)); } } /* Account for LHS store, arg loads and flags from callee function. */ @@ -1794,7 +1805,8 @@ analyze_ssa_name_flags (tree name, vec &lattice, int depth, if (!(ecf_flags & (ECF_CONST | ECF_NOVOPS))) { int call_flags = gimple_call_arg_flags (call, i) - | EAF_NOT_RETURNED; + | EAF_NOT_RETURNED + | EAF_NOT_RETURNED_DIRECTLY; if (ignore_stores) call_flags |= ignore_stores_eaf_flags; @@ -1817,7 +1829,8 @@ analyze_ssa_name_flags (tree name, vec &lattice, int depth, { int call_flags = deref_flags (gimple_call_arg_flags (call, i) - | EAF_NOT_RETURNED, ignore_stores); + | EAF_NOT_RETURNED + | EAF_NOT_RETURNED_DIRECTLY, ignore_stores); if (!record_ipa) lattice[index].merge (call_flags); else @@ -3858,14 +3871,18 @@ modref_merge_call_site_flags (escape_summary *sum, flags_lto |= ignore_stores_eaf_flags; } /* Returning the value is already accounted to at local propagation. */ - flags |= ee->min_flags | EAF_NOT_RETURNED; - flags_lto |= ee->min_flags | EAF_NOT_RETURNED; + flags |= ee->min_flags | EAF_NOT_RETURNED | EAF_NOT_RETURNED_DIRECTLY; + flags_lto |= ee->min_flags | EAF_NOT_RETURNED | EAF_NOT_RETURNED_DIRECTLY; /* Noescape implies that value also does not escape directly. Fnspec machinery does set both so compensate for this. */ if (flags & EAF_NOESCAPE) flags |= EAF_NODIRECTESCAPE; if (flags_lto & EAF_NOESCAPE) flags_lto |= EAF_NODIRECTESCAPE; + if (flags & EAF_NOT_RETURNED) + flags |= EAF_NOT_RETURNED_DIRECTLY; + if (flags_lto & EAF_NOT_RETURNED) + flags_lto |= EAF_NOT_RETURNED_DIRECTLY; if (!(flags & EAF_UNUSED) && cur_summary && ee->parm_index < (int)cur_summary->arg_flags.length ()) { diff --git a/gcc/testsuite/g++.dg/ipa/modref-1.C b/gcc/testsuite/g++.dg/ipa/modref-1.C index 0acae2114dd..eaa14ea5c7f 100644 --- a/gcc/testsuite/g++.dg/ipa/modref-1.C +++ b/gcc/testsuite/g++.dg/ipa/modref-1.C @@ -31,5 +31,5 @@ int main() return 0; } /* { dg-final { scan-tree-dump "Function found to be const: {anonymous}::B::genB" "local-pure-const1" } } */ -/* { dg-final { scan-tree-dump "Retslot flags: direct noescape nodirectescape not_returned noread" "modref1" } } */ +/* { dg-final { scan-tree-dump "Retslot flags: direct noescape nodirectescape not_returned not_returned_directly noread" "modref1" } } */ diff --git a/gcc/testsuite/gcc.dg/tree-ssa/modref-10.c b/gcc/testsuite/gcc.dg/tree-ssa/modref-10.c new file mode 100644 index 00000000000..c608408809d --- /dev/null +++ b/gcc/testsuite/gcc.dg/tree-ssa/modref-10.c @@ -0,0 +1,20 @@ +/* { dg-do link } */ +/* { dg-options "-O2 -fdump-tree-modref1" } */ +void linker_error (); +__attribute__((noinline)) +int * +test (int **a) +{ + return *a; +} +int +main() +{ + int val; + int *a=&val; + int *b = test (&a); + if (b == (int *)&a) + linker_error (); + return 0; +} +/* { dg-final { scan-tree-dump "parm 0 flags: noclobber noescape nodirectescape not_returned_directly" "modref1"} } */ diff --git a/gcc/tree-core.h b/gcc/tree-core.h index d3d2a8d812f..f0c65a25f07 100644 --- a/gcc/tree-core.h +++ b/gcc/tree-core.h @@ -117,8 +117,12 @@ struct die_struct; /* Nonzero if the argument does not escape to return value. */ #define EAF_NOT_RETURNED (1 << 5) +/* Nonzero if the argument itself does not escape + to return value but memory referenced by it may escape. */ +#define EAF_NOT_RETURNED_DIRECTLY (1 << 6) + /* Nonzero if the argument is not read. */ -#define EAF_NOREAD (1 << 6) +#define EAF_NOREAD (1 << 7) /* Call return flags. */ /* Mask for the argument number that is returned. Lower two bits of diff --git a/gcc/tree-ssa-structalias.c b/gcc/tree-ssa-structalias.c index 99072df0768..5f24c0171f0 100644 --- a/gcc/tree-ssa-structalias.c +++ b/gcc/tree-ssa-structalias.c @@ -4082,8 +4082,16 @@ handle_call_arg (gcall *stmt, tree arg, vec *results, int flags, { struct constraint_expr cexpr; cexpr.var = tem->id; - cexpr.type = SCALAR; - cexpr.offset = 0; + if (flags & EAF_NOT_RETURNED_DIRECTLY) + { + cexpr.type = DEREF; + cexpr.offset = UNKNOWN_OFFSET; + } + else + { + cexpr.type = SCALAR; + cexpr.offset = 0; + } results->safe_push (cexpr); }