From d70ef65692fced7ab72e0aceeff7407e5a34d96d Mon Sep 17 00:00:00 2001 From: Jan Hubicka Date: Wed, 10 Nov 2021 13:08:41 +0100 Subject: [PATCH] Make EAF flags more regular (and expressive) I hoped that I am done with EAF flags related changes, but while looking into the Fortran testcases I noticed that I have designed them in unnecesarily restricted way. I followed the scheme of NOESCAPE and NODIRECTESCAPE which is however the only property tht is naturally transitive. This patch replaces the existing flags by 9 flags: EAF_UNUSED EAF_NO_DIRECT_CLOBBER and EAF_NO_INDIRECT_CLOBBER EAF_NO_DIRECT_READ and EAF_NO_INDIRECT_READ EAF_NO_DIRECT_ESCAPE and EAF_NO_INDIRECT_ESCAPE EAF_NO_DIRECT_READ and EAF_NO_INDIRECT_READ So I have removed the unified EAF_DIRECT flag and made each of the flags to come in direct and indirect variant. Newly the indirect variant is not implied by direct (well except for escape but it is not special cased in the code) Consequently we can analyse i.e. the case where function reads directly and clobber indirectly as in the following testcase: struct wrap { void **array; }; __attribute__ ((noinline)) void write_array (struct wrap *ptr) { ptr->array[0]=0; } int test () { void *arrayval; struct wrap w = {&arrayval}; write_array (&w); return w.array == &arrayval; } This is pretty common in array descriptors and also C++ pointer wrappers or structures containing pointers to arrays. Other advantage is that !binds_to_current_def_p functions we can still track the fact that the value is not clobbered indirectly while previously we implied EAF_DIRECT for all three cases. Finally the propagation becomes more regular and I hope easier to understand because the flags are handled in a symmetric way. In tree-ssa-structalias I now produce "callarg" var_info as before and if necessary also "indircallarg" for the indirect accesses. I added some logic to optimize the common case where we can not make difference between direct and indirect. gcc/ChangeLog: 2021-11-09 Jan Hubicka * tree-core.h (EAF_DIRECT): Remove. (EAF_NOCLOBBER): Remove. (EAF_UNUSED): Remove. (EAF_NOESCAPE): Remove. (EAF_NO_DIRECT_CLOBBER): New. (EAF_NO_INDIRECT_CLOBBER): New. (EAF_NODIRECTESCAPE): Remove. (EAF_NO_DIRECT_ESCAPE): New. (EAF_NO_INDIRECT_ESCAPE): New. (EAF_NOT_RETURNED): Remove. (EAF_NOT_RETURNED_INDIRECTLY): New. (EAF_NOREAD): Remove. (EAF_NO_DIRECT_READ): New. (EAF_NO_INDIRECT_READ): New. * gimple.c (gimple_call_arg_flags): Update for new flags. (gimple_call_retslot_flags): Update for new flags. * ipa-modref.c (dump_eaf_flags): Likewise. (remove_useless_eaf_flags): Likewise. (deref_flags): Likewise. (modref_lattice::init): Likewise. (modref_lattice::merge): Likewise. (modref_lattice::merge_direct_load): Likewise. (modref_lattice::merge_direct_store): Likewise. (modref_eaf_analysis::merge_call_lhs_flags): Likewise. (callee_to_caller_flags): Likewise. (modref_eaf_analysis::analyze_ssa_name): Likewise. (modref_eaf_analysis::propagate): Likewise. (modref_merge_call_site_flags): Likewise. * ipa-modref.h (interposable_eaf_flags): Likewise. * tree-ssa-alias.c: (ref_maybe_used_by_call_p_1) Likewise. * tree-ssa-structalias.c (handle_call_arg): Likewise. (handle_rhs_call): Likewise. * tree-ssa-uninit.c (maybe_warn_pass_by_reference): Likewise. gcc/testsuite/ChangeLog: * g++.dg/ipa/modref-1.C: Update template. * gcc.dg/ipa/modref-3.c: Update template. * gcc.dg/lto/modref-3_0.c: Update template. * gcc.dg/lto/modref-4_0.c: Update template. * gcc.dg/tree-ssa/modref-10.c: Update template. * gcc.dg/tree-ssa/modref-11.c: Update template. * gcc.dg/tree-ssa/modref-5.c: Update template. * gcc.dg/tree-ssa/modref-6.c: Update template. * gcc.dg/tree-ssa/modref-13.c: New test. --- gcc/gimple.c | 9 +- gcc/ipa-modref.c | 204 ++++++++++++---------- gcc/ipa-modref.h | 42 +++-- gcc/testsuite/g++.dg/ipa/modref-1.C | 2 +- gcc/testsuite/gcc.dg/ipa/modref-3.c | 2 +- gcc/testsuite/gcc.dg/lto/modref-3_0.c | 2 +- gcc/testsuite/gcc.dg/lto/modref-4_0.c | 2 +- gcc/testsuite/gcc.dg/tree-ssa/modref-10.c | 2 +- gcc/testsuite/gcc.dg/tree-ssa/modref-11.c | 2 +- gcc/testsuite/gcc.dg/tree-ssa/modref-13.c | 21 +++ gcc/testsuite/gcc.dg/tree-ssa/modref-5.c | 2 +- gcc/testsuite/gcc.dg/tree-ssa/modref-6.c | 6 +- gcc/tree-core.h | 33 ++-- gcc/tree-ssa-alias.c | 2 +- gcc/tree-ssa-structalias.c | 154 ++++++++++++---- gcc/tree-ssa-uninit.c | 3 +- 16 files changed, 309 insertions(+), 179 deletions(-) create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/modref-13.c diff --git a/gcc/gimple.c b/gcc/gimple.c index 9e65fa61c73..1e0fad92e15 100644 --- a/gcc/gimple.c +++ b/gcc/gimple.c @@ -1575,11 +1575,12 @@ gimple_call_arg_flags (const gcall *stmt, unsigned arg) else { if (fnspec.arg_direct_p (arg)) - flags |= EAF_DIRECT; + flags |= EAF_NO_INDIRECT_READ | EAF_NO_INDIRECT_ESCAPE + | EAF_NOT_RETURNED_INDIRECTLY | EAF_NO_INDIRECT_CLOBBER; if (fnspec.arg_noescape_p (arg)) - flags |= EAF_NOESCAPE | EAF_NODIRECTESCAPE; + flags |= EAF_NO_DIRECT_ESCAPE | EAF_NO_INDIRECT_ESCAPE; if (fnspec.arg_readonly_p (arg)) - flags |= EAF_NOCLOBBER; + flags |= EAF_NO_DIRECT_CLOBBER | EAF_NO_INDIRECT_CLOBBER; } } tree callee = gimple_call_fndecl (stmt); @@ -1608,7 +1609,7 @@ gimple_call_arg_flags (const gcall *stmt, unsigned arg) int gimple_call_retslot_flags (const gcall *stmt) { - int flags = EAF_DIRECT | EAF_NOREAD; + int flags = implicit_retslot_eaf_flags; tree callee = gimple_call_fndecl (stmt); if (callee) diff --git a/gcc/ipa-modref.c b/gcc/ipa-modref.c index e3cad3ee447..14c3894d7ba 100644 --- a/gcc/ipa-modref.c +++ b/gcc/ipa-modref.c @@ -148,22 +148,24 @@ struct escape_entry static void dump_eaf_flags (FILE *out, int flags, bool newline = true) { - if (flags & EAF_DIRECT) - fprintf (out, " direct"); - if (flags & EAF_NOCLOBBER) - fprintf (out, " noclobber"); - if (flags & EAF_NOESCAPE) - fprintf (out, " noescape"); - if (flags & EAF_NODIRECTESCAPE) - fprintf (out, " nodirectescape"); if (flags & EAF_UNUSED) fprintf (out, " unused"); - if (flags & EAF_NOT_RETURNED) - fprintf (out, " not_returned"); + if (flags & EAF_NO_DIRECT_CLOBBER) + fprintf (out, " no_direct_clobber"); + if (flags & EAF_NO_INDIRECT_CLOBBER) + fprintf (out, " no_indirect_clobber"); + if (flags & EAF_NO_DIRECT_ESCAPE) + fprintf (out, " no_direct_escape"); + if (flags & EAF_NO_INDIRECT_ESCAPE) + fprintf (out, " no_indirect_escape"); if (flags & EAF_NOT_RETURNED_DIRECTLY) fprintf (out, " not_returned_directly"); - if (flags & EAF_NOREAD) - fprintf (out, " noread"); + if (flags & EAF_NOT_RETURNED_INDIRECTLY) + fprintf (out, " not_returned_indirectly"); + if (flags & EAF_NO_DIRECT_READ) + fprintf (out, " no_direct_read"); + if (flags & EAF_NO_INDIRECT_READ) + fprintf (out, " no_indirect_read"); if (newline) fprintf (out, "\n"); } @@ -296,7 +298,7 @@ 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_NOT_RETURNED_DIRECTLY); + eaf_flags &= ~(EAF_NOT_RETURNED_DIRECTLY | EAF_NOT_RETURNED_INDIRECTLY); return eaf_flags; } @@ -1412,35 +1414,32 @@ memory_access_to (tree op, tree ssa_name) static int deref_flags (int flags, bool ignore_stores) { - int ret = EAF_NODIRECTESCAPE | EAF_NOT_RETURNED_DIRECTLY; + /* Dereference is also a direct read but dereferenced value does not + yield any other direct use. */ + int ret = EAF_NO_DIRECT_CLOBBER | EAF_NO_DIRECT_ESCAPE + | EAF_NOT_RETURNED_DIRECTLY; /* If argument is unused just account for the read involved in dereference. */ if (flags & EAF_UNUSED) - ret |= EAF_DIRECT | EAF_NOCLOBBER | EAF_NOESCAPE | EAF_NOT_RETURNED; + ret |= EAF_NO_INDIRECT_READ | EAF_NO_INDIRECT_CLOBBER + | EAF_NO_INDIRECT_ESCAPE; else { - if ((flags & EAF_NOCLOBBER) || ignore_stores) - ret |= EAF_NOCLOBBER; - if ((flags & EAF_NOESCAPE) || ignore_stores) - ret |= EAF_NOESCAPE; - /* If the value dereferenced is not used for another load or store - we can still consider ARG as used only directly. - - Consider - - int - test (int *a) - { - return *a!=0; - } - - */ - if ((flags & (EAF_NOREAD | EAF_NOT_RETURNED | EAF_NOESCAPE | EAF_DIRECT)) - == (EAF_NOREAD | EAF_NOT_RETURNED | EAF_NOESCAPE | EAF_DIRECT) - && ((flags & EAF_NOCLOBBER) || ignore_stores)) - ret |= EAF_DIRECT; - if (flags & EAF_NOT_RETURNED) - ret |= EAF_NOT_RETURNED; + /* Direct or indirect accesses leads to indirect accesses. */ + if (((flags & EAF_NO_DIRECT_CLOBBER) + && (flags & EAF_NO_INDIRECT_CLOBBER)) + || ignore_stores) + ret |= EAF_NO_INDIRECT_CLOBBER; + if (((flags & EAF_NO_DIRECT_ESCAPE) + && (flags & EAF_NO_INDIRECT_ESCAPE)) + || ignore_stores) + ret |= EAF_NO_INDIRECT_ESCAPE; + if ((flags & EAF_NO_DIRECT_READ) + && (flags & EAF_NO_INDIRECT_READ)) + ret |= EAF_NO_INDIRECT_READ; + if ((flags & EAF_NOT_RETURNED_DIRECTLY) + && (flags & EAF_NOT_RETURNED_INDIRECTLY)) + ret |= EAF_NOT_RETURNED_INDIRECTLY; } return ret; } @@ -1508,9 +1507,11 @@ void modref_lattice::init () { /* All flags we track. */ - int f = EAF_DIRECT | EAF_NOCLOBBER | EAF_NOESCAPE | EAF_UNUSED - | EAF_NODIRECTESCAPE | EAF_NOT_RETURNED | - EAF_NOT_RETURNED_DIRECTLY | EAF_NOREAD; + int f = EAF_NO_DIRECT_CLOBBER | EAF_NO_INDIRECT_CLOBBER + | EAF_NO_DIRECT_ESCAPE | EAF_NO_INDIRECT_ESCAPE + | EAF_NO_DIRECT_READ | EAF_NO_INDIRECT_READ + | EAF_NOT_RETURNED_DIRECTLY | EAF_NOT_RETURNED_INDIRECTLY + | EAF_UNUSED; flags = f; /* Check that eaf_flags_t is wide enough to hold all flags. */ gcc_checking_assert (f == flags); @@ -1589,12 +1590,6 @@ modref_lattice::merge (int f) { if (f & EAF_UNUSED) return false; - /* Noescape implies that value also does not escape directly. - 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; @@ -1664,7 +1659,7 @@ modref_lattice::merge_deref (const modref_lattice &with, bool ignore_stores) bool modref_lattice::merge_direct_load () { - return merge (~(EAF_UNUSED | EAF_NOREAD)); + return merge (~(EAF_UNUSED | EAF_NO_DIRECT_READ)); } /* Merge in flags for direct store. */ @@ -1672,7 +1667,7 @@ modref_lattice::merge_direct_load () bool modref_lattice::merge_direct_store () { - return merge (~(EAF_UNUSED | EAF_NOCLOBBER)); + return merge (~(EAF_UNUSED | EAF_NO_DIRECT_CLOBBER)); } /* Analyzer of EAF flags. @@ -1729,22 +1724,30 @@ private: auto_vec m_names_to_propagate; void merge_with_ssa_name (tree dest, tree src, bool deref); - void merge_call_lhs_flags (gcall *call, int arg, tree name, bool deref); + void merge_call_lhs_flags (gcall *call, int arg, tree name, bool direct, + bool deref); }; -/* Call statements may return their parameters. Consider argument number +/* Call statements may return tgeir parameters. Consider argument number ARG of USE_STMT and determine flags that can needs to be cleared in case pointer possibly indirectly references from ARG I is returned. + If DIRECT is true consider direct returns and if INDIRECT consider + indirect returns. LATTICE, DEPTH and ipa are same as in analyze_ssa_name. ARG is set to -1 for static chain. */ void modref_eaf_analysis::merge_call_lhs_flags (gcall *call, int arg, - tree name, bool deref) + tree name, bool direct, + bool indirect) { int index = SSA_NAME_VERSION (name); + /* If value is not returned at all, do nothing. */ + if (!direct && !indirect) + return; + /* If there is no return value, no flags are affected. */ if (!gimple_call_lhs (call)) return; @@ -1763,10 +1766,13 @@ modref_eaf_analysis::merge_call_lhs_flags (gcall *call, int arg, if (TREE_CODE (gimple_call_lhs (call)) == SSA_NAME) { tree lhs = gimple_call_lhs (call); - merge_with_ssa_name (name, lhs, deref); + if (direct) + merge_with_ssa_name (name, lhs, false); + if (indirect) + merge_with_ssa_name (name, lhs, true); } /* In the case of memory store we can do nothing. */ - else if (deref) + else if (!direct) m_lattice[index].merge (deref_flags (0, false)); else m_lattice[index].merge (0); @@ -1782,18 +1788,19 @@ callee_to_caller_flags (int call_flags, bool ignore_stores, { /* call_flags is about callee returning a value that is not the same as caller returning it. */ - call_flags |= EAF_NOT_RETURNED - | EAF_NOT_RETURNED_DIRECTLY; + call_flags |= EAF_NOT_RETURNED_DIRECTLY + | EAF_NOT_RETURNED_INDIRECTLY; /* TODO: We miss return value propagation. Be conservative and if value escapes to memory also mark it as escaping. */ if (!ignore_stores && !(call_flags & EAF_UNUSED)) { - if (!(call_flags & EAF_NOESCAPE)) - lattice.merge (~(EAF_NOT_RETURNED | EAF_UNUSED)); - if (!(call_flags & (EAF_NODIRECTESCAPE | EAF_NOESCAPE))) + if (!(call_flags & EAF_NO_DIRECT_ESCAPE)) lattice.merge (~(EAF_NOT_RETURNED_DIRECTLY - | EAF_NOT_RETURNED + | EAF_NOT_RETURNED_INDIRECTLY + | EAF_UNUSED)); + if (!(call_flags & EAF_NO_INDIRECT_ESCAPE)) + lattice.merge (~(EAF_NOT_RETURNED_INDIRECTLY | EAF_UNUSED)); } else @@ -1869,13 +1876,13 @@ modref_eaf_analysis::analyze_ssa_name (tree name) && DECL_BY_REFERENCE (DECL_RESULT (current_function_decl))) ; else if (gimple_return_retval (ret) == name) - m_lattice[index].merge (~(EAF_UNUSED | EAF_NOT_RETURNED + m_lattice[index].merge (~(EAF_UNUSED | EAF_NOT_RETURNED_DIRECTLY | EAF_NOT_RETURNED_DIRECTLY)); else if (memory_access_to (gimple_return_retval (ret), name)) { m_lattice[index].merge_direct_load (); - m_lattice[index].merge (~(EAF_UNUSED | EAF_NOT_RETURNED - | EAF_NOT_RETURNED_DIRECTLY)); + m_lattice[index].merge (~(EAF_UNUSED + | EAF_NOT_RETURNED_INDIRECTLY)); } } /* Account for LHS store, arg loads and flags from callee function. */ @@ -1889,7 +1896,7 @@ modref_eaf_analysis::analyze_ssa_name (tree name) is on since that would allow propagation of this from -fno-ipa-pta to -fipa-pta functions. */ if (gimple_call_fn (use_stmt) == name) - m_lattice[index].merge (~(EAF_NOCLOBBER | EAF_UNUSED)); + m_lattice[index].merge (~(EAF_NO_DIRECT_CLOBBER | EAF_UNUSED)); /* Recursion would require bit of propagation; give up for now. */ if (callee && !m_ipa && recursive_call_p (current_function_decl, @@ -1932,14 +1939,14 @@ modref_eaf_analysis::analyze_ssa_name (tree name) arg is written to itself which is an escape. */ if (!isretslot) { - if (!(call_flags & (EAF_NOT_RETURNED | EAF_UNUSED))) - m_lattice[index].merge (~(EAF_NOESCAPE - | EAF_UNUSED)); if (!(call_flags & (EAF_NOT_RETURNED_DIRECTLY - | EAF_UNUSED - | EAF_NOT_RETURNED))) - m_lattice[index].merge (~(EAF_NODIRECTESCAPE - | EAF_NOESCAPE + | EAF_UNUSED))) + m_lattice[index].merge (~(EAF_NO_DIRECT_ESCAPE + | EAF_NO_INDIRECT_ESCAPE + | EAF_UNUSED)); + if (!(call_flags & (EAF_NOT_RETURNED_INDIRECTLY + | EAF_UNUSED))) + m_lattice[index].merge (~(EAF_NO_INDIRECT_ESCAPE | EAF_UNUSED)); call_flags = callee_to_caller_flags (call_flags, false, @@ -1953,9 +1960,11 @@ modref_eaf_analysis::analyze_ssa_name (tree name) && (gimple_call_chain (call) == name)) { int call_flags = gimple_call_static_chain_flags (call); - if (!ignore_retval - && !(call_flags & (EAF_NOT_RETURNED | EAF_UNUSED))) - merge_call_lhs_flags (call, -1, name, false); + if (!ignore_retval && !(call_flags & EAF_UNUSED)) + merge_call_lhs_flags + (call, -1, name, + !(call_flags & EAF_NOT_RETURNED_DIRECTLY), + !(call_flags & EAF_NOT_RETURNED_INDIRECTLY)); call_flags = callee_to_caller_flags (call_flags, ignore_stores, m_lattice[index]); @@ -1974,11 +1983,11 @@ modref_eaf_analysis::analyze_ssa_name (tree name) if (gimple_call_arg (call, i) == name) { int call_flags = gimple_call_arg_flags (call, i); - if (!ignore_retval && !(call_flags - & (EAF_NOT_RETURNED | EAF_UNUSED))) + if (!ignore_retval && !(call_flags & EAF_UNUSED)) merge_call_lhs_flags (call, i, name, - call_flags & EAF_NOT_RETURNED_DIRECTLY); + !(call_flags & EAF_NOT_RETURNED_DIRECTLY), + !(call_flags & EAF_NOT_RETURNED_INDIRECTLY)); if (!(ecf_flags & (ECF_CONST | ECF_NOVOPS))) { call_flags = callee_to_caller_flags @@ -1996,9 +2005,10 @@ modref_eaf_analysis::analyze_ssa_name (tree name) { int call_flags = deref_flags (gimple_call_arg_flags (call, i), ignore_stores); - if (!ignore_retval - && !(call_flags & (EAF_NOT_RETURNED | EAF_UNUSED))) - merge_call_lhs_flags (call, i, name, true); + if (!ignore_retval && !(call_flags & EAF_UNUSED) + && !(call_flags & EAF_NOT_RETURNED_DIRECTLY) + && !(call_flags & EAF_NOT_RETURNED_INDIRECTLY)) + merge_call_lhs_flags (call, i, name, false, true); if (ecf_flags & (ECF_CONST | ECF_NOVOPS)) m_lattice[index].merge_direct_load (); else @@ -2281,8 +2291,7 @@ modref_eaf_analysis::propagate () fprintf (dump_file, " New lattice: "); m_lattice[target].dump (dump_file); } - if (target <= (int)i) - changed = true; + changed = true; m_lattice[target].changed = true; } } @@ -2820,6 +2829,14 @@ modref_generate (void) } /* ANON namespace. */ +/* Debugging helper. */ + +void +debug_eaf_flags (int flags) +{ + dump_eaf_flags (stderr, flags, true); +} + /* Called when a new function is inserted to callgraph late. */ void @@ -4232,7 +4249,8 @@ modref_merge_call_site_flags (escape_summary *sum, int flags = 0; int flags_lto = 0; /* Returning the value is already accounted to at local propagation. */ - int implicit_flags = EAF_NOT_RETURNED | EAF_NOT_RETURNED_DIRECTLY; + int implicit_flags = EAF_NOT_RETURNED_DIRECTLY + | EAF_NOT_RETURNED_INDIRECTLY; if (summary && ee->arg < summary->arg_flags.length ()) flags = summary->arg_flags[ee->arg]; @@ -4263,11 +4281,15 @@ modref_merge_call_site_flags (escape_summary *sum, else { if (fnspec.arg_direct_p (ee->arg)) - fnspec_flags |= EAF_DIRECT; + fnspec_flags |= EAF_NO_INDIRECT_READ + | EAF_NO_INDIRECT_ESCAPE + | EAF_NOT_RETURNED_INDIRECTLY + | EAF_NO_INDIRECT_CLOBBER; if (fnspec.arg_noescape_p (ee->arg)) - fnspec_flags |= EAF_NOESCAPE | EAF_NODIRECTESCAPE; + fnspec_flags |= EAF_NO_DIRECT_ESCAPE + | EAF_NO_INDIRECT_ESCAPE; if (fnspec.arg_readonly_p (ee->arg)) - fnspec_flags |= EAF_NOCLOBBER; + flags |= EAF_NO_DIRECT_CLOBBER | EAF_NO_INDIRECT_CLOBBER; } } implicit_flags |= fnspec_flags; @@ -4281,16 +4303,6 @@ modref_merge_call_site_flags (escape_summary *sum, flags = interposable_eaf_flags (flags, implicit_flags); flags_lto = interposable_eaf_flags (flags_lto, implicit_flags); } - /* 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 ()) { @@ -4695,8 +4707,6 @@ ipa_modref_c_finalize () if (optimization_summaries) ggc_delete (optimization_summaries); optimization_summaries = NULL; - gcc_checking_assert (!summaries - || flag_incremental_link == INCREMENTAL_LINK_LTO); if (summaries_lto) ggc_delete (summaries_lto); summaries_lto = NULL; diff --git a/gcc/ipa-modref.h b/gcc/ipa-modref.h index 20170a65ded..482c4e4633e 100644 --- a/gcc/ipa-modref.h +++ b/gcc/ipa-modref.h @@ -21,7 +21,7 @@ along with GCC; see the file COPYING3. If not see #define IPA_MODREF_H typedef modref_tree modref_records; -typedef unsigned char eaf_flags_t; +typedef unsigned short eaf_flags_t; /* Single function summary. */ @@ -48,15 +48,28 @@ void ipa_modref_c_finalize (); void ipa_merge_modref_summary_after_inlining (cgraph_edge *e); /* All flags that are implied by the ECF_CONST functions. */ -static const int implicit_const_eaf_flags = EAF_DIRECT | EAF_NOCLOBBER | EAF_NOESCAPE - | EAF_NODIRECTESCAPE | EAF_NOREAD; +static const int implicit_const_eaf_flags + = EAF_NO_DIRECT_CLOBBER | EAF_NO_INDIRECT_CLOBBER + | EAF_NO_DIRECT_ESCAPE | EAF_NO_INDIRECT_ESCAPE + | EAF_NO_DIRECT_READ | EAF_NO_INDIRECT_READ + | EAF_NOT_RETURNED_INDIRECTLY; + /* All flags that are implied by the ECF_PURE function. */ -static const int implicit_pure_eaf_flags = EAF_NOCLOBBER | EAF_NOESCAPE - | EAF_NODIRECTESCAPE; +static const int implicit_pure_eaf_flags + = EAF_NO_DIRECT_CLOBBER | EAF_NO_INDIRECT_CLOBBER + | EAF_NO_DIRECT_ESCAPE | EAF_NO_INDIRECT_ESCAPE; + /* All flags implied when we know we can ignore stores (i.e. when handling call to noreturn). */ -static const int ignore_stores_eaf_flags = EAF_DIRECT | EAF_NOCLOBBER | EAF_NOESCAPE - | EAF_NODIRECTESCAPE; +static const int ignore_stores_eaf_flags + = EAF_NO_DIRECT_CLOBBER | EAF_NO_INDIRECT_CLOBBER + | EAF_NO_DIRECT_ESCAPE | EAF_NO_INDIRECT_ESCAPE; + +/* Return slot is write-only. */ +static const int implicit_retslot_eaf_flags + = EAF_NO_DIRECT_READ | EAF_NO_INDIRECT_READ + | EAF_NO_INDIRECT_ESCAPE | EAF_NO_INDIRECT_CLOBBER + | EAF_NOT_RETURNED_INDIRECTLY; /* If function does not bind to current def (i.e. it is inline in comdat section), the modref analysis may not match the behaviour of function @@ -74,16 +87,15 @@ interposable_eaf_flags (int modref_flags, int flags) if ((modref_flags & EAF_UNUSED) && !(flags & EAF_UNUSED)) { modref_flags &= ~EAF_UNUSED; - modref_flags |= EAF_NOESCAPE | EAF_NOT_RETURNED - | EAF_NOT_RETURNED_DIRECTLY | EAF_NOCLOBBER; + modref_flags |= EAF_NO_DIRECT_ESCAPE | EAF_NO_INDIRECT_ESCAPE + | EAF_NOT_RETURNED_DIRECTLY | EAF_NOT_RETURNED_INDIRECTLY + | EAF_NO_DIRECT_CLOBBER | EAF_NO_INDIRECT_CLOBBER; } /* We can not deterine that value is not read at all. */ - if ((modref_flags & EAF_NOREAD) && !(flags & EAF_NOREAD)) - modref_flags &= ~EAF_NOREAD; - /* Clear direct flags so we also know that value is possibly read - indirectly. */ - if ((modref_flags & EAF_DIRECT) && !(flags & EAF_DIRECT)) - modref_flags &= ~EAF_DIRECT; + if ((modref_flags & EAF_NO_DIRECT_READ) && !(flags & EAF_NO_DIRECT_READ)) + modref_flags &= ~EAF_NO_DIRECT_READ; + if ((modref_flags & EAF_NO_INDIRECT_READ) && !(flags & EAF_NO_INDIRECT_READ)) + modref_flags &= ~EAF_NO_INDIRECT_READ; return modref_flags; } diff --git a/gcc/testsuite/g++.dg/ipa/modref-1.C b/gcc/testsuite/g++.dg/ipa/modref-1.C index eaa14ea5c7f..c57aaca0230 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 not_returned_directly noread" "modref1" } } */ +/* { dg-final { scan-tree-dump "Retslot flags: no_indirect_clobber no_direct_escape no_indirect_escape not_returned_directly not_returned_indirectly no_direct_read no_indirect_read" "modref1" } } */ diff --git a/gcc/testsuite/gcc.dg/ipa/modref-3.c b/gcc/testsuite/gcc.dg/ipa/modref-3.c index 84013541ce8..9a20e018ae1 100644 --- a/gcc/testsuite/gcc.dg/ipa/modref-3.c +++ b/gcc/testsuite/gcc.dg/ipa/modref-3.c @@ -17,4 +17,4 @@ main () linker_error (); return 0; } -/* { dg-final { scan-ipa-dump "Static chain flags: noclobber noescape nodirectescape" "modref" } } */ +/* { dg-final { scan-ipa-dump "Static chain flags: no_direct_clobber no_indirect_clobber no_direct_escape no_indirect_escape not_returned_directly no_indirect_read" "modref" } } */ diff --git a/gcc/testsuite/gcc.dg/lto/modref-3_0.c b/gcc/testsuite/gcc.dg/lto/modref-3_0.c index bd8f96f6ec4..0210d115111 100644 --- a/gcc/testsuite/gcc.dg/lto/modref-3_0.c +++ b/gcc/testsuite/gcc.dg/lto/modref-3_0.c @@ -14,4 +14,4 @@ main() __builtin_abort (); return 0; } -/* { dg-final { scan-wpa-ipa-dump "parm 1 flags: nodirectescape" "modref" } } */ +/* { dg-final { scan-wpa-ipa-dump "parm 1 flags: no_direct_clobber no_direct_escape" "modref" } } */ diff --git a/gcc/testsuite/gcc.dg/lto/modref-4_0.c b/gcc/testsuite/gcc.dg/lto/modref-4_0.c index db90b4f1f3d..94375851146 100644 --- a/gcc/testsuite/gcc.dg/lto/modref-4_0.c +++ b/gcc/testsuite/gcc.dg/lto/modref-4_0.c @@ -14,4 +14,4 @@ main() __builtin_abort (); return 0; } -/* { dg-final { scan-wpa-ipa-dump "parm 1 flags: nodirectescape" "modref" } } */ +/* { dg-final { scan-wpa-ipa-dump "parm 1 flags: no_direct_clobber no_direct_escape" "modref" } } */ diff --git a/gcc/testsuite/gcc.dg/tree-ssa/modref-10.c b/gcc/testsuite/gcc.dg/tree-ssa/modref-10.c index c608408809d..4a6d9e54c23 100644 --- a/gcc/testsuite/gcc.dg/tree-ssa/modref-10.c +++ b/gcc/testsuite/gcc.dg/tree-ssa/modref-10.c @@ -17,4 +17,4 @@ main() linker_error (); return 0; } -/* { dg-final { scan-tree-dump "parm 0 flags: noclobber noescape nodirectescape not_returned_directly" "modref1"} } */ +/* { dg-final { scan-tree-dump "no_direct_clobber no_indirect_clobber no_direct_escape no_indirect_escape not_returned_directly no_indirect_read" "modref1"} } */ diff --git a/gcc/testsuite/gcc.dg/tree-ssa/modref-11.c b/gcc/testsuite/gcc.dg/tree-ssa/modref-11.c index de9ad16879f..cafb4f34894 100644 --- a/gcc/testsuite/gcc.dg/tree-ssa/modref-11.c +++ b/gcc/testsuite/gcc.dg/tree-ssa/modref-11.c @@ -10,4 +10,4 @@ find_last (struct linkedlist *l) l = l->next; return l; } -/* { dg-final { scan-tree-dump "noclobber noescape nodirectescape" "modref1"} } */ +/* { dg-final { scan-tree-dump "parm 0 flags: no_direct_clobber no_indirect_clobber no_direct_escape no_indirect_escape" "modref1"} } */ diff --git a/gcc/testsuite/gcc.dg/tree-ssa/modref-13.c b/gcc/testsuite/gcc.dg/tree-ssa/modref-13.c new file mode 100644 index 00000000000..5a5750425d2 --- /dev/null +++ b/gcc/testsuite/gcc.dg/tree-ssa/modref-13.c @@ -0,0 +1,21 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -fdump-tree-release_ssa" } */ +struct wrap { + void **array; +}; +__attribute__ ((noinline)) +void +write_array (struct wrap *ptr) +{ + ptr->array[0]=0; +} +int +test () +{ + void *arrayval; + struct wrap w = {&arrayval}; + write_array (&w); + return w.array == &arrayval; +} +/* We should deterine that write_array writes to PTR only indirectly. */ +/* { dg-final { scan-tree-dump "return 1" "releae_ssa" } } */ diff --git a/gcc/testsuite/gcc.dg/tree-ssa/modref-5.c b/gcc/testsuite/gcc.dg/tree-ssa/modref-5.c index fde31772862..0bee79d769d 100644 --- a/gcc/testsuite/gcc.dg/tree-ssa/modref-5.c +++ b/gcc/testsuite/gcc.dg/tree-ssa/modref-5.c @@ -24,4 +24,4 @@ main() __builtin_abort (); return 0; } -/* { dg-final { scan-tree-dump "parm 1 flags: nodirectescape" "modref1" } } */ +/* { dg-final { scan-tree-dump "parm 1 flags: no_direct_clobber no_direct_escape" "modref1" } } */ diff --git a/gcc/testsuite/gcc.dg/tree-ssa/modref-6.c b/gcc/testsuite/gcc.dg/tree-ssa/modref-6.c index 2d97a4903ff..7146389a5b4 100644 --- a/gcc/testsuite/gcc.dg/tree-ssa/modref-6.c +++ b/gcc/testsuite/gcc.dg/tree-ssa/modref-6.c @@ -28,10 +28,10 @@ int test2() return a; } /* Flags for normal call. */ -/* { dg-final { scan-tree-dump "parm 0 flags: direct noclobber noescape nodirectescape not_returned" "modref1" } } */ +/* { dg-final { scan-tree-dump "parm 0 flags: no_direct_clobber no_indirect_clobber no_direct_escape no_indirect_escape not_returned_directly not_returned_indirectly no_indirect_read" "modref1" } } */ /* Flags for pure call. */ -/* { dg-final { scan-tree-dump "parm 0 flags: direct not_returned" "modref1" } } */ +/* { dg-final { scan-tree-dump "parm 0 flags: not_returned_directly not_returned_indirectly no_indirect_read" "modref1" } } */ /* Flags for const call. */ -/* { dg-final { scan-tree-dump "parm 0 flags: not_returned" "modref1" } } */ +/* { dg-final { scan-tree-dump "parm 0 flags: not_returned_directly" "modref1" } } */ /* Overall we want to make "int a" non escaping. */ /* { dg-final { scan-tree-dump "return 42" "optimized" } } */ diff --git a/gcc/tree-core.h b/gcc/tree-core.h index f0c65a25f07..8ab119dc9a2 100644 --- a/gcc/tree-core.h +++ b/gcc/tree-core.h @@ -97,32 +97,29 @@ struct die_struct; #define ECF_COLD (1 << 15) /* Call argument flags. */ -/* Nonzero if the argument is not dereferenced recursively, thus only - directly reachable memory is read or written. */ -#define EAF_DIRECT (1 << 0) - -/* Nonzero if memory reached by the argument is not clobbered. */ -#define EAF_NOCLOBBER (1 << 1) - -/* Nonzero if the argument does not escape. */ -#define EAF_NOESCAPE (1 << 2) /* Nonzero if the argument is not used by the function. */ -#define EAF_UNUSED (1 << 3) +#define EAF_UNUSED (1 << 1) -/* Nonzero if the argument itself does not escape but memory - referenced by it can escape. */ -#define EAF_NODIRECTESCAPE (1 << 4) +/* Following flags come in pairs. First one is about direct dereferences + from the parameter, while the second is about memory reachable by + recursive dereferences. */ + +/* Nonzero if memory reached by the argument is not clobbered. */ +#define EAF_NO_DIRECT_CLOBBER (1 << 2) +#define EAF_NO_INDIRECT_CLOBBER (1 << 3) + +/* Nonzero if the argument does not escape. */ +#define EAF_NO_DIRECT_ESCAPE (1 << 4) +#define EAF_NO_INDIRECT_ESCAPE (1 << 5) /* 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) +#define EAF_NOT_RETURNED_INDIRECTLY (1 << 7) /* Nonzero if the argument is not read. */ -#define EAF_NOREAD (1 << 7) +#define EAF_NO_DIRECT_READ (1 << 8) +#define EAF_NO_INDIRECT_READ (1 << 9) /* Call return flags. */ /* Mask for the argument number that is returned. Lower two bits of diff --git a/gcc/tree-ssa-alias.c b/gcc/tree-ssa-alias.c index eabf6805f2b..17ff6bb582c 100644 --- a/gcc/tree-ssa-alias.c +++ b/gcc/tree-ssa-alias.c @@ -2874,7 +2874,7 @@ process_args: tree op = gimple_call_arg (call, i); int flags = gimple_call_arg_flags (call, i); - if (flags & (EAF_UNUSED | EAF_NOREAD)) + if (flags & (EAF_UNUSED | EAF_NO_DIRECT_READ)) continue; if (TREE_CODE (op) == WITH_SIZE_EXPR) diff --git a/gcc/tree-ssa-structalias.c b/gcc/tree-ssa-structalias.c index c70f5af8949..153ddf57a61 100644 --- a/gcc/tree-ssa-structalias.c +++ b/gcc/tree-ssa-structalias.c @@ -4060,48 +4060,117 @@ static void handle_call_arg (gcall *stmt, tree arg, vec *results, int flags, int callescape_id, bool writes_global_memory) { + int relevant_indirect_flags = EAF_NO_INDIRECT_CLOBBER | EAF_NO_INDIRECT_READ + | EAF_NO_INDIRECT_ESCAPE; + int relevant_flags = relevant_indirect_flags + | EAF_NO_DIRECT_CLOBBER + | EAF_NO_DIRECT_READ + | EAF_NO_DIRECT_ESCAPE; + if (gimple_call_lhs (stmt)) + { + relevant_flags |= EAF_NOT_RETURNED_DIRECTLY | EAF_NOT_RETURNED_INDIRECTLY; + relevant_indirect_flags |= EAF_NOT_RETURNED_INDIRECTLY; + + /* If value is never read from it can not be returned indirectly + (except through the escape solution). + For all flags we get these implications right except for + not_returned because we miss return functions in ipa-prop. */ + + if (flags & EAF_NO_DIRECT_READ) + flags |= EAF_NOT_RETURNED_INDIRECTLY; + } + /* If the argument is not used we can ignore it. Similarly argument is invisile for us if it not clobbered, does not escape, is not read and can not be returned. */ - if ((flags & EAF_UNUSED) - || ((flags & (EAF_NOCLOBBER | EAF_NOESCAPE | EAF_NOREAD - | EAF_NOT_RETURNED)) - == (EAF_NOCLOBBER | EAF_NOESCAPE | EAF_NOREAD - | EAF_NOT_RETURNED))) + if ((flags & EAF_UNUSED) || ((flags & relevant_flags) == relevant_flags)) return; + /* Produce varinfo for direct accesses to ARG. */ varinfo_t tem = new_var_info (NULL_TREE, "callarg", true); tem->is_reg_var = true; make_constraint_to (tem->id, arg); make_any_offset_constraints (tem); - if (!(flags & EAF_DIRECT)) - make_transitive_closure_constraints (tem); + bool callarg_transitive = false; - if (!(flags & EAF_NOT_RETURNED)) + /* As an compile time optimization if we make no difference between + direct and indirect accesses make arg transitively closed. + This avoids the need to build indir arg and do everything twice. */ + if (((flags & EAF_NO_INDIRECT_CLOBBER) != 0) + == ((flags & EAF_NO_DIRECT_CLOBBER) != 0) + && (((flags & EAF_NO_INDIRECT_READ) != 0) + == ((flags & EAF_NO_DIRECT_READ) != 0)) + && (((flags & EAF_NO_INDIRECT_ESCAPE) != 0) + == ((flags & EAF_NO_DIRECT_ESCAPE) != 0)) + && (((flags & EAF_NOT_RETURNED_INDIRECTLY) != 0) + == ((flags & EAF_NOT_RETURNED_DIRECTLY) != 0))) { - struct constraint_expr cexpr; - cexpr.var = tem->id; - if (flags & EAF_NOT_RETURNED_DIRECTLY) - { - cexpr.type = DEREF; - cexpr.offset = UNKNOWN_OFFSET; - } - else - { - cexpr.type = SCALAR; - cexpr.offset = 0; - } - results->safe_push (cexpr); + make_transitive_closure_constraints (tem); + callarg_transitive = true; + gcc_checking_assert (!(flags & EAF_NO_DIRECT_READ)); } - if (!(flags & EAF_NOREAD)) + /* If necessary, produce varinfo for indirect accesses to ARG. */ + varinfo_t indir_tem = NULL; + if (!callarg_transitive + && (flags & relevant_indirect_flags) != relevant_indirect_flags) + { + struct constraint_expr lhs, rhs; + indir_tem = new_var_info (NULL_TREE, "indircallarg", true); + indir_tem->is_reg_var = true; + + /* indir_term = *tem. */ + lhs.type = SCALAR; + lhs.var = indir_tem->id; + lhs.offset = 0; + + rhs.type = DEREF; + rhs.var = tem->id; + rhs.offset = UNKNOWN_OFFSET; + process_constraint (new_constraint (lhs, rhs)); + + make_any_offset_constraints (indir_tem); + + /* If we do not read indirectly there is no need for transitive closure. + We know there is only one level of indirection. */ + if (!(flags & EAF_NO_INDIRECT_READ)) + make_transitive_closure_constraints (indir_tem); + gcc_checking_assert (!(flags & EAF_NO_DIRECT_READ)); + } + + if (gimple_call_lhs (stmt)) + { + if (!(flags & EAF_NOT_RETURNED_DIRECTLY)) + { + struct constraint_expr cexpr; + cexpr.var = tem->id; + cexpr.type = SCALAR; + cexpr.offset = 0; + results->safe_push (cexpr); + } + if (!callarg_transitive & !(flags & EAF_NOT_RETURNED_INDIRECTLY)) + { + struct constraint_expr cexpr; + cexpr.var = indir_tem->id; + cexpr.type = SCALAR; + cexpr.offset = 0; + results->safe_push (cexpr); + } + } + + if (!(flags & EAF_NO_DIRECT_READ)) { varinfo_t uses = get_call_use_vi (stmt); make_copy_constraint (uses, tem->id); + if (!callarg_transitive & !(flags & EAF_NO_INDIRECT_READ)) + make_copy_constraint (uses, indir_tem->id); } + else + /* To read indirectly we need to read directly. */ + gcc_checking_assert (flags & EAF_NO_INDIRECT_READ); - if (!(flags & EAF_NOCLOBBER)) + if (!(flags & EAF_NO_DIRECT_CLOBBER)) { struct constraint_expr lhs, rhs; @@ -4118,8 +4187,25 @@ handle_call_arg (gcall *stmt, tree arg, vec *results, int flags, /* callclobbered = arg. */ make_copy_constraint (get_call_clobber_vi (stmt), tem->id); } + if (!callarg_transitive & !(flags & EAF_NO_INDIRECT_CLOBBER)) + { + struct constraint_expr lhs, rhs; - if (!(flags & (EAF_NOESCAPE | EAF_NODIRECTESCAPE))) + /* *indir_arg = callescape. */ + lhs.type = DEREF; + lhs.var = indir_tem->id; + lhs.offset = 0; + + rhs.type = SCALAR; + rhs.var = callescape_id; + rhs.offset = 0; + process_constraint (new_constraint (lhs, rhs)); + + /* callclobbered = indir_arg. */ + make_copy_constraint (get_call_clobber_vi (stmt), indir_tem->id); + } + + if (!(flags & (EAF_NO_DIRECT_ESCAPE | EAF_NO_INDIRECT_ESCAPE))) { struct constraint_expr lhs, rhs; @@ -4136,18 +4222,18 @@ handle_call_arg (gcall *stmt, tree arg, vec *results, int flags, if (writes_global_memory) make_escape_constraint (arg); } - else if (!(flags & EAF_NOESCAPE)) + else if (!callarg_transitive & !(flags & EAF_NO_INDIRECT_ESCAPE)) { struct constraint_expr lhs, rhs; - /* callescape = *(arg + UNKNOWN); */ + /* callescape = *(indir_arg + UNKNOWN); */ lhs.var = callescape_id; lhs.offset = 0; lhs.type = SCALAR; - rhs.var = tem->id; - rhs.offset = UNKNOWN_OFFSET; - rhs.type = DEREF; + rhs.var = indir_tem->id; + rhs.offset = 0; + rhs.type = SCALAR; process_constraint (new_constraint (lhs, rhs)); if (writes_global_memory) @@ -4264,20 +4350,22 @@ handle_rhs_call (gcall *stmt, vec *results, && TREE_ADDRESSABLE (TREE_TYPE (gimple_call_lhs (stmt)))) { int flags = gimple_call_retslot_flags (stmt); - if ((flags & (EAF_NOESCAPE | EAF_NOT_RETURNED)) - != (EAF_NOESCAPE | EAF_NOT_RETURNED)) + const int relevant_flags = EAF_NO_DIRECT_ESCAPE + | EAF_NOT_RETURNED_DIRECTLY; + + if (!(flags & EAF_UNUSED) && (flags & relevant_flags) != relevant_flags) { auto_vec tmpc; get_constraint_for_address_of (gimple_call_lhs (stmt), &tmpc); - if (!(flags & (EAF_NOESCAPE | EAF_NODIRECTESCAPE))) + if (!(flags & EAF_NO_DIRECT_ESCAPE)) { make_constraints_to (callescape->id, tmpc); if (writes_global_memory) make_constraints_to (escaped_id, tmpc); } - if (!(flags & EAF_NOT_RETURNED)) + if (!(flags & EAF_NOT_RETURNED_DIRECTLY)) { struct constraint_expr *c; unsigned i; diff --git a/gcc/tree-ssa-uninit.c b/gcc/tree-ssa-uninit.c index d67534f22a8..1df0bcc42c0 100644 --- a/gcc/tree-ssa-uninit.c +++ b/gcc/tree-ssa-uninit.c @@ -744,7 +744,8 @@ maybe_warn_pass_by_reference (gcall *stmt, wlimits &wlims) wlims.always_executed = false; /* Ignore args we are not going to read from. */ - if (gimple_call_arg_flags (stmt, argno - 1) & (EAF_UNUSED | EAF_NOREAD)) + if (gimple_call_arg_flags (stmt, argno - 1) + & (EAF_UNUSED | EAF_NO_DIRECT_READ)) continue; tree arg = gimple_call_arg (stmt, argno - 1);