On Fri, Jan 15, 2016 at 11:27 AM, Alan Lawrence <alan.lawre...@foss.arm.com> wrote: > On 24/12/15 11:53, Alan Lawrence wrote: >> >> Here's a new version that fixes the gcc.dg/guality/pr54970.c failures seen >> on >> aarch64 and powerpc64. Prior to SRA handling constant pool decls, >> -fdump-tree-esra-details (at -O1 -g) had shown: >> <bb 2>: >> a = *.LC0; >> # DEBUG a$0 => MEM[(int[3] *)&*.LC0] >> a$4_3 = MEM[(int[3] *)&*.LC0 + 4B]; >> # DEBUG a$4 => a$4_3 >> a$8_4 = MEM[(int[3] *)&*.LC0 + 8B]; >> >> The previous patch changed this to: >> <bb 2>: >> SR.5_3 = *.LC0[0]; >> SR.6_4 = *.LC0[1]; >> SR.7_19 = *.LC0[2]; >> SR.8_21 = *.LC1[0]; >> SR.9_22 = *.LC1[1]; >> SR.10_23 = *.LC1[2]; >> # DEBUG a$0 => NULL // Note here >> a$4_24 = SR.6_4; >> # DEBUG a$4 => a$4_24 >> a$8_25 = SR.7_19; >> >> Turns out the DEBUG a$0 => NULL was produced in >> load_assign_lhs_subreplacements: >> >> if (lacc && lacc->grp_to_be_debug_replaced) >> { >> gdebug *ds; >> tree drhs; >> struct access *racc = find_access_in_subtree (sad->top_racc, >> offset, >> lacc->size); >> >> if (racc && racc->grp_to_be_replaced) >> { >> if (racc->grp_write) >> drhs = get_access_replacement (racc); >> else >> drhs = NULL; // <=== HERE >> } >> ... >> ds = gimple_build_debug_bind (get_access_replacement (lacc), >> drhs, gsi_stmt >> (sad->old_gsi)); >> >> Prior to the patch, we'd skipped around load_assign_lhs_subreplacements, >> because >> access_has_children_p(racc) (for racc = *.LC0) didn't hold in >> sra_modify_assign. >> >> I also added a constant_decl_p function, combining the two checks, plus >> some >> testcase fixes. >> >> Bootstrapped + check-gcc,g++ on x86_64, ARM, AArch64, >> also on powerpc64{,le}-none-linux-gnu *in combination with the other >> patches >> in the series* (I haven't tested the individual patches on PPC), >> plus Ada on ARM and x86_64. >> >> gcc/ChangeLog: >> >> PR target/63679 >> * tree-sra.c (disqualified_constants, constant_decl_p): New. >> (sra_initialize): Allocate disqualified_constants. >> (sra_deinitialize): Free disqualified_constants. >> (disqualify_candidate): Update disqualified_constants when >> appropriate. >> (create_access): Scan for constant-pool entries as we go along. >> (scalarizable_type_p): Add check against >> type_contains_placeholder_p. >> (maybe_add_sra_candidate): Allow constant-pool entries. >> (load_assign_lhs_subreplacements): Bind debug for constant pool >> vars. >> (initialize_constant_pool_replacements): New. >> (sra_modify_assign): Avoid mangling assignments created by >> previous, >> and don't generate writes into constant pool. >> (sra_modify_function_body): Call >> initialize_constant_pool_replacements. >> >> gcc/testsuite/ChangeLog: >> >> * gcc.dg/tree-ssa/sra-17.c: New. >> * gcc.dg/tree-ssa/sra-18.c: New. > > > Ping.
Ok. Thanks, Richard. > (The next bit is false, unless you force SRA to happen more widely, but all > the above stands) > >> This also fixes a bunch of other guality tests on AArch64 that were >> failing >> prior to the patch series, and another bunch on PowerPC64 (bigendian >> -m32), listed below. > >> >> >> Tests fixed on aarch64-none-linux-gnu: >> >> gcc.dg/guality/pr54970.c -O1 line 15 *p == 3 >> gcc.dg/guality/pr54970.c -O1 line 15 *q == 2 >> gcc.dg/guality/pr54970.c -O1 line 20 *p == 13 >> gcc.dg/guality/pr54970.c -O1 line 20 *q == 2 >> gcc.dg/guality/pr54970.c -O1 line 25 *p == 13 >> gcc.dg/guality/pr54970.c -O1 line 25 *q == 12 >> gcc.dg/guality/pr54970.c -O1 line 31 *p == 6 >> gcc.dg/guality/pr54970.c -O1 line 31 *q == 5 >> gcc.dg/guality/pr54970.c -O1 line 36 *p == 26 >> gcc.dg/guality/pr54970.c -O1 line 36 *q == 5 >> gcc.dg/guality/pr54970.c -O1 line 45 *p == 26 >> gcc.dg/guality/pr54970.c -O1 line 45 *q == 25 >> gcc.dg/guality/pr54970.c -O1 line 45 p[-1] == 25 >> gcc.dg/guality/pr54970.c -O1 line 45 p[-2] == 4 >> gcc.dg/guality/pr54970.c -O1 line 45 q[-1] == 4 >> gcc.dg/guality/pr54970.c -O1 line 45 q[1] == 26 >> gcc.dg/guality/pr56154-1.c -O1 line pr56154-1.c:20 x.a == 6 >> gcc.dg/guality/pr59776.c -O1 line pr59776.c:17 s1.f == 5.0 >> gcc.dg/guality/pr59776.c -O1 line pr59776.c:17 s1.g == 6.0 >> gcc.dg/guality/pr59776.c -O1 line pr59776.c:17 s2.f == 0.0 >> gcc.dg/guality/pr59776.c -O1 line pr59776.c:17 s2.g == 6.0 >> gcc.dg/guality/pr59776.c -O1 line pr59776.c:20 s1.f == 5.0 >> gcc.dg/guality/pr59776.c -O1 line pr59776.c:20 s1.g == 6.0 >> gcc.dg/guality/pr59776.c -O1 line pr59776.c:20 s2.f == 5.0 >> gcc.dg/guality/pr59776.c -O1 line pr59776.c:20 s2.g == 6.0 >> gcc.dg/guality/sra-1.c -O1 line 21 a.j == 14 >> gcc.dg/guality/sra-1.c -O1 line 32 a[1] == 14 >> gcc.dg/guality/sra-1.c -O1 line 43 a.i == 4 >> gcc.dg/guality/sra-1.c -O1 line 43 a.j == 14 >> (and other optimization levels) >> On ppc64 bigendian, with the rest of the series (but I expect it's this >> patch): >> unix/-m32: gcc.dg/guality/pr54970.c -O1 line 15 a[0] == 1 >> unix/-m32: gcc.dg/guality/pr54970.c -O1 line 20 a[0] == 1 >> unix/-m32: gcc.dg/guality/pr54970.c -O1 line 25 a[0] == 1 >> unix/-m32: gcc.dg/guality/pr54970.c -O1 line 31 a[0] == 4 >> unix/-m32: gcc.dg/guality/pr54970.c -O1 line 36 a[0] == 4 >> unix/-m32: gcc.dg/guality/pr54970.c -O1 line 45 a[0] == 4 >> unix/-m32: gcc.dg/guality/pr54970.c -O1 line 45 p[-2] == 4 >> unix/-m32: gcc.dg/guality/pr54970.c -O1 line 45 q[-1] == 4 >> (again, and other optimization levels). > > > Cheers, Alan > > >> --- >> gcc/testsuite/gcc.dg/tree-ssa/sra-17.c | 19 ++++++ >> gcc/testsuite/gcc.dg/tree-ssa/sra-18.c | 28 +++++++++ >> gcc/tree-sra.c | 104 >> +++++++++++++++++++++++++++++++-- >> 3 files changed, 147 insertions(+), 4 deletions(-) >> create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/sra-17.c >> create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/sra-18.c >> >> diff --git a/gcc/testsuite/gcc.dg/tree-ssa/sra-17.c >> b/gcc/testsuite/gcc.dg/tree-ssa/sra-17.c >> new file mode 100644 >> index 0000000..25667f4 >> --- /dev/null >> +++ b/gcc/testsuite/gcc.dg/tree-ssa/sra-17.c >> @@ -0,0 +1,19 @@ >> +/* { dg-do run { target { aarch64*-*-* alpha*-*-* arm*-*-* hppa*-*-* >> powerpc*-*-* s390*-*-* } } } */ >> +/* { dg-options "-O2 -fdump-tree-esra --param >> sra-max-scalarization-size-Ospeed=32" } */ >> + >> +extern void abort (void); >> + >> +int >> +main (int argc, char **argv) >> +{ >> + long a[4] = { 7, 19, 11, 255 }; >> + int tot = 0; >> + for (int i = 0; i < 4; i++) >> + tot = (tot*256) + a[i]; >> + if (tot == 0x07130bff) >> + return 0; >> + abort (); >> +} >> + >> +/* { dg-final { scan-tree-dump-times "Removing load: a = \\\*.LC0;" 1 >> "esra" } } */ >> +/* { dg-final { scan-tree-dump-times "SR.\[0-9_\]+ = \\\*.LC0\\\[" 4 >> "esra" } } */ >> diff --git a/gcc/testsuite/gcc.dg/tree-ssa/sra-18.c >> b/gcc/testsuite/gcc.dg/tree-ssa/sra-18.c >> new file mode 100644 >> index 0000000..609fb11 >> --- /dev/null >> +++ b/gcc/testsuite/gcc.dg/tree-ssa/sra-18.c >> @@ -0,0 +1,28 @@ >> +/* { dg-do run { target { aarch64*-*-* alpha*-*-* arm*-*-* hppa*-*-* >> powerpc*-*-* s390*-*-* } } } */ >> +/* { dg-options "-O2 -fdump-tree-esra --param >> sra-max-scalarization-size-Ospeed=32" } */ >> + >> +extern void abort (void); >> +struct foo { long x; }; >> + >> +struct bar { struct foo f[2]; }; >> + >> +struct baz { struct bar b[2]; }; >> + >> +int >> +main (int argc, char **argv) >> +{ >> + struct baz a = { { { { { 4 }, { 5 } } }, { { { 6 }, { 7 } } } } }; >> + int tot = 0; >> + for (int i = 0; i < 2; i++) >> + for (int j = 0; j < 2; j++) >> + tot = (tot*256) + a.b[i].f[j].x; >> + if (tot == 0x04050607) >> + return 0; >> + abort (); >> +} >> + >> +/* { dg-final { scan-tree-dump-times "Removing load: a = \\\*.LC0;" 1 >> "esra" } } */ >> +/* { dg-final { scan-tree-dump-times "SR.\[0-9_\]+ = >> \\\*.LC0\\.b\\\[0\\\]\\.f\\\[0\\\]\\.x" 1 "esra" } } */ >> +/* { dg-final { scan-tree-dump-times "SR.\[0-9_\]+ = >> \\\*.LC0\\.b\\\[0\\\]\\.f\\\[1\\\]\\.x" 1 "esra" } } */ >> +/* { dg-final { scan-tree-dump-times "SR.\[0-9_\]+ = >> \\\*.LC0\\.b\\\[1\\\]\\.f\\\[0\\\]\\.x" 1 "esra" } } */ >> +/* { dg-final { scan-tree-dump-times "SR.\[0-9_\]+ = >> \\\*.LC0\\.b\\\[1\\\]\\.f\\\[1\\\]\\.x" 1 "esra" } } */ >> diff --git a/gcc/tree-sra.c b/gcc/tree-sra.c >> index c4fea5b..77a2e49 100644 >> --- a/gcc/tree-sra.c >> +++ b/gcc/tree-sra.c >> @@ -328,6 +328,10 @@ candidate (unsigned uid) >> those which cannot be (because they are and need be used as a whole). >> */ >> static bitmap should_scalarize_away_bitmap, >> cannot_scalarize_away_bitmap; >> >> +/* Bitmap of candidates in the constant pool, which cannot be scalarized >> + because this would produce non-constant expressions (e.g. Ada). */ >> +static bitmap disqualified_constants; >> + >> /* Obstack for creation of fancy names. */ >> static struct obstack name_obstack; >> >> @@ -652,6 +656,7 @@ sra_initialize (void) >> (vec_safe_length (cfun->local_decls) / 2); >> should_scalarize_away_bitmap = BITMAP_ALLOC (NULL); >> cannot_scalarize_away_bitmap = BITMAP_ALLOC (NULL); >> + disqualified_constants = BITMAP_ALLOC (NULL); >> gcc_obstack_init (&name_obstack); >> base_access_vec = new hash_map<tree, auto_vec<access_p> >; >> memset (&sra_stats, 0, sizeof (sra_stats)); >> @@ -670,6 +675,7 @@ sra_deinitialize (void) >> candidates = NULL; >> BITMAP_FREE (should_scalarize_away_bitmap); >> BITMAP_FREE (cannot_scalarize_away_bitmap); >> + BITMAP_FREE (disqualified_constants); >> access_pool.release (); >> assign_link_pool.release (); >> obstack_free (&name_obstack, NULL); >> @@ -677,6 +683,13 @@ sra_deinitialize (void) >> delete base_access_vec; >> } >> >> +/* Return true if DECL is a VAR_DECL in the constant pool, false >> otherwise. */ >> + >> +static bool constant_decl_p (tree decl) >> +{ >> + return TREE_CODE (decl) == VAR_DECL && DECL_IN_CONSTANT_POOL (decl); >> +} >> + >> /* Remove DECL from candidates for SRA and write REASON to the dump file >> if >> there is one. */ >> static void >> @@ -684,6 +697,8 @@ disqualify_candidate (tree decl, const char *reason) >> { >> if (bitmap_clear_bit (candidate_bitmap, DECL_UID (decl))) >> candidates->remove_elt_with_hash (decl, DECL_UID (decl)); >> + if (constant_decl_p (decl)) >> + bitmap_set_bit (disqualified_constants, DECL_UID (decl)); >> >> if (dump_file && (dump_flags & TDF_DETAILS)) >> { >> @@ -835,8 +850,11 @@ create_access_1 (tree base, HOST_WIDE_INT offset, >> HOST_WIDE_INT size) >> return access; >> } >> >> +static bool maybe_add_sra_candidate (tree); >> + >> /* Create and insert access for EXPR. Return created access, or NULL if >> it is >> - not possible. */ >> + not possible. Also scan for uses of constant pool as we go along and >> add >> + to candidates. */ >> >> static struct access * >> create_access (tree expr, gimple *stmt, bool write) >> @@ -859,6 +877,25 @@ create_access (tree expr, gimple *stmt, bool write) >> else >> ptr = false; >> >> + /* For constant-pool entries, check we can substitute the constant >> value. */ >> + if (constant_decl_p (base) >> + && (sra_mode == SRA_MODE_EARLY_INTRA || sra_mode == >> SRA_MODE_INTRA)) >> + { >> + gcc_assert (!bitmap_bit_p (disqualified_constants, DECL_UID >> (base))); >> + if (expr != base >> + && !is_gimple_reg_type (TREE_TYPE (expr)) >> + && dump_file && (dump_flags & TDF_DETAILS)) >> + { >> + /* This occurs in Ada with accesses to ARRAY_RANGE_REFs, >> + and elements of multidimensional arrays (which are >> + multi-element arrays in their own right). */ >> + fprintf (dump_file, "Allowing non-reg-type load of part" >> + " of constant-pool entry: "); >> + print_generic_expr (dump_file, expr, 0); >> + } >> + maybe_add_sra_candidate (base); >> + } >> + >> if (!DECL_P (base) || !bitmap_bit_p (candidate_bitmap, DECL_UID >> (base))) >> return NULL; >> >> @@ -918,6 +955,8 @@ static bool >> scalarizable_type_p (tree type) >> { >> gcc_assert (!is_gimple_reg_type (type)); >> + if (type_contains_placeholder_p (type)) >> + return false; >> >> switch (TREE_CODE (type)) >> { >> @@ -1852,7 +1891,10 @@ maybe_add_sra_candidate (tree var) >> reject (var, "not aggregate"); >> return false; >> } >> - if (needs_to_live_in_memory (var)) >> + /* Allow constant-pool entries (that "need to live in memory") >> + unless we are doing IPA SRA. */ >> + if (needs_to_live_in_memory (var) >> + && (sra_mode == SRA_MODE_EARLY_IPA || !constant_decl_p (var))) >> { >> reject (var, "needs to live in memory"); >> return false; >> @@ -3113,7 +3155,7 @@ load_assign_lhs_subreplacements (struct access >> *lacc, >> >> if (racc && racc->grp_to_be_replaced) >> { >> - if (racc->grp_write) >> + if (racc->grp_write || constant_decl_p (racc->base)) >> drhs = get_access_replacement (racc); >> else >> drhs = NULL; >> @@ -3272,6 +3314,9 @@ sra_modify_assign (gimple *stmt, >> gimple_stmt_iterator *gsi) >> racc = get_access_for_expr (rhs); >> if (!lacc && !racc) >> return SRA_AM_NONE; >> + /* Avoid modifying initializations of constant-pool replacements. */ >> + if (racc && (racc->replacement_decl == lhs)) >> + return SRA_AM_NONE; >> >> loc = gimple_location (stmt); >> if (lacc && lacc->grp_to_be_replaced) >> @@ -3388,7 +3433,8 @@ sra_modify_assign (gimple *stmt, >> gimple_stmt_iterator *gsi) >> || contains_vce_or_bfcref_p (lhs) >> || stmt_ends_bb_p (stmt)) >> { >> - if (access_has_children_p (racc)) >> + /* No need to copy into a constant-pool, it comes pre-initialized. >> */ >> + if (access_has_children_p (racc) && !constant_decl_p (racc->base)) >> generate_subtree_copies (racc->first_child, rhs, racc->offset, 0, >> 0, >> gsi, false, false, loc); >> if (access_has_children_p (lacc)) >> @@ -3491,6 +3537,54 @@ sra_modify_assign (gimple *stmt, >> gimple_stmt_iterator *gsi) >> } >> } >> >> +/* Set any scalar replacements of values in the constant pool to the >> initial >> + value of the constant. (Constant-pool decls like *.LC0 have >> effectively >> + been initialized before the program starts, we must do the same for >> their >> + replacements.) Thus, we output statements like 'SR.1 = *.LC0[0];' >> into >> + the function's entry block. */ >> + >> +static void >> +initialize_constant_pool_replacements (void) >> +{ >> + gimple_seq seq = NULL; >> + gimple_stmt_iterator gsi = gsi_start (seq); >> + bitmap_iterator bi; >> + unsigned i; >> + >> + EXECUTE_IF_SET_IN_BITMAP (candidate_bitmap, 0, i, bi) >> + if (bitmap_bit_p (should_scalarize_away_bitmap, i) >> + && !bitmap_bit_p (cannot_scalarize_away_bitmap, i)) >> + { >> + tree var = candidate (i); >> + if (!constant_decl_p (var)) >> + continue; >> + vec<access_p> *access_vec = get_base_access_vector (var); >> + if (!access_vec) >> + continue; >> + for (unsigned i = 0; i < access_vec->length (); i++) >> + { >> + struct access *access = (*access_vec)[i]; >> + if (!access->replacement_decl) >> + continue; >> + gassign *stmt = gimple_build_assign ( >> + get_access_replacement (access), unshare_expr >> (access->expr)); >> + if (dump_file && (dump_flags & TDF_DETAILS)) >> + { >> + fprintf (dump_file, "Generating constant initializer: "); >> + print_gimple_stmt (dump_file, stmt, 0, 1); >> + fprintf (dump_file, "\n"); >> + } >> + gsi_insert_after (&gsi, stmt, GSI_NEW_STMT); >> + update_stmt (stmt); >> + } >> + } >> + >> + seq = gsi_seq (gsi); >> + if (seq) >> + gsi_insert_seq_on_edge_immediate ( >> + single_succ_edge (ENTRY_BLOCK_PTR_FOR_FN (cfun)), seq); >> +} >> + >> /* Traverse the function body and all modifications as decided in >> analyze_all_variable_accesses. Return true iff the CFG has been >> changed. */ >> @@ -3501,6 +3595,8 @@ sra_modify_function_body (void) >> bool cfg_changed = false; >> basic_block bb; >> >> + initialize_constant_pool_replacements (); >> + >> FOR_EACH_BB_FN (bb, cfun) >> { >> gimple_stmt_iterator gsi = gsi_start_bb (bb); >> >