Mercurial > hg > CbC > CbC_gcc
diff gcc/tree-ssa-live.c @ 67:f6334be47118
update gcc from gcc-4.6-20100522 to gcc-4.6-20110318
author | nobuyasu <dimolto@cr.ie.u-ryukyu.ac.jp> |
---|---|
date | Tue, 22 Mar 2011 17:18:12 +0900 |
parents | b7f97abdc517 |
children | 04ced10e8804 |
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--- a/gcc/tree-ssa-live.c Tue May 25 18:58:51 2010 +0900 +++ b/gcc/tree-ssa-live.c Tue Mar 22 17:18:12 2011 +0900 @@ -24,16 +24,16 @@ #include "coretypes.h" #include "tm.h" #include "tree.h" -#include "diagnostic.h" #include "tree-pretty-print.h" #include "gimple-pretty-print.h" #include "bitmap.h" #include "tree-flow.h" #include "tree-dump.h" #include "tree-ssa-live.h" -#include "toplev.h" +#include "diagnostic-core.h" #include "debug.h" #include "flags.h" +#include "gimple.h" #ifdef ENABLE_CHECKING static void verify_live_on_entry (tree_live_info_p); @@ -361,13 +361,13 @@ && (b = TREE_BLOCK (t)) != NULL) TREE_USED (b) = true; - /* Ignore TREE_ORIGINAL for TARGET_MEM_REFS, as well as other - fields that do not contain vars. */ + /* Ignore TMR_OFFSET and TMR_STEP for TARGET_MEM_REFS, as those + fields do not contain vars. */ if (TREE_CODE (t) == TARGET_MEM_REF) { - mark_all_vars_used (&TMR_SYMBOL (t), data); mark_all_vars_used (&TMR_BASE (t), data); mark_all_vars_used (&TMR_INDEX (t), data); + mark_all_vars_used (&TMR_INDEX2 (t), data); *walk_subtrees = 0; return NULL; } @@ -376,13 +376,18 @@ eliminated as unused. */ if (TREE_CODE (t) == VAR_DECL) { - if (data != NULL && bitmap_bit_p ((bitmap) data, DECL_UID (t))) - { - bitmap_clear_bit ((bitmap) data, DECL_UID (t)); - mark_all_vars_used (&DECL_INITIAL (t), data); - } + if (data != NULL && bitmap_clear_bit ((bitmap) data, DECL_UID (t))) + mark_all_vars_used (&DECL_INITIAL (t), data); set_is_used (t); } + /* remove_unused_scope_block_p requires information about labels + which are not DECL_IGNORED_P to tell if they might be used in the IL. */ + if (TREE_CODE (t) == LABEL_DECL) + /* Although the TREE_USED values that the frontend uses would be + acceptable (albeit slightly over-conservative) for our purposes, + init_vars_expansion clears TREE_USED for LABEL_DECLs too, so we + must re-compute it here. */ + TREE_USED (t) = 1; if (IS_TYPE_OR_DECL_P (t)) *walk_subtrees = 0; @@ -427,7 +432,7 @@ for (t = &BLOCK_VARS (scope); *t; t = next) { - next = &TREE_CHAIN (*t); + next = &DECL_CHAIN (*t); /* Debug info of nested function refers to the block of the function. We might stil call it even if all statements @@ -448,10 +453,13 @@ else if (TREE_CODE (*t) == VAR_DECL && DECL_HAS_VALUE_EXPR_P (*t)) unused = false; - /* Remove everything we don't generate debug info for. */ - else if (DECL_IGNORED_P (*t)) + /* Remove everything we don't generate debug info for. + Don't remove larger vars though, because BLOCK_VARS are + used also during expansion to determine which variables + might share stack space. */ + else if (DECL_IGNORED_P (*t) && is_gimple_reg (*t)) { - *t = TREE_CHAIN (*t); + *t = DECL_CHAIN (*t); next = t; } @@ -460,7 +468,20 @@ Exception are the scope blocks not containing any instructions at all so user can't get into the scopes at first place. */ else if ((ann = var_ann (*t)) != NULL - && ann->used) + && is_used_p (*t)) + unused = false; + else if (TREE_CODE (*t) == LABEL_DECL && TREE_USED (*t)) + /* For labels that are still used in the IL, the decision to + preserve them must not depend DEBUG_INFO_LEVEL, otherwise we + risk having different ordering in debug vs. non-debug builds + during inlining or versioning. + A label appearing here (we have already checked DECL_IGNORED_P) + should not be used in the IL unless it has been explicitly used + before, so we use TREE_USED as an approximation. */ + /* In principle, we should do the same here as for the debug case + below, however, when debugging, there might be additional nested + levels that keep an upper level with a label live, so we have to + force this block to be considered used, too. */ unused = false; /* When we are not doing full debug info, we however can keep around @@ -472,16 +493,21 @@ can be considered dead. We only want to keep around blocks user can breakpoint into and ask about value of optimized out variables. - Similarly we need to keep around types at least until all variables of - all nested blocks are gone. We track no information on whether given - type is used or not. */ + Similarly we need to keep around types at least until all + variables of all nested blocks are gone. We track no + information on whether given type is used or not, so we have + to keep them even when not emitting debug information, + otherwise we may end up remapping variables and their (local) + types in different orders depending on whether debug + information is being generated. */ - else if (debug_info_level == DINFO_LEVEL_NORMAL + else if (TREE_CODE (*t) == TYPE_DECL + || debug_info_level == DINFO_LEVEL_NORMAL || debug_info_level == DINFO_LEVEL_VERBOSE) ; else { - *t = TREE_CHAIN (*t); + *t = DECL_CHAIN (*t); next = t; } } @@ -604,16 +630,14 @@ } } fprintf (file, " \n"); - for (var = BLOCK_VARS (scope); var; var = TREE_CHAIN (var)) + for (var = BLOCK_VARS (scope); var; var = DECL_CHAIN (var)) { bool used = false; - var_ann_t ann; - if ((ann = var_ann (var)) - && ann->used) - used = true; + if (var_ann (var)) + used = is_used_p (var); - fprintf (file, "%*s",indent, ""); + fprintf (file, "%*s", indent, ""); print_generic_decl (file, var, flags); fprintf (file, "%s\n", used ? "" : " (unused)"); } @@ -632,7 +656,7 @@ /* Dump the tree of lexical scopes starting at SCOPE to stderr. FLAGS is as in print_generic_expr. */ -void +DEBUG_FUNCTION void debug_scope_block (tree scope, int flags) { dump_scope_block (stderr, 0, scope, flags); @@ -652,7 +676,7 @@ /* Dump the tree of lexical scopes of current_function_decl to stderr. FLAGS is as in print_generic_expr. */ -void +DEBUG_FUNCTION void debug_scope_blocks (int flags) { dump_scope_blocks (stderr, flags); @@ -664,10 +688,11 @@ remove_unused_locals (void) { basic_block bb; - tree t, *cell; + tree var, t; referenced_var_iterator rvi; var_ann_t ann; bitmap global_unused_vars = NULL; + unsigned srcidx, dstidx, num; /* Removing declarations from lexical blocks when not optimizing is not only a waste of time, it actually causes differences in stack @@ -675,11 +700,13 @@ if (!optimize) return; + timevar_push (TV_REMOVE_UNUSED); + mark_scope_block_unused (DECL_INITIAL (current_function_decl)); /* Assume all locals are unused. */ - FOR_EACH_REFERENCED_VAR (t, rvi) - var_ann (t)->used = false; + FOR_EACH_REFERENCED_VAR (cfun, t, rvi) + clear_is_used (t); /* Walk the CFG marking all referenced symbols. */ FOR_EACH_BB (bb) @@ -734,13 +761,13 @@ cfun->has_local_explicit_reg_vars = false; /* Remove unmarked local vars from local_decls. */ - for (cell = &cfun->local_decls; *cell; ) + num = VEC_length (tree, cfun->local_decls); + for (srcidx = 0, dstidx = 0; srcidx < num; srcidx++) { - tree var = TREE_VALUE (*cell); - + var = VEC_index (tree, cfun->local_decls, srcidx); if (TREE_CODE (var) != FUNCTION_DECL && (!(ann = var_ann (var)) - || !ann->used)) + || !is_used_p (var))) { if (is_global_var (var)) { @@ -749,58 +776,57 @@ bitmap_set_bit (global_unused_vars, DECL_UID (var)); } else - { - *cell = TREE_CHAIN (*cell); - continue; - } + continue; } else if (TREE_CODE (var) == VAR_DECL && DECL_HARD_REGISTER (var) && !is_global_var (var)) cfun->has_local_explicit_reg_vars = true; - cell = &TREE_CHAIN (*cell); + + if (srcidx != dstidx) + VEC_replace (tree, cfun->local_decls, dstidx, var); + dstidx++; } + if (dstidx != num) + VEC_truncate (tree, cfun->local_decls, dstidx); /* Remove unmarked global vars from local_decls. */ if (global_unused_vars != NULL) { - for (t = cfun->local_decls; t; t = TREE_CHAIN (t)) - { - tree var = TREE_VALUE (t); + tree var; + unsigned ix; + FOR_EACH_LOCAL_DECL (cfun, ix, var) + if (TREE_CODE (var) == VAR_DECL + && is_global_var (var) + && (ann = var_ann (var)) != NULL + && is_used_p (var)) + mark_all_vars_used (&DECL_INITIAL (var), global_unused_vars); - if (TREE_CODE (var) == VAR_DECL - && is_global_var (var) - && (ann = var_ann (var)) != NULL - && ann->used) - mark_all_vars_used (&DECL_INITIAL (var), global_unused_vars); - } - - for (cell = &cfun->local_decls; *cell; ) + num = VEC_length (tree, cfun->local_decls); + for (srcidx = 0, dstidx = 0; srcidx < num; srcidx++) { - tree var = TREE_VALUE (*cell); - + var = VEC_index (tree, cfun->local_decls, srcidx); if (TREE_CODE (var) == VAR_DECL && is_global_var (var) && bitmap_bit_p (global_unused_vars, DECL_UID (var))) - *cell = TREE_CHAIN (*cell); - else - cell = &TREE_CHAIN (*cell); + continue; + + if (srcidx != dstidx) + VEC_replace (tree, cfun->local_decls, dstidx, var); + dstidx++; } + if (dstidx != num) + VEC_truncate (tree, cfun->local_decls, dstidx); BITMAP_FREE (global_unused_vars); } - /* Remove unused variables from REFERENCED_VARs. As a special - exception keep the variables that are believed to be aliased. - Those can't be easily removed from the alias sets and operand - caches. They will be removed shortly after the next may_alias - pass is performed. */ - FOR_EACH_REFERENCED_VAR (t, rvi) + /* Remove unused variables from REFERENCED_VARs. */ + FOR_EACH_REFERENCED_VAR (cfun, t, rvi) if (!is_global_var (t) && TREE_CODE (t) != PARM_DECL && TREE_CODE (t) != RESULT_DECL - && !(ann = var_ann (t))->used - && !ann->is_heapvar - && !TREE_ADDRESSABLE (t)) + && !is_used_p (t) + && !var_ann (t)->is_heapvar) remove_referenced_var (t); remove_unused_scope_block_p (DECL_INITIAL (current_function_decl)); if (dump_file && (dump_flags & TDF_DETAILS)) @@ -808,6 +834,8 @@ fprintf (dump_file, "Scope blocks after cleanups:\n"); dump_scope_blocks (dump_file, dump_flags); } + + timevar_pop (TV_REMOVE_UNUSED); } @@ -1170,6 +1198,94 @@ } } +struct GTY(()) numbered_tree_d +{ + tree t; + int num; +}; +typedef struct numbered_tree_d numbered_tree; + +DEF_VEC_O (numbered_tree); +DEF_VEC_ALLOC_O (numbered_tree, heap); + +/* Compare two declarations references by their DECL_UID / sequence number. + Called via qsort. */ + +static int +compare_decls_by_uid (const void *pa, const void *pb) +{ + const numbered_tree *nt_a = ((const numbered_tree *)pa); + const numbered_tree *nt_b = ((const numbered_tree *)pb); + + if (DECL_UID (nt_a->t) != DECL_UID (nt_b->t)) + return DECL_UID (nt_a->t) - DECL_UID (nt_b->t); + return nt_a->num - nt_b->num; +} + +/* Called via walk_gimple_stmt / walk_gimple_op by dump_enumerated_decls. */ +static tree +dump_enumerated_decls_push (tree *tp, int *walk_subtrees, void *data) +{ + struct walk_stmt_info *wi = (struct walk_stmt_info *) data; + VEC (numbered_tree, heap) **list = (VEC (numbered_tree, heap) **) &wi->info; + numbered_tree nt; + + if (!DECL_P (*tp)) + return NULL_TREE; + nt.t = *tp; + nt.num = VEC_length (numbered_tree, *list); + VEC_safe_push (numbered_tree, heap, *list, &nt); + *walk_subtrees = 0; + return NULL_TREE; +} + +/* Find all the declarations used by the current function, sort them by uid, + and emit the sorted list. Each declaration is tagged with a sequence + number indicating when it was found during statement / tree walking, + so that TDF_NOUID comparisons of anonymous declarations are still + meaningful. Where a declaration was encountered more than once, we + emit only the sequence number of the first encounter. + FILE is the dump file where to output the list and FLAGS is as in + print_generic_expr. */ +void +dump_enumerated_decls (FILE *file, int flags) +{ + basic_block bb; + struct walk_stmt_info wi; + VEC (numbered_tree, heap) *decl_list = VEC_alloc (numbered_tree, heap, 40); + + memset (&wi, '\0', sizeof (wi)); + wi.info = (void*) decl_list; + FOR_EACH_BB (bb) + { + gimple_stmt_iterator gsi; + + for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi)) + if (!is_gimple_debug (gsi_stmt (gsi))) + walk_gimple_stmt (&gsi, NULL, dump_enumerated_decls_push, &wi); + } + decl_list = (VEC (numbered_tree, heap) *) wi.info; + VEC_qsort (numbered_tree, decl_list, compare_decls_by_uid); + if (VEC_length (numbered_tree, decl_list)) + { + unsigned ix; + numbered_tree *ntp; + tree last = NULL_TREE; + + fprintf (file, "Declarations used by %s, sorted by DECL_UID:\n", + current_function_name ()); + FOR_EACH_VEC_ELT (numbered_tree, decl_list, ix, ntp) + { + if (ntp->t == last) + continue; + fprintf (file, "%d: ", ntp->num); + print_generic_decl (file, ntp->t, flags); + fprintf (file, "\n"); + last = ntp->t; + } + } + VEC_free (numbered_tree, heap, decl_list); +} #ifdef ENABLE_CHECKING /* Verify that SSA_VAR is a non-virtual SSA_NAME. */