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Diffstat (limited to 'gcc-4.2.1-5666.3/gcc/c-gimplify.c')
| -rw-r--r-- | gcc-4.2.1-5666.3/gcc/c-gimplify.c | 226 |
1 files changed, 226 insertions, 0 deletions
diff --git a/gcc-4.2.1-5666.3/gcc/c-gimplify.c b/gcc-4.2.1-5666.3/gcc/c-gimplify.c new file mode 100644 index 000000000..7ddc88cf4 --- /dev/null +++ b/gcc-4.2.1-5666.3/gcc/c-gimplify.c @@ -0,0 +1,226 @@ +/* Tree lowering pass. This pass gimplifies the tree representation built + by the C-based front ends. The structure of gimplified, or + language-independent, trees is dictated by the grammar described in this + file. + Copyright (C) 2002, 2003, 2004, 2005 Free Software Foundation, Inc. + Lowering of expressions contributed by Sebastian Pop <s.pop@laposte.net> + Re-written to support lowering of whole function trees, documentation + and miscellaneous cleanups by Diego Novillo <dnovillo@redhat.com> + +This file is part of GCC. + +GCC is free software; you can redistribute it and/or modify it under +the terms of the GNU General Public License as published by the Free +Software Foundation; either version 2, or (at your option) any later +version. + +GCC is distributed in the hope that it will be useful, but WITHOUT ANY +WARRANTY; without even the implied warranty of MERCHANTABILITY or +FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License +for more details. + +You should have received a copy of the GNU General Public License +along with GCC; see the file COPYING. If not, write to the Free +Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA +02110-1301, USA. */ + +#include "config.h" +#include "system.h" +#include "coretypes.h" +#include "tm.h" +#include "tree.h" +#include "varray.h" +#include "c-tree.h" +#include "c-common.h" +#include "tree-gimple.h" +#include "hard-reg-set.h" +#include "basic-block.h" +#include "tree-flow.h" +#include "tree-inline.h" +#include "diagnostic.h" +#include "langhooks.h" +#include "langhooks-def.h" +#include "flags.h" +#include "rtl.h" +#include "toplev.h" +#include "tree-dump.h" +#include "c-pretty-print.h" +#include "cgraph.h" + + +/* The gimplification pass converts the language-dependent trees + (ld-trees) emitted by the parser into language-independent trees + (li-trees) that are the target of SSA analysis and transformations. + + Language-independent trees are based on the SIMPLE intermediate + representation used in the McCAT compiler framework: + + "Designing the McCAT Compiler Based on a Family of Structured + Intermediate Representations," + L. Hendren, C. Donawa, M. Emami, G. Gao, Justiani, and B. Sridharan, + Proceedings of the 5th International Workshop on Languages and + Compilers for Parallel Computing, no. 757 in Lecture Notes in + Computer Science, New Haven, Connecticut, pp. 406-420, + Springer-Verlag, August 3-5, 1992. + + http://www-acaps.cs.mcgill.ca/info/McCAT/McCAT.html + + Basically, we walk down gimplifying the nodes that we encounter. As we + walk back up, we check that they fit our constraints, and copy them + into temporaries if not. */ + +/* Gimplification of statement trees. */ + +/* Convert the tree representation of FNDECL from C frontend trees to + GENERIC. */ + +void +c_genericize (tree fndecl) +{ + FILE *dump_orig; + int local_dump_flags; + struct cgraph_node *cgn; + + /* Dump the C-specific tree IR. */ + dump_orig = dump_begin (TDI_original, &local_dump_flags); + if (dump_orig) + { + fprintf (dump_orig, "\n;; Function %s", + lang_hooks.decl_printable_name (fndecl, 2)); + fprintf (dump_orig, " (%s)\n", + IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (fndecl))); + fprintf (dump_orig, ";; enabled by -%s\n", dump_flag_name (TDI_original)); + fprintf (dump_orig, "\n"); + + if (local_dump_flags & TDF_RAW) + dump_node (DECL_SAVED_TREE (fndecl), + TDF_SLIM | local_dump_flags, dump_orig); + else + print_c_tree (dump_orig, DECL_SAVED_TREE (fndecl)); + fprintf (dump_orig, "\n"); + + dump_end (TDI_original, dump_orig); + } + + /* Go ahead and gimplify for now. */ + gimplify_function_tree (fndecl); + + /* Dump the genericized tree IR. */ + dump_function (TDI_generic, fndecl); + + /* Genericize all nested functions now. We do things in this order so + that items like VLA sizes are expanded properly in the context of + the correct function. */ + cgn = cgraph_node (fndecl); + for (cgn = cgn->nested; cgn ; cgn = cgn->next_nested) + c_genericize (cgn->decl); +} + +static void +add_block_to_enclosing (tree block) +{ + tree enclosing; + + for (enclosing = gimple_current_bind_expr (); + enclosing; enclosing = TREE_CHAIN (enclosing)) + if (BIND_EXPR_BLOCK (enclosing)) + break; + + enclosing = BIND_EXPR_BLOCK (enclosing); + BLOCK_SUBBLOCKS (enclosing) = chainon (BLOCK_SUBBLOCKS (enclosing), block); +} + +/* Genericize a scope by creating a new BIND_EXPR. + BLOCK is either a BLOCK representing the scope or a chain of _DECLs. + In the latter case, we need to create a new BLOCK and add it to the + BLOCK_SUBBLOCKS of the enclosing block. + BODY is a chain of C _STMT nodes for the contents of the scope, to be + genericized. */ + +tree +c_build_bind_expr (tree block, tree body) +{ + tree decls, bind; + + if (block == NULL_TREE) + decls = NULL_TREE; + else if (TREE_CODE (block) == BLOCK) + decls = BLOCK_VARS (block); + else + { + decls = block; + if (DECL_ARTIFICIAL (decls)) + block = NULL_TREE; + else + { + block = make_node (BLOCK); + BLOCK_VARS (block) = decls; + add_block_to_enclosing (block); + } + } + + if (!body) + body = build_empty_stmt (); + if (decls || block) + { + bind = build3 (BIND_EXPR, void_type_node, decls, body, block); + TREE_SIDE_EFFECTS (bind) = 1; + } + else + bind = body; + + return bind; +} + +/* Gimplification of expression trees. */ + +/* Gimplify a C99 compound literal expression. This just means adding + the DECL_EXPR before the current statement and using its anonymous + decl instead. */ + +static enum gimplify_status +gimplify_compound_literal_expr (tree *expr_p, tree *pre_p) +{ + tree decl_s = COMPOUND_LITERAL_EXPR_DECL_STMT (*expr_p); + tree decl = DECL_EXPR_DECL (decl_s); + + /* This decl isn't mentioned in the enclosing block, so add it to the + list of temps. FIXME it seems a bit of a kludge to say that + anonymous artificial vars aren't pushed, but everything else is. */ + if (DECL_NAME (decl) == NULL_TREE && !DECL_SEEN_IN_BIND_EXPR_P (decl)) + gimple_add_tmp_var (decl); + + gimplify_and_add (decl_s, pre_p); + *expr_p = decl; + return GS_OK; +} + +/* Do C-specific gimplification. Args are as for gimplify_expr. */ + +int +c_gimplify_expr (tree *expr_p, tree *pre_p, tree *post_p ATTRIBUTE_UNUSED) +{ + enum tree_code code = TREE_CODE (*expr_p); + + switch (code) + { + case DECL_EXPR: + /* This is handled mostly by gimplify.c, but we have to deal with + not warning about int x = x; as it is a GCC extension to turn off + this warning but only if warn_init_self is zero. */ + if (TREE_CODE (DECL_EXPR_DECL (*expr_p)) == VAR_DECL + && !DECL_EXTERNAL (DECL_EXPR_DECL (*expr_p)) + && !TREE_STATIC (DECL_EXPR_DECL (*expr_p)) + && (DECL_INITIAL (DECL_EXPR_DECL (*expr_p)) + == DECL_EXPR_DECL (*expr_p)) + && !warn_init_self) + TREE_NO_WARNING (DECL_EXPR_DECL (*expr_p)) = 1; + return GS_UNHANDLED; + + case COMPOUND_LITERAL_EXPR: + return gimplify_compound_literal_expr (expr_p, pre_p); + + default: + return GS_UNHANDLED; + } +} |