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author | Richard Kenner <kenner@vlsi1.ultra.nyu.edu> | 2001-11-27 14:31:29 +0000 |
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committer | Richard Kenner <kenner@gcc.gnu.org> | 2001-11-27 09:31:29 -0500 |
commit | ac79cd5ab9b4c4c32725845ef3a2c91e29e67f7e (patch) | |
tree | df8e146fbd8a8ed512495c0e24ff0baaa409303d /gcc/tree.c | |
parent | 188235dff14c855c929b8a52378deaf452637e1a (diff) | |
download | gcc-ac79cd5ab9b4c4c32725845ef3a2c91e29e67f7e.zip gcc-ac79cd5ab9b4c4c32725845ef3a2c91e29e67f7e.tar.gz gcc-ac79cd5ab9b4c4c32725845ef3a2c91e29e67f7e.tar.bz2 |
Makefile.in (c-lang.o): Depends on langhooks-def.h.
* Makefile.in (c-lang.o): Depends on langhooks-def.h.
(expr.o, varasm.o): Depends on langhooks.h.
* c-common.c (c_safe_from_p): Always declare.
(c_expand_expr): Refine when declared.
* c-lang.c (c-common.h): Now include.
(LANG_HOOKS_SAFE_FROM_P): Define new hook.
(c_init): Don't set lang_safe_from_expr.
* expr.c (langhooks.h): Now include.
(lang_safe_from_p): No longer define.
(safe_from_p): Use lang hook.
(expand_expr): Set IGNORE if VOID_TYPE result of VIEW_CONVERT_EXPR too.
(expand_expr, case VIEW_CONVERT_EXPR): Pass ro_modifier down.
* expr.h (lang_expand_constant, lang_safe_from_p): Delete.
* langhooks-def.h (lhd_return_tree, lhd_safe_from_p): New decls.
(LANG_HOOKS_EXPAND_CONSTANT, LANG_HOOKS_SAFE_FROM_P): New hooks.
* langhooks.c (lhd_return_tree, lhd_safe_from_p): New functions.
* langhooks.h (struct lang_hooks): New fields expand_constant
and safe_from_p.
* output.h (output_constant): Size arg is HOST_WIDE_INT.
* stmt.c (expand_decl_init): No longer need to expand constant
for CONST_DECL.
* stor-layout.c (put_pending_size): Don't check for SAVE_EXPR.
* toplev.c (lang_expand_constant): Delete var.
* tree.c (save_expr): Don't put another SAVE_EXPR around simple
operations on SAVE_EXPR.
* varasm.c (langhooks.h): Now include.
(compare_constant_1): Use lang_hooks, not lang_expand_constant.
(record_constant_1, output_addressed_constants): Likewise.
(initializer_constant_valid_p, output_constant): Likewise.
(output_constant_def): Process no-defer of string constant.
(output_addressed_constants, case ADDR_EXPR): Use handled_component_p.
(output_constant): Strip more conversions.
Track our size and pad for the rest.
(array_size_for_constructor): Remove code for non-byte STRING_CST.
(output_constructor): SIZE now HOST_WIDE_INT.
* cp/Make-lang.in (cp-lang.o): Depends on c-common.h.
* cp/cp-lang.c (c-common.h): Include.
(LANG_HOOKS_EXPAND_CONSTANT, LANG_HOOKS_SAFE_FROM_P): New hooks.
* cp/decl.c (cxx_init_decl_processing): Don't set lang_safe_from_p.
* cp/expr.c (init_cplus_expand): Don't set lang_expand_constant.
From-SVN: r47376
Diffstat (limited to 'gcc/tree.c')
-rw-r--r-- | gcc/tree.c | 19 |
1 files changed, 16 insertions, 3 deletions
@@ -1549,20 +1549,33 @@ save_expr (expr) tree expr; { tree t = fold (expr); + tree inner; /* We don't care about whether this can be used as an lvalue in this context. */ while (TREE_CODE (t) == NON_LVALUE_EXPR) t = TREE_OPERAND (t, 0); + + /* If we have simple operations applied to a SAVE_EXPR or to a SAVE_EXPR and + a constant, it will be more efficient to not make another SAVE_EXPR since + it will allow better simplification and GCSE will be able to merge the + computations if they actualy occur. */ + for (inner = t; + (TREE_CODE_CLASS (TREE_CODE (inner)) == '1' + || (TREE_CODE_CLASS (TREE_CODE (inner)) == '2' + && TREE_CONSTANT (TREE_OPERAND (inner, 1)))); + inner = TREE_OPERAND (inner, 0)) + ; + /* If the tree evaluates to a constant, then we don't want to hide that fact (i.e. this allows further folding, and direct checks for constants). However, a read-only object that has side effects cannot be bypassed. Since it is no problem to reevaluate literals, we just return the literal node. */ - - if (TREE_CONSTANT (t) || (TREE_READONLY (t) && ! TREE_SIDE_EFFECTS (t)) - || TREE_CODE (t) == SAVE_EXPR || TREE_CODE (t) == ERROR_MARK) + if (TREE_CONSTANT (inner) + || (TREE_READONLY (inner) && ! TREE_SIDE_EFFECTS (inner)) + || TREE_CODE (inner) == SAVE_EXPR || TREE_CODE (inner) == ERROR_MARK) return t; /* If T contains a PLACEHOLDER_EXPR, we must evaluate it each time, since |