diff options
Diffstat (limited to 'gcc/gimplify.c')
| -rw-r--r-- | gcc/gimplify.c | 106 |
1 files changed, 104 insertions, 2 deletions
diff --git a/gcc/gimplify.c b/gcc/gimplify.c index 842ef378a9d..bd82051d158 100644 --- a/gcc/gimplify.c +++ b/gcc/gimplify.c @@ -3456,6 +3456,83 @@ rhs_predicate_for (tree lhs) return is_gimple_mem_or_call_rhs; } +/* 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, gimple_seq *pre_p) +{ + tree decl_s = COMPOUND_LITERAL_EXPR_DECL_EXPR (*expr_p); + tree decl = DECL_EXPR_DECL (decl_s); + /* Mark the decl as addressable if the compound literal + expression is addressable now, otherwise it is marked too late + after we gimplify the initialization expression. */ + if (TREE_ADDRESSABLE (*expr_p)) + TREE_ADDRESSABLE (decl) = 1; + + /* Preliminarily mark non-addressed complex variables as eligible + for promotion to gimple registers. We'll transform their uses + as we find them. */ + if ((TREE_CODE (TREE_TYPE (decl)) == COMPLEX_TYPE + || TREE_CODE (TREE_TYPE (decl)) == VECTOR_TYPE) + && !TREE_THIS_VOLATILE (decl) + && !needs_to_live_in_memory (decl)) + DECL_GIMPLE_REG_P (decl) = 1; + + /* 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; +} + +/* Optimize embedded COMPOUND_LITERAL_EXPRs within a CONSTRUCTOR, + return a new CONSTRUCTOR if something changed. */ + +static tree +optimize_compound_literals_in_ctor (tree orig_ctor) +{ + tree ctor = orig_ctor; + VEC(constructor_elt,gc) *elts = CONSTRUCTOR_ELTS (ctor); + unsigned int idx, num = VEC_length (constructor_elt, elts); + + for (idx = 0; idx < num; idx++) + { + tree value = VEC_index (constructor_elt, elts, idx)->value; + tree newval = value; + if (TREE_CODE (value) == CONSTRUCTOR) + newval = optimize_compound_literals_in_ctor (value); + else if (TREE_CODE (value) == COMPOUND_LITERAL_EXPR) + { + tree decl_s = COMPOUND_LITERAL_EXPR_DECL_EXPR (value); + tree decl = DECL_EXPR_DECL (decl_s); + tree init = DECL_INITIAL (decl); + + if (!TREE_ADDRESSABLE (value) + && !TREE_ADDRESSABLE (decl) + && init) + newval = optimize_compound_literals_in_ctor (init); + } + if (newval == value) + continue; + + if (ctor == orig_ctor) + { + ctor = copy_node (orig_ctor); + CONSTRUCTOR_ELTS (ctor) = VEC_copy (constructor_elt, gc, elts); + elts = CONSTRUCTOR_ELTS (ctor); + } + VEC_index (constructor_elt, elts, idx)->value = newval; + } + return ctor; +} + + /* A subroutine of gimplify_modify_expr. Break out elements of a CONSTRUCTOR used as an initializer into separate MODIFY_EXPRs. @@ -3474,7 +3551,7 @@ static enum gimplify_status gimplify_init_constructor (tree *expr_p, gimple_seq *pre_p, gimple_seq *post_p, bool want_value, bool notify_temp_creation) { - tree object; + tree object, new_ctor; tree ctor = TREE_OPERAND (*expr_p, 1); tree type = TREE_TYPE (ctor); enum gimplify_status ret; @@ -3492,7 +3569,8 @@ gimplify_init_constructor (tree *expr_p, gimple_seq *pre_p, gimple_seq *post_p, } object = TREE_OPERAND (*expr_p, 0); - elts = CONSTRUCTOR_ELTS (ctor); + new_ctor = optimize_compound_literals_in_ctor (ctor); + elts = CONSTRUCTOR_ELTS (new_ctor); ret = GS_ALL_DONE; switch (TREE_CODE (type)) @@ -4099,6 +4177,26 @@ gimplify_modify_expr_rhs (tree *expr_p, tree *from_p, tree *to_p, return GS_OK; } + case COMPOUND_LITERAL_EXPR: + { + tree complit = TREE_OPERAND (*expr_p, 1); + tree decl_s = COMPOUND_LITERAL_EXPR_DECL_EXPR (complit); + tree decl = DECL_EXPR_DECL (decl_s); + tree init = DECL_INITIAL (decl); + + /* struct T x = (struct T) { 0, 1, 2 } can be optimized + into struct T x = { 0, 1, 2 } if the address of the + compound literal has never been taken. */ + if (!TREE_ADDRESSABLE (complit) + && !TREE_ADDRESSABLE (decl) + && init) + { + *expr_p = copy_node (*expr_p); + TREE_OPERAND (*expr_p, 1) = init; + return GS_OK; + } + } + default: ret = GS_UNHANDLED; break; @@ -6361,6 +6459,10 @@ gimplify_expr (tree *expr_p, gimple_seq *pre_p, gimple_seq *post_p, ret = gimplify_compound_expr (expr_p, pre_p, fallback != fb_none); break; + case COMPOUND_LITERAL_EXPR: + ret = gimplify_compound_literal_expr (expr_p, pre_p); + break; + case MODIFY_EXPR: case INIT_EXPR: ret = gimplify_modify_expr (expr_p, pre_p, post_p, |
