From eea05d39c799880df753e9b74d2d96e86215c46e Mon Sep 17 00:00:00 2001 From: Eric Botcazou Date: Sun, 20 Apr 2008 17:53:58 +0000 Subject: [PATCH] tree-sra.c (sra_walk_expr): Disable scalarization if on the LHS and not a full access. * tree-sra.c (sra_walk_expr) : Disable scalarization if on the LHS and not a full access. From-SVN: r134487 --- gcc/ChangeLog | 9 +++++++-- gcc/tree-sra.c | 20 +++++++++++++++----- 2 files changed, 22 insertions(+), 7 deletions(-) diff --git a/gcc/ChangeLog b/gcc/ChangeLog index d96a8e621c1..a760e7ff4d5 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,9 +1,14 @@ +2008-04-20 Eric Botcazou + + * tree-sra.c (sra_walk_expr) : Disable + scalarization if on the LHS and not a full access. + 2008-04-20 Ralf Wildenhues - * Makefile.in (s-gtyp-input): Remove tmp-gi.list before writing - it. + * Makefile.in (s-gtyp-input): Remove tmp-gi.list before writing it. 2008-04-18 Rafael Espindola + * tree-vrp.c (find_case_label_index): Fix the binary search. (find_case_label_range): New. (vrp_visit_switch_stmt): Use find_case_label_range. diff --git a/gcc/tree-sra.c b/gcc/tree-sra.c index 752f87da947..78a100f38d7 100644 --- a/gcc/tree-sra.c +++ b/gcc/tree-sra.c @@ -855,18 +855,28 @@ sra_walk_expr (tree *expr_p, block_stmt_iterator *bsi, bool is_output, if (elt) elt->is_vector_lhs = true; } + /* A bit field reference (access to *multiple* fields simultaneously) - is not currently scalarized. Consider this an access to the - complete outer element, to which walk_tree will bring us next. */ - + is not currently scalarized. Consider this an access to the full + outer element, to which walk_tree will bring us next. */ goto use_all; - case VIEW_CONVERT_EXPR: case NOP_EXPR: - /* Similarly, a view/nop explicitly wants to look at an object in a + /* Similarly, a nop explicitly wants to look at an object in a type other than the one we've scalarized. */ goto use_all; + case VIEW_CONVERT_EXPR: + /* Likewise for a view conversion, but with an additional twist: + it can be on the LHS and, in this case, an access to the full + outer element would mean a killing def. So we need to punt + if we haven't already a full access to the current element, + because we cannot pretend to have a killing def if we only + have a partial access at some level. */ + if (is_output && !use_all_p && inner != expr) + disable_scalarization = true; + goto use_all; + case WITH_SIZE_EXPR: /* This is a transparent wrapper. The entire inner expression really is being used. */ -- 2.30.2