From 24bdc38750492797be9be517aa0d2edadee7cc3b Mon Sep 17 00:00:00 2001
From: rth <rth@138bc75d-0d04-0410-961f-82ee72b054a4>
Date: Thu, 27 Jan 2005 00:07:41 +0000
Subject: [PATCH] For real this time...
PR middle-end/18008
* c-decl.c (finish_struct): Set DECL_MODE after resetting a
field's type.
* expr.c (store_field): Strip conversions to odd-bit-sized types
if the destination field width matches.
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@94294 138bc75d-0d04-0410-961f-82ee72b054a4
---
gcc/ChangeLog | 8 ++++++++
gcc/c-decl.c | 7 +++++--
gcc/expr.c | 16 +++++++++++++++-
3 files changed, 28 insertions(+), 3 deletions(-)
diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 288527460ae8..3f158552670e 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,11 @@
+2005-01-26 Richard Henderson <rth@redhat.com>
+
+ PR middle-end/18008
+ * c-decl.c (finish_struct): Set DECL_MODE after resetting a
+ field's type.
+ * expr.c (store_field): Strip conversions to odd-bit-sized types
+ if the destination field width matches.
+
2005-01-26 Richard Henderson <rth@redhat.com>
* c-decl.c, expmed.c, expr.c: Revert last change.
diff --git a/gcc/c-decl.c b/gcc/c-decl.c
index 6673927eab60..61521e861c7b 100644
--- a/gcc/c-decl.c
+++ b/gcc/c-decl.c
@@ -5301,8 +5301,11 @@ finish_struct (tree t, tree fieldlist, tree attributes)
= tree_low_cst (DECL_INITIAL (*fieldlistp), 1);
tree type = TREE_TYPE (*fieldlistp);
if (width != TYPE_PRECISION (type))
- TREE_TYPE (*fieldlistp)
- = build_nonstandard_integer_type (width, TYPE_UNSIGNED (type));
+ {
+ TREE_TYPE (*fieldlistp)
+ = build_nonstandard_integer_type (width, TYPE_UNSIGNED (type));
+ DECL_MODE (*fieldlistp) = TYPE_MODE (TREE_TYPE (*fieldlistp));
+ }
DECL_INITIAL (*fieldlistp) = 0;
}
else
diff --git a/gcc/expr.c b/gcc/expr.c
index ed693a3166f6..1f82b1d98346 100644
--- a/gcc/expr.c
+++ b/gcc/expr.c
@@ -5215,7 +5215,21 @@ store_field (rtx target, HOST_WIDE_INT bitsize, HOST_WIDE_INT bitpos,
&& TREE_CODE (TYPE_SIZE (TREE_TYPE (exp))) == INTEGER_CST
&& compare_tree_int (TYPE_SIZE (TREE_TYPE (exp)), bitsize) != 0))
{
- rtx temp = expand_expr (exp, NULL_RTX, VOIDmode, 0);
+ rtx temp;
+
+ /* If EXP is a NOP_EXPR of precision less than its mode, then that
+ implies a mask operation. If the precision is the same size as
+ the field we're storing into, that mask is redundant. This is
+ particularly common with bit field assignments generated by the
+ C front end. */
+ if (TREE_CODE (exp) == NOP_EXPR
+ && INTEGRAL_TYPE_P (TREE_TYPE (exp))
+ && (TYPE_PRECISION (TREE_TYPE (exp))
+ < GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (exp))))
+ && bitsize == TYPE_PRECISION (TREE_TYPE (exp)))
+ exp = TREE_OPERAND (exp, 0);
+
+ temp = expand_expr (exp, NULL_RTX, VOIDmode, 0);
/* If BITSIZE is narrower than the size of the type of EXP
we will be narrowing TEMP. Normally, what's wanted are the
--
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