From 48cc8d3b41eaf47e1a8f3eaa4c4f76c655ae4784 Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Wed, 26 Jan 2005 16:07:41 -0800 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. From-SVN: r94294 --- 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 288527460ae..3f158552670 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,11 @@ +2005-01-26 Richard Henderson + + 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 * c-decl.c, expmed.c, expr.c: Revert last change. diff --git a/gcc/c-decl.c b/gcc/c-decl.c index 6673927eab6..61521e861c7 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 ed693a3166f..1f82b1d9834 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 -- 2.30.2