diff options
| author | Eric Botcazou <ebotcazou@adacore.com> | 2018-06-03 11:51:10 +0000 |
|---|---|---|
| committer | Eric Botcazou <ebotcazou@gcc.gnu.org> | 2018-06-03 11:51:10 +0000 |
| commit | c14add82fa4ec24a09e48d56094d9f46310f0809 (patch) | |
| tree | 74d872b2a20990ecc63ce48b040263450fdce3df /gcc/gimple-ssa-store-merging.c | |
| parent | 5b9a3332c27e2f4ea372f2fc53bcbd27e204fb73 (diff) | |
re PR tree-optimization/86034 (wrong code for bit-field manipulation at -Os)
PR tree-optimization/86034
* gimple-ssa-store-merging.c (output_merged_store): Convert the RHS to
the unsigned bitfield type in a bit insertion sequence if it does not
have a larger precision than the bitfield size.
(process_store): Also bypass widening conversions for BIT_INSERT_EXPR.
From-SVN: r261128
Diffstat (limited to 'gcc/gimple-ssa-store-merging.c')
| -rw-r--r-- | gcc/gimple-ssa-store-merging.c | 14 |
1 files changed, 10 insertions, 4 deletions
diff --git a/gcc/gimple-ssa-store-merging.c b/gcc/gimple-ssa-store-merging.c index 3c63e75fcf6..b972f9bef84 100644 --- a/gcc/gimple-ssa-store-merging.c +++ b/gcc/gimple-ssa-store-merging.c @@ -3778,7 +3778,14 @@ imm_store_chain_info::output_merged_store (merged_store_group *group) const HOST_WIDE_INT end_gap = (try_bitpos + try_size) - (info->bitpos + info->bitsize); tree tem = info->ops[0].val; - if ((BYTES_BIG_ENDIAN ? start_gap : end_gap) > 0) + if (TYPE_PRECISION (TREE_TYPE (tem)) <= info->bitsize) + { + tree bitfield_type + = build_nonstandard_integer_type (info->bitsize, + UNSIGNED); + tem = gimple_convert (&seq, loc, bitfield_type, tem); + } + else if ((BYTES_BIG_ENDIAN ? start_gap : end_gap) > 0) { const unsigned HOST_WIDE_INT imask = (HOST_WIDE_INT_1U << info->bitsize) - 1; @@ -4270,13 +4277,12 @@ pass_store_merging::process_store (gimple *stmt) || !multiple_p (bitpos, BITS_PER_UNIT)) && const_bitsize <= 64) { - /* Bypass a truncating conversion to the bit-field type. */ + /* Bypass a conversion to the bit-field type. */ if (is_gimple_assign (def_stmt) && CONVERT_EXPR_CODE_P (rhs_code)) { tree rhs1 = gimple_assign_rhs1 (def_stmt); if (TREE_CODE (rhs1) == SSA_NAME - && INTEGRAL_TYPE_P (TREE_TYPE (rhs1)) - && const_bitsize <= TYPE_PRECISION (TREE_TYPE (rhs1))) + && INTEGRAL_TYPE_P (TREE_TYPE (rhs1))) rhs = rhs1; } rhs_code = BIT_INSERT_EXPR; |