diff options
Diffstat (limited to 'gcc/gimple-fold.c')
| -rw-r--r-- | gcc/gimple-fold.c | 74 |
1 files changed, 68 insertions, 6 deletions
diff --git a/gcc/gimple-fold.c b/gcc/gimple-fold.c index ab74494..3148c6b 100644 --- a/gcc/gimple-fold.c +++ b/gcc/gimple-fold.c @@ -3958,6 +3958,10 @@ static const size_t clear_padding_buf_size = 32 * clear_padding_unit; /* Data passed through __builtin_clear_padding folding. */ struct clear_padding_struct { location_t loc; + /* 0 during __builtin_clear_padding folding, nonzero during + clear_type_padding_in_mask. In that case, instead of clearing the + non-padding bits in union_ptr array clear the padding bits in there. */ + bool clear_in_mask; tree base; tree alias_type; gimple_stmt_iterator *gsi; @@ -4000,6 +4004,39 @@ clear_padding_flush (clear_padding_struct *buf, bool full) size_t padding_bytes = buf->padding_bytes; if (buf->union_ptr) { + if (buf->clear_in_mask) + { + /* During clear_type_padding_in_mask, clear the padding + bits set in buf->buf in the buf->union_ptr mask. */ + for (size_t i = 0; i < end; i++) + { + if (buf->buf[i] == (unsigned char) ~0) + padding_bytes++; + else + { + memset (&buf->union_ptr[buf->off + i - padding_bytes], + 0, padding_bytes); + padding_bytes = 0; + buf->union_ptr[buf->off + i] &= ~buf->buf[i]; + } + } + if (full) + { + memset (&buf->union_ptr[buf->off + end - padding_bytes], + 0, padding_bytes); + buf->off = 0; + buf->size = 0; + buf->padding_bytes = 0; + } + else + { + memmove (buf->buf, buf->buf + end, buf->size - end); + buf->off += end; + buf->size -= end; + buf->padding_bytes = padding_bytes; + } + return; + } /* Inside of a union, instead of emitting any code, instead clear all bits in the union_ptr buffer that are clear in buf. Whole padding bytes don't clear anything. */ @@ -4311,6 +4348,7 @@ clear_padding_union (clear_padding_struct *buf, tree type, HOST_WIDE_INT sz) clear_padding_flush (buf, false); union_buf = XALLOCA (clear_padding_struct); union_buf->loc = buf->loc; + union_buf->clear_in_mask = buf->clear_in_mask; union_buf->base = NULL_TREE; union_buf->alias_type = NULL_TREE; union_buf->gsi = NULL; @@ -4335,9 +4373,10 @@ clear_padding_union (clear_padding_struct *buf, tree type, HOST_WIDE_INT sz) continue; gcc_assert (TREE_CODE (TREE_TYPE (field)) == ARRAY_TYPE && !COMPLETE_TYPE_P (TREE_TYPE (field))); - error_at (buf->loc, "flexible array member %qD does not have " - "well defined padding bits for %qs", - field, "__builtin_clear_padding"); + if (!buf->clear_in_mask) + error_at (buf->loc, "flexible array member %qD does not have " + "well defined padding bits for %qs", + field, "__builtin_clear_padding"); continue; } HOST_WIDE_INT fldsz = tree_to_shwi (DECL_SIZE_UNIT (field)); @@ -4529,9 +4568,10 @@ clear_padding_type (clear_padding_struct *buf, tree type, HOST_WIDE_INT sz) continue; gcc_assert (TREE_CODE (ftype) == ARRAY_TYPE && !COMPLETE_TYPE_P (ftype)); - error_at (buf->loc, "flexible array member %qD does not have " - "well defined padding bits for %qs", - field, "__builtin_clear_padding"); + if (!buf->clear_in_mask) + error_at (buf->loc, "flexible array member %qD does not " + "have well defined padding bits for %qs", + field, "__builtin_clear_padding"); } else if (is_empty_type (TREE_TYPE (field))) continue; @@ -4645,6 +4685,27 @@ clear_padding_type (clear_padding_struct *buf, tree type, HOST_WIDE_INT sz) } } +/* Clear padding bits of TYPE in MASK. */ + +void +clear_type_padding_in_mask (tree type, unsigned char *mask) +{ + clear_padding_struct buf; + buf.loc = UNKNOWN_LOCATION; + buf.clear_in_mask = true; + buf.base = NULL_TREE; + buf.alias_type = NULL_TREE; + buf.gsi = NULL; + buf.align = 0; + buf.off = 0; + buf.padding_bytes = 0; + buf.sz = int_size_in_bytes (type); + buf.size = 0; + buf.union_ptr = mask; + clear_padding_type (&buf, type, buf.sz); + clear_padding_flush (&buf, true); +} + /* Fold __builtin_clear_padding builtin. */ static bool @@ -4664,6 +4725,7 @@ gimple_fold_builtin_clear_padding (gimple_stmt_iterator *gsi) gsi_prev (&gsiprev); buf.loc = loc; + buf.clear_in_mask = false; buf.base = ptr; buf.alias_type = NULL_TREE; buf.gsi = gsi; |