From ee40d8d45213caf0cfb63e603f0fd5a58532e751 Mon Sep 17 00:00:00 2001 From: Yao Qi Date: Mon, 28 Nov 2016 17:09:26 +0000 Subject: [PATCH] Move computed value's frame id to piece_closure Nowadays, we set computed value's frame id, which is a misuse to me. The computed value itself doesn't care about frame id, but function value_computed_funcs (val)->read (or read_pieced_value) cares about which frame the register is relative to, so 'struct piece_closure' is a better place to fit frame id. This patch adds a frame id in 'struct piece_closure', and use it instead of using computed value's frame id. gdb: 2016-11-28 Yao Qi * dwarf2loc.c (struct piece_closure) : New field. (allocate_piece_closure): Add new parameter 'frame' and set closure's frame_id field accordingly. (read_pieced_value): Get frame from closure instead of value. (dwarf2_evaluate_loc_desc_full): Remove code getting frame id. Don't set value's frame id. --- gdb/dwarf2loc.c | 24 +++++++++++------------- 1 file changed, 11 insertions(+), 13 deletions(-) diff --git a/gdb/dwarf2loc.c b/gdb/dwarf2loc.c index 128f654..aaf88e4 100644 --- a/gdb/dwarf2loc.c +++ b/gdb/dwarf2loc.c @@ -1465,6 +1465,10 @@ struct piece_closure /* The pieces themselves. */ struct dwarf_expr_piece *pieces; + + /* Frame ID of frame to which a register value is relative, used + only by DWARF_VALUE_REGISTER. */ + struct frame_id frame_id; }; /* Allocate a closure for a value formed from separately-described @@ -1473,7 +1477,7 @@ struct piece_closure static struct piece_closure * allocate_piece_closure (struct dwarf2_per_cu_data *per_cu, int n_pieces, struct dwarf_expr_piece *pieces, - int addr_size) + int addr_size, struct frame_info *frame) { struct piece_closure *c = XCNEW (struct piece_closure); int i; @@ -1483,6 +1487,10 @@ allocate_piece_closure (struct dwarf2_per_cu_data *per_cu, c->n_pieces = n_pieces; c->addr_size = addr_size; c->pieces = XCNEWVEC (struct dwarf_expr_piece, n_pieces); + if (frame == NULL) + c->frame_id = null_frame_id; + else + c->frame_id = get_frame_id (frame); memcpy (c->pieces, pieces, n_pieces * sizeof (struct dwarf_expr_piece)); for (i = 0; i < n_pieces; ++i) @@ -1731,18 +1739,12 @@ read_pieced_value (struct value *v) gdb_byte *contents; struct piece_closure *c = (struct piece_closure *) value_computed_closure (v); - struct frame_info *frame; size_t type_len; size_t buffer_size = 0; std::vector buffer; int bits_big_endian = gdbarch_bits_big_endian (get_type_arch (value_type (v))); - /* VALUE_FRAME_ID is used instead of VALUE_NEXT_FRAME_ID here - because FRAME is passed to get_frame_register_bytes(), which - does its own "->next" operation. */ - frame = frame_find_by_id (VALUE_FRAME_ID (v)); - if (value_type (v) != value_enclosing_type (v)) internal_error (__FILE__, __LINE__, _("Should not be able to create a lazy value with " @@ -1802,6 +1804,7 @@ read_pieced_value (struct value *v) { case DWARF_VALUE_REGISTER: { + struct frame_info *frame = frame_find_by_id (c->frame_id); struct gdbarch *arch = get_frame_arch (frame); int gdb_regnum = dwarf_reg_to_regnum_or_error (arch, p->v.regno); int optim, unavail; @@ -2370,10 +2373,6 @@ dwarf2_evaluate_loc_desc_full (struct type *type, struct frame_info *frame, if (ctx.num_pieces > 0) { struct piece_closure *c; - struct frame_id frame_id - = frame == NULL - ? null_frame_id - : get_frame_id (get_next_frame_sentinel_okay (frame)); ULONGEST bit_size = 0; int i; @@ -2383,12 +2382,11 @@ dwarf2_evaluate_loc_desc_full (struct type *type, struct frame_info *frame, invalid_synthetic_pointer (); c = allocate_piece_closure (per_cu, ctx.num_pieces, ctx.pieces, - ctx.addr_size); + ctx.addr_size, frame); /* We must clean up the value chain after creating the piece closure but before allocating the result. */ do_cleanups (value_chain); retval = allocate_computed_value (type, &pieced_value_funcs, c); - VALUE_NEXT_FRAME_ID (retval) = frame_id; set_value_offset (retval, byte_offset); } else -- 2.7.4