[PATCH 09/43] Move push_dwarf_reg_entry_value to expr.c

Zoran Zaric via Gdb-patches
2021-03-01T14:46:58Z

From: Zoran Zaric <zoran.zaric@amd.com>

Following the idea of merging the evaluators, the
push_dwarf_reg_entry_value method can be moved from
dwarf_expr_executor and dwarf_evaluate_loc_desc classes
to their base class dwarf_expr_context.

gdb/ChangeLog:

* dwarf2/expr.c
(dwarf_expr_context::push_dwarf_reg_entry_value): Move from
dwarf_evaluate_loc_desc.
* dwarf2/frame.c
(dwarf_expr_executor::push_dwarf_reg_entry_value): Remove
method.
* dwarf2/loc.c (dwarf_expr_reg_to_entry_parameter): Expose
function.
(dwarf_evaluate_loc_desc::push_dwarf_reg_entry_value): Move to
dwarf_expr_context.
* dwarf2/loc.h (dwarf_expr_reg_to_entry_parameter): Expose
function.
---
gdb/dwarf2/expr.c | 51 +++++++++++++++++++++++++++++++++
gdb/dwarf2/expr.h | 16 +++++------
gdb/dwarf2/frame.c | 7 -----
gdb/dwarf2/loc.c | 70 ++--------------------------------------------
gdb/dwarf2/loc.h | 14 ++++++++++
5 files changed, 75 insertions(+), 83 deletions(-)

diff --git a/gdb/dwarf2/expr.c b/gdb/dwarf2/expr.c
index 872de16cd70..0b7f3c90728 100644
--- a/gdb/dwarf2/expr.c
+++ b/gdb/dwarf2/expr.c
@@ -268,6 +268,57 @@ dwarf_expr_context::read_mem (gdb_byte *buf, CORE_ADDR addr,
read_memory (addr, buf, length);
}

+/* See expr.h. */
+
+void
+dwarf_expr_context::push_dwarf_reg_entry_value
+ (enum call_site_parameter_kind kind,
+ union call_site_parameter_u kind_u,
+ int deref_size)
+{
+ ensure_have_per_cu (per_cu, "DW_OP_entry_value");
+ ensure_have_frame (frame, "DW_OP_entry_value");
+
+ dwarf2_per_cu_data *caller_per_cu;
+ dwarf2_per_objfile *caller_per_objfile;
+ struct frame_info *caller_frame = get_prev_frame (frame);
+ struct call_site_parameter *parameter
+ = dwarf_expr_reg_to_entry_parameter (frame, kind, kind_u,
+ &caller_per_cu,
+ &caller_per_objfile);
+ const gdb_byte *data_src
+ = deref_size == -1 ? parameter->value : parameter->data_value;
+ size_t size
+ = deref_size == -1 ? parameter->value_size : parameter->data_value_size;
+
+ /* DEREF_SIZE size is not verified here. */
+ if (data_src == NULL)
+ throw_error (NO_ENTRY_VALUE_ERROR,
+ _("Cannot resolve DW_AT_call_data_value"));
+
+ /* We are about to evaluate an expression in the context of the caller
+ of the current frame. This evaluation context may be different from
+ the current (callee's) context), so temporarily set the caller's context.
+
+ It is possible for the caller to be from a different objfile from the
+ callee if the call is made through a function pointer. */
+ scoped_restore save_frame = make_scoped_restore (&this->frame,
+ caller_frame);
+ scoped_restore save_per_cu = make_scoped_restore (&this->per_cu,
+ caller_per_cu);
+ scoped_restore save_obj_addr = make_scoped_restore (&this->obj_address,
+ (CORE_ADDR) 0);
+ scoped_restore save_per_objfile = make_scoped_restore (&this->per_objfile,
+ caller_per_objfile);
+
+ scoped_restore save_arch = make_scoped_restore (&this->gdbarch);
+ this->gdbarch = this->per_objfile->objfile->arch ();
+ scoped_restore save_addr_size = make_scoped_restore (&this->addr_size);
+ this->addr_size = this->per_cu->addr_size ();
+
+ this->eval (data_src, size);
+}
+
/* Require that TYPE be an integral type; throw an exception if not. */

static void
diff --git a/gdb/dwarf2/expr.h b/gdb/dwarf2/expr.h
index 713bdd94f27..09fec0b871e 100644
--- a/gdb/dwarf2/expr.h
+++ b/gdb/dwarf2/expr.h
@@ -198,14 +198,6 @@ struct dwarf_expr_context
/* Read LENGTH bytes at ADDR into BUF. */
virtual void read_mem (gdb_byte *buf, CORE_ADDR addr, size_t length);

- /* Push on DWARF stack an entry evaluated for DW_TAG_call_site's
- parameter matching KIND and KIND_U at the caller of specified BATON.
- If DEREF_SIZE is not -1 then use DW_AT_call_data_value instead of
- DW_AT_call_value. */
- virtual void push_dwarf_reg_entry_value (enum call_site_parameter_kind kind,
- union call_site_parameter_u kind_u,
- int deref_size) = 0;
-
/* Return the `object address' for DW_OP_push_object_address. */
virtual CORE_ADDR get_object_address ()
{
@@ -245,6 +237,14 @@ struct dwarf_expr_context
STACK while it being passed to and returned from the called DWARF
subroutine. */
void dwarf_call (cu_offset die_cu_off);
+
+ /* Push on DWARF stack an entry evaluated for DW_TAG_call_site's
+ parameter matching KIND and KIND_U at the caller of specified BATON.
+ If DEREF_SIZE is not -1 then use DW_AT_call_data_value instead of
+ DW_AT_call_value. */
+ void push_dwarf_reg_entry_value (enum call_site_parameter_kind kind,
+ union call_site_parameter_u kind_u,
+ int deref_size);
};

/* Return the value of register number REG (a DWARF register number),
diff --git a/gdb/dwarf2/frame.c b/gdb/dwarf2/frame.c
index ce95a811abd..abbd24b8ed0 100644
--- a/gdb/dwarf2/frame.c
+++ b/gdb/dwarf2/frame.c
@@ -231,13 +231,6 @@ class dwarf_expr_executor : public dwarf_expr_context
: dwarf_expr_context (per_objfile)
{}

- void push_dwarf_reg_entry_value (enum call_site_parameter_kind kind,
- union call_site_parameter_u kind_u,
- int deref_size) override
- {
- invalid ("DW_OP_entry_value");
- }
-
private:

void invalid (const char *op) ATTRIBUTE_NORETURN
diff --git a/gdb/dwarf2/loc.c b/gdb/dwarf2/loc.c
index 9c4872436d7..1779241d9dc 100644
--- a/gdb/dwarf2/loc.c
+++ b/gdb/dwarf2/loc.c
@@ -52,13 +52,6 @@ static struct value *dwarf2_evaluate_loc_desc_full
size_t size, dwarf2_per_cu_data *per_cu, dwarf2_per_objfile *per_objfile,
struct type *subobj_type, LONGEST subobj_byte_offset);

-static struct call_site_parameter *dwarf_expr_reg_to_entry_parameter
- (struct frame_info *frame,
- enum call_site_parameter_kind kind,
- union call_site_parameter_u kind_u,
- dwarf2_per_cu_data **per_cu_return,
- dwarf2_per_objfile **per_objfile_return);
-
static struct value *indirect_synthetic_pointer
(sect_offset die, LONGEST byte_offset,
dwarf2_per_cu_data *per_cu,
@@ -631,61 +624,6 @@ class dwarf_evaluate_loc_desc : public dwarf_expr_context
dwarf_evaluate_loc_desc (dwarf2_per_objfile *per_objfile)
: dwarf_expr_context (per_objfile)
{}
-
- /* Execute DWARF block of call_site_parameter which matches KIND and
- KIND_U. Choose DEREF_SIZE value of that parameter. Search
- caller of this objects's frame.
-
- The caller can be from a different CU - per_cu_dwarf_call
- implementation can be more simple as it does not support cross-CU
- DWARF executions. */
-
- void push_dwarf_reg_entry_value (enum call_site_parameter_kind kind,
- union call_site_parameter_u kind_u,
- int deref_size) override
- {
- struct frame_info *caller_frame;
- dwarf2_per_cu_data *caller_per_cu;
- dwarf2_per_objfile *caller_per_objfile;
- struct call_site_parameter *parameter;
- const gdb_byte *data_src;
- size_t size;
-
- caller_frame = get_prev_frame (frame);
-
- parameter = dwarf_expr_reg_to_entry_parameter (frame, kind, kind_u,
- &caller_per_cu,
- &caller_per_objfile);
- data_src = deref_size == -1 ? parameter->value : parameter->data_value;
- size = deref_size == -1 ? parameter->value_size : parameter->data_value_size;
-
- /* DEREF_SIZE size is not verified here. */
- if (data_src == NULL)
- throw_error (NO_ENTRY_VALUE_ERROR,
- _("Cannot resolve DW_AT_call_data_value"));
-
- /* We are about to evaluate an expression in the context of the caller
- of the current frame. This evaluation context may be different from
- the current (callee's) context), so temporarily set the caller's context.
-
- It is possible for the caller to be from a different objfile from the
- callee if the call is made through a function pointer. */
- scoped_restore save_frame = make_scoped_restore (&this->frame,
- caller_frame);
- scoped_restore save_per_cu = make_scoped_restore (&this->per_cu,
- caller_per_cu);
- scoped_restore save_obj_addr = make_scoped_restore (&this->obj_address,
- (CORE_ADDR) 0);
- scoped_restore save_per_objfile = make_scoped_restore (&this->per_objfile,
- caller_per_objfile);
-
- scoped_restore save_arch = make_scoped_restore (&this->gdbarch);
- this->gdbarch = this->per_objfile->objfile->arch ();
- scoped_restore save_addr_size = make_scoped_restore (&this->addr_size);
- this->addr_size = this->per_cu->addr_size ();
-
- this->eval (data_src, size);
- }
};

/* See dwarf2loc.h. */
@@ -1166,13 +1104,9 @@ call_site_parameter_matches (struct call_site_parameter *parameter,
return 0;
}

-/* Fetch call_site_parameter from caller matching KIND and KIND_U.
- FRAME is for callee.
-
- Function always returns non-NULL, it throws NO_ENTRY_VALUE_ERROR
- otherwise. */
+/* See loc.h. */

-static struct call_site_parameter *
+struct call_site_parameter *
dwarf_expr_reg_to_entry_parameter (struct frame_info *frame,
enum call_site_parameter_kind kind,
union call_site_parameter_u kind_u,
diff --git a/gdb/dwarf2/loc.h b/gdb/dwarf2/loc.h
index a729b370e2e..baee63ffccb 100644
--- a/gdb/dwarf2/loc.h
+++ b/gdb/dwarf2/loc.h
@@ -61,6 +61,20 @@ struct value *sect_variable_value (sect_offset sect_off,
dwarf2_per_cu_data *per_cu,
dwarf2_per_objfile *per_objfile);

+/* Fetch call_site_parameter from caller matching KIND and KIND_U.
+ FRAME is for callee.
+
+ Function always returns non-NULL, it throws NO_ENTRY_VALUE_ERROR
+ otherwise. */
+
+struct call_site_parameter *dwarf_expr_reg_to_entry_parameter
+ (struct frame_info *frame,
+ enum call_site_parameter_kind kind,
+ union call_site_parameter_u kind_u,
+ dwarf2_per_cu_data **per_cu_return,
+ dwarf2_per_objfile **per_objfile_return);
+
+
/* Evaluate a location description, starting at DATA and with length
SIZE, to find the current location of variable of TYPE in the context
of FRAME. */
--
2.17.1