Re: [RFA][1/5] New port: Cell BE SPU (dwarf2loc.c fix)

Ulrich Weigand
2006-11-15T21:57:18Z

Jim Blandy wrote:

> This seems fine. I tested it on i686 Fedora Core 5 and didn't see any
> new failures.
>
> Would it be a good idea to introduce a new function, a companion to
> value_from_register, that wraps up the composition of
> value_from_register and value_as_address?

You mean something like the patch below? Tested on spu, s390-ibm-linux
and s390x-ibm-linux.

Bye,
Ulrich

ChangeLog:

* findvar.c (address_from_register): New function.
* value.h (address_from_register): Add prototype.
* dwarf2loc.c (dwarf_expr_read_reg): Use address_from_register.

diff -ur gdb-orig/gdb/dwarf2loc.c gdb-head/gdb/dwarf2loc.c
--- gdb-orig/gdb/dwarf2loc.c 2006-11-10 03:00:22.000000000 +0100
+++ gdb-head/gdb/dwarf2loc.c 2006-11-15 22:12:11.624037552 +0100
@@ -115,24 +115,17 @@
/* Helper functions for dwarf2_evaluate_loc_desc. */

/* Using the frame specified in BATON, return the value of register
- REGNUM, treated as an unsigned integer. */
+ REGNUM, treated as a pointer. */
static CORE_ADDR
dwarf_expr_read_reg (void *baton, int dwarf_regnum)
{
struct dwarf_expr_baton *debaton = (struct dwarf_expr_baton *) baton;
CORE_ADDR result;
- gdb_byte *buf;
- int regnum, regsize;
+ int regnum;

regnum = DWARF2_REG_TO_REGNUM (dwarf_regnum);
- regsize = register_size (current_gdbarch, regnum);
- buf = alloca (regsize);
-
- frame_register_read (debaton->frame, regnum, buf);
- /* NOTE: cagney/2003-05-22: This extract is assuming that a DWARF 2
- address is always unsigned. That may or may not be true. */
- result = extract_unsigned_integer (buf, regsize);
-
+ result = address_from_register (builtin_type_void_data_ptr,
+ regnum, debaton->frame);
return result;
}

diff -ur gdb-orig/gdb/findvar.c gdb-head/gdb/findvar.c
--- gdb-orig/gdb/findvar.c 2006-01-17 23:30:29.000000000 +0100
+++ gdb-head/gdb/findvar.c 2006-11-15 22:09:11.884934888 +0100
@@ -728,6 +728,26 @@
return v;
}

+/* Return contents of register REGNUM in frame FRAME as address,
+ interpreted as value of type TYPE. Will abort if register
+ value is not available. */
+
+CORE_ADDR
+address_from_register (struct type *type, int regnum, struct frame_info *frame)
+{
+ struct value *value;
+ CORE_ADDR result;
+
+ value = value_from_register (type, regnum, frame);
+ gdb_assert (value);
+
+ result = value_as_address (value);
+ release_value (value);
+ value_free (value);
+
+ return result;
+}
+
\f
/* Given a struct symbol for a variable or function,
and a stack frame id,
diff -ur gdb-orig/gdb/value.h gdb-head/gdb/value.h
--- gdb-orig/gdb/value.h 2006-07-13 06:31:42.000000000 +0200
+++ gdb-head/gdb/value.h 2006-11-15 22:10:31.813034144 +0100
@@ -282,6 +282,9 @@
extern struct value *value_from_register (struct type *type, int regnum,
struct frame_info *frame);

+extern CORE_ADDR address_from_register (struct type *type, int regnum,
+ struct frame_info *frame);
+
extern struct value *value_of_variable (struct symbol *var, struct block *b);

extern struct value *value_of_register (int regnum, struct frame_info *frame);