Re: [PATCH] Use read_memory_unsigned_integer when reading to CORE_ADDR

[Klee Dienes <klee at apple dot com>]

On Sunday, October 6, 2002, at 11:09 AM, Daniel Jacobowitz wrote:

> Might want to use alloca (TYPE_LENGTH (builtin_type_void_data_ptr)).
Love to; I had been under the (apparently mistaken) impression that 
alloca was deprecated for new code.

> > Aside from the intimidating comments in findvar.c, this would seem a
> > good candidate for extract_address ... though a similar modification
> > would have to be made to it to handle the sign-extension as well.
> >
> > Or alternately, I could just leave well-enough alone, and be careful 
> > to
> > truncate CORE_ADDRs to 32 bits in our target xfer_memory code (or the
> > MIPS code could sign-extend it in the same place).
> Well, I think a general read_memory_typed_address (returning CORE_ADDR,
> and honoroing POINTER_TO_ADDRESS) would be the way to go here.
That sounds good to me; how about the following?  I removed the patch 
to symfile.c, as it's commented out anyway, and probably not worth the 
effort.  My one concern is that I don't currently have a good system to 
test the part of the patch that affects blockframe.c.

2002-10-06  Klee Dienes  <kdienes@apple.com>

        * findvar.c (read_memory_typed_address): New function.
        * gdbcore.h (read_memory_typed_address): Add prototype.
        * blockframe.c (sigtramp_saved_pc): Use
        read_memory_typed_address to read a value destined for a
        CORE_ADDR, not read_memory_integer.
        * f-valprint.c (f77_get_dynamic_upperbound): Ditto.
        (f77_get_dynamic_lowerbound): Ditto.

diff -u /home/klee/source/cygnus.cygnus/gdb/gdbcore.h ./gdbcore.h
--- /home/klee/source/cygnus.cygnus/gdb/gdbcore.h	Wed Dec 19 15:54:26 
2001
+++ ./gdbcore.h	Sun Oct  6 09:18:11 2002
@@ -64,8 +64,15 @@

 /* Read a null-terminated string from the debuggee's memory, given 
address,
  * a buffer into which to place the string, and the maximum available 
space */
+
 extern void read_memory_string (CORE_ADDR, char *, int);

+/* Read the pointer of type TYPE at BUF, and return the address it
+   represents. */
+
+CORE_ADDR
+read_memory_typed_address (CORE_ADDR addr, struct type *type);
+
 /* This takes a char *, not void *.  This is probably right, because
    passing in an int * or whatever is wrong with respect to
    byteswapping, alignment, different sizes for host vs. target types,
diff -u /home/klee/source/cygnus.cygnus/gdb/corefile.c ./corefile.c
--- /home/klee/source/cygnus.cygnus/gdb/corefile.c	Thu May 30 15:41:24 
2002
+++ ./corefile.c	Sun Oct  6 09:18:11 2002
@@ -356,6 +356,14 @@
     }
 }

+CORE_ADDR
+read_memory_typed_address (CORE_ADDR addr, struct type *type)
+{
+  char *buf = alloca (TYPE_LENGTH (type));
+  read_memory (addr, buf, TYPE_LENGTH (type));
+  return extract_typed_address (buf, type);
+}
+
 /* Same as target_write_memory, but report an error if can't write.  */
 void
 write_memory (CORE_ADDR memaddr, char *myaddr, int len)
diff -u /home/klee/source/cygnus.cygnus/gdb/blockframe.c ./blockframe.c
--- /home/klee/source/cygnus.cygnus/gdb/blockframe.c	Mon Sep 30 
18:24:01 2002
+++ ./blockframe.c	Sun Oct  6 09:35:42 2002
@@ -1035,19 +1035,17 @@
   buf = alloca (ptrbytes);
   /* Get sigcontext address, it is the third parameter on the stack.  
*/
   if (frame->next)
-    sigcontext_addr = read_memory_integer (FRAME_ARGS_ADDRESS 
(frame->next)
-					   + FRAME_ARGS_SKIP
-					   + sigcontext_offs,
-					   ptrbytes);
+    sigcontext_addr = read_memory_typed_address
+      (FRAME_ARGS_ADDRESS (frame->next) + FRAME_ARGS_SKIP + 
sigcontext_offs,
+       builtin_type_void_data_ptr);
   else
-    sigcontext_addr = read_memory_integer (read_register (SP_REGNUM)
-					   + sigcontext_offs,
-					   ptrbytes);
+    sigcontext_addr = read_memory_typed_address
+      (read_register (SP_REGNUM) + sigcontext_offs, 
builtin_type_void_data_ptr);

   /* Don't cause a memory_error when accessing sigcontext in case the 
stack
      layout has changed or the stack is corrupt.  */
   target_read_memory (sigcontext_addr + SIGCONTEXT_PC_OFFSET, buf, 
ptrbytes);
-  return extract_unsigned_integer (buf, ptrbytes);
+  return extract_typed_address (buf, builtin_type_void_data_ptr);
 }
 #endif /* SIGCONTEXT_PC_OFFSET */

diff -u /home/klee/source/cygnus.cygnus/gdb/f-valprint.c ./f-valprint.c
--- /home/klee/source/cygnus.cygnus/gdb/f-valprint.c	Tue Mar  6 
18:57:08 2001
+++ ./f-valprint.c	Sun Oct  6 09:18:11 2002
@@ -102,9 +102,9 @@
       if (current_frame_addr > 0)
 	{
 	  ptr_to_lower_bound =
-	    read_memory_integer (current_frame_addr +
-				 TYPE_ARRAY_LOWER_BOUND_VALUE (type),
-				 4);
+	    read_memory_typed_address (current_frame_addr +
+				       TYPE_ARRAY_LOWER_BOUND_VALUE (type),
+				       builtin_type_void_data_ptr);
 	  *lower_bound = read_memory_integer (ptr_to_lower_bound, 4);
 	}
       else
@@ -165,9 +165,9 @@
       if (current_frame_addr > 0)
 	{
 	  ptr_to_upper_bound =
-	    read_memory_integer (current_frame_addr +
-				 TYPE_ARRAY_UPPER_BOUND_VALUE (type),
-				 4);
+	    read_memory_typed_address (current_frame_addr +
+				       TYPE_ARRAY_UPPER_BOUND_VALUE (type),
+				       builtin_type_void_data_ptr);
 	  *upper_bound = read_memory_integer (ptr_to_upper_bound, 4);
 	}
       else