[rfc] msym.tdep_flags

[mec dot gnu at mindspring dot com (Michael Elizabeth Chastain)]

Here is the next step in my project to get rid of msymbol.info.

msymbol.info originally had three uses:

  (1) coff storage class, mercy-killed by elena
  (2) elf symbol size, moved to a separate field by mec
  (3) target-dependent flag bits

I would like to go after (3) the same way I went after (2).
I want to do this:

  (3A) add a "tdep_flags" field to struct minimal_symbol
  (3B) convert each *-tdep.c file to use the new field, one by one

Here are some diffs to illustrate the idea.  These are just to
show the idea -- I'm asking for comments, not approval.

Should I pursue this approach, or should I do something different?

Michael C

Index: symtab.h
===================================================================
RCS file: /cvs/src/src/gdb/symtab.h,v
retrieving revision 1.83
diff -u -r1.83 symtab.h
--- symtab.h	11 Nov 2003 20:04:52 -0000	1.83
+++ symtab.h	11 Nov 2003 20:17:02 -0000
@@ -336,6 +336,9 @@
   char *filename;
 #endif
 
+  /* Target-specific flag bits.  */
+  unsigned int tdep_flags : 8;
+
   /* Classification type for this minimal symbol.  */
 
   ENUM_BITFIELD(minimal_symbol_type) type : 8;
@@ -353,6 +356,7 @@
 
 #define MSYMBOL_INFO(msymbol)		(msymbol)->info
 #define MSYMBOL_SIZE(msymbol)		(msymbol)->size
+#define MSYMBOL_TDEP_FLAGS(msymbol)	(msymbol)->tdep_flags
 #define MSYMBOL_TYPE(msymbol)		(msymbol)->type
 
Index: arm-tdep.c
===================================================================
RCS file: /cvs/src/src/gdb/arm-tdep.c,v
retrieving revision 1.155
diff -u -r1.155 arm-tdep.c
--- arm-tdep.c	11 Nov 2003 20:04:52 -0000	1.155
+++ arm-tdep.c	11 Nov 2003 20:37:03 -0000
@@ -80,18 +80,16 @@
 #endif
 
 /* Macros for setting and testing a bit in a minimal symbol that marks
-   it as Thumb function.  The MSB of the minimal symbol's "info" field
-   is used for this purpose.
+   it as Thumb function.
 
    MSYMBOL_SET_SPECIAL	Actually sets the "special" bit.
    MSYMBOL_IS_SPECIAL   Tests the "special" bit in a minimal symbol.  */
 
 #define MSYMBOL_SET_SPECIAL(msym)					\
-	MSYMBOL_INFO (msym) = (char *) (((long) MSYMBOL_INFO (msym))	\
-					| 0x80000000)
+	MSYMBOL_TDEP_FLAGS(msym) |= 0x01
 
 #define MSYMBOL_IS_SPECIAL(msym)				\
-	(((long) MSYMBOL_INFO (msym) & 0x80000000) != 0)
+	((MSYMBOL_TDEP_FLAGS(msym)) & 0x01 != 0)
 
 /* The list of available "set arm ..." and "show arm ..." commands.  */
 static struct cmd_list_element *setarmcmdlist = NULL;
Index: m68hc11-tdep.c
===================================================================
RCS file: /cvs/src/src/gdb/m68hc11-tdep.c,v
retrieving revision 1.93
diff -u -r1.93 m68hc11-tdep.c
--- m68hc11-tdep.c	11 Nov 2003 20:04:52 -0000	1.93
+++ m68hc11-tdep.c	11 Nov 2003 20:37:03 -0000
@@ -49,26 +49,22 @@
    type the function is using.  This is used for prologue and frame
    analysis to compute correct stack frame layout.
    
-   The MSB of the minimal symbol's "info" field is used for this purpose.
-
    MSYMBOL_SET_RTC	Actually sets the "RTC" bit.
    MSYMBOL_SET_RTI	Actually sets the "RTI" bit.
    MSYMBOL_IS_RTC       Tests the "RTC" bit in a minimal symbol.
    MSYMBOL_IS_RTI       Tests the "RTC" bit in a minimal symbol.  */
 
 #define MSYMBOL_SET_RTC(msym)                                           \
-        MSYMBOL_INFO (msym) = (char *) (((long) MSYMBOL_INFO (msym))	\
-					| 0x80000000)
+	MSYMBOL_TDEP_FLAGS (msym) |= 0x01
 
 #define MSYMBOL_SET_RTI(msym)                                           \
-        MSYMBOL_INFO (msym) = (char *) (((long) MSYMBOL_INFO (msym))	\
-					| 0x40000000)
+	MSYMBOL_TDEP_FLAGS (msym) |= 0x02
 
 #define MSYMBOL_IS_RTC(msym)				\
-	(((long) MSYMBOL_INFO (msym) & 0x80000000) != 0)
+	((MSYMBOL_TDEP_FLAGS (msym) & 0x01) != 0)
 
 #define MSYMBOL_IS_RTI(msym)				\
-	(((long) MSYMBOL_INFO (msym) & 0x40000000) != 0)
+  	((MSYMBOL_TDEP_FLAGS (msym) & 0x02) != 0)
 
 enum insn_return_kind {
   RETURN_RTS,
Index: mips-tdep.c
===================================================================
RCS file: /cvs/src/src/gdb/mips-tdep.c,v
retrieving revision 1.244
diff -u -r1.244 mips-tdep.c
--- mips-tdep.c	11 Nov 2003 20:04:52 -0000	1.244
+++ mips-tdep.c	11 Nov 2003 20:37:09 -0000
@@ -239,8 +239,7 @@
 {
   if (((elf_symbol_type *)(sym))->internal_elf_sym.st_other == STO_MIPS16) 
     { 
-      MSYMBOL_INFO (msym) = (char *) 
-	(((long) MSYMBOL_INFO (msym)) | 0x80000000); 
+      MSYMBOL_TDEP_FLAGS (msym) |= 0x01;
       SYMBOL_VALUE_ADDRESS (msym) |= 1; 
     } 
 }
@@ -248,7 +247,7 @@
 static int
 msymbol_is_special (struct minimal_symbol *msym)
 {
-  return (((long) MSYMBOL_INFO (msym) & 0x80000000) != 0);
+  return ((MSYMBOL_TDEP_FLAGS (msym) & 0x01) != 0);
 }
 
 static long
Index: sh64-tdep.c
===================================================================
RCS file: /cvs/src/src/gdb/sh64-tdep.c,v
retrieving revision 1.12
diff -u -r1.12 sh64-tdep.c
--- sh64-tdep.c	11 Nov 2003 20:04:52 -0000	1.12
+++ sh64-tdep.c	11 Nov 2003 20:37:11 -0000
@@ -206,7 +206,7 @@
    MSYMBOL_IS_SPECIAL   tests the "special" bit in a minimal symbol  */
 
 #define MSYMBOL_IS_SPECIAL(msym) \
-  (((long) MSYMBOL_INFO (msym) & 0x80000000) != 0)
+  ((MSYMBOL_TDEP_FLAGS (msym) & 0x01) != 0)
 
 static void
 sh64_elf_make_msymbol_special (asymbol *sym, struct minimal_symbol *msym)
@@ -216,7 +216,7 @@
 
   if (((elf_symbol_type *)(sym))->internal_elf_sym.st_other == STO_SH5_ISA32)
     {
-      MSYMBOL_INFO (msym) = (char *) (((long) MSYMBOL_INFO (msym)) | 0x80000000);
+      MSYMBOL_TDEP_FLAGS (msym) |= 0x01;
       SYMBOL_VALUE_ADDRESS (msym) |= 1;
     }
 }