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-rw-r--r--gas/ChangeLog17
-rw-r--r--gas/config/tc-msp430.c113
-rw-r--r--gas/config/tc-msp430.h8
-rw-r--r--gas/doc/c-msp430.texi15
4 files changed, 143 insertions, 10 deletions
diff --git a/gas/ChangeLog b/gas/ChangeLog
index 1f5d8a0..bc98f76 100644
--- a/gas/ChangeLog
+++ b/gas/ChangeLog
@@ -1,3 +1,20 @@
+2005-08-12 Dmitry Diky <diwil@spec.ru>
+ * config/tc-msp430.c (msp430_enable_relax): New flag.
+ (msp430_enable_polys): Likewise.
+ (OPTION_RELAX): New option.
+ (OPTION_POLYMORPHS): Likewise.
+ (md_longopts): New long options.
+ (md_show_usage): Updated.
+ (md_parse_option): Add new options handler.
+ (msp430_operands): Add check if polymorph insns are enabled.
+ (msp430_force_relocation_local): New function.
+ (md_apply_fix): Now delete relocs according to new flags combination.
+ (msp430_relax_frag): Convert long branches to short branches only if
+ flag msp430_enable_relax is set.
+ * config/tc-msp430.h (TC_FORCE_RELOCATION_LOCAL): Defined.
+ (msp430_force_relocation_local): Likewise.
+ * doc/c-msp430.texi: Describe new options.
+
2005-08-11 Ian Lance Taylor <ian@airs.com>
* Makefile.am ($(srcdir)/make-gas.com): Remove target.
diff --git a/gas/config/tc-msp430.c b/gas/config/tc-msp430.c
index 5b6e196..ed00c69 100644
--- a/gas/config/tc-msp430.c
+++ b/gas/config/tc-msp430.c
@@ -31,6 +31,49 @@
#include "opcode/msp430.h"
#include "safe-ctype.h"
+/*
+ We will disable polymorphs by default because it is dangerous.
+ The potencial problem here is the following: assume we got the
+ following code:
+
+ jump .l1
+ nop
+ jump subroutine ; external symbol
+ .l1:
+ nop
+ ret
+
+ In case of assembly time relaxation we'll get:
+ 0: jmp .l1 <.text +0x08> (reloc deleted)
+ 2: nop
+ 4: br subroutine
+ .l1:
+ 8: nop
+ 10: ret
+
+ If the 'subroutine' wiys thin +-1024 bytes range then linker
+ will produce
+ 0: jmp .text +0x08
+ 2: nop
+ 4: jmp subroutine
+ .l1:
+ 6: nop
+ 8: ret ; 'jmp .text +0x08' will land here. WRONG!!!
+
+
+ The workaround is the following:
+ 1. Declare global var enable_polymorphs which set to 1 via option -mP.
+ 2. Declare global var enable_relax which set to 1 via option -mQ.
+
+ If polymorphs are enabled, and relax isn't, treat all jumps as long jumps,
+ do not delete any relocs and leave them for linker.
+
+ If relax is enabled, relax at assembly time and kill relocs as necessary.
+ */
+
+int msp430_enable_relax;
+int msp430_enable_polys;
+
/* GCC uses the some condition codes which we'll
implement as new polymorph instructions.
@@ -660,6 +703,8 @@ extract_word (char * from, char * to, int limit)
}
#define OPTION_MMCU 'm'
+#define OPTION_RELAX 'Q'
+#define OPTION_POLYMORPHS 'P'
static void
msp430_set_arch (int dummy ATTRIBUTE_UNUSED)
@@ -709,6 +754,17 @@ md_parse_option (int c, char * arg)
as_fatal (_("redefinition of mcu type %s' to %s'"),
msp430_mcu->name, mcu_types[i].name);
return 1;
+ break;
+
+ case OPTION_RELAX:
+ msp430_enable_relax = 1;
+ return 1;
+ break;
+
+ case OPTION_POLYMORPHS:
+ msp430_enable_polys = 1;
+ return 1;
+ break;
}
return 0;
@@ -727,6 +783,8 @@ const char *md_shortopts = "m:";
struct option md_longopts[] =
{
{"mmcu", required_argument, NULL, OPTION_MMCU},
+ {"mP", no_argument, NULL, OPTION_POLYMORPHS},
+ {"mQ", no_argument, NULL, OPTION_RELAX},
{NULL, no_argument, NULL, 0}
};
@@ -758,6 +816,9 @@ md_show_usage (FILE * stream)
" msp430xG437 msp430xG438 msp430G439\n"
" msp430x435 msp430x436 msp430x437\n"
" msp430x447 msp430x448 msp430x449\n"));
+ fprintf (stream,
+ _(" -mQ - enable relaxation at assembly time. DANGEROUS!\n"
+ " -mP - enable polymorph instructions\n"));
show_mcu_list (stream);
}
@@ -1683,6 +1744,12 @@ msp430_operands (struct msp430_opcode_s * opcode, char * line)
break;
case 4: /* Extended jumps. */
+ if (!msp430_enable_polys)
+ {
+ as_bad(_("polymorphs are not enabled. Use -mP option to enable."));
+ break;
+ }
+
line = extract_operand (line, l1, sizeof (l1));
if (l1[0])
{
@@ -1714,6 +1781,11 @@ msp430_operands (struct msp430_opcode_s * opcode, char * line)
break;
case 5: /* Emulated extended branches. */
+ if (!msp430_enable_polys)
+ {
+ as_bad(_("polymorphs are not enabled. Use -mP option to enable."));
+ break;
+ }
line = extract_operand (line, l1, sizeof (l1));
if (l1[0])
{
@@ -1820,9 +1892,24 @@ md_pcrel_from_section (fixS * fixp, segT sec)
return fixp->fx_frag->fr_address + fixp->fx_where;
}
+/* Replaces standard TC_FORCE_RELOCATION_LOCAL.
+ Now it handles the situation when relocations
+ have to be passed to linker. */
+int
+msp430_force_relocation_local(fixS *fixp)
+{
+ if (msp430_enable_polys
+ && !msp430_enable_relax)
+ return 1;
+ else
+ return (!fixp->fx_pcrel
+ || fixp->fx_plt
+ || generic_force_reloc(fixp));
+}
+
+
/* GAS will call this for each fixup. It should store the correct
value in the object file. */
-
void
md_apply_fix (fixS * fixp, valueT * valuep, segT seg)
{
@@ -1879,13 +1966,18 @@ md_apply_fix (fixS * fixp, valueT * valuep, segT seg)
}
}
- switch (fixp->fx_r_type)
+ fixp->fx_no_overflow = 1;
+
+ /* if polymorphs are enabled and relax disabled.
+ do not kill any relocs and pass them to linker. */
+ if (msp430_enable_polys
+ && !msp430_enable_relax)
{
- default:
- fixp->fx_no_overflow = 1;
- break;
- case BFD_RELOC_MSP430_10_PCREL:
- break;
+ if (!fixp->fx_addsy || (fixp->fx_addsy
+ && S_GET_SEGMENT (fixp->fx_addsy) == absolute_section))
+ fixp->fx_done = 1; /* it is ok to kill 'abs' reloc */
+ else
+ fixp->fx_done = 0;
}
if (fixp->fx_done)
@@ -2185,6 +2277,13 @@ msp430_relax_frag (segT seg ATTRIBUTE_UNUSED, fragS * fragP,
aim = S_GET_VALUE (symbolP) - fragP->fr_address - fragP->fr_fix;
}
+ if (!msp430_enable_relax)
+ {
+ /* Relaxation is not enabled. So, make all jump as long ones
+ by setting 'aim' to quite high value. */
+ aim = 0x7fff;
+ }
+
this_state = fragP->fr_subtype;
start_type = this_type = table + this_state;
diff --git a/gas/config/tc-msp430.h b/gas/config/tc-msp430.h
index 632e2a9..9fef126 100644
--- a/gas/config/tc-msp430.h
+++ b/gas/config/tc-msp430.h
@@ -112,3 +112,11 @@ extern long md_pcrel_from_section (struct fix *, segT);
#define md_relax_frag(SEG, FRAGP, STRETCH) \
msp430_relax_frag (SEG, FRAGP, STRETCH)
extern long msp430_relax_frag (segT, fragS *, long);
+
+#define TC_FORCE_RELOCATION_LOCAL(FIX) \
+ msp430_force_relocation_local(FIX)
+extern int msp430_force_relocation_local(struct fix *);
+
+
+extern int msp430_enable_relax;
+extern int msp430_enable_polys;
diff --git a/gas/doc/c-msp430.texi b/gas/doc/c-msp430.texi
index b398952..33f3e83 100644
--- a/gas/doc/c-msp430.texi
+++ b/gas/doc/c-msp430.texi
@@ -26,8 +26,17 @@
@section Options
@cindex MSP 430 options (none)
@cindex options for MSP430 (none)
-@code{@value{AS}} has only -m flag which selects the mpu arch. Currently has
-no effect.
+@table @code
+
+@item -m
+select the mpu arch. Currently has no effect.
+@item -mP
+enables polymorph instructions handler.
+
+@item -mQ
+enables relaxation at assembly time. DANGEROUS!
+
+@end table
@node MSP430 Syntax
@section Syntax
@@ -214,7 +223,7 @@ This directive instructs assembler to add new profile entry to the object file.
additional pseudo-instructions are needed on this family.
For information on the 430 machine instruction set, see @cite{MSP430
-User's Manual, document slau049b}, Texas Instrument, Inc.
+User's Manual, document slau049d}, Texas Instrument, Inc.
@node MSP430 Profiling Capability
@section Profiling Capability
generated by cgit v1.1 at 2024-11-27 11:42:32 +0000