[PATCH] MIPS gas: Fix macro expansions for .set noat
Thiemo Seufer
ica2_ts@csv.ica.uni-stuttgart.de
Thu Feb 17 07:10:00 GMT 2005
Maciej W. Rozycki wrote:
> On Wed, 16 Feb 2005, Thiemo Seufer wrote:
>
> > > More comments about that change -- as I understand our policy wrt $at
> > > being used with ".set noat" in effect is to go for it regardless and only
> > > issue a warning (that can be converted to an error with --fatal-warnings).
> > > Therefore we shouldn't use as_bad() in this case.
> >
> > IMHO it should be an error if the result can't work at all. I don't
> > see a case where overwriting the base register before its use could
> > be the programmers intention.
>
> I do agree it's of questionable use and I proposed changing it a few
> years ago, but I got a response as I expressed above. Then if it's to be
> done, it should be done consistently for all cases -- replacing respective
> as_warn() calls with as_bad() ones should be the right way.
Hm, OTOH it could simply be sloppy coding, and falling over it
is not necessarily the right thing to do. I plan to commit the
appended patch, it partially reverts the earlier change.
Comments?
Thiemo
2005-02-16 Thiemo Seufer <seufer@csv.ica.uni-stuttgart.de>
/gas/ChangeLog
* config/tc-mips.c (macro): Don't fail but warn on $at uses
after .set noat, it may only be sloppy coding. Don't try to
avoid $at use by sacrificing the target register before it is
stored, it won't work.
/gas/testsuite/ChangeLog
* gas/mips/noat-1.s, gas/mips/noat-1.d, gas/mips/noat-2.s,
gas/mips/noat2.l, gas/mips/noat-3.s, gas/mips/noat-3.l,
gas/mips/noat-4.s, gas/mips/noat-4.l, gas/mips/noat-5.s,
gas/mips/noat-5.l, gas/mips/noat-6.s, gas/mips/noat-6.l,
gas/mips/noat-7.s, gas/mips/noat-7.l: New files, testcases for
.set noat and macro expansion.
* gas/mips/mips.exp: Run new testcases.
Index: gas/config/tc-mips.c
===================================================================
RCS file: /cvs/src/src/gas/config/tc-mips.c,v
retrieving revision 1.282
diff -u -p -r1.282 tc-mips.c
--- gas/config/tc-mips.c 16 Feb 2005 15:49:13 -0000 1.282
+++ gas/config/tc-mips.c 16 Feb 2005 23:26:33 -0000
@@ -5761,23 +5761,14 @@ macro (struct mips_cl_insn *ip)
case M_LWU_AB:
s = "lwu";
ld:
- /* XXX Why don't we try to use AT for all expansions? */
- if (!mips_opts.noat && (breg == treg || coproc || lr))
+ if (breg == treg || coproc || lr)
{
tempreg = AT;
used_at = 1;
}
- else if (breg == treg
- && (offset_expr.X_op != O_constant
- || (offset_expr.X_add_number > 0x7fff
- || offset_expr.X_add_number < -0x8000)))
- {
- as_bad(_("load expansion needs $at register"));
- }
else
{
tempreg = treg;
- used_at = 0;
}
goto ld_st;
case M_SB_AB:
@@ -5847,23 +5838,8 @@ macro (struct mips_cl_insn *ip)
case M_SDR_AB:
s = "sdr";
st:
- if (!mips_opts.noat)
- {
- tempreg = AT;
- used_at = 1;
- }
- else if (breg == treg
- && (offset_expr.X_op != O_constant
- || (offset_expr.X_add_number > 0x7fff
- || offset_expr.X_add_number < -0x8000)))
- {
- as_bad(_("store expansion needs $at register"));
- }
- else
- {
- tempreg = treg;
- used_at = 0;
- }
+ tempreg = AT;
+ used_at = 1;
ld_st:
/* Itbl support may require additional care here. */
if (mask == M_LWC1_AB
Index: gas/testsuite/gas/mips/mips.exp
===================================================================
RCS file: /cvs/src/src/gas/testsuite/gas/mips/mips.exp,v
retrieving revision 1.98
diff -u -p -r1.98 mips.exp
--- gas/testsuite/gas/mips/mips.exp 15 Feb 2005 19:57:53 -0000 1.98
+++ gas/testsuite/gas/mips/mips.exp 16 Feb 2005 23:26:35 -0000
@@ -738,4 +738,12 @@ if { [istarget mips*-*-*] } then {
run_dump_test "macro-warn-1-n32"
run_dump_test "macro-warn-2-n32"
}
+
+ run_dump_test "noat-1"
+ run_list_test "noat-2" ""
+ run_list_test "noat-3" ""
+ run_list_test "noat-4" ""
+ run_list_test "noat-5" ""
+ run_list_test "noat-6" ""
+ run_list_test "noat-7" ""
}
Index: gas/testsuite/gas/mips/noat-1.d
===================================================================
RCS file: gas/testsuite/gas/mips/noat-1.d
diff -N gas/testsuite/gas/mips/noat-1.d
--- /dev/null 1 Jan 1970 00:00:00 -0000
+++ gas/testsuite/gas/mips/noat-1.d 16 Feb 2005 23:26:35 -0000
@@ -0,0 +1,15 @@
+#as: -32
+#objdump: -dr
+
+.*: +file format .*mips
+
+Disassembly of section \.text:
+
+00000000 <\.text>:
+ 0: 8f7b7fff lw k1,32767\(k1\)
+ 4: 00000000 nop
+ 8: 8f7b8000 lw k1,-32768\(k1\)
+ c: 00000000 nop
+ 10: af7b7fff sw k1,32767\(k1\)
+ 14: af7b8000 sw k1,-32768\(k1\)
+ \.\.\.
Index: gas/testsuite/gas/mips/noat-1.s
===================================================================
RCS file: gas/testsuite/gas/mips/noat-1.s
diff -N gas/testsuite/gas/mips/noat-1.s
--- /dev/null 1 Jan 1970 00:00:00 -0000
+++ gas/testsuite/gas/mips/noat-1.s 16 Feb 2005 23:26:35 -0000
@@ -0,0 +1,7 @@
+ .set noat
+ lw $27, 0x7fff($27)
+ lw $27, -0x8000($27)
+ sw $27, 0x7fff($27)
+ sw $27, -0x8000($27)
+
+ .space 8
Index: gas/testsuite/gas/mips/noat-2.l
===================================================================
RCS file: gas/testsuite/gas/mips/noat-2.l
diff -N gas/testsuite/gas/mips/noat-2.l
--- /dev/null 1 Jan 1970 00:00:00 -0000
+++ gas/testsuite/gas/mips/noat-2.l 16 Feb 2005 23:26:35 -0000
@@ -0,0 +1,2 @@
+.*\.s: Assembler messages:
+.*\.s:2: Warning: Macro used \$at after "\.set noat"
Index: gas/testsuite/gas/mips/noat-2.s
===================================================================
RCS file: gas/testsuite/gas/mips/noat-2.s
diff -N gas/testsuite/gas/mips/noat-2.s
--- /dev/null 1 Jan 1970 00:00:00 -0000
+++ gas/testsuite/gas/mips/noat-2.s 16 Feb 2005 23:26:35 -0000
@@ -0,0 +1,4 @@
+ .set noat
+ lw $27, 0x8000($27)
+
+ .space 8
Index: gas/testsuite/gas/mips/noat-3.l
===================================================================
RCS file: gas/testsuite/gas/mips/noat-3.l
diff -N gas/testsuite/gas/mips/noat-3.l
--- /dev/null 1 Jan 1970 00:00:00 -0000
+++ gas/testsuite/gas/mips/noat-3.l 16 Feb 2005 23:26:35 -0000
@@ -0,0 +1,2 @@
+.*\.s: Assembler messages:
+.*\.s:2: Warning: Macro used \$at after "\.set noat"
Index: gas/testsuite/gas/mips/noat-3.s
===================================================================
RCS file: gas/testsuite/gas/mips/noat-3.s
diff -N gas/testsuite/gas/mips/noat-3.s
--- /dev/null 1 Jan 1970 00:00:00 -0000
+++ gas/testsuite/gas/mips/noat-3.s 16 Feb 2005 23:26:35 -0000
@@ -0,0 +1,4 @@
+ .set noat
+ lw $27, -0x8001($27)
+
+ .space 8
Index: gas/testsuite/gas/mips/noat-4.l
===================================================================
RCS file: gas/testsuite/gas/mips/noat-4.l
diff -N gas/testsuite/gas/mips/noat-4.l
--- /dev/null 1 Jan 1970 00:00:00 -0000
+++ gas/testsuite/gas/mips/noat-4.l 16 Feb 2005 23:26:35 -0000
@@ -0,0 +1,2 @@
+.*\.s: Assembler messages:
+.*\.s:2: Warning: Macro used \$at after "\.set noat"
Index: gas/testsuite/gas/mips/noat-4.s
===================================================================
RCS file: gas/testsuite/gas/mips/noat-4.s
diff -N gas/testsuite/gas/mips/noat-4.s
--- /dev/null 1 Jan 1970 00:00:00 -0000
+++ gas/testsuite/gas/mips/noat-4.s 16 Feb 2005 23:26:35 -0000
@@ -0,0 +1,4 @@
+ .set noat
+ lw $27, symbol($27)
+
+ .space 8
Index: gas/testsuite/gas/mips/noat-5.l
===================================================================
RCS file: gas/testsuite/gas/mips/noat-5.l
diff -N gas/testsuite/gas/mips/noat-5.l
--- /dev/null 1 Jan 1970 00:00:00 -0000
+++ gas/testsuite/gas/mips/noat-5.l 16 Feb 2005 23:26:35 -0000
@@ -0,0 +1,2 @@
+.*\.s: Assembler messages:
+.*\.s:2: Warning: Macro used \$at after "\.set noat"
Index: gas/testsuite/gas/mips/noat-5.s
===================================================================
RCS file: gas/testsuite/gas/mips/noat-5.s
diff -N gas/testsuite/gas/mips/noat-5.s
--- /dev/null 1 Jan 1970 00:00:00 -0000
+++ gas/testsuite/gas/mips/noat-5.s 16 Feb 2005 23:26:35 -0000
@@ -0,0 +1,4 @@
+ .set noat
+ sw $27, 0x8000($27)
+
+ .space 8
Index: gas/testsuite/gas/mips/noat-6.l
===================================================================
RCS file: gas/testsuite/gas/mips/noat-6.l
diff -N gas/testsuite/gas/mips/noat-6.l
--- /dev/null 1 Jan 1970 00:00:00 -0000
+++ gas/testsuite/gas/mips/noat-6.l 16 Feb 2005 23:26:35 -0000
@@ -0,0 +1,2 @@
+.*\.s: Assembler messages:
+.*\.s:2: Warning: Macro used \$at after "\.set noat"
Index: gas/testsuite/gas/mips/noat-6.s
===================================================================
RCS file: gas/testsuite/gas/mips/noat-6.s
diff -N gas/testsuite/gas/mips/noat-6.s
--- /dev/null 1 Jan 1970 00:00:00 -0000
+++ gas/testsuite/gas/mips/noat-6.s 16 Feb 2005 23:26:35 -0000
@@ -0,0 +1,4 @@
+ .set noat
+ sw $27, -0x8001($27)
+
+ .space 8
Index: gas/testsuite/gas/mips/noat-7.l
===================================================================
RCS file: gas/testsuite/gas/mips/noat-7.l
diff -N gas/testsuite/gas/mips/noat-7.l
--- /dev/null 1 Jan 1970 00:00:00 -0000
+++ gas/testsuite/gas/mips/noat-7.l 16 Feb 2005 23:26:35 -0000
@@ -0,0 +1,2 @@
+.*\.s: Assembler messages:
+.*\.s:2: Warning: Macro used \$at after "\.set noat"
Index: gas/testsuite/gas/mips/noat-7.s
===================================================================
RCS file: gas/testsuite/gas/mips/noat-7.s
diff -N gas/testsuite/gas/mips/noat-7.s
--- /dev/null 1 Jan 1970 00:00:00 -0000
+++ gas/testsuite/gas/mips/noat-7.s 16 Feb 2005 23:26:35 -0000
@@ -0,0 +1,4 @@
+ .set noat
+ sw $27, symbol($27)
+
+ .space 8
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