Bug of gas (binutils-2.9.1.0.23): Wrong code for SETHI on SPARC

H.J. Lu hjl@lucon.org
Fri Apr 2 16:10:00 GMT 1999


> 
> gas out of binutils-2.9.1.0.23 (and older versions) has a severe bug
> for the SPARC platform (sparc-sun-solaris2.6), i.e. it generates
> wrong code for
> 
>         sethi   0x4000,%i0
> 
> (and probably in all other cases where sethi is used without the
> %hi(...)-construct).
> 
> The sethi instruction has following suggested assembly syntax
> (see SPARC Architecture Manual):
> 
>         sethi   const22,reg
> 
> const22 is a 22-bit constant that is placed by sethi in the most
> significant 22 bits of reg (while it zeroes the 10 least significant
> bits of reg). Therefore we would expect the value 0x100000 in %i0
> after the execution of ``sethi 16384''. Instead of this, gas
> modifies the given constant such that 0x4000 will be found in %i0
> afterwards. This would have been equivalent to
> 
>         sethi %hi(0x4000),%i0
> 

Hi,

Here is a new patch. Please discard my last patch to tc-sparc.c.
Let me know what you get.

Thanks.


H.J.
---
Fri Apr  2 16:05:25 1999  H.J. Lu  (hjl@gnu.org)

	* sparc-opc.c: Change "sethi" from "h,d" to "n,d".

Index: ChangeLog.linux
===================================================================
RCS file: /local/work/cvs/gnu/binutils/opcodes/ChangeLog.linux,v
retrieving revision 1.40
diff -u -p -r1.40 ChangeLog.linux
--- ChangeLog.linux	1999/03/31 17:24:49	1.40
+++ ChangeLog.linux	1999/04/03 00:05:33
@@ -1,3 +1,5 @@
+Fri Apr  2 16:05:25 1999  H.J. Lu  (hjl@gnu.org)
+
 Sun Mar 28 11:48:17 1999  H.J. Lu  (hjl@gnu.org)
 
 	* i386-dis.c (INSN_FWAIT): New, defined.
Index: sparc-opc.c
===================================================================
RCS file: /local/work/cvs/gnu/binutils/opcodes/sparc-opc.c,v
retrieving revision 1.7
diff -u -p -r1.7 sparc-opc.c
--- sparc-opc.c	1998/12/05 03:38:56	1.7
+++ sparc-opc.c	1999/04/03 00:00:22
@@ -1379,7 +1379,7 @@ CONDFC  ("fbule", "cb013", 0xe, 0),
 { "setsw",	F2(0x0, 0x4), F2(~0x0, ~0x4), "Sh,d", F_ALIAS, v9 },
 { "setx",	F2(0x0, 0x4), F2(~0x0, ~0x4), "S0,1,d", F_ALIAS, v9 },
 
-{ "sethi",	F2(0x0, 0x4), F2(~0x0, ~0x4), "h,d", 0, v6 },
+{ "sethi",	F2(0x0, 0x4), F2(~0x0, ~0x4), "n,d", 0, v6 },
 
 { "taddcc",	F3(2, 0x20, 0), F3(~2, ~0x20, ~0)|ASI(~0),	"1,2,d", 0, v6 },
 { "taddcc",	F3(2, 0x20, 1), F3(~2, ~0x20, ~1),		"1,i,d", 0, v6 },



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