From: "H . J . Lu" <hjl@lucon.org>
To: gcc@gcc.gnu.org, binutils@sourceware.cygnus.com, linux-mips@oss.sgi.com
Subject: DWARF2 exception doesn't work with gcc and gas on MIPS.
Date: Wed, 13 Jun 2001 21:29:40 -0700 [thread overview]
Message-ID: <20010613212940.A22683@lucon.org> (raw)
In the MIPS gas, there is
case M_JAL_A:
if (mips_pic == NO_PIC)
macro_build ((char *) NULL, &icnt, &offset_expr, "jal", "a");
else if (mips_pic == SVR4_PIC)
{
/* If this is a reference to an external symbol, and we are
using a small GOT, we want
lw $25,<sym>($gp) (BFD_RELOC_MIPS_CALL16)
nop
jalr $25
nop
lw $gp,cprestore($sp)
The cprestore value is set using the .cprestore
pseudo-op. If we are using a big GOT, we want
lui $25,<sym> (BFD_RELOC_MIPS_CALL_HI16)
addu $25,$25,$gp
lw $25,<sym>($25) (BFD_RELOC_MIPS_CALL_LO16)
nop
jalr $25
nop
lw $gp,cprestore($sp)
If the symbol is not external, we want
lw $25,<sym>($gp) (BFD_RELOC_MIPS_GOT16)
nop
addiu $25,$25,<sym> (BFD_RELOC_LO16)
jalr $25
nop
lw $gp,cprestore($sp) */
When gcc emits
$LEHB5:
la $25,foobar
jal $31,$25
$LEHE5:
It doesn't work since
jal $31,$25
is expanded to
jalr $25
nop
lw $gp,cprestore($sp)
Now we have
$LEHB5:
la $25,foobar
jalr $25
nop
lw $gp,cprestore($sp)
$LEHE5:
When foobar throws an exception, GP won't get restored. What we want is
$LEHB5:
la $25,foobar
jalr $25
nop
$LEHE5:
lw $gp,cprestore($sp)
Does anyone have any suggestions how to fix it?
Thanks.
H.J.
next reply other threads:[~2001-06-14 4:29 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2001-06-14 4:29 H . J . Lu [this message]
2001-06-14 5:50 ` DWARF2 exception doesn't work with gcc and gas on MIPS Ian Lance Taylor
2001-06-14 5:53 ` Ian Lance Taylor
2001-06-14 6:23 ` H . J . Lu
2001-06-14 17:19 ` Richard Henderson
2001-06-14 18:41 ` H . J . Lu
2001-06-14 19:05 ` Richard Henderson
2001-06-14 19:25 ` H . J . Lu
2001-06-14 19:42 ` Richard Henderson
2001-06-14 19:55 ` H . J . Lu
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