[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Qemu-devel] Bug in s390 instruction emulation
From: |
Torbjörn Granlund |
Subject: |
[Qemu-devel] Bug in s390 instruction emulation |
Date: |
Wed, 03 Dec 2014 22:16:37 +0100 |
User-agent: |
Gnus/5.11 (Gnus v5.11) Emacs/22.3 (berkeley-unix) |
The s390 instruction emulation makes GMP fail most of its tests.
I have isolated one of the problems:
How to reproduce:
gcc m.c x.s
./a.out
Correct output on actual hardware:
ffffffff
Incorrect output using QEMU 2.2.0 rc4:
0
File m.c:
#include <stdio.h>
int foo();
int main() { printf("%x\n", foo()); return 0; }
File x.s:
.text
.align 8
.globl foo
.type foo,@function
foo: lghi %r2, 0
lghi %r3, 1
slgr %r2, %r3
slbgr %r3, %r3
slbgr %r2, %r2
br %r14
(This is using "user mode" emulation. System mode emulation doesn't
work at all, and never did, as I am sure you know. I suppose getting
basic instruction emulation correct is a good first step.)
--
Torbjörn
Please encrypt, key id 0xC8601622
- [Qemu-devel] Bug in s390 instruction emulation,
Torbjörn Granlund <=