Re: RE: Kernel 2.6.3 patch for Intel Compiler 8.0

From: ingo
Date: Sat Mar 13 2004 - 12:19:17 EST

Hi Jun,

thanks for the script, I'll check it out.
First of all, I am using icc 8.0 (Build 20031016Z Package ID:
l_cc_p_8.0.055) and encountered several problems with the compiler and
Linux kernel 2.6.3.
1.) icc sometimes interprets assembler constraints for inline assembly
in the wrong way (I will check my disk for a sample to prove it).
2.) is it right that the "-fno-common" switch of icc is incompatible to
that of gcc and generates common variables, e.g. in modules?
3.) arch/i386/lib/dec_and_lock.c: I attached the wrong assembler version
generated by icc (with comments).

btw: Could you supply me with the PGO kernel driver for icc, or: where
can I find it?

Rgs, Ingo.

"Nakajima, Jun" <jun.nakajima@xxxxxxxxx> schrieb am 12.03.2004,
> Ingo, Hi
> We tried it (2.6.4) our side. As long as we tested, we did not need _any
> changes_ to the kernel tree, and I guess what you are missing is a shell
> script that calls icc converting the GCC specific options to Intel
> compiler.
> Attached is the script. Just type "make CC=kicc" for example.
> Can you be more specific about the issue with dec_and_lock.c?
> Jun
.globl atomic_dec_and_lock
# parameter 1: 28 + %esp (atomic)
# parameter 2: 32 + %esp (lock)
pushl %esi
pushl %ebx
subl $16, %esp
movl 28(%esp), %ebx # %ebx = atomic
movl (%ebx), %esi # %esi = atomic->counter
movl %esi, (%esp) # (%esp) = counter
addl $-1, %esi # %esi = newcount
je ..B1.5
movl (%ebx), %ecx # %ecx = atomic->counter
movl (%esp), %edx # %edx = counter
movl %ecx, 12(%esp) # 12(%esp) = DUPLICATE OF
# atomic->counter (BUG!)
movl %edx, %eax # %eax = counter
# inline param: "0" (counter)
# Begin ASM
lock; cmpxchgl %esi,12(%esp) # %1 = %esi = newcount
# %2 = 12(%esp) = DUPLCATE OF
# atomic->counter (BUG!)
# End ASM
cmpl %edx, %eax
jne ..B1.2
xorl %eax, %eax
addl $16, %esp
popl %ebx
popl %esi