asm syntax

Accelerated Computing HPC Compilers Legacy PGI Compilers
1

I am looking for documentation on the asm syntax that I can use with the 6.1 PGI compilers. I have a little snippet like

asm volatile (“lock; incl %0”
: “=m”(mValue)
: “m”(mValue));

and I get compilation errors along the lines of

/tmp/pgCCbaaaafqpaA.s: Assembler messages:
/tmp/pgCCbaaaafqpaA.s:103: Error: bad register name `%0’

which seems to strongly suggest that the asm syntax that I would have used with a gnu compiler will not work for me here (this does work with my gnu compilers). There is presumably a document on how to use the newly introduced asm and I would like to have a copy of that. I’ve searched the web and this site (in vain evidently).

Thanks in advance.

2

Hi esmyth,

Which compiler are you using? With PGI 6.1, extended asm is only supported in C but it appears that you might be compiling with the C++ compiler. C++ extended asm support will available with the up coming 6.2 release.

-Mat

3

Hello Mat:
I am using pgCC for this portion. You are right. I was unaware of this “inconsistency” between the pgcc and pgCC compilers in 6.1. I gather 6.2 is close at hand. In the meantime, I will try to move this code to a C translation unit and will thus inclur the overhead of an extra function call (which may turn out to be a bad deal). Nevertheless, it should work.
Thanks,
Evan