Re: [PATCH v2 5/7] arm/pmu: Fix inline assembly for Clang

Andrew Jones
2020-10-01T09:14:48Z

On Thu, Oct 01, 2020 at 11:12:43AM +0200, Andrew Jones wrote:
> On Thu, Oct 01, 2020 at 09:22:32AM +0200, Thomas Huth wrote:
> > Clang complains here:
> >
> > arm/pmu.c:201:16: error: value size does not match register size specified by
> > the constraint and modifier [-Werror,-Wasm-operand-widths]
> > : [pmcr] "r" (pmcr)
> > ^
> > arm/pmu.c:194:18: note: use constraint modifier "w"
> > " msr pmcr_el0, %[pmcr]\n"
> > ^~~~~~~
> > %w[pmcr]
> > arm/pmu.c:200:17: error: value size does not match register size specified by
> > the constraint and modifier [-Werror,-Wasm-operand-widths]
> > : [loop] "+r" (loop)
> > ^
> > arm/pmu.c:196:11: note: use constraint modifier "w"
> > "1: subs %[loop], %[loop], #1\n"
> > ^~~~~~~
> > %w[loop]
> > arm/pmu.c:200:17: error: value size does not match register size specified by
> > the constraint and modifier [-Werror,-Wasm-operand-widths]
> > : [loop] "+r" (loop)
> > ^
> > arm/pmu.c:196:20: note: use constraint modifier "w"
> > "1: subs %[loop], %[loop], #1\n"
> > ^~~~~~~
> > %w[loop]
> > arm/pmu.c:284:35: error: value size does not match register size specified
> > by the constraint and modifier [-Werror,-Wasm-operand-widths]
> > : [addr] "r" (addr), [pmcr] "r" (pmcr), [loop] "r" (loop)
> > ^
> > arm/pmu.c:274:28: note: use constraint modifier "w"
> > " msr pmcr_el0, %[pmcr]\n"
> > ^~~~~~~
> > %w[pmcr]
> > arm/pmu.c:284:54: error: value size does not match register size specified
> > by the constraint and modifier [-Werror,-Wasm-operand-widths]
> > : [addr] "r" (addr), [pmcr] "r" (pmcr), [loop] "r" (loop)
> > ^
> > arm/pmu.c:276:23: note: use constraint modifier "w"
> > " mov x10, %[loop]\n"
> > ^~~~~~~
> > %w[loop]
> >
> > pmcr should be 64-bit since it is a sysreg, but for loop we can use the
> > "w" modifier.
> >
> > Suggested-by: Drew Jones <drjones@redhat.com>

Not a huge deal, but I use my official first name 'Andrew' on my tags.
I know, I like confusing people by flipping back and forth between
Andrew and Drew...

Thanks,
drew a.k.a Andrew

> > Signed-off-by: Thomas Huth <thuth@redhat.com>
> > ---
> > arm/pmu.c | 10 ++++++----
> > 1 file changed, 6 insertions(+), 4 deletions(-)
> >
>
> Reviewed-by: Andrew Jones <drjones@redhat.com>
> Tested-by: Andrew Jones <drjones@redhat.com>