2013-05-05 22:08:28

by Helge Deller

Subject: [PATCH] MPILIB: disable usage of floating point registers on parisc

The umul_ppmm() macro for parisc uses the xmpyu assembler statement
which does calculation via a floating point register.

But usage of floating point registers inside the Linux kernel are not
allowed and gcc will stop compilation due to the -mdisable-fpregs
compiler option.

Fix this by disabling the umul_ppmm() and udiv_qrnnd() macros. The
mpilib will then use the generic built-in implementations instead.

Signed-off-by: Helge Deller <[email protected]>

diff --git a/lib/mpi/longlong.h b/lib/mpi/longlong.h
index 095ab15..d411355 100644
--- a/lib/mpi/longlong.h
+++ b/lib/mpi/longlong.h
@@ -318,7 +318,8 @@ extern UDItype __udiv_qrnnd();
"rM" ((USItype)(bh)), \
"rM" ((USItype)(al)), \
"rM" ((USItype)(bl)))
-#if defined(_PA_RISC1_1)
+#if 0 && defined(_PA_RISC1_1)
+/* xmpyu uses floating point register which is not allowed in Linux kernel. */
#define umul_ppmm(wh, wl, u, v) \
do { \
union {UDItype __ll; \
@@ -337,7 +338,7 @@ do { \
#define UMUL_TIME 40
#define UDIV_TIME 80
#endif
-#ifndef LONGLONG_STANDALONE
+#if 0 /* #ifndef LONGLONG_STANDALONE */
#define udiv_qrnnd(q, r, n1, n0, d) \
do { USItype __r; \
(q) = __udiv_qrnnd(&__r, (n1), (n0), (d)); \

2013-05-31 14:43:27

by Dmitry Kasatkin

Subject: Re: [PATCH] MPILIB: disable usage of floating point registers on parisc

Sorry. I am not at @intel.com any more. Did not see it.
Will handle.

- Dmitry


On Mon, May 6, 2013 at 1:08 AM, Helge Deller <[email protected]> wrote:
> The umul_ppmm() macro for parisc uses the xmpyu assembler statement
> which does calculation via a floating point register.
>
> But usage of floating point registers inside the Linux kernel are not
> allowed and gcc will stop compilation due to the -mdisable-fpregs
> compiler option.
>
> Fix this by disabling the umul_ppmm() and udiv_qrnnd() macros. The
> mpilib will then use the generic built-in implementations instead.
>
> Signed-off-by: Helge Deller <[email protected]>
>
> diff --git a/lib/mpi/longlong.h b/lib/mpi/longlong.h
> index 095ab15..d411355 100644
> --- a/lib/mpi/longlong.h
> +++ b/lib/mpi/longlong.h
> @@ -318,7 +318,8 @@ extern UDItype __udiv_qrnnd();
> "rM" ((USItype)(bh)), \
> "rM" ((USItype)(al)), \
> "rM" ((USItype)(bl)))
> -#if defined(_PA_RISC1_1)
> +#if 0 && defined(_PA_RISC1_1)
> +/* xmpyu uses floating point register which is not allowed in Linux kernel. */
> #define umul_ppmm(wh, wl, u, v) \
> do { \
> union {UDItype __ll; \
> @@ -337,7 +338,7 @@ do { \
> #define UMUL_TIME 40
> #define UDIV_TIME 80
> #endif
> -#ifndef LONGLONG_STANDALONE
> +#if 0 /* #ifndef LONGLONG_STANDALONE */
> #define udiv_qrnnd(q, r, n1, n0, d) \
> do { USItype __r; \
> (q) = __udiv_qrnnd(&__r, (n1), (n0), (d)); \
> --
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