Re: [PATCH 02/25] MPILIB: Provide count_leading/trailing_zeros() based on arch functions
O On Thu, Sep 13, 2012 at 8:14 AM, James Morris wrote: > On Mon, 10 Sep 2012, Kasatkin, Dmitry wrote: > >> > Signed-off-by: David Howells >> > Cc: David S. Miller >> > Cc: Dmitry Kasatkin >> > Cc: Arnd Bergmann >> >> Hi James, >> >> Can you please apply this? > > Could you send me this and any other outstanding changes as patches > against my -next branch, tested and signed-off ? > > Or, perhaps Mimi could do that as maintainer of the integrity subsystem. > > Ok. let's do it with other collection of patches... > - James > -- > James Morris > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 02/25] MPILIB: Provide count_leading/trailing_zeros() based on arch functions
On Mon, 10 Sep 2012, Kasatkin, Dmitry wrote: > > Signed-off-by: David Howells > > Cc: David S. Miller > > Cc: Dmitry Kasatkin > > Cc: Arnd Bergmann > > Hi James, > > Can you please apply this? Could you send me this and any other outstanding changes as patches against my -next branch, tested and signed-off ? Or, perhaps Mimi could do that as maintainer of the integrity subsystem. - James -- James Morris -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 02/25] MPILIB: Provide count_leading/trailing_zeros() based on arch functions
On Thu, Aug 16, 2012 at 4:34 AM, David Howells wrote:
> Provide count_leading/trailing_zeros() macros based on extant arch bit
> scanning
> functions rather than reimplementing from scratch in MPILIB.
>
> Whilst we're at it, turn count_foo_zeros(n, x) into n = count_foo_zeros(x).
>
> Also move the definition to asm-generic as other people may be interested in
> using it.
>
> Signed-off-by: David Howells
> Cc: David S. Miller
> Cc: Dmitry Kasatkin
> Cc: Arnd Bergmann
Hi James,
Can you please apply this?
Acked-by: Dmitry Kasatkin
> ---
>
> include/asm-generic/bitops/count_zeros.h | 57
> lib/mpi/longlong.h | 138
> --
> lib/mpi/mpi-bit.c|2
> lib/mpi/mpi-pow.c|4 -
> 4 files changed, 62 insertions(+), 139 deletions(-)
> create mode 100644 include/asm-generic/bitops/count_zeros.h
>
>
> diff --git a/include/asm-generic/bitops/count_zeros.h
> b/include/asm-generic/bitops/count_zeros.h
> new file mode 100644
> index 000..97520d2
> --- /dev/null
> +++ b/include/asm-generic/bitops/count_zeros.h
> @@ -0,0 +1,57 @@
> +/* Count leading and trailing zeros functions
> + *
> + * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
> + * Written by David Howells (dhowe...@redhat.com)
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public Licence
> + * as published by the Free Software Foundation; either version
> + * 2 of the Licence, or (at your option) any later version.
> + */
> +
> +#ifndef _ASM_GENERIC_BITOPS_COUNT_ZEROS_H_
> +#define _ASM_GENERIC_BITOPS_COUNT_ZEROS_H_
> +
> +#include
> +
> +/**
> + * count_leading_zeros - Count the number of zeros from the MSB back
> + * @x: The value
> + *
> + * Count the number of leading zeros from the MSB going towards the LSB in
> @x.
> + *
> + * If the MSB of @x is set, the result is 0.
> + * If only the LSB of @x is set, then the result is BITS_PER_LONG-1.
> + * If @x is 0 then the result is COUNT_LEADING_ZEROS_0.
> + */
> +static inline int count_leading_zeros(unsigned long x)
> +{
> + if (sizeof(x) == 4)
> + return BITS_PER_LONG - fls(x);
> + else
> + return BITS_PER_LONG - fls64(x);
> +}
> +
> +#define COUNT_LEADING_ZEROS_0 BITS_PER_LONG
> +
> +/**
> + * count_trailing_zeros - Count the number of zeros from the LSB forwards
> + * @x: The value
> + *
> + * Count the number of trailing zeros from the LSB going towards the MSB in
> @x.
> + *
> + * If the LSB of @x is set, the result is 0.
> + * If only the MSB of @x is set, then the result is BITS_PER_LONG-1.
> + * If @x is 0 then the result is COUNT_TRAILING_ZEROS_0.
> + */
> +static inline int count_trailing_zeros(unsigned long x)
> +{
> +#define COUNT_TRAILING_ZEROS_0 (-1)
> +
> + if (sizeof(x) == 4)
> + return ffs(x);
> + else
> + return (x != 0) ? __ffs(x) : COUNT_TRAILING_ZEROS_0;
> +}
> +
> +#endif /* _ASM_GENERIC_BITOPS_COUNT_ZEROS_H_ */
> diff --git a/lib/mpi/longlong.h b/lib/mpi/longlong.h
> index 29f9862..678ce4f 100644
> --- a/lib/mpi/longlong.h
> +++ b/lib/mpi/longlong.h
> @@ -19,6 +19,8 @@
> * the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
> * MA 02111-1307, USA. */
>
> +#include
> +
> /* You have to define the following before including this file:
> *
> * UWtype -- An unsigned type, default type for operations (typically a
> "word")
> @@ -146,12 +148,6 @@ do { \
> : "1" ((USItype)(n1)), \
> "r" ((USItype)(n0)), \
> "r" ((USItype)(d)))
> -
> -#define count_leading_zeros(count, x) \
> - __asm__ ("clz %0,%1" \
> - : "=r" ((USItype)(count)) \
> - : "r" ((USItype)(x)))
> -#define COUNT_LEADING_ZEROS_0 32
> #endif /* __a29k__ */
>
> #if defined(__alpha) && W_TYPE_SIZE == 64
> @@ -298,11 +294,6 @@ extern UDItype __udiv_qrnnd();
> : "1" ((USItype)(nh)), \
> "0" ((USItype)(nl)), \
> "g" ((USItype)(d)))
> -#define count_leading_zeros(count, x) \
> - __asm__ ("bsch/1 %1,%0" \
> - : "=g" (count) \
> - : "g" ((USItype)(x)), \
> -"0" ((USItype)0))
> #endif
>
> /***
> @@ -354,27 +345,6 @@ do { USItype __r; \
> } while (0)
> extern USItype __udiv_qrnnd();
> #endif /* LONGLONG_STANDALONE */
> -#define count_leading_zeros(count, x) \
> -do { \
> - USItype __tmp; \
> - __asm__ ( \
> - "ldi 1,%0\n" \
> - "extru,=%1,15,16,%%r0 ; Bits 31..16 zero?\n" \
> - "extru,tr %1,15,16,%1; No. Shift down, skip add.\n" \
> - "ldo16(%0),%0 ; Yes. Perform add.\n" \
> - "extru,=%1,23,8,%%r0 ; Bits 15..8 zero?\n" \
> - "extru,tr %1,23,8,%1 ; No. Shift down, skip add.\n" \
> - "ldo8(%0),%0 ; Yes. Perfor
[PATCH 02/25] MPILIB: Provide count_leading/trailing_zeros() based on arch functions
Provide count_leading/trailing_zeros() macros based on extant arch bit scanning
functions rather than reimplementing from scratch in MPILIB.
Whilst we're at it, turn count_foo_zeros(n, x) into n = count_foo_zeros(x).
Also move the definition to asm-generic as other people may be interested in
using it.
Signed-off-by: David Howells
Cc: David S. Miller
Cc: Dmitry Kasatkin
Cc: Arnd Bergmann
---
include/asm-generic/bitops/count_zeros.h | 57
lib/mpi/longlong.h | 138 --
lib/mpi/mpi-bit.c|2
lib/mpi/mpi-pow.c|4 -
4 files changed, 62 insertions(+), 139 deletions(-)
create mode 100644 include/asm-generic/bitops/count_zeros.h
diff --git a/include/asm-generic/bitops/count_zeros.h
b/include/asm-generic/bitops/count_zeros.h
new file mode 100644
index 000..97520d2
--- /dev/null
+++ b/include/asm-generic/bitops/count_zeros.h
@@ -0,0 +1,57 @@
+/* Count leading and trailing zeros functions
+ *
+ * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowe...@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+
+#ifndef _ASM_GENERIC_BITOPS_COUNT_ZEROS_H_
+#define _ASM_GENERIC_BITOPS_COUNT_ZEROS_H_
+
+#include
+
+/**
+ * count_leading_zeros - Count the number of zeros from the MSB back
+ * @x: The value
+ *
+ * Count the number of leading zeros from the MSB going towards the LSB in @x.
+ *
+ * If the MSB of @x is set, the result is 0.
+ * If only the LSB of @x is set, then the result is BITS_PER_LONG-1.
+ * If @x is 0 then the result is COUNT_LEADING_ZEROS_0.
+ */
+static inline int count_leading_zeros(unsigned long x)
+{
+ if (sizeof(x) == 4)
+ return BITS_PER_LONG - fls(x);
+ else
+ return BITS_PER_LONG - fls64(x);
+}
+
+#define COUNT_LEADING_ZEROS_0 BITS_PER_LONG
+
+/**
+ * count_trailing_zeros - Count the number of zeros from the LSB forwards
+ * @x: The value
+ *
+ * Count the number of trailing zeros from the LSB going towards the MSB in @x.
+ *
+ * If the LSB of @x is set, the result is 0.
+ * If only the MSB of @x is set, then the result is BITS_PER_LONG-1.
+ * If @x is 0 then the result is COUNT_TRAILING_ZEROS_0.
+ */
+static inline int count_trailing_zeros(unsigned long x)
+{
+#define COUNT_TRAILING_ZEROS_0 (-1)
+
+ if (sizeof(x) == 4)
+ return ffs(x);
+ else
+ return (x != 0) ? __ffs(x) : COUNT_TRAILING_ZEROS_0;
+}
+
+#endif /* _ASM_GENERIC_BITOPS_COUNT_ZEROS_H_ */
diff --git a/lib/mpi/longlong.h b/lib/mpi/longlong.h
index 29f9862..678ce4f 100644
--- a/lib/mpi/longlong.h
+++ b/lib/mpi/longlong.h
@@ -19,6 +19,8 @@
* the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
* MA 02111-1307, USA. */
+#include
+
/* You have to define the following before including this file:
*
* UWtype -- An unsigned type, default type for operations (typically a "word")
@@ -146,12 +148,6 @@ do { \
: "1" ((USItype)(n1)), \
"r" ((USItype)(n0)), \
"r" ((USItype)(d)))
-
-#define count_leading_zeros(count, x) \
- __asm__ ("clz %0,%1" \
- : "=r" ((USItype)(count)) \
- : "r" ((USItype)(x)))
-#define COUNT_LEADING_ZEROS_0 32
#endif /* __a29k__ */
#if defined(__alpha) && W_TYPE_SIZE == 64
@@ -298,11 +294,6 @@ extern UDItype __udiv_qrnnd();
: "1" ((USItype)(nh)), \
"0" ((USItype)(nl)), \
"g" ((USItype)(d)))
-#define count_leading_zeros(count, x) \
- __asm__ ("bsch/1 %1,%0" \
- : "=g" (count) \
- : "g" ((USItype)(x)), \
-"0" ((USItype)0))
#endif
/***
@@ -354,27 +345,6 @@ do { USItype __r; \
} while (0)
extern USItype __udiv_qrnnd();
#endif /* LONGLONG_STANDALONE */
-#define count_leading_zeros(count, x) \
-do { \
- USItype __tmp; \
- __asm__ ( \
- "ldi 1,%0\n" \
- "extru,=%1,15,16,%%r0 ; Bits 31..16 zero?\n" \
- "extru,tr %1,15,16,%1; No. Shift down, skip add.\n" \
- "ldo16(%0),%0 ; Yes. Perform add.\n" \
- "extru,=%1,23,8,%%r0 ; Bits 15..8 zero?\n" \
- "extru,tr %1,23,8,%1 ; No. Shift down, skip add.\n" \
- "ldo8(%0),%0 ; Yes. Perform add.\n" \
- "extru,=%1,27,4,%%r0 ; Bits 7..4 zero?\n" \
- "extru,tr %1,27,4,%1 ; No. Shift down, skip add.\n" \
- "ldo4(%0),%0 ; Yes. Perform add.\n" \
- "extru,=%1,29,2,%%r0 ; Bits 3..2 zero?\n" \
- "extru,tr %1,29,2,%1 ; No. Shift down, skip add.\n" \
- "ldo2(%0),%0 ; Yes. Perform a
