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Subject[70/90] sparc: Use hweight64() in popc emulation.
3.0-stable review patch.  If anyone has any objections, please let us know.

------------------

From: "David S. Miller" <davem@davemloft.net>

[ Upstream commit d600cbed0fe8fceec04500824f638dfe4996c653 ]

Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---
arch/sparc/kernel/unaligned_64.c | 15 ++++-----------
1 file changed, 4 insertions(+), 11 deletions(-)
--- a/arch/sparc/kernel/unaligned_64.c
+++ b/arch/sparc/kernel/unaligned_64.c
@@ -22,6 +22,7 @@
#include <linux/bitops.h>
#include <linux/perf_event.h>
#include <linux/ratelimit.h>
+#include <linux/bitops.h>
#include <asm/fpumacro.h>

enum direction {
@@ -373,16 +374,11 @@ asmlinkage void kernel_unaligned_trap(st
}
}

-static char popc_helper[] = {
-0, 1, 1, 2, 1, 2, 2, 3,
-1, 2, 2, 3, 2, 3, 3, 4,
-};
-
int handle_popc(u32 insn, struct pt_regs *regs)
{
- u64 value;
- int ret, i, rd = ((insn >> 25) & 0x1f);
int from_kernel = (regs->tstate & TSTATE_PRIV) != 0;
+ int ret, rd = ((insn >> 25) & 0x1f);
+ u64 value;

perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 1, 0, regs, 0);
if (insn & 0x2000) {
@@ -392,10 +388,7 @@ int handle_popc(u32 insn, struct pt_regs
maybe_flush_windows(0, insn & 0x1f, rd, from_kernel);
value = fetch_reg(insn & 0x1f, regs);
}
- for (ret = 0, i = 0; i < 16; i++) {
- ret += popc_helper[value & 0xf];
- value >>= 4;
- }
+ ret = hweight64(value);
if (rd < 16) {
if (rd)
regs->u_regs[rd] = ret;



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