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authorSteven Rostedt <srostedt@redhat.com>2010-05-21 11:49:57 -0400
committerSteven Rostedt <rostedt@goodmis.org>2010-05-21 11:49:57 -0400
commitff5f149b6aec8edbfa3698721667acd043009a33 (patch)
treed052553eb296dfee3f01b1cb2b717cb7ccf3127a /arch/x86/include/asm/arch_hweight.h
parentf0218b3e9974f06014b61be8987159f4a20e011e (diff)
parent580d607cd666dfabfc1c7b0fb08c8ac690c7c87f (diff)
Merge branch 'perf/core' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip into trace/tip/tracing/core-7
Conflicts: include/linux/ftrace_event.h include/trace/ftrace.h kernel/trace/trace_event_perf.c kernel/trace/trace_kprobe.c kernel/trace/trace_syscalls.c Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Diffstat (limited to 'arch/x86/include/asm/arch_hweight.h')
-rw-r--r--arch/x86/include/asm/arch_hweight.h61
1 files changed, 61 insertions, 0 deletions
diff --git a/arch/x86/include/asm/arch_hweight.h b/arch/x86/include/asm/arch_hweight.h
new file mode 100644
index 000000000000..9686c3d9ff73
--- /dev/null
+++ b/arch/x86/include/asm/arch_hweight.h
@@ -0,0 +1,61 @@
1#ifndef _ASM_X86_HWEIGHT_H
2#define _ASM_X86_HWEIGHT_H
3
4#ifdef CONFIG_64BIT
5/* popcnt %edi, %eax -- redundant REX prefix for alignment */
6#define POPCNT32 ".byte 0xf3,0x40,0x0f,0xb8,0xc7"
7/* popcnt %rdi, %rax */
8#define POPCNT64 ".byte 0xf3,0x48,0x0f,0xb8,0xc7"
9#define REG_IN "D"
10#define REG_OUT "a"
11#else
12/* popcnt %eax, %eax */
13#define POPCNT32 ".byte 0xf3,0x0f,0xb8,0xc0"
14#define REG_IN "a"
15#define REG_OUT "a"
16#endif
17
18/*
19 * __sw_hweightXX are called from within the alternatives below
20 * and callee-clobbered registers need to be taken care of. See
21 * ARCH_HWEIGHT_CFLAGS in <arch/x86/Kconfig> for the respective
22 * compiler switches.
23 */
24static inline unsigned int __arch_hweight32(unsigned int w)
25{
26 unsigned int res = 0;
27
28 asm (ALTERNATIVE("call __sw_hweight32", POPCNT32, X86_FEATURE_POPCNT)
29 : "="REG_OUT (res)
30 : REG_IN (w));
31
32 return res;
33}
34
35static inline unsigned int __arch_hweight16(unsigned int w)
36{
37 return __arch_hweight32(w & 0xffff);
38}
39
40static inline unsigned int __arch_hweight8(unsigned int w)
41{
42 return __arch_hweight32(w & 0xff);
43}
44
45static inline unsigned long __arch_hweight64(__u64 w)
46{
47 unsigned long res = 0;
48
49#ifdef CONFIG_X86_32
50 return __arch_hweight32((u32)w) +
51 __arch_hweight32((u32)(w >> 32));
52#else
53 asm (ALTERNATIVE("call __sw_hweight64", POPCNT64, X86_FEATURE_POPCNT)
54 : "="REG_OUT (res)
55 : REG_IN (w));
56#endif /* CONFIG_X86_32 */
57
58 return res;
59}
60
61#endif