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d94e6fe0fd
Use the compiler intrinsic __builtin_popcount. Change-Id: I58286fbcf66d1068390ea9caff2f98b8fe244c2d Reviewed-on: https://go-review.googlesource.com/16831 Reviewed-by: Andrew Gerrand <adg@golang.org>
20 lines
529 B
C
20 lines
529 B
C
// Copyright 2015 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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// +build gccgo
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#include <errno.h>
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#include <stdint.h>
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#include <unistd.h>
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#define _STRINGIFY2_(x) #x
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#define _STRINGIFY_(x) _STRINGIFY2_(x)
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#define GOSYM_PREFIX _STRINGIFY_(__USER_LABEL_PREFIX__)
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extern intptr_t popcount(uintptr_t x) __asm__(GOSYM_PREFIX GOPKGPATH ".popcount");
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intptr_t popcount(uintptr_t x) {
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return __builtin_popcountl((unsigned long)(x));
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}
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