swap: Get rid of undefined behavior in swapf and swapd
This isn't well-defined in C++.
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@ -25,6 +25,8 @@
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#include <sys/endian.h>
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#endif
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#include <cstring>
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#include "common/common_types.h"
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// GCC 4.6+
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@ -89,27 +91,29 @@ inline u64 swap64(u64 data) {return ((u64)swap32(data) << 32) | swap32(data >> 3
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#endif
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inline float swapf(float f) {
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union {
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float f;
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unsigned int u32;
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} dat1, dat2;
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static_assert(sizeof(u32) == sizeof(float),
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"float must be the same size as uint32_t.");
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dat1.f = f;
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dat2.u32 = swap32(dat1.u32);
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u32 value;
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std::memcpy(&value, &f, sizeof(u32));
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return dat2.f;
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value = swap32(value);
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std::memcpy(&f, &value, sizeof(u32));
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return f;
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}
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inline double swapd(double f) {
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union {
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double f;
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unsigned long long u64;
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} dat1, dat2;
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static_assert(sizeof(u64) == sizeof(double),
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"double must be the same size as uint64_t.");
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dat1.f = f;
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dat2.u64 = swap64(dat1.u64);
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u64 value;
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std::memcpy(&value, &f, sizeof(u64));
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return dat2.f;
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value = swap64(value);
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std::memcpy(&f, &value, sizeof(u64));
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return f;
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}
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} // Namespace Common
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