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eeb20775d2
This will help C++ code that uses exceptions to be tinier. For example, this change shaves away 1000 lines of assembly code from LLVM's libcxx, which is 0.7% of all assembly instructions in the entire library.
17 lines
545 B
C
17 lines
545 B
C
#ifndef COSMOPOLITAN_LIBC_NEXGEN32E_BSR_H_
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#define COSMOPOLITAN_LIBC_NEXGEN32E_BSR_H_
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COSMOPOLITAN_C_START_
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libcesque int _bsr(int) pureconst;
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libcesque int _bsrl(long) pureconst;
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libcesque int _bsrll(long long) pureconst;
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#if defined(__GNUC__) && !defined(__STRICT_ANSI__)
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#define _bsr(x) (__builtin_clz(x) ^ (sizeof(int) * 8 - 1))
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#define _bsrl(x) (__builtin_clzl(x) ^ (sizeof(long) * 8 - 1))
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#define _bsrll(x) (__builtin_clzll(x) ^ (sizeof(long long) * 8 - 1))
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#endif
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COSMOPOLITAN_C_END_
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#endif /* COSMOPOLITAN_LIBC_NEXGEN32E_BSR_H_ */
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