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#if defined(__GNUC__) && (__GNUC__ >= 5)
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#include "uint32.h"
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int imult32( int32 a, int32 b, int32* c) { return !__builtin_mul_overflow(a,b,c); }
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#else
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#include "safemult.h"
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int imult32(int32 a,int32 b,int32* c) {
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int64 x=(int64)a*b;
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if ((int32)x != x) return 0;
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*c=x;
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return 1;
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}
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#endif
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#ifdef UNITTEST
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#include <assert.h>
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int main() {
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int32 b;
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assert(imult32(0x40000000,2,&b)==0);
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assert(imult32(-0x40000000,2,&b)==1 && b==-0x80000000ll);
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assert(imult32(0x3fffffff,2,&b)==1 && b==0x7ffffffe);
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return 0;
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}
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#endif
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