// PR rtl-optimization/40924 // { dg-do run } extern "C" void abort (void); #define MAY_ALIAS __attribute__((__may_alias__)) typedef struct { float v[2]; } floata; typedef struct { int v[2]; } inta; typedef unsigned int uint MAY_ALIAS; typedef signed int sint MAY_ALIAS; typedef float flt MAY_ALIAS; static inline unsigned short less_than (inta a, inta b) { unsigned short r = 0; const uint *p1 = (const uint *) &a; const uint *p2 = (const uint *) &b; for (int i=0; i < 2; i++) if (p1[i] < p2[i]) r |= (1 << i); return r; } static inline inta multiply (inta b, inta c) { inta r; sint *p3 = (sint *) &c; for (int i=0; i < 2; i++) r.v[i] = (int) (b.v[i] * p3[i] & 0xFFFFFFFF); return r; } static inline floata gather (inta indexes, const void *baseAddr) { floata r; sint *idx = (sint *) &indexes; flt *src = (flt *) baseAddr; for (int i=0; i < 2; i++) r.v[i] = *(src + idx[i]); return r; } static inline inta add (const inta &b, const inta &c) { inta result; sint *r = (sint *) &result; for (int i=0; i < 2; i++) r[i] = b.v[i] + c.v[i]; return result; } struct uintv { inta data; inline uintv () { data.v[0] = 0; data.v[1] = 1; } inline uintv (unsigned int a) { for (int i=0; i < 2; i++) *(uint *) &data.v[i] = a; } inline uintv (inta x) : data (x) {} inline uintv operator* (const uintv &x) const { return multiply (data, x.data); } inline uintv operator+ (const uintv &x) const { return uintv (add (data, x.data)); } inline unsigned short operator< (const uintv &x) const { return less_than (data, x.data); } }; struct floatv { floata data; explicit inline floatv (const uintv &x) { uint *p2 = (uint *) &x.data; for (int i=0; i < 2; i++) data.v[i] = p2[i]; } inline floatv (const float *array, const uintv &indexes) { const uintv &offsets = indexes * uintv (1); data = gather (offsets.data, array); } unsigned short operator== (const floatv &x) const { unsigned short r = 0; for (int i=0; i < 2; i++) if (data.v[i] == x.data.v[i]) r |= (1 << i); return r; } }; int main () { const float array[2] = { 2, 3 }; for (uintv i; (i < 2) == 3; i = i + 2) { const floatv ii (i + 2); floatv a (array, i); if ((a == ii) != 3) abort (); } }