+ union {
+ U32 u;
+ float f;
+ } v;
+ v.f = f;
+
+ U16 result = (v.u>>16)&0x8000; //sign
+ int exp = ((v.u>>23)&0xff)-0x7f+0x10;
+ U16 m = (v.u>>13)&0x3ff;
+ //fprintf(stderr, "%f: %04x sign, %d exp, %04x mantissa\n", f, result, exp, m);
+ if(exp<-10) {
+ // underflow (clamp to 0.0)
+ exp = 0;
+ m = 0;
+ } else if(exp<0) {
+ // partial underflow- strip some bits
+ m = (m|0x400)>>-exp;