I have the following code line:
ciirsL.B0 = p.B0H << 8 + p.B0L >> 24;
---^-int----------^-int---------------^-unsigned
The structures assign the types as shown above.
The >>24 incorrectly is ASHR instead of SHR for an unsigned in the compiled code.
Doesn't work either:
ciirsL.B0 = p.B0H << 8 + (unsigned)p.B0L >> 24;
Does work:
ciirsL.B0 = p.B0H << 8 + (p.B0L >> 24);
Is this typical for C and I need to recognize this from now on? Is it typical to just enclose everything in C? I would have thought the >> had precedence and been a SHR instead. Lucky for me a caught this very quickly when it didn't work.
Question on XC and data type precedence
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bearcat
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richard
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Based on the associativity and precedence of the C / XC operators this is evaluated as:
In C / XC if x is of type int then so is x << y. Therefore (p.B0H << (8 + p.B0L)) is of type int and so an arithmetic right shift is used for the shift by 24.
Code: Select all
ciirsL[i].B0 = (p[i].B0H << (8 + p[i].B0L)) >> 24;