Mike Frysinger
b2ea48df92
The cgen code uses DI as int64_t and UDI as uint64_t. The DI macros are used to construct 64-bit values from 32-bit values (for the low and high parts). The MAKEDI macro casts the high 32-bit value to a signed 32-bit value before shifting. If this created a negative value, this would be undefined behavior according to the C standard. All we care about is shifting the 32-bits as they are to the high 32-bits, not caring about sign extension (since there's nothing left to shift into), and the low 32-bits being empty. This is what we get from shifting an unsigned value, so cast it to unsigned 32-bit to avoid undefined behavior. While we're here, change the SETLODI macro to truncate the lower value to 32-bits before we set it. If it was passing in a 64-bit value, those high bits would get included too, and that's not what we want. Similarly, tweak the SETHIDI macro to cast the value to an unsigned 64-bit instead of a signed 64-bit. If the value was only 32-bits, the behavior would be the same. If it happened to be signed 64-bit, it would trigger the undefined behavior too.
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