C: avoid undefined behavior for bit shifts >= 32 - #54
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The C standard says, for bit shifts: > If the value of the right operand [...] is greater than or equal to the width of the promoted left operand, the behavior is undefined. But in our generated C code, we allow shifts for the full value of RegX. Do the same thing the kernel does: mask it with & 31 to avoid any undefined behavior.
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The C standard says, for bit shifts:
But in our generated C code, we allow shifts for the full value of RegX.
Do the same thing the kernel does: mask it with & 31 to avoid any undefined behavior.