When a binary (in)equality comparison has a constant left operand,
the tgt-vvp code generator swaps the left and right operands to
allow the cmpi instruction to be used. The code for swapping the
operands was incorrect.
Before this patch, only literals on the right side of a < compare
(or left side of a > compare) would be blended into a %cmpi instruction.
This patch broadends the cases where the %cmpi can be used.
When generating code for a condition expression, i.e. directly
before a %jmp/X statement, try to generate the result into the
flag bit without passing through the vec4 stack. For example, the
%cmpX/X instructions generate results into the flag bits, so it
makes no sense to push these bits into the vec4 stack then pop
them back into the flag bit. So try to handle this case.
Martin Whitaker
Stephen Williams