ppc64 JIT: fix float <=/>= with NaN operands - #413
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OP_LEF/OP_GEF mapped to a single CR0 test (branch if !GT / !LT). PPC FCMPU sets only CR0[SO] when an operand is NaN, leaving LT/GT/EQ clear, so those conditions wrongly took the branch on unordered operands - diverging from the interpreter and aarch64 (where NaN <= / >= is false). Fold the unordered bit into the tested bit via cror before the branch (GT |= SO for <=, LT |= SO for >=) so a NaN operand does not branch. Ordered comparisons and the other four float compares are unaffected; the integer LE/GE paths are untouched. Verified with a differential harness (JIT vs interpreter): NaN <= / >= 1.0 returned 1 on the JIT before and 0 after, matching the interpreter.
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The PPC64 JIT compiled
OP_LEF/OP_GEFas a single CR0 test, butfcmpuonly sets the SO bit on a NaN operand, soNaN <= xandNaN >= xwrongly took the branch. Now folds the unordered bit in viacrorso it matches the interpreter and the aarch64 JIT (both false). Other float compares and the integer paths are unchanged. Verified with a JIT-vs-interpreter diff:NaN <= 1.0returned 1 before, 0 after.