xtensa: Make use of BALL/BNALL instructions
In Xtensa ISA, there is no single machine instruction that calculates unary
bitwise negation, but a few similar fused instructions are exist:
"BALL Ax, Ay, label" // if ((~Ax & Ay) == 0) goto label;
"BNALL Ax, Ay, label" // if ((~Ax & Ay) != 0) goto label;
These instructions have never been emitted before, but it seems no reason not
to make use of them.
gcc/ChangeLog:
* config/xtensa/xtensa.md (*masktrue_bitcmpl): New insn pattern.
gcc/testsuite/ChangeLog:
* gcc.target/xtensa/BALL-BNALL.c: New.