Unused variable might be an error

[camel-cdr]

When cleaning up unused variable warnings, I noticed a few unused variables that might be an error:

veclibm/include/rvvlm_tanD.inc.h

Lines 63 to 71 in 0a6c0c0

	VFLOAT A = __riscv_vfmul(n_flt, PIBY2_MID, vlen);
	VFLOAT a = __riscv_vfmsub(n_flt, PIBY2_MID, A, vlen);
	// A + a is n * piby2_mid exactly
	VFLOAT S = __riscv_vfsub(r_hi, A, vlen);
	VFLOAT s = __riscv_vfsub(r_hi, S, vlen);
	s = __riscv_vfsub(s, A, vlen);
	s = __riscv_vfnmsac(s, PIBY2_LO, n_flt, vlen);
	r = __riscv_vmerge(r, S, r_small, vlen);
	r_delta = __riscv_vmerge(r_delta, s, r_small, vlen);

veclibm/include/rvvlm_sinandcosD.inc.h

Lines 64 to 72 in 0a6c0c0

	VFLOAT A = __riscv_vfmul(n_flt, PIBY2_MID, vlen);
	VFLOAT a = __riscv_vfmsub(n_flt, PIBY2_MID, A, vlen);
	// A + a is n * piby2_mid exactly
	VFLOAT S = __riscv_vfsub(r_hi, A, vlen);
	VFLOAT s = __riscv_vfsub(r_hi, S, vlen);
	s = __riscv_vfsub(s, A, vlen);
	s = __riscv_vfnmsac(s, PIBY2_LO, n_flt, vlen);
	r = __riscv_vmerge(r, S, r_small, vlen);
	r_delta = __riscv_vmerge(r_delta, s, r_small, vlen);

veclibm/include/rvvlm_sincosD.inc.h

Lines 75 to 83 in 0a6c0c0

	VFLOAT A = __riscv_vfmul(n_flt, PIBY2_MID, vlen);
	VFLOAT a = __riscv_vfmsub(n_flt, PIBY2_MID, A, vlen);
	// A + a is n * piby2_mid exactly
	VFLOAT S = __riscv_vfsub(r_hi, A, vlen);
	VFLOAT s = __riscv_vfsub(r_hi, S, vlen);
	s = __riscv_vfsub(s, A, vlen);
	s = __riscv_vfnmsac(s, PIBY2_LO, n_flt, vlen);
	r = __riscv_vmerge(r, S, r_small, vlen);
	r_delta = __riscv_vmerge(r_delta, s, r_small, vlen);

The comments seem to imply that a should be used, but it isn't. I don't know enough about the implementation to tell if this is an error, or just an unused variable that can be removed.

[PingTakPeterTang]

Thanks for spotting this. There is actually a bug here. Apparently tests did not exercise this branch of the code: where input argument is not too large but very close to integer multiples of pi. I will fix the code and also add some test infra to test special arguments.