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Diffstat (limited to 'src/devices/cpu/rsp/vmuln.h')
-rw-r--r--src/devices/cpu/rsp/vmuln.h55
1 files changed, 0 insertions, 55 deletions
diff --git a/src/devices/cpu/rsp/vmuln.h b/src/devices/cpu/rsp/vmuln.h
deleted file mode 100644
index 07453b631a8..00000000000
--- a/src/devices/cpu/rsp/vmuln.h
+++ /dev/null
@@ -1,55 +0,0 @@
-// license:BSD-3-Clause
-// copyright-holders:Tyler J. Stachecki,Ryan Holtz
-
-inline rsp_vec_t vec_vmadn_vmudn(uint32_t iw, rsp_vec_t vs, rsp_vec_t vt, rsp_vec_t zero, rsp_vec_t *acc_lo, rsp_vec_t *acc_md, rsp_vec_t *acc_hi)
-{
- rsp_vec_t lo = _mm_mullo_epi16(vs, vt);
- rsp_vec_t hi = _mm_mulhi_epu16(vs, vt);
-
- // What we really want to do is unsigned vs * signed vt.
- // However, we have no such instructions to do so.
- //
- // There's a trick to "fix" an unsigned product, though:
- // If vt was negative, take the upper 16-bits of the product
- // and subtract vs.
- rsp_vec_t sign = _mm_srai_epi16(vt, 15);
- vs = _mm_and_si128(vs, sign);
- hi = _mm_sub_epi16(hi, vs);
-
- if (iw & 0x8) // VMADN
- {
- // Tricky part: start accumulating everything.
- // Get/keep the carry as we'll add it in later.
- rsp_vec_t overflow_mask = _mm_adds_epu16(*acc_lo, lo);
- *acc_lo = _mm_add_epi16(*acc_lo, lo);
-
- overflow_mask = _mm_cmpeq_epi16(*acc_lo, overflow_mask);
- overflow_mask = _mm_cmpeq_epi16(overflow_mask, zero);
-
- // This is REALLY clever. Since the product results from
- // two 16-bit components, one positive and one negative,
- // we don't have to worry about carrying the 1 (we can
- // only borrow) past 32-bits. So we can just add it here.
- hi = _mm_sub_epi16(hi, overflow_mask);
-
- // Check for overflow of the upper sum.
- overflow_mask = _mm_adds_epu16(*acc_md, hi);
- *acc_md = _mm_add_epi16(*acc_md, hi);
-
- overflow_mask = _mm_cmpeq_epi16(*acc_md, overflow_mask);
- overflow_mask = _mm_cmpeq_epi16(overflow_mask, zero);
-
- // Finish up the accumulation of the... accumulator.
- *acc_hi = _mm_add_epi16(*acc_hi, _mm_srai_epi16(hi, 15));
- *acc_hi = _mm_sub_epi16(*acc_hi, overflow_mask);
- return uclamp_acc(*acc_lo, *acc_md, *acc_hi, zero);
- }
- else // VMUDN
- {
- *acc_lo = lo;
- *acc_md = hi;
- *acc_hi = _mm_srai_epi16(hi, 15);
-
- return lo;
- }
-}