From: Jacob Lifshay Date: Mon, 16 Oct 2023 03:59:36 +0000 (-0700) Subject: add labels to DIVMOD REGEX log X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=7d981d02022a7286ca1d8b24537b324aeeebcffd;p=openpower-isa.git add labels to DIVMOD REGEX log --- diff --git a/src/openpower/test/bigint/powmod.py b/src/openpower/test/bigint/powmod.py index fab2daa2..76cfb5b4 100644 --- a/src/openpower/test/bigint/powmod.py +++ b/src/openpower/test/bigint/powmod.py @@ -184,7 +184,7 @@ class _DivModRegsRegexLogger: self.__regs = regs if regs is not None else {} self.enabled = enabled - def log(self, locals_, **changes): + def log(self, locals_, label=None, **changes): """ use like so: ``` # create a variable `a`: @@ -252,7 +252,9 @@ class _DivModRegsRegexLogger: value, name, i = value segments.append(f" +{value:08x}") segments.append("\\n") - log("DIVMOD REGEX:", "".join(segments), kind=LogType.OutputMatching) + prefix = "" if label is None else f"At: {label}\n" + log(prefix + "DIVMOD REGEX:", "".join(segments), + kind=LogType.OutputMatching) def python_divmod_shift_sub_algorithm(n, d, width=256, log_regex=False): @@ -380,44 +382,46 @@ class DivModKnuthAlgorithmD: def python(self, n, d, log_regex=False, on_corner_case=lambda desc: None): do_log = _DivModRegsRegexLogger(enabled=log_regex, regs=self.regs).log - do_log(locals(), n=("n_0", self.num_size), d=("d_0", self.denom_size)) + do_log(locals(), "start", + n=("n_0", self.num_size), d=("d_0", self.denom_size)) # switch to names used by Knuth's algorithm D u = list(n) # dividend assert len(u) == self.num_size, "numerator has wrong size" - do_log(locals(), n=None, u=("u", self.num_size)) + do_log(locals(), "u = n", n=None, u=("u", self.num_size)) m = len(u) # length of dividend - do_log(locals(), m="m") + do_log(locals(), "m = len(u)", m="m") v = list(d) # divisor assert len(v) == self.denom_size, "denominator has wrong size" del d # less confusing to debug - do_log(locals(), d=None, v=("v", self.denom_size)) + do_log(locals(), "v = d", d=None, v=("v", self.denom_size)) n = len(v) # length of divisor - do_log(locals(), n="n_scalar") + do_log(locals(), "n = len(v)", n="n_scalar") # allocate outputs/temporaries -- before any normalization so # the outputs/temporaries can be fixed-length in the assembly version. q = [0] * self.q_size # quotient - do_log(locals(), q=("q", self.q_size)) + do_log(locals(), "q = [0...]", q=("q", self.q_size)) vn = [None] * self.vn_size # normalized divisor - do_log(locals(), vn=("vn", self.vn_size)) + do_log(locals(), "vn = [None...]", vn=("vn", self.vn_size)) un = [None] * self.un_size # normalized dividend - do_log(locals(), un=("un", self.un_size)) + do_log(locals(), "un = [None...]", un=("un", self.un_size)) product = [None] * self.product_size - do_log(locals(), product=("product", self.product_size)) + do_log(locals(), "product = [None...]", + product=("product", self.product_size)) # get non-zero length of dividend while m > 0 and u[m - 1] == 0: m -= 1 - do_log(locals()) + do_log(locals(), "get non-zero dividend len") # get non-zero length of divisor while n > 0 and v[n - 1] == 0: n -= 1 - do_log(locals()) + do_log(locals(), "get non-zero divisor len") if n == 0: raise ZeroDivisionError @@ -430,23 +434,25 @@ class DivModKnuthAlgorithmD: if m > self.q_size: t = u[self.q_size] m = self.q_size - do_log(locals(), t="t_single", n=None) - do_log(locals(), m=None) # VL = m, so we don't need it in a GPR + do_log(locals(), "t = u[q_size]", t="t_single", n=None) + # VL = m, so we don't need it in a GPR + do_log(locals(), "VL = m", m=None) for i in reversed(range(m)): q[i], t, _ = divmod2du(u[i], v[0], t) - do_log(locals()) + do_log(locals(), "divide step") r = [0] * self.r_size # remainder r[0] = t - do_log(locals(), t=None, r=("r", self.r_size)) + do_log(locals(), "finished single-word divisor", + t=None, r=("r", self.r_size)) return q, r if m < n: r = [None] * self.r_size # remainder - do_log(locals(), r=("r", self.r_size), m=None, n=None) + do_log(locals(), "m < n", r=("r", self.r_size), m=None, n=None) # dividend < divisor for i in range(self.r_size): r[i] = u[i] - do_log(locals()) + do_log(locals(), "finished m < n") return q, r # Knuth's algorithm D starts here: @@ -456,131 +462,139 @@ class DivModKnuthAlgorithmD: # calculate amount to shift by -- count leading zeros s = 0 index = n - 1 - do_log(locals(), index="index") + do_log(locals(), "index = n - 1", index="index") while (v[index] << s) >> (self.word_size - 1) == 0: s += 1 - do_log(locals(), s="s_scalar", index=None) + do_log(locals(), "s = clz64", s="s_scalar", index=None) if s != 0: on_corner_case("non-zero shift") # vn = v << s t = 0 - do_log(locals(), t="t_for_uv_shift") + do_log(locals(), "vn = v << s: t = 0", t="t_for_uv_shift") for i in range(n): # dsld t |= v[i] << s v[i] = None # mark reg as unused vn[i] = t % 2 ** self.word_size t >>= self.word_size - do_log(locals()) + do_log(locals(), "vn = v << s: step") # un = u << s t = 0 - do_log(locals(), v=None) + do_log(locals(), "un = u << s: t = 0", v=None) for i in range(m): # dsld t |= u[i] << s u[i] = None # mark reg as unused un[i] = t % 2 ** self.word_size t >>= self.word_size - do_log(locals()) + do_log(locals(), "un = u << s: step") index = m - do_log(locals(), index="index") + do_log(locals(), "un = u << s: index = m", index="index") un[index] = t - do_log(locals(), u=None, t=None, index=None) + do_log(locals(), "un = u << s: un[index] = t", + u=None, t=None, index=None) # Step D2 and Step D7: loop for j in range(min(m - n, self.q_size - 1), -1, -1): - do_log(locals(), j="j") + do_log(locals(), "start of j loop", j="j") # Step D3: calculate q̂ index = j + n - do_log(locals(), index="index") + do_log(locals(), "qhat: index = j + n", index="index") qhat_num_hi = un[index] - do_log(locals(), qhat_num_hi="qhat_num_hi") + do_log(locals(), "qhat_num_hi = un[index]", + qhat_num_hi="qhat_num_hi") index = n - 1 - do_log(locals()) + do_log(locals(), "qhat: index = n - 1") qhat_denom = vn[index] - do_log(locals(), qhat_denom="qhat_denom") + do_log(locals(), "qhat_denom = vn[index]", + qhat_denom="qhat_denom") index = j + n - 1 - do_log(locals()) + do_log(locals(), "qhat: index = j + n - 1") qhat, rhat_lo, ov = divmod2du(un[index], qhat_denom, qhat_num_hi) rhat_hi = 0 - do_log(locals(), qhat="qhat", rhat_lo="rhat_lo", rhat_hi="rhat_hi") + do_log(locals(), "qhat: initial divmod2du", + qhat="qhat", rhat_lo="rhat_lo", rhat_hi="rhat_hi") if ov: # division overflows word on_corner_case("qhat overflows word") assert qhat_num_hi == qhat_denom rhat_lo = (qhat * qhat_denom) % 2 ** self.word_size rhat_hi = (qhat * qhat_denom) >> self.word_size - do_log(locals()) + do_log(locals(), "qhat ov: rhat = qhat * qhat_denom") borrow = un[index] < rhat_lo rhat_lo = (un[index] - rhat_lo) % 2 ** self.word_size - do_log(locals()) + do_log(locals(), "qhat ov: un[index] - rhat_lo") rhat_hi = qhat_num_hi - rhat_hi - borrow - do_log(locals(), qhat_num_hi=None, qhat_denom=None) + do_log(locals(), "qhat: after overflow check", + qhat_num_hi=None, qhat_denom=None) while rhat_hi == 0: index = n - 2 - do_log(locals()) + do_log(locals(), "qhat adj loop: index = n - 2") qhat_prod_lo = (qhat * vn[index]) % 2 ** self.word_size - do_log(locals(), qhat_prod_lo="qhat_prod_lo", rhat_hi=None) + do_log(locals(), "qhat adj loop: prod_lo", + qhat_prod_lo="qhat_prod_lo", rhat_hi=None) qhat_prod_hi = (qhat * vn[index]) >> self.word_size - do_log(locals(), qhat_prod_hi="qhat_prod_hi") + do_log(locals(), "qhat adj loop: prod_hi", + qhat_prod_hi="qhat_prod_hi") if qhat_prod_hi < rhat_lo: break index = j + n - 2 - do_log(locals()) + do_log(locals(), "qhat adj loop: index = j + n - 2") if qhat_prod_hi == rhat_lo: if qhat_prod_lo <= un[index]: break on_corner_case("qhat adjustment") - do_log(locals(), index=None, + do_log(locals(), "qhat adj loop: adj needed", index=None, qhat_prod_lo=None, qhat_prod_hi=None) qhat -= 1 - do_log(locals(), index="index") + do_log(locals(), "qhat adj loop: qhat -= 1", index="index") index = n - 1 - do_log(locals()) + do_log(locals(), "qhat adj loop: index = n - 1") carry = (rhat_lo + vn[index]) >= 2 ** self.word_size rhat_lo = (rhat_lo + vn[index]) % 2 ** self.word_size - do_log(locals()) + do_log(locals(), "qhat adj loop: rhat_lo += vn[index]") rhat_hi = carry - do_log(locals(), rhat_hi="rhat_hi") + do_log(locals(), "qhat adj loop: rhat_hi = CA", + rhat_hi="rhat_hi") - do_log(locals(), rhat_lo=None, rhat_hi=None, index=None, - qhat_prod_lo=None, qhat_prod_hi=None) + do_log(locals(), "computed qhat", rhat_lo=None, rhat_hi=None, + index=None, qhat_prod_lo=None, qhat_prod_hi=None) # Step D4: multiply and subtract t = 0 - do_log(locals(), t="t_for_prod") + do_log(locals(), "product: t = 0", t="t_for_prod") for i in range(n): # maddedu t += vn[i] * qhat product[i] = t % 2 ** self.word_size t >>= self.word_size - do_log(locals()) + do_log(locals(), "product: step") index = n - do_log(locals(), index="index") + do_log(locals(), "product: index = n", index="index") product[index] = t - do_log(locals(), t=None, index=None) + do_log(locals(), "product[index] = t", t=None, index=None) t = 1 - do_log(locals()) + do_log(locals(), "subtract: t = 1") sub_len = n + 1 - do_log(locals(), sub_len="sub_len") + do_log(locals(), "subtract: sub_len = n + 1", sub_len="sub_len") VL = sub_len - do_log(locals(), sub_len=None) + do_log(locals(), "VL = sub_len", sub_len=None) for i in range(VL): # subfe not_product = ~product[i] % 2 ** self.word_size t += not_product + un[j + i] un[j + i] = t % 2 ** self.word_size t = int(t >= 2 ** self.word_size) - do_log(locals()) + do_log(locals(), "subtract: step") need_fixup = not t # Step D5: test remainder @@ -592,7 +606,7 @@ class DivModKnuthAlgorithmD: on_corner_case("add back") qhat -= 1 - do_log(locals()) + do_log(locals(), "add back: qhat -= 1") t = 0 for i in range(n): @@ -600,31 +614,33 @@ class DivModKnuthAlgorithmD: t += un[j + i] + vn[i] un[j + i] = t % 2 ** self.word_size t = int(t >= 2 ** self.word_size) - do_log(locals()) + do_log(locals(), "add back: step") un[j + n] += t - do_log(locals()) + do_log(locals(), "add back: un[j + n] += t") q[j] = qhat - do_log(locals(), index=None) + do_log(locals(), "q[j] = qhat", index=None) # Step D8: un-normalize # move s and n - do_log(locals(), s="s_for_unnorm", n="n_for_unnorm", + do_log(locals(), "un-normalize", s="s_for_unnorm", n="n_for_unnorm", vn=None, m=None, j=None) r = [0] * self.r_size # remainder - do_log(locals(), r=("r", self.r_size)) + do_log(locals(), "un-normalize: r = [0...]", r=("r", self.r_size)) # r = un >> s t = 0 - do_log(locals(), t="t_for_unnorm") + do_log(locals(), "un-normalize: t = 0", t="t_for_unnorm") for i in reversed(range(n)): # dsrd t <<= self.word_size t |= (un[i] << self.word_size) >> s r[i] = t >> self.word_size t %= 2 ** self.word_size - do_log(locals()) + do_log(locals(), "un-normalize: step") + + do_log(locals(), "finished un-normalize") return q, r