From cc676ac3e82b70102a46eec7f3c99269e55f143b Mon Sep 17 00:00:00 2001 From: Luke Kenneth Casson Leighton Date: Mon, 18 Dec 2023 10:59:49 +0000 Subject: [PATCH] bug 676: add start of svp64 maxloc, based on pospopcount --- .../decoder/isa/test_caller_svp64_maxloc.py | 51 ++++++++++++++++--- 1 file changed, 43 insertions(+), 8 deletions(-) diff --git a/src/openpower/decoder/isa/test_caller_svp64_maxloc.py b/src/openpower/decoder/isa/test_caller_svp64_maxloc.py index 789ac9cd..eba6370c 100644 --- a/src/openpower/decoder/isa/test_caller_svp64_maxloc.py +++ b/src/openpower/decoder/isa/test_caller_svp64_maxloc.py @@ -20,18 +20,31 @@ from openpower.util import log -# example sv.cmpi/ff=lt 0, 1, *10, 5 +def cmpd(x, y): + class CRfield: + def __repr__(self): + return "" % (self.lt, self.gt, self.eq) + def __int__(self): + return (CRf.lt<<3) | (CRf.gt<<2) | (CRf.eq<<1) + CRf = CRfield() + CRf.lt = x < y + CRf.gt = x > y + CRf.eq = x == y + return CRf + + +# example sv.minmax/ff=lt 0, 1, *10, 5 # see https://bugs.libre-soc.org/show_bug.cgi?id=1183#c3 -def sv_maxu(gpr, CR, vl, ra, rb, rt): - i = 0 +def sv_maxu(gpr, vl, ra, rb, rt): + CR0, i = None, 0 while i < vl: - CR[0] = cmpd(gpr[ra+i], gpr[rb]) - log("sv_maxss test", i, gpr[ra + i], gpr[rb], CR[0], int(CR[0])) - gpr[rt] = gpr[ra+i] if CR[0].lt else gpr[rb] - if not CR[0].gt: + CR0 = cmpd(gpr[ra+i], gpr[rb]) + log("sv_maxss test", i, gpr[ra + i], gpr[rb], CR0, int(CR0)) + gpr[rt] = gpr[ra+i] if CR0.lt else gpr[rb] + if not CR0.gt: break i += 1 - return i # new VL + return i, CR0 # new VL class DDFFirstTestCase(FHDLTestCase): @@ -53,7 +66,29 @@ class DDFFirstTestCase(FHDLTestCase): self.sv_maxloc([2,1,3,0]) def sv_maxloc(self, ra): + """ + m, nm, i, n = 0, 0, 0, len(a) + while (i m): m, nm, i = a[i], i, i+1 + return nm + """ + lst = SVP64Asm(["sv.minmax./ff=le 4, *10, 4, 1" # scalar RB=RT + "mtspr 9, 3", # move r3 to CTR + # VL = MIN(CTR,MAXVL=8) + "setvl 3,0,8,0,1,1", # set MVL=8, VL=MIN(MVL,CTR) + # load VL bytes (update r4 addr) but compressed (dw=8) + "addi 6, 0, 0", # initialise r6 to zero + "sv.lbzu/pi/dw=8 *6, 1(4)", # should be /lf here as well + # gather performs the transpose (which gets us to positional..) + "gbbd 8,6", + # now those bits have been turned around, popcount and sum them + "setvl 0,0,8,0,1,1", # set MVL=VL=8 + "sv.popcntd/sw=8 *24,*8", # do the (now transposed) popcount + "sv.add *16,*16,*24", # and accumulate in results + # branch back if CTR still non-zero. works even though VL=8 + "sv.bc/all 16, *0, -0x28", # reduce CTR by VL and stop if -ve ]) lst = list(lst) -- 2.30.2