From: Luke Kenneth Casson Leighton <lkcl@lkcl.net>
Date: Wed, 6 Jul 2022 17:54:07 +0000 (+0100)
Subject: add first stub of svindex pseudocode
X-Git-Tag: sv_maxu_works-initial~278
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=c6fdfe18075f011288f35c18a7d267408838b08d;p=openpower-isa.git

add first stub of svindex pseudocode
https://bugs.libre-soc.org/show_bug.cgi?id=885
---

diff --git a/openpower/isa/simplev.mdwn b/openpower/isa/simplev.mdwn
index f407851e..eb791092 100644
--- a/openpower/isa/simplev.mdwn
+++ b/openpower/isa/simplev.mdwn
@@ -265,3 +265,38 @@ Special Registers Altered:
 
     None
 
+# svindex
+
+SVI-Form
+
+* svindex RS,rmm,SVd,ew,yz,mr,sk
+
+Pseudo-code:
+
+    # VL in Matrix Multiply is xd*yd*zd
+    n <- (0b00 || SVxd) * (0b00 || SVyd) * (0b00 || SVzd)
+    # set up template, then copy once location identified
+    shape = [0]*32
+    shape[30:31] <- 0b00                   # mode
+    if yz = 1 then shape[18:20] = 0b110      # indexed xd/yd
+    else           shape[18:20] = 0b111      # indexed yd/xd
+    shape[0:5] <- (0b0 || SVxd)   # xdim
+    shape[6:11] <- (0b0 || SVyd)   # ydim
+    shape[12:17] <- (0b0 || SVzd || 0b0)   # SVGPR
+    shape[28:29] <- ew                     # element-width override
+    if sk = 1 then shape[28:29] <- 0b01 # skip 1st dimension
+    else           shape[28:29] <- 0b00 # no skipping
+    # select the mode for updating SVSHAPEs
+    if mm = 0 then
+        # clear out all SVSHAPEs first
+        SVSHAPE0[0:31] <- [0] * 32
+        SVSHAPE1[0:31] <- [0] * 32
+        SVSHAPE2[0:31] <- [0] * 32
+        SVSHAPE3[0:31] <- [0] * 32
+        SVSTATE[42:46] <- rmm # rmm exactly REMAP.SVme
+        SVSTATE[62] <- 0      # persistence bit cleared
+
+Special Registers Altered:
+
+    None
+
diff --git a/src/openpower/decoder/isa/test_caller_svindex.py b/src/openpower/decoder/isa/test_caller_svindex.py
new file mode 100644
index 00000000..39ea23ed
--- /dev/null
+++ b/src/openpower/decoder/isa/test_caller_svindex.py
@@ -0,0 +1,88 @@
+"""SVP64 unit test for doing strange things to SVSTATE, manually.
+"""
+from nmigen import Module, Signal
+from nmigen.back.pysim import Simulator, Delay, Settle
+from nmutil.formaltest import FHDLTestCase
+import unittest
+from openpower.decoder.isa.caller import ISACaller
+from openpower.decoder.power_decoder import (create_pdecode)
+from openpower.decoder.power_decoder2 import (PowerDecode2)
+from openpower.simulator.program import Program
+from openpower.decoder.isa.caller import ISACaller, SVP64State, CRFields
+from openpower.decoder.selectable_int import SelectableInt
+from openpower.decoder.orderedset import OrderedSet
+from openpower.decoder.isa.all import ISA
+from openpower.decoder.isa.test_caller import Register, run_tst
+from openpower.sv.trans.svp64 import SVP64Asm
+from openpower.consts import SVP64CROffs
+from copy import deepcopy
+
+
+class SVSTATETestCase(FHDLTestCase):
+
+    def _check_regs(self, sim, expected):
+        print ("GPR")
+        sim.gpr.dump()
+        for i in range(32):
+            self.assertEqual(sim.gpr(i), SelectableInt(expected[i], 64))
+
+    def test_sv_index(self):
+        """sets VL=2 (via SVSTATE) with a manual srcstep/dststep,
+            then does a scalar-result add.  the result should be:
+
+                add 1, 6, 10
+
+            because whilst the Vector instruction was moved on by srcstep,
+            the Scalar one is NOT moved on.
+        """
+        isa = SVP64Asm(['svindex 1, 31, 5, 0, 0, 0, 0'
+                       ])
+        lst = list(isa)
+        print ("listing", lst)
+
+        # initial values in GPR regfile
+        initial_regs = [0] * 32
+        initial_regs[9] = 0x1234
+        initial_regs[10] = 0x1111
+        initial_regs[5] = 0x4321
+        initial_regs[6] = 0x2223
+
+        # SVSTATE vl=10
+        svstate = SVP64State()
+        svstate.vl = 10 # VL
+        svstate.maxvl = 10 # MAXVL
+        print ("SVSTATE", bin(svstate.asint()))
+
+        # copy before running
+        expected_regs = deepcopy(initial_regs)
+        #expected_regs[1] = 0x3334
+
+        with Program(lst, bigendian=False) as program:
+            sim = self.run_tst_program(program, initial_regs, svstate=svstate)
+            self._check_regs(sim, expected_regs)
+
+            print ("SVSTATE after", bin(sim.svstate.asint()))
+            print ("        vl", bin(sim.svstate.vl))
+            print ("        mvl", bin(sim.svstate.maxvl))
+            print ("    srcstep", bin(sim.svstate.srcstep))
+            print ("    dststep", bin(sim.svstate.dststep))
+            print ("      RMpst", bin(sim.svstate.RMpst))
+            print ("       SVme", bin(sim.svstate.SVme))
+            print ("        mo0", bin(sim.svstate.mo0))
+            print ("        mo1", bin(sim.svstate.mo1))
+            print ("        mi0", bin(sim.svstate.mi0))
+            print ("        mi1", bin(sim.svstate.mi1))
+            print ("        mi2", bin(sim.svstate.mi2))
+
+    def run_tst_program(self, prog, initial_regs=None,
+                              svstate=None):
+        if initial_regs is None:
+            initial_regs = [0] * 32
+        simulator = run_tst(prog, initial_regs, svstate=svstate)
+        simulator.gpr.dump()
+        return simulator
+
+
+if __name__ == "__main__":
+    unittest.main()
+