From: Luke Kenneth Casson Leighton <lkcl@lkcl.net>
Date: Tue, 28 Nov 2023 20:41:01 +0000 (+0000)
Subject: fix elwidth overrides when sw=8
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=43644212d858e0dd4ee8ee57b757617457ed695c;p=openpower-isa.git

fix elwidth overrides when sw=8
the way that XLEN works is it must be MAX(sw,dw) which is not what
was happening, it was fixed at sw (source width)
---

diff --git a/src/openpower/decoder/isa/caller.py b/src/openpower/decoder/isa/caller.py
index ae9ea147..8725f310 100644
--- a/src/openpower/decoder/isa/caller.py
+++ b/src/openpower/decoder/isa/caller.py
@@ -2160,7 +2160,7 @@ class ISACaller(ISACallerHelper, ISAFPHelpers, StepLoop):
             ew_src = 8 << (3-int(ew_src))  # convert to bitlength
             ew_dst = 8 << (3-int(ew_dst))  # convert to bitlength
             xlen = max(ew_src, ew_dst)
-            log("elwdith", ew_src, ew_dst)
+            log("elwidth", ew_src, ew_dst)
         log("XLEN:", self.is_svp64_mode, xlen)
 
         # look up instruction in ISA.instrs, prepare namespace
@@ -2256,7 +2256,7 @@ class ISACaller(ISACallerHelper, ISAFPHelpers, StepLoop):
             elif name in spr_byname:
                 inputs[name] = self.spr[name]
             else:
-                regval = (yield from self.get_input(name, ew_src))
+                regval = (yield from self.get_input(name, ew_src, xlen))
                 log("regval name", name, regval)
                 inputs[name] = regval
 
@@ -2557,7 +2557,7 @@ class ISACaller(ISACallerHelper, ISAFPHelpers, StepLoop):
             else:
                 self.namespace['D'] = imm
 
-    def get_input(self, name, ew_src):
+    def get_input(self, name, ew_src, xlen):
         # using PowerDecoder2, first, find the decoder index.
         # (mapping name RA RB RC RS to in1, in2, in3)
         regnum, is_vec = yield from get_idx_in(self.dec2, name, True)
@@ -2584,14 +2584,17 @@ class ISACaller(ISACallerHelper, ISAFPHelpers, StepLoop):
         if not self.is_svp64_mode or not self.pred_src_zero:
             log('reading reg %s %s' % (name, str(regnum)), is_vec)
             if name in fregs:
-                reg_val = SelectableInt(self.fpr(base, is_vec, offs, ew_src))
-                log("read reg %d/%d: 0x%x" % (base, offs, reg_val.value),
-                    kind=LogType.InstrInOuts)
+                fval = self.fpr(base, is_vec, offs, ew_src)
+                reg_val = SelectableInt(fval)
+                assert ew_src == XLEN, "TODO fix elwidth conversion"
                 self.trace("r:FPR:%d:%d:%d " % (base, offs, ew_src))
+                log("read fp reg %d/%d: 0x%x" % (base, offs, reg_val.value),
+                    kind=LogType.InstrInOuts)
             elif name is not None:
-                reg_val = SelectableInt(self.gpr(base, is_vec, offs, ew_src))
+                gval = self.gpr(base, is_vec, offs, ew_src)
+                reg_val = SelectableInt(gval.value, bits=xlen)
                 self.trace("r:GPR:%d:%d:%d " % (base, offs, ew_src))
-                log("read reg %d/%d: 0x%x" % (base, offs, reg_val.value),
+                log("read int reg %d/%d: 0x%x" % (base, offs, reg_val.value),
                     kind=LogType.InstrInOuts)
         else:
             log('zero input reg %s %s' % (name, str(regnum)), is_vec)
diff --git a/src/openpower/test/alu/svp64_cases.py b/src/openpower/test/alu/svp64_cases.py
index b86a1d12..638da111 100644
--- a/src/openpower/test/alu/svp64_cases.py
+++ b/src/openpower/test/alu/svp64_cases.py
@@ -34,6 +34,33 @@ class SVP64ALUElwidthTestCase(TestAccumulatorBase):
                       initial_svstate=svstate, expected=e)
 
 
+    def case_2_sv_add_sw8(self):
+        """>>> lst = ['sv.add/sw=8 *1, *5, *9']
+        """
+        isa = SVP64Asm(['sv.add/sw=8 *1, *5, *9'])
+        lst = list(isa)
+        print("listing", lst)
+
+        # initial values in GPR regfile
+        initial_regs = [0] * 32
+        initial_regs[9] = 0x1220
+        initial_regs[5] = 0x43ff
+        # SVSTATE (in this case, VL=2)
+        svstate = SVP64State()
+        svstate.vl = 2  # VL
+        svstate.maxvl = 2  # MAXVL
+        print("SVSTATE", bin(svstate.asint()))
+
+        # expected: each 8-bit add is completely independent
+        gprs = deepcopy(initial_regs)
+        gprs[1] = 0x11f # 0x20+0xff = 0x11f (64-bit)
+        gprs[2] = 0x55  # 0x12+0x43 = 0x55 (64-bit)
+        e = ExpectedState(pc=8, int_regs=gprs)
+
+        self.add_case(Program(lst, bigendian), initial_regs,
+                      initial_svstate=svstate, expected=e)
+
+
     def case_2_sv_add_ew32(self):
         """>>> lst = ['sv.add/w=32 *1, *5, *9']
         """