big convert g/s/r mid --> muxid

[ieee754fpu.git] / src / ieee754 / fpdiv / div0.py

diff --git a/src/ieee754/fpdiv/div0.py b/src/ieee754/fpdiv/div0.py
index 45a5f971fa8bf617dc47084770acc884d90ebcc4..2ad8bcdae5435c285834ac91a7e2690681c84b37 100644 (file)
--- a/src/ieee754/fpdiv/div0.py
+++ b/src/ieee754/fpdiv/div0.py
@@ -9,28 +9,30 @@ from nmigen.cli import main, verilog
 from ieee754.fpcommon.fpbase import (FPNumBaseRecord, Overflow)
 from ieee754.fpcommon.fpbase import FPState
 from ieee754.fpcommon.denorm import FPSCData
+from ieee754.fpcommon.getop import FPBaseData
 
 
 class FPDivStage0Data:
 
-    def __init__(self, width, id_wid):
+    def __init__(self, width, pspec):
         self.z = FPNumBaseRecord(width, False)
         self.out_do_z = Signal(reset_less=True)
         self.oz = Signal(width, reset_less=True)
         self.of = Overflow()
 
+        self.ctx = FPBaseData(width, pspec) # context: muxid, operator etc.
+        self.muxid = self.ctx.muxid             # annoying. complicated.
+
         # TODO: here is where Q and R would be put, and passed
         # down to Stage1 processing.
 
         mw = (self.z.m_width)*2 - 1 + 3 # sticky/round/guard bits + (2*mant) - 1
         self.product = Signal(mw, reset_less=True)
 
-        self.mid = Signal(id_wid, reset_less=True)
-
     def eq(self, i):
         return [self.z.eq(i.z), self.out_do_z.eq(i.out_do_z), self.oz.eq(i.oz),
                 self.of.eq(i.of),
-                self.product.eq(i.product), self.mid.eq(i.mid)]
+                self.product.eq(i.product), self.ctx.eq(i.ctx)]
 
 
 class FPDivStage0Mod(Elaboratable):
@@ -60,9 +62,13 @@ class FPDivStage0Mod(Elaboratable):
         m = Module()
 
         # XXX TODO, actual DIV code here.  this class would be
-        # "step one" which takes the pre-normalised data and
+        # "step one" which takes the pre-normalised data (see ispec) and
         # *begins* the processing phase (enters the massive DIV
-        # pipeline chain)
+        # pipeline chain) - see ospec.
+
+        # NOTE: this stage does *NOT* do *ACTUAL* DIV processing,
+        # it is PURELY the *ENTRY* point into the chain, performing
+        # "preparation" work
 
         # store intermediate tests (and zero-extended mantissas)
         am0 = Signal(len(self.i.a.m)+1, reset_less=True)
@@ -82,7 +88,7 @@ class FPDivStage0Mod(Elaboratable):
 
         m.d.comb += self.o.oz.eq(self.i.oz)
         m.d.comb += self.o.out_do_z.eq(self.i.out_do_z)
-        m.d.comb += self.o.mid.eq(self.i.mid)
+        m.d.comb += self.o.ctx.eq(self.i.ctx)
         return m