replace copy of FPState with import of FPState

[ieee754fpu.git] / src / add / fmul.py

diff --git a/src/add/fmul.py b/src/add/fmul.py
index 73da3e4c1f596367bb5717b11af3cb11622b466e..46ad8099874b28899484477e321a9b3171c56db1 100644 (file)
--- a/src/add/fmul.py
+++ b/src/add/fmul.py
@@ -1,8 +1,8 @@
-from nmigen import Module, Signal
+from nmigen import Module, Signal, Cat, Mux, Array, Const

 from nmigen.cli import main, verilog
 
 from fpbase import FPNum, FPOp, Overflow, FPBase
 from nmigen.cli import main, verilog
 
 from fpbase import FPNum, FPOp, Overflow, FPBase

-
+from nmigen_add_experiment import FPState

 
 class FPMUL(FPBase):
 
 
 class FPMUL(FPBase):
 


@@ -24,7 +24,7 @@ class FPMUL(FPBase):
         b = FPNum(self.width, False)
         z = FPNum(self.width, False)
 
         b = FPNum(self.width, False)
         z = FPNum(self.width, False)
 

-        mw = (self.m_width)*2 - 1 + 3 # sticky/round/guard bits + (2*mant) - 1
+        mw = (z.m_width)*2 - 1 + 3 # sticky/round/guard bits + (2*mant) - 1

         product = Signal(mw)
 
         of = Overflow()
         product = Signal(mw)
 
         of = Overflow()


@@ -47,37 +47,36 @@ class FPMUL(FPBase):
             # special cases
 
             with m.State("special_cases"):
             # special cases
 
             with m.State("special_cases"):

-                m.next = "normalise_a"

                 #if a or b is NaN return NaN
                 with m.If(a.is_nan() | b.is_nan()):
                 #if a or b is NaN return NaN
                 with m.If(a.is_nan() | b.is_nan()):

-                    m.next += "put_z"
+                    m.next = "put_z"

                     m.d.sync += z.nan(1)
                 #if a is inf return inf
                 with m.Elif(a.is_inf()):
                     m.d.sync += z.nan(1)
                 #if a is inf return inf
                 with m.Elif(a.is_inf()):

-                    m.next += "put_z"
-                    m.d.sync += z.inf(0)
-                #if b is zero return NaN
-                with m.If(b.is_zero()):
-                    m.d.sync += z.nan(1)
+                    m.next = "put_z"
+                    m.d.sync += z.inf(a.s ^ b.s)
+                    #if b is zero return NaN
+                    with m.If(b.is_zero()):
+                        m.d.sync += z.nan(1)

                 #if b is inf return inf
                 with m.Elif(b.is_inf()):
                 #if b is inf return inf
                 with m.Elif(b.is_inf()):

-                    m.next += "put_z"
-                    m.d.sync += z.inf(0)
-                #if a is zero return NaN
-                with m.If(a.is_zero()):
-                    m.next += "put_z"
-                    m.d.sync += z.nan(1)
+                    m.next = "put_z"
+                    m.d.sync += z.inf(a.s ^ b.s)
+                    #if a is zero return NaN
+                    with m.If(a.is_zero()):
+                        m.next = "put_z"
+                        m.d.sync += z.nan(1)

                 #if a is zero return zero
                 with m.Elif(a.is_zero()):
                 #if a is zero return zero
                 with m.Elif(a.is_zero()):

-                    m.next += "put_z"
-                    m.d.sync += z.zero(0)
+                    m.next = "put_z"
+                    m.d.sync += z.zero(a.s ^ b.s)

                 #if b is zero return zero
                 with m.Elif(b.is_zero()):
                 #if b is zero return zero
                 with m.Elif(b.is_zero()):

-                    m.next += "put_z"
-                    m.d.sync += z.zero(0)
+                    m.next = "put_z"
+                    m.d.sync += z.zero(a.s ^ b.s)

                 # Denormalised Number checks
                 with m.Else():
                 # Denormalised Number checks
                 with m.Else():

-                    m.next += "normalise_a"
+                    m.next = "normalise_a"

                     self.denormalise(m, a)
                     self.denormalise(m, b)
 
                     self.denormalise(m, a)
                     self.denormalise(m, b)
 


@@ -95,7 +94,7 @@ class FPMUL(FPBase):
 
             #multiply_0
             with m.State("multiply_0"):
 
             #multiply_0
             with m.State("multiply_0"):

-                m.next += "multiply_1"
+                m.next = "multiply_1"

                 m.d.sync += [
                    z.s.eq(a.s ^ b.s),
                    z.e.eq(a.e + b.e + 1),
                 m.d.sync += [
                    z.s.eq(a.s ^ b.s),
                    z.e.eq(a.e + b.e + 1),


@@ -104,12 +103,13 @@ class FPMUL(FPBase):
 
             #multiply_1
             with m.State("multiply_1"):
 
             #multiply_1
             with m.State("multiply_1"):

-                m.next += "normalise_1"
+                mw = z.m_width
+                m.next = "normalise_1"

                 m.d.sync += [
                 m.d.sync += [

-                z.m.eq(product[26:50]),
-                guard.eq(product[25]),
-                round_bit.eq(product[24]),
-                sticky.eq(product[0:23] != 0)
+                z.m.eq(product[mw+2:]),
+                of.guard.eq(product[mw+1]),
+                of.round_bit.eq(product[mw]),
+                of.sticky.eq(product[0:mw] != 0)

             ]
 
             # ******
             ]
 
             # ******


@@ -129,6 +129,12 @@ class FPMUL(FPBase):
             with m.State("round"):
                 self.roundz(m, z, of, "corrections")
 
             with m.State("round"):
                 self.roundz(m, z, of, "corrections")
 

+            # ******
+            # correction stage
+
+            with m.State("corrections"):
+                self.corrections(m, z, "pack")
+

             # ******
             # pack stage
             with m.State("pack"):
             # ******
             # pack stage
             with m.State("pack"):


@@ -142,175 +148,6 @@ class FPMUL(FPBase):
 
         return m
 
 
         return m
 

-"""
-special_cases:
-      begin
-        //if a is NaN or b is NaN return NaN
-        if ((a_e == 128 && a_m != 0) || (b_e == 128 && b_m != 0)) begin
-          z[31] <= 1;
-          z[30:23] <= 255;
-          z[22] <= 1;
-          z[21:0] <= 0;
-          state <= put_z;
-        //if a is inf return inf
-        end else if (a_e == 128) begin
-          z[31] <= a_s ^ b_s;
-          z[30:23] <= 255;
-          z[22:0] <= 0;
-          //if b is zero return NaN
-          if (($signed(b_e) == -127) && (b_m == 0)) begin
-            z[31] <= 1;
-            z[30:23] <= 255;
-            z[22] <= 1;
-            z[21:0] <= 0;
-          end
-          state <= put_z;
-        //if b is inf return inf
-        end else if (b_e == 128) begin
-          z[31] <= a_s ^ b_s;
-          z[30:23] <= 255;
-          z[22:0] <= 0;
-          //if a is zero return NaN
-          if (($signed(a_e) == -127) && (a_m == 0)) begin
-            z[31] <= 1;
-            z[30:23] <= 255;
-            z[22] <= 1;
-            z[21:0] <= 0;
-          end
-          state <= put_z;
-        //if a is zero return zero
-        end else if (($signed(a_e) == -127) && (a_m == 0)) begin
-          z[31] <= a_s ^ b_s;
-          z[30:23] <= 0;
-          z[22:0] <= 0;
-          state <= put_z;
-        //if b is zero return zero
-        end else if (($signed(b_e) == -127) && (b_m == 0)) begin
-          z[31] <= a_s ^ b_s;
-          z[30:23] <= 0;
-          z[22:0] <= 0;
-          state <= put_z;
-          //^ done up to here
-        end else begin
-          //Denormalised Number
-          if ($signed(a_e) == -127) begin
-            a_e <= -126;
-          end else begin
-            a_m[23] <= 1;
-          end
-          //Denormalised Number
-          if ($signed(b_e) == -127) begin
-            b_e <= -126;
-          end else begin
-            b_m[23] <= 1;
-          end
-          state <= normalise_a;
-        end
-      end
-
-      normalise_a:
-      begin
-        if (a_m[23]) begin
-          state <= normalise_b;
-        end else begin
-          a_m <= a_m << 1;
-          a_e <= a_e - 1;
-        end
-      end
-
-      normalise_b:
-      begin
-        if (b_m[23]) begin
-          state <= multiply_0;
-        end else begin
-          b_m <= b_m << 1;
-          b_e <= b_e - 1;
-        end
-      end
-
-      multiply_0:
-      begin
-        z_s <= a_s ^ b_s;
-        z_e <= a_e + b_e + 1;
-        product <= a_m * b_m * 4;
-        state <= multiply_1;
-      end
-
-      multiply_1:
-      begin
-        z_m <= product[49:26];
-        guard <= product[25];
-        round_bit <= product[24];
-        sticky <= (product[23:0] != 0);
-        state <= normalise_1;
-      end
-
-      normalise_1:
-      begin
-        if (z_m[23] == 0) begin
-          z_e <= z_e - 1;
-          z_m <= z_m << 1;
-          z_m[0] <= guard;
-          guard <= round_bit;
-          round_bit <= 0;
-        end else begin
-          state <= normalise_2;
-        end
-      end
-
-      normalise_2:
-      begin
-        if ($signed(z_e) < -126) begin
-          z_e <= z_e + 1;
-          z_m <= z_m >> 1;
-          guard <= z_m[0];
-          round_bit <= guard;
-          sticky <= sticky | round_bit;
-        end else begin
-          state <= round;
-        end
-      end
-
-      round:
-      begin
-        if (guard && (round_bit | sticky | z_m[0])) begin
-          z_m <= z_m + 1;
-          if (z_m == 24'hffffff) begin
-            z_e <=z_e + 1;
-          end
-        end
-        state <= pack;
-      end
-
-      pack:
-      begin
-        z[22 : 0] <= z_m[22:0];
-        z[30 : 23] <= z_e[7:0] + 127;
-        z[31] <= z_s;
-        if ($signed(z_e) == -126 && z_m[23] == 0) begin
-          z[30 : 23] <= 0;
-        end
-        //if overflow occur
-        s, return inf
-        if ($signed(z_e) > 127) begin
-          z[22 : 0] <= 0;
-          z[30 : 23] <= 255;
-          z[31] <= z_s;
-        end
-        state <= put_z;
-      end
-
-      put_z:
-      begin
-        s_output_z_stb <= 1;
-        s_output_z <= z;
-        if (s_output_z_stb && output_z_ack) begin
-          s_output_z_stb <= 0;
-          state <= get_a;
-        end
-end
-
-"""

 
 if __name__ == "__main__":
     alu = FPMUL(width=32)
 
 if __name__ == "__main__":
     alu = FPMUL(width=32)