From 7ee4eb5c8bbfd6ed7c8fd4e7d4b9580c882c7929 Mon Sep 17 00:00:00 2001
From: Luke Kenneth Casson Leighton <lkcl@lkcl.net>
Date: Thu, 1 Jul 2021 18:59:13 +0100
Subject: [PATCH] add matrix remap example

---
 openpower/sv/remap.mdwn     |  6 ++--
 openpower/sv/remapmatrix.py | 38 +++++++++++++++++++++
 openpower/sv/remapyield.py  | 67 +++++++++++++++++++++----------------
 3 files changed, 80 insertions(+), 31 deletions(-)
 create mode 100644 openpower/sv/remapmatrix.py

diff --git a/openpower/sv/remap.mdwn b/openpower/sv/remap.mdwn
index 4c625febc..966a98138 100644
--- a/openpower/sv/remap.mdwn
+++ b/openpower/sv/remap.mdwn
@@ -125,9 +125,9 @@ assuming that instruction is of the form FRT,FRA,FRC,FRB.
 
 Form: SVM-Form SV "Matrix" Form (see [[isatables/fields.text]])
 
-| 0.5|6.10  |11.15  |16..20  | 21..30 |31|  name    |
-| -- | --   | ---   | ------ | ------ |--| -------- |
-|OPCD| SVxd | SVyd  | SVRM   | XO     |/ | svremap  |
+| 0.5|6.10  |11.15  |16..20 | 21..25 | 26..30 |31|  name    |
+| -- | --   | ---   | ----- | ------ | ------ |--| -------- |
+|OPCD| SVxd | SVyd  | SVzd  | SVRM   | XO     |/ | svremap  |
 
 Fields:
 
diff --git a/openpower/sv/remapmatrix.py b/openpower/sv/remapmatrix.py
new file mode 100644
index 000000000..7c94b8947
--- /dev/null
+++ b/openpower/sv/remapmatrix.py
@@ -0,0 +1,38 @@
+from remapyield import iterate_indices
+
+def matrix_demo():
+    X = [[1, 2, 3],
+          [3, 4, 5],
+         ]
+    Y = [[6, 7],
+          [8, 9],
+          [10, 11],
+         ]
+    # 3x3 matrix
+    X = [[12,7,3],
+        [4 ,5,6],
+        [7 ,8,9]]
+    # 3x4 matrix
+    Y = [[5,8,1,2],
+        [6,7,3,0],
+        [4,5,9,1]]
+    xdim1 = len(X[0])
+    ydim1 = len(X)
+    xdim2 = len(Y[0])
+    ydim2 = len(Y)
+    # set up result matrix of correct size
+    result = []
+    for _ in range(ydim1):
+        result.append([0]*xdim2)
+    # iterate through rows of X
+    for i in range(len(X)):
+       # iterate through columns of Y
+       for j in range(len(Y[0])):
+           # iterate through rows of Y
+           for k in range(len(Y)):
+               result[i][j] += X[i][k] * Y[k][j]
+    for r in result:
+        print (r)
+
+if __name__ == '__main__':
+    matrix_demo()
diff --git a/openpower/sv/remapyield.py b/openpower/sv/remapyield.py
index c3a5f5301..4cca1f39a 100644
--- a/openpower/sv/remapyield.py
+++ b/openpower/sv/remapyield.py
@@ -1,48 +1,59 @@
 # a "yield" version of the REMAP algorithm. a little easier to read
 # than the Finite State Machine version
 
-# set the dimension sizes here
-xdim = 3
-ydim = 2
-zdim = 1
-
-# set total (can repeat, e.g. VL=x*y*z*4)
-VL = xdim * ydim * zdim
-
-lims = [xdim, ydim, zdim]
-idxs = [0,0,0]   # starting indices
-order = [1,0,2]  # experiment with different permutations, here
-offset = 0       # experiment with different offset, here
-invxyz = [0,1,0] # inversion if desired
-
 # python "yield" can be iterated. use this to make it clear how
 # the indices are generated by using natural-looking nested loops
-def iterate_indices():
+def iterate_indices(SVSHAPE):
     # get indices to iterate over, in the required order
-    xd = lims[order[2]]
-    yd = lims[order[1]]
-    zd = lims[order[0]]
+    xd = SVSHAPE.lims[SVSHAPE.order[2]]
+    yd = SVSHAPE.lims[SVSHAPE.order[1]]
+    zd = SVSHAPE.lims[SVSHAPE.order[0]]
     # create lists of indices to iterate over in each dimension
     x_r = list(range(xd))
     y_r = list(range(yd))
     z_r = list(range(zd))
     # invert the indices if needed
-    if invxyz[order[2]]: x_r.reverse()
-    if invxyz[order[1]]: y_r.reverse()
-    if invxyz[order[0]]: z_r.reverse()
+    if SVSHAPE.invxyz[SVSHAPE.order[2]]: x_r.reverse()
+    if SVSHAPE.invxyz[SVSHAPE.order[1]]: y_r.reverse()
+    if SVSHAPE.invxyz[SVSHAPE.order[0]]: z_r.reverse()
     # start an infinite (wrapping) loop
+    skip = 0
     while True:
         for x in x_r:           # loop over 3rd order dimension
             for y in y_r:       # loop over 2nd order dimension
                 for z in z_r:   # loop over 1st order dimension
+                    # skip the first entries up to offset
+                    if skip < SVSHAPE.offset:
+                        skip += 1
+                        continue
                     # construct the (up to) 3D remap schedule
                     yield (x + y * xd + z * xd * yd)
 
-# enumerate over the iterator function, getting new indices
-for idx, new_idx in enumerate(iterate_indices()):
-    if idx < offset:
-        continue
-    if idx >= offset + VL:
-        break
-    print ("%d->%d" % (idx, new_idx))
+def demo():
+    # set the dimension sizes here
+    xdim = 3
+    ydim = 2
+    zdim = 1
+
+    # set total (can repeat, e.g. VL=x*y*z*4)
+    VL = xdim * ydim * zdim
+
+    # set up an SVSHAPE
+    class SVSHAPE:
+        pass
+    SVSHAPE0 = SVSHAPE()
+    SVSHAPE0.lims = [xdim, ydim, zdim]
+    SVSHAPE0.idxs = [0,0,0]   # starting indices
+    SVSHAPE0.order = [1,0,2]  # experiment with different permutations, here
+    SVSHAPE0.offset = 0       # experiment with different offset, here
+    SVSHAPE0.invxyz = [0,1,0] # inversion if desired
+
+    # enumerate over the iterator function, getting new indices
+    for idx, new_idx in enumerate(iterate_indices(SVSHAPE0)):
+        if idx >= VL:
+            break
+        print ("%d->%d" % (idx, new_idx))
 
+# run the demo
+if __name__ == '__main__':
+    demo()
-- 
2.30.2