Another round of minor updates to gf arithmetic bloqs (#1727)

- Make `GF2Addition` self inverse
- Fix a bug in symbolic resource estimation of `SynthesizeLRCircuit`.

Author: tanujkhattar

qualtran/bloqs/gf_arithmetic/gf2_addition.py

@@ -78,6 +78,9 @@ def on_classical_vals(self, *, x, y) -> Dict[str, 'ClassicalValT']:
         assert isinstance(x, self.qgf.gf_type) and isinstance(y, self.qgf.gf_type)
         return {'x': x, 'y': x + y}
 
+    def adjoint(self) -> 'Bloq':
+        return self
+
 
 @bloq_example
 def _gf16_addition() -> GF2Addition:

qualtran/bloqs/gf_arithmetic/gf2_multiplication.py

@@ -34,7 +34,7 @@
     Signature,
 )
 from qualtran.bloqs.basic_gates import CNOT, CZ, Discard, MeasureX, Toffoli
-from qualtran.symbolics import ceil, is_symbolic, log2, Shaped, SymbolicInt
+from qualtran.symbolics import is_symbolic, log2, Shaped, SymbolicInt
 
 if TYPE_CHECKING:
     from qualtran import BloqBuilder, Soquet, SoquetT
@@ -130,8 +130,8 @@ def build_call_graph(
         self, ssa: 'SympySymbolAllocator'
     ) -> Union['BloqCountDictT', Set['BloqCountT']]:
         n = self.matrix.shape[0]
-        if is_symbolic(n):
-            return {CNOT(): ceil(n**2)}
+        if isinstance(self.matrix, Shaped):
+            return {CNOT(): n**2 - n}
         L, U, _ = self.lup
         # The number of cnots is the number of non zero off-diagnoal entries in L and U.
         cnots = np.sum(L) + np.sum(U) - 2 * self.n

qualtran/bloqs/gf_arithmetic/gf2_multiplication_test.py

@@ -16,6 +16,7 @@
 
 import numpy as np
 import pytest
+import sympy
 from galois import GF, Poly
 
 import qualtran.testing as qlt_testing
@@ -37,6 +38,7 @@
 from qualtran.resource_counting import get_cost_value, QECGatesCost
 from qualtran.resource_counting.generalizers import ignore_alloc_free, ignore_split_join
 from qualtran.simulation.classical_sim import do_phased_classical_simulation
+from qualtran.symbolics import Shaped
 from qualtran.testing import assert_consistent_classical_action
 
 
@@ -79,6 +81,17 @@ def test_synthesize_lr_circuit_slow(m):
         assert i == QGFM.from_bits([*bloq_adj_out])
 
 
+def test_synthesize_lr_circuit_symbolic_resource():
+    bloq = SynthesizeLRCircuit(Shaped((4, 4)))
+    assert get_cost_value(bloq, QECGatesCost()).clifford == 12
+    assert get_cost_value(bloq.adjoint(), QECGatesCost()).clifford == 12
+
+    n = sympy.Symbol("n")
+    bloq = SynthesizeLRCircuit(Shaped((n, n)))
+    assert get_cost_value(bloq, QECGatesCost()).clifford == n**2 - n
+    assert get_cost_value(bloq.adjoint(), QECGatesCost()).clifford == n**2 - n
+
+
 def test_gf2_plus_equal_prod_classical_sim_quick():
     m = 2
     bloq = GF2Multiplication(QGF(2, m), plus_equal_prod=True)

qualtran/bloqs/gf_arithmetic/gf2_square_test.py

@@ -18,7 +18,6 @@
 
 from qualtran.bloqs.gf_arithmetic.gf2_square import _gf2_square_symbolic, _gf16_square, GF2Square
 from qualtran.resource_counting import get_cost_value, QECGatesCost
-from qualtran.symbolics import ceil
 from qualtran.testing import assert_consistent_classical_action
 
 
@@ -41,7 +40,7 @@ def test_gf2_square_resource():
     bloq = _gf2_square_symbolic.make()
     m = bloq.bitsize
     assert get_cost_value(bloq, QECGatesCost()).total_t_count() == 0
-    expected_expr = ceil(m**2)
+    expected_expr = m**2 - m
     assert isinstance(expected_expr, sympy.Expr)
     assert sympy.simplify(get_cost_value(bloq, QECGatesCost()).clifford - expected_expr) == 0