Escape backslashes in Python comments.

The latest version of flake8 diagnoses these as invalid escape
sequences, so properly escape them.

lib/codegen/meta-python/base/instructions.py

@@ -1134,7 +1134,7 @@ srem_imm = Instruction(
 
 irsub_imm = Instruction(
         'irsub_imm', """
-        Immediate reverse wrapping subtraction: :math:`a := Y - x \pmod{2^B}`.
+        Immediate reverse wrapping subtraction: :math:`a := Y - x \\pmod{2^B}`.
 
         Also works as integer negation when :math:`Y = 0`. Use :inst:`iadd_imm`
         with a negative immediate operand for the reverse immediate

lib/codegen/meta-python/cdsl/instructions.py

@@ -345,7 +345,7 @@ class Instruction(object):
         `(inst, typevars)` pair.
 
         This version in `Instruction` itself allows non-polymorphic
-        instructions to duck-type as `BoundInstruction`\s.
+        instructions to duck-type as `BoundInstruction`\\s.
         """
         assert not self.is_polymorphic, self
         return (self, ())

lib/codegen/meta-python/cdsl/test_ti.py

@@ -98,7 +98,7 @@ def check_concrete_typing_rtl(var_types, rtl):
     Check that a concrete type assignment var_types (Dict[Var, TypeVar]) is
     valid for an Rtl rtl. Specifically check that:
 
-    1) For each Var v \in rtl, v is defined in var_types
+    1) For each Var v \\in rtl, v is defined in var_types
 
     2) For all v, var_types[v] is a singleton type
 

lib/codegen/meta-python/cdsl/ti.py

@@ -419,7 +419,7 @@ class TypeEnv(object):
         E.g. if we have a root of the tree that looks like:
 
           typeof_a   typeof_b
-                 \  /
+                 \\  /
               typeof_x
                   |
                 half_width(1)
@@ -430,7 +430,7 @@ class TypeEnv(object):
         resulting graph is:
 
           typeof_a   typeof_b
-                 \  /
+                 \\  /
               typeof_x
         """
         source_tvs = set([v.get_typevar() for v in self.vars])

lib/codegen/meta-python/cdsl/typevar.py

@@ -120,7 +120,7 @@ def legal_bool(bits):
     # type: (int) -> bool
     """
     True iff bits is a legal bit width for a bool type.
-    bits == 1 || bits \in { 8, 16, .. MAX_BITS }
+    bits == 1 || bits \\in { 8, 16, .. MAX_BITS }
     """
     return bits == 1 or \
         (bits >= 8 and bits <= MAX_BITS and is_power_of_two(bits))

lib/codegen/meta-python/cdsl/xform.py

@@ -113,7 +113,7 @@ class Rtl(object):
         # type: (Rtl) -> None
         """
         Given that there is only 1 possible concrete typing T for self, assign
-        a singleton TV with type t=T[v] for each Var v \in self. Its an error
+        a singleton TV with type t=T[v] for each Var v \\in self. Its an error
         to call this on an Rtl with more than 1 possible typing. This modifies
         the Rtl in-place.
         """

lib/codegen/meta-python/semantics/__init__.py

@@ -19,11 +19,11 @@ def verify_semantics(inst, src, xforms):
     Verify that the semantics transforms in xforms correctly describe the
     instruction described by the src Rtl. This involves checking that:
         0) src is a single instance of inst
-        1) For all x\in xforms x.src is a single instance of inst
+        1) For all x \\in xforms x.src is a single instance of inst
         2) For any concrete values V of Literals in inst:
             For all concrete typing T of inst:
-                Exists single x \in xforms that applies to src conretazied to V
-                and T
+                Exists single x \\in xforms that applies to src conretazied to
+                V and T
     """
     # 0) The source rtl is always a single instance of inst
     assert len(src.rtl) == 1 and src.rtl[0].expr.inst == inst