[meta-python] Fix typos;

cranelift/codegen/meta-python/base/entities.py

@@ -19,7 +19,7 @@ stack_slot = EntityRefKind('stack_slot', 'A stack slot.')
 #: A reference to a global value.
 global_value = EntityRefKind('global_value', 'A global value.')
 
-#: A reference to a function sugnature declared in the function preamble.
+#: A reference to a function signature declared in the function preamble.
 #: This is used to provide the call signature in a call_indirect instruction.
 sig_ref = EntityRefKind('sig_ref', 'A function signature.')
 

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

@@ -252,7 +252,7 @@ class Instruction(object):
         for opnum in self.value_opnums:
             typ = self.ins[opnum].typevar
             tv = typ.free_typevar()
-            # Non-polymorphic or derived form ctrl_typevar is OK.
+            # Non-polymorphic or derived from ctrl_typevar is OK.
             if tv is None or tv is ctrl_typevar:
                 continue
             # No other derived typevars allowed.

cranelift/codegen/meta-python/gen_instr.py

@@ -364,7 +364,7 @@ def gen_opcodes(groups, fmt):
     # We explicitly set the discriminant of the first variant to 1, which
     # allows us to take advantage of the NonZero optimization, meaning that
     # wrapping enums can use the 0 discriminant instead of increasing the size
-    # if the whole type, and so SIZEOF(Option<Opcode>>) == SIZEOF(Opcode)
+    # of the whole type, and so SIZEOF(Option<Opcode>>) == SIZEOF(Opcode)
     is_first_opcode = True
     with fmt.indented('pub enum Opcode {', '}'):
         for g in groups: