nir/algebraic: Don't put quotes around floating point literals

The quotation marks around 1.0 cause it to be treated as a string
instead of a floating point value.  The generator then treats it as an
arbitrary variable replacement, so any iand involving a ('ineg', ('b2i',
a)) matches.

v2: Remove misleading comment about sized literals (suggested by
Timothy).  Add assertion that the name of a varible is entierly
alphabetic (suggested by Jason).

Signed-off-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Tested-by: Timothy Arceri <tarceri@itsqueeze.com> [v1]
Reviewed-by: Timothy Arceri <tarceri@itsqueeze.com> [v1]
Fixes: 6bcd2af086 ("nir/algebraic: Add some optimizations for D3D-style Booleans")
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=109075

src/compiler/nir/nir_algebraic.py

@@ -252,6 +252,14 @@ class Variable(Value):
       assert m and m.group('name') is not None
 
       self.var_name = m.group('name')
+
+      # Prevent common cases where someone puts quotes around a literal
+      # constant.  If we want to support names that have numeric or
+      # punctuation characters, we can me the first assertion more flexible.
+      assert self.var_name.isalpha()
+      assert self.var_name is not 'True'
+      assert self.var_name is not 'False'
+
       self.is_constant = m.group('const') is not None
       self.cond = m.group('cond')
       self.required_type = m.group('type')

src/compiler/nir/nir_opt_algebraic.py

@@ -61,10 +61,10 @@ d = 'd'
 #
 # All expression types can have a bit-size specified.  For opcodes, this
 # looks like "op@32", for variables it is "a@32" or "a@uint32" to specify a
-# type and size, and for literals, you can write "2.0@32".  In the search half
-# of the expression this indicates that it should only match that particular
-# bit-size.  In the replace half of the expression this indicates that the
-# constructed value should have that bit-size.
+# type and size.  In the search half of the expression this indicates that it
+# should only match that particular bit-size.  In the replace half of the
+# expression this indicates that the constructed value should have that
+# bit-size.
 
 optimizations = [
 
@@ -545,7 +545,7 @@ optimizations = [
    (('ieq', ('ineg', ('b2i', 'a@1')), -1), a),
    (('ine', ('ineg', ('b2i', 'a@1')), 0), a),
    (('ine', ('ineg', ('b2i', 'a@1')), -1), ('inot', a)),
-   (('iand', ('ineg', ('b2i', a)), '1.0@32'), ('b2f', a)),
+   (('iand', ('ineg', ('b2i', a)), 1.0), ('b2f', a)),
 
    # Conversions
    (('i2b32', ('b2i', 'a@32')), a),