python: Use explicit integer divisions

In Python 2, divisions of integers return an integer:

    >>> 32 / 4
    8

In Python 3 though, they return floats:

    >>> 32 / 4
    8.0

However, Python 3 has an explicit integer division operator:

    >>> 32 // 4
    8

That operator exists on Python >= 2.2, so let's use it everywhere to
make the scripts compatible with both Python 2 and 3.

In addition, using __future__.division tells Python 2 to behave the same
way as Python 3, which helps ensure the scripts produce the same output
in both versions of Python.

Signed-off-by: Mathieu Bridon <[email protected]>
Reviewed-by: Eric Engestrom <[email protected]> (v2)
Reviewed-by: Dylan Baker <[email protected]>

2 files changed, 7 insertions, 4 deletions

diff --git a/src/gallium/auxiliary/util/u_format_pack.py b/src/gallium/auxiliary/util/u_format_pack.py
index 7a952a48b30..ad2e49281fb 100644
--- a/src/gallium/auxiliary/util/u_format_pack.py
+++ b/src/gallium/auxiliary/util/u_format_pack.py
@@ -36,7 +36,7 @@
 '''
 
 
-from __future__ import print_function
+from __future__ import division, print_function
 
 from u_format_parse import *
 
@@ -240,7 +240,7 @@ def value_to_native(type, value):
             return truncate_mantissa(value, 23)
         return value
     if type.type == FIXED:
-        return int(value * (1 << (type.size/2)))
+        return int(value * (1 << (type.size // 2)))
     if not type.norm:
         return int(value)
     if type.type == UNSIGNED:
diff --git a/src/gallium/auxiliary/util/u_format_parse.py b/src/gallium/auxiliary/util/u_format_parse.py
index c0456f6d159..d3874cd895b 100644
--- a/src/gallium/auxiliary/util/u_format_parse.py
+++ b/src/gallium/auxiliary/util/u_format_parse.py
@@ -29,6 +29,9 @@
 '''
 
 
+from __future__ import division
+
+
 VOID, UNSIGNED, SIGNED, FIXED, FLOAT = range(5)
 
 SWIZZLE_X, SWIZZLE_Y, SWIZZLE_Z, SWIZZLE_W, SWIZZLE_0, SWIZZLE_1, SWIZZLE_NONE, = range(7)
@@ -76,7 +79,7 @@ class Channel:
         if self.type == FLOAT:
             return VERY_LARGE
         if self.type == FIXED:
-            return (1 << (self.size/2)) - 1
+            return (1 << (self.size // 2)) - 1
         if self.norm:
             return 1
         if self.type == UNSIGNED:
@@ -90,7 +93,7 @@ class Channel:
         if self.type == FLOAT:
             return -VERY_LARGE
         if self.type == FIXED:
-            return -(1 << (self.size/2))
+            return -(1 << (self.size // 2))
         if self.type == UNSIGNED:
             return 0
         if self.norm: