[Mesa-dev] [PATCH 38/41] glapi: glX_proto_size.py: Remove dead code.

[Ian Romanick]

Did you try commenting the 'return 0' to see how that affected the
binary size?  My old experiment was stupid... I just looked at 'ls -l'
on the .o file.  A better experiment is to look at the output of 'size
libglapi.so.0.0.0'.

On 03/31/2016 05:04 PM, Dylan Baker wrote:
> This code has for a long time returned 0 on entry. This makes the code
> dead, and the one place it is invoked a no-op if statement (it will
> always go down the if path).
> 
> Thanks to version control it's rather simple to restore it if someday
> someone decides that they want it.
> 
> Signed-off-by: Dylan Baker <dylanx.c.baker at intel.com>
> ---
>  src/mapi/glapi/gen/glX_proto_size.py | 77 +-----------------------------------
>  1 file changed, 1 insertion(+), 76 deletions(-)
> 
> diff --git a/src/mapi/glapi/gen/glX_proto_size.py b/src/mapi/glapi/gen/glX_proto_size.py
> index b8625a6..e4d685b 100644
> --- a/src/mapi/glapi/gen/glX_proto_size.py
> +++ b/src/mapi/glapi/gen/glX_proto_size.py
> @@ -104,80 +104,6 @@ class glx_enum_function(object):
>      def is_set(self):
>          return self.mode
>  
> -    def PrintUsingTable(self):
> -        """Emit the body of the __gl*_size function using a pair
> -        of look-up tables and a mask.  The mask is calculated such
> -        that (e & mask) is unique for all the valid values of e for
> -        this function.  The result of (e & mask) is used as an index
> -        into the first look-up table.  If it matches e, then the
> -        same entry of the second table is returned.  Otherwise zero
> -        is returned.
> -
> -        It seems like this should cause better code to be generated.
> -        However, on x86 at least, the resulting .o file is about 20%
> -        larger then the switch-statment version.  I am leaving this
> -        code in because the results may be different on other
> -        platforms (e.g., PowerPC or x86-64)."""
> -
> -        return 0
> -        count = 0
> -        for a in self.enums:
> -            count += 1
> -
> -        if -1 in self.count:
> -            return 0
> -
> -        # Determine if there is some mask M, such that M = (2^N) - 1,
> -        # that will generate unique values for all of the enums.
> -
> -        mask = 0
> -        for i in [1, 2, 3, 4, 5, 6, 7, 8]:
> -            mask = (1 << i) - 1
> -
> -            fail = 0
> -            for a in self.enums:
> -                for b in self.enums:
> -                    if a != b:
> -                        if (a & mask) == (b & mask):
> -                            fail = 1
> -
> -            if not fail:
> -                break
> -            else:
> -                mask = 0
> -
> -        if (mask != 0) and (mask < (2 * count)):
> -            masked_enums = {}
> -            masked_count = {}
> -
> -            for i in xrange(mask + 1):
> -                masked_enums[i] = "0"
> -                masked_count[i] = 0
> -
> -            for c in self.count:
> -                for e in self.count[c]:
> -                    i = e & mask
> -                    enum_obj = self.enums[e][0]
> -                    masked_enums[i] = '0x%04x /* %s */' % (e, enum_obj.name)
> -                    masked_count[i] = c
> -
> -            print '    static const GLushort a[%u] = {' % (mask + 1)
> -            for e in masked_enums:
> -                print '        %s, ' % (masked_enums[e])
> -            print '    };'
> -
> -            print '    static const GLubyte b[%u] = {' % (mask + 1)
> -            for c in masked_count:
> -                print '        %u, ' % (masked_count[c])
> -            print '    };'
> -
> -            print '    const unsigned idx = (e & 0x%02xU);' % (mask)
> -            print ''
> -            print '    return (e == a[idx]) ? (GLint) b[idx] : 0;'
> -            return True
> -        else:
> -            return False
> -
>      def PrintUsingSwitch(self, name):
>          """Emit the body of the __gl*_size function using a switch-statement."""
>  
> @@ -221,8 +147,7 @@ class glx_enum_function(object):
>          print '__gl%s_size( GLenum e )' % (name)
>          print '{'
>  
> -        if not self.PrintUsingTable():
> -            self.PrintUsingSwitch(name)
> +        self.PrintUsingSwitch(name)
>  
>          print '}'
>          print ''
>