freetype2/include
David Turner a5f33eeb8a Speed up ARMv7 support.
When building for ARMv7 with thumb2 instructions, the optimized
`FT_MulFix_arm' assembly routine was not being used.

The reason for this is in the `ftconfig.h' header, namely:

- The assembly routine uses the `smull' instruction which is not
  available when generating Thumb-1 machine code.  It is available
  in Thumb-2 mode, though.

- The header was written a long time ago before Thumb-2 became
  widely popular (e.g. with Android).  So it simply doesn't use the
  assembly routine if the `__thumb__' built-in macro is defined.

- When compiling in Thumb-2 mode, the compiler will define both
  `__thumb__' and `__thumb2__'.

By checking for `(__thumb2__ || !__thumb__)', we ensure that the
assembly routine is only avoided when generating Thumb-1 code.

Given that this is performance-sensitive function, this improves
`ftbench' as follows on a Galaxy Nexus:

                           Before (us/op)   After (us/op)

  - loading Arial.ttf glyphs at 14 ppem [1]

      Load                   34.285          33.098

  - same operation with the light auto-hinter [2]

      Load                   31.317          29.590

  - same operation without hinting [3]

      Load                    6.143           5.376

  - loading Arial.ttf advances at 14 ppem [4]

      Load_Advances (normal) 34.216          33.016
      Load_Advances (fast)    0.176           0.176

  [1] ftbench -t 5 -p -s 14 -b a -f 0008 Arial.ttf
  [2] ftbench -t 5 -p -s 14 -b a -r 1 -f 0028 Arial.ttf
  [3] ftbench -t 5 -p -s 14 -b a -f 000a Arial.ttf
  [4] ftbench -t 5 -p -s 14 -b b -f 0008 Arial.ttf

* builds/unix/ftconfig.in, include/freetype/config/ftconfig.h
(FT_MULFIX_ASSEMBLER): Fix handling for ARMv7.
2013-07-16 13:19:32 +02:00
..
freetype Speed up ARMv7 support. 2013-07-16 13:19:32 +02:00
ft2build.h Normalize quotation to `...'. 2006-03-24 12:46:49 +00:00