Use the ARM assembly code in mpi_arm.c for iOS.

nss/nss.gyp

Index: nss/nss.gyp
===================================================================
--- nss/nss.gyp	(revision 148841)
+++ nss/nss.gyp	(working copy)
@@ -574,6 +574,7 @@
         'mozilla/security/nss/lib/freebl/mpi/mpi.c',
         'mozilla/security/nss/lib/freebl/mpi/mpi.h',
         'mozilla/security/nss/lib/freebl/mpi/mpi_amd64.c',
+        'mozilla/security/nss/lib/freebl/mpi/mpi_arm.c',
         'mozilla/security/nss/lib/freebl/mpi/mpi_x86_asm.c',
         'mozilla/security/nss/lib/freebl/mpi/mplogic.c',
         'mozilla/security/nss/lib/freebl/mpi/mplogic.h',
@@ -1048,6 +1049,9 @@
           'sources/': [
             ['exclude', 'amd64'],
           ],
+          'sources!': [
+            'mozilla/security/nss/lib/freebl/mpi/mpi_arm.c',

[Ryan Sleevi, 2012/07/30 06:47:55]

nit: It would seem that either line 1050 should be moved to an explicit
sources!, or the sources! should exclude _arm files, since there is only one
platform-specific file for each (mpi_arm.c/mpi_amd64.c)

+          ],
         }],
         ['OS=="mac" or OS=="ios"', {
           'defines': [
@@ -1082,6 +1086,13 @@
               'NSS_X86_OR_X64',
               'NSS_X64',
             ],
+            'GCC_PREPROCESSOR_DEFINITIONS[arch=armv7]': [

[wtc, 2012/07/27 23:31:59]

Is this the right way to test for a build that targets
an iOS device (as opposed to the Simulator)?

+              '$(inherited)',
+              'MP_ASSEMBLY_MULTIPLY',
+              'MP_ASSEMBLY_SQUARE',
+              'MP_USE_UINT_DIGIT',
+              'SHA_NO_LONG_LONG',
+            ],
           },
         }],
         ['OS=="win"', {