diff --git a/webrtc/build/generate_asm_header.gypi b/webrtc/build/generate_asm_header.gypi
index f470288b76..4600bb19a9 100644
--- a/webrtc/build/generate_asm_header.gypi
+++ b/webrtc/build/generate_asm_header.gypi
@@ -32,6 +32,21 @@
   'variables': {
     'out_dir': '<(SHARED_INTERMEDIATE_DIR)/<(asm_header_dir)',
     'process_outputs_as_sources': 1,
+    'conditions': [
+      # We only support Android and iOS.
+      ['OS=="android"', {
+        'compiler_to_use':
+          '<!(/bin/echo -n ${ANDROID_GOMA_WRAPPER} <(android_toolchain)/*-gcc)',
+        'compiler_options': '-I<(webrtc_root)/.. -I<@(android_ndk_include) -S',
+        'pattern_to_detect': 'offset_',
+      }],
+      ['OS=="ios"', {
+        'compiler_to_use': 'clang',
+        'compiler_options':
+          '-arch armv7 -I<(webrtc_root)/.. -isysroot $(SDKROOT) -S',
+        'pattern_to_detect': '_offset_',
+      }],
+    ]
   },
   'rules': [
     {
@@ -46,10 +61,9 @@
       'action': [
         'python',
         '<(webrtc_root)/build/generate_asm_header.py',
-        '--compiler=<!(/bin/echo -n ${ANDROID_GOMA_WRAPPER} '
-          '<(android_toolchain)/*-gcc)',
-        # Compiler options.
-        '--options=-I<(webrtc_root)/.. -I<@(android_ndk_include) -S',
+        '--compiler=<(compiler_to_use)',
+        '--options=<(compiler_options)',
+        '--pattern=<(pattern_to_detect)',
         '--dir=<(out_dir)',
         '<(RULE_INPUT_PATH)',
       ],
diff --git a/webrtc/build/generate_asm_header.py b/webrtc/build/generate_asm_header.py
index 28b2737d7c..c159d50741 100644
--- a/webrtc/build/generate_asm_header.py
+++ b/webrtc/build/generate_asm_header.py
@@ -19,8 +19,9 @@ and writes them into header files.
 """
 
 import os
-import sys
+import re
 import subprocess
+import sys
 from optparse import OptionParser
 
 def main(argv):
@@ -44,6 +45,7 @@ def main(argv):
   # Set the shell command with the compiler and options inputs.
   compiler_command = (options.compiler + " " + options.options + " " +
       input_filename + " -o " + interim_filename)
+
   # Run the shell command and generate the intermediate file.
   subprocess.check_call(compiler_command, shell=True)
 
@@ -51,13 +53,19 @@ def main(argv):
   out_file = open(out_filename, 'w')  # The output header file.
 
   # Generate the output header file.
-  for line in interim_file:  # Iterate though all the lines in the input file.
+  while True:
+    line = interim_file.readline()
+    if not line: break
     if line.startswith(options.pattern):
-      out_file.write('#define ')
-      out_file.write(line.split(':')[0])  # Write the constant name.
-      out_file.write(' ')
-    if line.find('.word') >= 0:
-      out_file.write(line.split('.word')[1])  # Write the constant value.
+      # Find name of the next constant and write to the output file.
+      const_name = re.sub(r'^_', '', line.split(':')[0])
+      out_file.write('#define %s ' % const_name)
+
+      # Find value of the constant we just found and write to the output file.
+      line = interim_file.readline()
+      const_value = filter(str.isdigit, line.split(' ')[0])
+      if const_value != '':
+        out_file.write('%s\n' % const_value)
 
   interim_file.close()
   out_file.close()
diff --git a/webrtc/modules/audio_processing/aecm/aecm_core_neon.S b/webrtc/modules/audio_processing/aecm/aecm_core_neon.S
index 65db08e3fe..1a06312c32 100644
--- a/webrtc/modules/audio_processing/aecm/aecm_core_neon.S
+++ b/webrtc/modules/audio_processing/aecm/aecm_core_neon.S
@@ -28,7 +28,7 @@ GLOBAL_FUNCTION WebRtcAecm_ResetAdaptiveChannelNeon
 @                                  const WebRtc_Word16* time_signal,
 @                                  complex16_t* freq_signal,
 @                                  int time_signal_scaling);
-.align  2
+.align 2
 DEFINE_FUNCTION WebRtcAecm_WindowAndFFTNeon
   push {r4, r5, r6, lr}
 
@@ -60,12 +60,12 @@ LOOP_PART_LEN:
   bgt LOOP_PART_LEN
 
   @ WebRtcSpl_RealForwardFFT(aecm->real_fft, fft, (int16_t*)freq_signal);
-  ldr r12, =offset_aecm_real_fft
+  movw r12, #offset_aecm_real_fft
   sub r1, #(PART_LEN * 4)                    @ Get r1 back to &fft[0].
   mov r2, r3                                 @ freq_signal
   mov r4, r3
   ldr r0, [r0, r12]                          @ aecm->real_fft
-  bl  WebRtcSpl_RealForwardFFTNeon
+  CALL_FUNCTION WebRtcSpl_RealForwardFFTNeon
 
   mov r12, #(PART_LEN * 2 / 16)              @ Loop counter, unrolled by 16.
 
@@ -85,7 +85,7 @@ LOOP_PART_LEN2:
 @                                         complex16_t* efw,
 @                                         WebRtc_Word16* output,
 @                                         const WebRtc_Word16* nearendClean);
-.align  2
+.align 2
 DEFINE_FUNCTION WebRtcAecm_InverseFFTAndWindowNeon
   push {r4-r8, lr}
 
@@ -119,15 +119,15 @@ LOOP_PRE_IFFT:
   str r8, [r4, r3]
 
   @ outCFFT = WebRtcSpl_RealInverseFFT(aecm->real_fft, fft, (int16_t*)efw);
-  ldr r12, =offset_aecm_real_fft
+  movw r12, #offset_aecm_real_fft
   sub r1, #(PART_LEN * 4)                    @ Get r1 back to &fft[0].
   sub r2, #(PART_LEN * 4)                    @ Get r2 back to &efw[0].
   mov r4, r2                                 @ Keep efw in r4.
   ldr r0, [r0, r12]                          @ aecm->real_fft
-  bl  WebRtcSpl_RealInverseFFTNeon
+  CALL_FUNCTION WebRtcSpl_RealInverseFFTNeon
 
-  ldr r6, =offset_aecm_outBuf
-  ldr r12, =offset_aecm_dfaCleanQDomain
+  movw r6, #offset_aecm_outBuf
+  movw r12, #offset_aecm_dfaCleanQDomain
   ldr r8, [r5, r6]                           @ &aecm->outBuf[0]
   ldrsh r2, [r5, r12]                        @ &aecm->dfaCleanQDomain[0]
 
@@ -160,8 +160,8 @@ LOOP_POST_IFFT:
   vst1.16 d0, [r8, :64]!                     @ aecm->outBuf[i]
   bgt LOOP_POST_IFFT
 
-  ldr r3, =offset_aecm_xBuf
-  ldr r12, =offset_aecm_dBufNoisy
+  movw r3, #offset_aecm_xBuf
+  movw r12, #offset_aecm_dBufNoisy
   ldr r3, [r5, r3]                           @ &aecm->xBuf[0]
   ldr r1, [r5, r12]                          @ &aecm->dBufNoisy[0]
   add r2, r3, #(PART_LEN * 2)                @ &aecm->xBuf[PART_LEN]
@@ -180,7 +180,7 @@ LOOP_COPY:
   cmp r2, #0                                  @ Check if (nearendClean != NULL).
   beq END
 
-  ldr r4, =offset_aecm_dBufClean
+  movw r4, #offset_aecm_dBufClean
   ldr r1, [r5, r4]                            @ &aecm->dBufClean[0]
   add r0, r1, #(PART_LEN * 2)                 @ &aecm->dBufClean[PART_LEN]
 
@@ -202,7 +202,7 @@ END:
 @                                        WebRtc_UWord32* far_energy,
 @                                        WebRtc_UWord32* echo_energy_adapt,
 @                                        WebRtc_UWord32* echo_energy_stored);
-.align  2
+.align 2
 DEFINE_FUNCTION WebRtcAecm_CalcLinearEnergiesNeon
   push {r4-r7}
 
@@ -210,8 +210,8 @@ DEFINE_FUNCTION WebRtcAecm_CalcLinearEnergiesNeon
   vmov.i32 q8,  #0
   vmov.i32 q9,  #0
 
-  ldr r7, =offset_aecm_channelStored
-  ldr r5, =offset_aecm_channelAdapt16
+  movw r7, #offset_aecm_channelStored
+  movw r5, #offset_aecm_channelAdapt16
 
   mov r4, r2
   mov r12, #(PART_LEN / 8)                   @  Loop counter, unrolled by 8.
@@ -267,10 +267,10 @@ LOOP_CALC_LINEAR_ENERGIES:
 @ void WebRtcAecm_StoreAdaptiveChannelNeon(AecmCore_t* aecm,
 @                                          const uint16_t* far_spectrum,
 @                                          int32_t* echo_est);
-.align  2
+.align 2
 DEFINE_FUNCTION WebRtcAecm_StoreAdaptiveChannelNeon
-  ldr r3, =offset_aecm_channelAdapt16
-  ldr r12, =offset_aecm_channelStored
+  movw r3, #offset_aecm_channelAdapt16
+  movw r12, #offset_aecm_channelStored
   ldr r3, [r0, r3]
   ldr r0, [r0, r12]
   mov r12, #(PART_LEN / 8)                   @ Loop counter, unrolled by 8.
@@ -294,10 +294,10 @@ LOOP_STORE_ADAPTIVE_CHANNEL:
   bx  lr
 
 @ void WebRtcAecm_ResetAdaptiveChannelNeon(AecmCore_t* aecm);
-.align  2
+.align 2
 DEFINE_FUNCTION WebRtcAecm_ResetAdaptiveChannelNeon
-  ldr r1, =offset_aecm_channelAdapt16
-  ldr r2, =offset_aecm_channelAdapt32
+  movw r1, #offset_aecm_channelAdapt16
+  movw r2, #offset_aecm_channelAdapt32
   movw r3, #offset_aecm_channelStored
   ldr r1, [r0, r1]                           @ &aecm->channelAdapt16[0]
   ldr r2, [r0, r2]                           @ &aecm->channelAdapt32[0]
@@ -321,8 +321,9 @@ LOOP_RESET_ADAPTIVE_CHANNEL:
   bx  lr
 
 @ Square root of Hanning window in Q14.
-.align 3
+.align 4
 WebRtcAecm_kSqrtHanning:
+_WebRtcAecm_kSqrtHanning:
   .short 0
   .short 399, 798, 1196, 1594, 1990, 2386, 2780, 3172
   .short 3562, 3951, 4337, 4720, 5101, 5478, 5853, 6224
@@ -335,7 +336,7 @@ WebRtcAecm_kSqrtHanning:
 
 @ Square root of Hanning window in Q14. Compared to WebRtcAecm_kSqrtHanning,
 @ the order was reversed and one element (0) was removed.
-.align  3
+.align 4
 kSqrtHanningReversed:
   .short 16384, 16373, 16354, 16325, 16286, 16237, 16179, 16111, 16034, 15947
   .short 15851, 15746, 15631, 15506, 15373, 15231, 15079, 14918, 14749, 14571
diff --git a/webrtc/modules/audio_processing/audio_processing.gypi b/webrtc/modules/audio_processing/audio_processing.gypi
index 00eb28a1ec..c6a7265851 100644
--- a/webrtc/modules/audio_processing/audio_processing.gypi
+++ b/webrtc/modules/audio_processing/audio_processing.gypi
@@ -174,11 +174,10 @@
           'ns/nsx_core_neon.c',
         ],
         'conditions': [
-          ['OS=="android"', {
+          ['OS=="android" or OS=="ios"', {
             'dependencies': [
               'audio_processing_offsets',
             ],
-            # TODO(kma): port this block from Android into other build systems.
             'sources': [
               'aecm/aecm_core_neon.S',
               'ns/nsx_core_neon.S',
@@ -192,7 +191,7 @@
         ],
       }],
       'conditions': [
-        ['OS=="android"', {
+        ['OS=="android" or OS=="ios"', {
           'targets': [{
             'target_name': 'audio_processing_offsets',
             'type': 'none',
diff --git a/webrtc/modules/audio_processing/ns/nsx_core_neon.S b/webrtc/modules/audio_processing/ns/nsx_core_neon.S
index ccea6ad068..fb3e9f3c4a 100644
--- a/webrtc/modules/audio_processing/ns/nsx_core_neon.S
+++ b/webrtc/modules/audio_processing/ns/nsx_core_neon.S
@@ -26,7 +26,9 @@ GLOBAL_LABEL WebRtcNsx_kLogTable
 GLOBAL_LABEL WebRtcNsx_kCounterDiv
 GLOBAL_LABEL WebRtcNsx_kLogTableFrac
 
+.align 2
 WebRtcNsx_kLogTableFrac:
+_WebRtcNsx_kLogTableFrac:
 .short 0, 1, 3, 4, 6, 7, 9, 10, 11, 13, 14, 16, 17, 18, 20, 21, 22, 24, 25, 26
 .short 28, 29, 30, 32, 33, 34, 36, 37, 38, 40, 41, 42, 44, 45, 46, 47, 49, 50
 .short 51, 52, 54, 55, 56, 57, 59, 60, 61, 62, 63, 65, 66, 67, 68, 69, 71, 72
@@ -45,7 +47,9 @@ WebRtcNsx_kLogTableFrac:
 .short 244, 245, 246, 247, 247, 248, 249, 249, 250, 251, 252, 252, 253, 254, 255
 .short 255
 
+.align 2
 WebRtcNsx_kCounterDiv:
+_WebRtcNsx_kCounterDiv:
 .short 32767, 16384, 10923, 8192, 6554, 5461, 4681, 4096, 3641, 3277, 2979
 .short 2731, 2521, 2341, 2185, 2048, 1928, 1820, 1725, 1638, 1560, 1489
 .short 1425, 1365, 1311, 1260, 1214, 1170, 1130, 1092, 1057, 1024, 993, 964
@@ -62,7 +66,9 @@ WebRtcNsx_kCounterDiv:
 .short 187, 186, 185, 184, 183, 182, 181, 180, 179, 178, 177, 176, 175, 174
 .short 173, 172, 172, 171, 170, 169, 168, 167, 166, 165, 165, 164, 163
 
+.align 2
 WebRtcNsx_kLogTable:
+_WebRtcNsx_kLogTable:
 .short  0, 177, 355, 532, 710, 887, 1065, 1242, 1420
 
 @ void NoiseEstimationNeon(NsxInst_t* inst,
@@ -82,6 +88,7 @@ WebRtcNsx_kLogTable:
 @ r11: countDiv
 @ r12: i, the loop counter for LOOP_NOISEESTIMATION_MAGNLEN_INNER
 
+.align 2
 DEFINE_FUNCTION WebRtcNsx_NoiseEstimationNeon
   push {r4-r11, r14}
   vpush {d8-d15}
@@ -146,7 +153,8 @@ CHECK_LMAGN_COUNTER:
   ldr r7, [r0, r7]
   add r9, r0
   cmp r7, #END_STARTUP_LONG
-  add r10, r0, #offset_nsx_noiseEstCounter
+  movw r10, #offset_nsx_noiseEstCounter
+  add r10, r0
   movge r7, #FACTOR_Q7
   movlt r7, #FACTOR_Q7_STARTUP
   mov r4, r0
@@ -307,7 +315,7 @@ UPDATE_DENSITY_ESTIMATE_CHECK_COUNTER:
 
   mov r0, r4
   mov r1, r7
-  bl UpdateNoiseEstimateNeon
+  CALL_FUNCTION UpdateNoiseEstimateNeon
 
 POST_UPDATE_DENSITY_ESTIMATE:
   ldrh r3, [r10]
@@ -324,7 +332,7 @@ POST_UPDATE_DENSITY_ESTIMATE:
 
   sub r1, r7, r6
   mov r0, r4
-  bl UpdateNoiseEstimateNeon
+  CALL_FUNCTION UpdateNoiseEstimateNeon
 
 UPDATE_NOISE:
   movw r1, #offset_nsx_noiseEstQuantile
@@ -350,6 +358,7 @@ UPDATE_Q_NOISE:
 
 @ static void UpdateNoiseEstimateNeon(NsxInst_t* inst, int offset);
 @ Neon registers touched: q0-q3, q8-q13.
+.align 2
 DEFINE_FUNCTION UpdateNoiseEstimateNeon
   push {r4, r5, r6, r14}
   mov r5, r0
@@ -366,7 +375,7 @@ DEFINE_FUNCTION UpdateNoiseEstimateNeon
 
   mov r0, r4
   mov r1, r6
-  bl WebRtcSpl_MaxValueW16Neon
+  CALL_FUNCTION WebRtcSpl_MaxValueW16Neon
 
   sub r12, r6, #1             @ Loop counter: inst->magnLen - 1.
 
@@ -418,6 +427,7 @@ POST_LOOP_MAGNLEN:
   pop {r4, r5, r6, pc}
 
 @ void PrepareSpectrumNeon(NsxInst_t* inst, int16_t* freq_buf);
+.align 2
 DEFINE_FUNCTION WebRtcNsx_PrepareSpectrumNeon
   push {r4-r8}
 
@@ -533,6 +543,7 @@ LOOP_ANALEN2:
   bx r14
 
 @ void WebRtcNsx_DenormalizeNeon(NsxInst_t* inst, int16_t* in, int factor);
+.align 2
 DEFINE_FUNCTION WebRtcNsx_DenormalizeNeon
   movw r12, #offset_nsx_normData
   movw r3, #offset_nsx_real
@@ -563,6 +574,7 @@ LOOP_ANALEN:
 @ void SynthesisUpdateNeon(NsxInst_t* inst,
 @                          int16_t* out_frame,
 @                          int16_t gain_factor);
+.align 2
 DEFINE_FUNCTION WebRtcNsx_SynthesisUpdateNeon
   push {r4, r5}
 
@@ -635,6 +647,7 @@ EXIT_SYNTHESISUPDATE:
   bx r14
 
 @ void AnalysisUpdateNeon(NsxInst_t* inst, int16_t* out, int16_t* new_speech);
+.align 2
 DEFINE_FUNCTION WebRtcNsx_AnalysisUpdateNeon
   push {r4-r6}
 
@@ -693,6 +706,7 @@ POST_LOOP_WINDOW_DATA:
   bx r14
 
 @ void CreateComplexBufferNeon(NsxInst_t* inst, int16_t* in, int16_t* out);
+.align 2
 DEFINE_FUNCTION WebRtcNsx_CreateComplexBufferNeon
   movw r3, #offset_nsx_anaLen
   movw r12, #offset_nsx_normData
diff --git a/webrtc/system_wrappers/interface/asm_defines.h b/webrtc/system_wrappers/interface/asm_defines.h
index 49a12e1613..c0fc5cbd1b 100644
--- a/webrtc/system_wrappers/interface/asm_defines.h
+++ b/webrtc/system_wrappers/interface/asm_defines.h
@@ -45,6 +45,15 @@ bl \name
 .endm
 #endif
 
+// With llvm and clang compilers, for instructions ldrb, strh, etc.,
+// the condition code is after the width specifier. Here we define
+// only the ones that are actually used in the assembly files.
+#ifdef __llvm__
+.macro streqh reg1, reg2, num
+strheq \reg1, \reg2, \num
+.endm
+#endif
+
 .text
 
 #endif  // WEBRTC_SYSTEM_WRAPPERS_INTERFACE_COMPILE_ASSERT_H_