Add openmax dl routines for review. MUST NOT BE LANDED

third_party/openmax_dl/dl/sp/src/armSP_FFT_CToC_FC32_Radix2_fs_unsafe_s.S

+@//
+@//  Copyright (c) 2013 The WebRTC project authors. All Rights Reserved.
+@//
+@//  Use of this source code is governed by a BSD-style license
+@//  that can be found in the LICENSE file in the root of the source
+@//  tree. An additional intellectual property rights grant can be found
+@//  in the file PATENTS.  All contributing project authors may
+@//  be found in the AUTHORS file in the root of the source tree.
+@//
+@//  This is a modification of armSP_FFT_CToC_SC32_Radix2_fs_unsafe_s.S
+@//  to support float instead of SC32.
+@//
+
+@//
+@// Description:
+@// Compute the first stage of a Radix 2 DIT in-order out-of-place FFT
+@// stage for a N point complex signal.
+@//
+@//
+
+
+@// Include standard headers
+
+#include "dl/api/armCOMM_s.h"
+#include "dl/api/omxtypes_s.h"
+
+
+@// Import symbols required from other files
+@// (For example tables)
+
+
+
+
+@// Set debugging level
+@//DEBUG_ON    SETL {TRUE}
+
+
+
+@// Guarding implementation by the processor name
+
+
+
+@// Guarding implementation by the processor name
+
+
+@//Input Registers
+
+#define pSrc            r0
+#define pDst            r2
+#define pTwiddle        r1
+#define pPingPongBuf    r5
+#define subFFTNum       r6
+#define subFFTSize      r7
+
+
+@//Output Registers
+
+
+@//Local Scratch Registers
+
+#define pointStep       r3
+#define outPointStep    r3
+#define grpSize         r4
+#define setCount        r4
+#define step            r8
+#define dstStep         r8
+
+@// Neon Registers
+
+#define dX0     D0.F32
+#define dX1     D1.F32
+#define dY0     D2.F32
+#define dY1     D3.F32
+
+
+        .MACRO FFTSTAGE scaled, inverse, name
+
+        @// Define stack arguments
+
+
+        @// update subFFTSize and subFFTNum into RN6 and RN7 for the next stage
+
+
+        MOV        subFFTSize,#2
+        LSR        grpSize,subFFTNum,#1
+        MOV        subFFTNum,grpSize
+
+
+        @// pT0+1 increments pT0 by 8 bytes
+        @// pT0+pointStep = increment of 8*pointStep bytes = 4*grpSize bytes
+        @// Note: outPointStep = pointStep for firststage
+        @// Note: setCount = grpSize/2 (reuse the updated grpSize for setCount)
+
+        MOV        pointStep,grpSize,LSL #3
+        RSB        step,pointStep,#8
+
+
+        @// Loop on the sets for grp zero
+
+grpZeroSetLoop\name :
+
+        VLD1    dX0,[pSrc],pointStep
+        VLD1    dX1,[pSrc],step                   @// step = -pointStep + 8
+        SUBS    setCount,setCount,#1
+
+        VADD    dY0,dX0,dX1
+        VSUB    dY1,dX0,dX1
+
+        VST1    dY0,[pDst],outPointStep
+        @// dstStep =  step = -pointStep + 8
+        VST1    dY1,[pDst],dstStep
+
+        BGT     grpZeroSetLoop\name
+
+
+        @// reset pSrc to pDst for the next stage
+        SUB     pSrc,pDst,pointStep                     @// pDst -= 2*grpSize
+        MOV     pDst,pPingPongBuf
+
+        .endm
+
+
+
+        M_START armSP_FFTFwd_CToC_FC32_Radix2_fs_OutOfPlace_unsafe,r4
+        FFTSTAGE "FALSE","FALSE",fwd
+        M_END
+
+
+
+        M_START armSP_FFTInv_CToC_FC32_Radix2_fs_OutOfPlace_unsafe,r4
+        FFTSTAGE "FALSE","TRUE",inv
+        M_END
+
+        .end