1 // 2 // Copyright (c) 2013 The WebRTC project authors. All Rights Reserved. 3 // 4 // Use of this source code is governed by a BSD-style license 5 // that can be found in the LICENSE file in the root of the source 6 // tree. An additional intellectual property rights grant can be found 7 // in the file PATENTS. All contributing project authors may 8 // be found in the AUTHORS file in the root of the source tree. 9 // 10 // This is a modification of armSP_FFT_CToC_SC32_Radix2_fs_unsafe_s.S 11 // to support float instead of SC32. 12 // 13 14 // 15 // Description: 16 // Compute the first stage of a Radix 2 DIT in-order out-of-place FFT 17 // stage for a N point complex signal. 18 // 19 // 20 21 22 // Include standard headers 23 24 #include "dl/api/arm/arm64COMM_s.h" 25 #include "dl/api/arm/omxtypes_s.h" 26 27 28 // Import symbols required from other files 29 // (For example tables) 30 31 32 33 34 // Set debugging level 35 //DEBUG_ON SETL {TRUE} 36 37 38 39 // Guarding implementation by the processor name 40 41 42 43 // Guarding implementation by the processor name 44 45 46 //Input Registers 47 48 #define pSrc x0 49 #define pDst x1 50 #define pTwiddle x2 51 #define pSubFFTNum x3 52 #define pSubFFTSize x4 53 54 55 //Output Registers 56 57 58 //Local Scratch Registers 59 60 #define subFFTNum x5 61 #define subFFTSize x6 62 #define pointStep x7 63 #define outPointStep x7 64 #define grpSize x8 65 #define setCount x8 66 #define step x9 67 #define dstStep x9 68 69 // Neon Registers 70 #define dX0 v0.2s 71 #define dX1 v1.2s 72 #define dY0 v2.2s 73 #define dY1 v3.2s 74 75 .macro FFTSTAGE scaled, inverse, name 76 77 // Define stack arguments 78 79 // Move args values into our work registers 80 ldr subFFTNum, [pSubFFTNum] 81 ldr subFFTSize, [pSubFFTSize] 82 83 // update subFFTSize and subFFTNum into RN6 and RN7 for the next stage 84 85 86 MOV subFFTSize,#2 87 LSR grpSize,subFFTNum,#1 88 MOV subFFTNum,grpSize 89 90 91 // pT0+1 increments pT0 by 8 bytes 92 // pT0+pointStep = increment of 8*pointStep bytes = 4*grpSize bytes 93 // Note: outPointStep = pointStep for firststage 94 // Note: setCount = grpSize/2 (reuse the updated grpSize for setCount) 95 96 lsl pointStep, grpSize, #3 97 rsb step, pointStep, #8 98 99 // Loop on the sets for grp zero 100 101 grpZeroSetLoop\name : 102 103 LD1 {dX0},[pSrc],pointStep 104 LD1 {dX1},[pSrc],step // step = -pointStep + 8 105 106 SUBS setCount,setCount,#1 107 108 fadd dY0,dX0,dX1 109 fsub dY1,dX0,dX1 110 111 ST1 {dY0},[pDst],outPointStep 112 // dstStep = step = -pointStep + 8 113 ST1 {dY1},[pDst],dstStep 114 115 BGT grpZeroSetLoop\name 116 117 118 // Save subFFTNum and subFFTSize for next stage 119 str subFFTNum, [pSubFFTNum] 120 str subFFTSize, [pSubFFTSize] 121 122 .endm 123 124 125 126 M_START armSP_FFTFwd_CToC_FC32_Radix2_fs_OutOfPlace 127 FFTSTAGE "FALSE","FALSE",fwd 128 M_END 129 130 131 132 M_START armSP_FFTInv_CToC_FC32_Radix2_fs_OutOfPlace 133 FFTSTAGE "FALSE","TRUE",inv 134 M_END 135 136 .end 137
