1 // Copyright 2023 The Go Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style 3 // license that can be found in the LICENSE file. 4 5 // Macros for transitioning from the host ABI to Go ABI 6 // 7 // On PPC64/ELFv2 targets, the following registers are callee 8 // saved when called from C. They must be preserved before 9 // calling into Go which does not preserve any of them. 10 // 11 // R14-R31 12 // CR2-4 13 // VR20-31 14 // F14-F31 15 // 16 // xcoff(aix) and ELFv1 are similar, but may only require a 17 // subset of these. 18 // 19 // These macros assume a 16 byte aligned stack pointer. This 20 // is required by ELFv1, ELFv2, and AIX PPC64. 21 22 #define SAVE_GPR_SIZE (18*8) 23 #define SAVE_GPR(offset) \ 24 MOVD R14, (offset+8*0)(R1) \ 25 MOVD R15, (offset+8*1)(R1) \ 26 MOVD R16, (offset+8*2)(R1) \ 27 MOVD R17, (offset+8*3)(R1) \ 28 MOVD R18, (offset+8*4)(R1) \ 29 MOVD R19, (offset+8*5)(R1) \ 30 MOVD R20, (offset+8*6)(R1) \ 31 MOVD R21, (offset+8*7)(R1) \ 32 MOVD R22, (offset+8*8)(R1) \ 33 MOVD R23, (offset+8*9)(R1) \ 34 MOVD R24, (offset+8*10)(R1) \ 35 MOVD R25, (offset+8*11)(R1) \ 36 MOVD R26, (offset+8*12)(R1) \ 37 MOVD R27, (offset+8*13)(R1) \ 38 MOVD R28, (offset+8*14)(R1) \ 39 MOVD R29, (offset+8*15)(R1) \ 40 MOVD g, (offset+8*16)(R1) \ 41 MOVD R31, (offset+8*17)(R1) 42 43 #define RESTORE_GPR(offset) \ 44 MOVD (offset+8*0)(R1), R14 \ 45 MOVD (offset+8*1)(R1), R15 \ 46 MOVD (offset+8*2)(R1), R16 \ 47 MOVD (offset+8*3)(R1), R17 \ 48 MOVD (offset+8*4)(R1), R18 \ 49 MOVD (offset+8*5)(R1), R19 \ 50 MOVD (offset+8*6)(R1), R20 \ 51 MOVD (offset+8*7)(R1), R21 \ 52 MOVD (offset+8*8)(R1), R22 \ 53 MOVD (offset+8*9)(R1), R23 \ 54 MOVD (offset+8*10)(R1), R24 \ 55 MOVD (offset+8*11)(R1), R25 \ 56 MOVD (offset+8*12)(R1), R26 \ 57 MOVD (offset+8*13)(R1), R27 \ 58 MOVD (offset+8*14)(R1), R28 \ 59 MOVD (offset+8*15)(R1), R29 \ 60 MOVD (offset+8*16)(R1), g \ 61 MOVD (offset+8*17)(R1), R31 62 63 #define SAVE_FPR_SIZE (18*8) 64 #define SAVE_FPR(offset) \ 65 FMOVD F14, (offset+8*0)(R1) \ 66 FMOVD F15, (offset+8*1)(R1) \ 67 FMOVD F16, (offset+8*2)(R1) \ 68 FMOVD F17, (offset+8*3)(R1) \ 69 FMOVD F18, (offset+8*4)(R1) \ 70 FMOVD F19, (offset+8*5)(R1) \ 71 FMOVD F20, (offset+8*6)(R1) \ 72 FMOVD F21, (offset+8*7)(R1) \ 73 FMOVD F22, (offset+8*8)(R1) \ 74 FMOVD F23, (offset+8*9)(R1) \ 75 FMOVD F24, (offset+8*10)(R1) \ 76 FMOVD F25, (offset+8*11)(R1) \ 77 FMOVD F26, (offset+8*12)(R1) \ 78 FMOVD F27, (offset+8*13)(R1) \ 79 FMOVD F28, (offset+8*14)(R1) \ 80 FMOVD F29, (offset+8*15)(R1) \ 81 FMOVD F30, (offset+8*16)(R1) \ 82 FMOVD F31, (offset+8*17)(R1) 83 84 #define RESTORE_FPR(offset) \ 85 FMOVD (offset+8*0)(R1), F14 \ 86 FMOVD (offset+8*1)(R1), F15 \ 87 FMOVD (offset+8*2)(R1), F16 \ 88 FMOVD (offset+8*3)(R1), F17 \ 89 FMOVD (offset+8*4)(R1), F18 \ 90 FMOVD (offset+8*5)(R1), F19 \ 91 FMOVD (offset+8*6)(R1), F20 \ 92 FMOVD (offset+8*7)(R1), F21 \ 93 FMOVD (offset+8*8)(R1), F22 \ 94 FMOVD (offset+8*9)(R1), F23 \ 95 FMOVD (offset+8*10)(R1), F24 \ 96 FMOVD (offset+8*11)(R1), F25 \ 97 FMOVD (offset+8*12)(R1), F26 \ 98 FMOVD (offset+8*13)(R1), F27 \ 99 FMOVD (offset+8*14)(R1), F28 \ 100 FMOVD (offset+8*15)(R1), F29 \ 101 FMOVD (offset+8*16)(R1), F30 \ 102 FMOVD (offset+8*17)(R1), F31 103 104 // Save and restore VR20-31 (aka VSR56-63). These 105 // macros must point to a 16B aligned offset. 106 #define SAVE_VR_SIZE (12*16) 107 #define SAVE_VR(offset, rtmp) \ 108 MOVD $(offset+16*0), rtmp \ 109 STVX V20, (rtmp)(R1) \ 110 MOVD $(offset+16*1), rtmp \ 111 STVX V21, (rtmp)(R1) \ 112 MOVD $(offset+16*2), rtmp \ 113 STVX V22, (rtmp)(R1) \ 114 MOVD $(offset+16*3), rtmp \ 115 STVX V23, (rtmp)(R1) \ 116 MOVD $(offset+16*4), rtmp \ 117 STVX V24, (rtmp)(R1) \ 118 MOVD $(offset+16*5), rtmp \ 119 STVX V25, (rtmp)(R1) \ 120 MOVD $(offset+16*6), rtmp \ 121 STVX V26, (rtmp)(R1) \ 122 MOVD $(offset+16*7), rtmp \ 123 STVX V27, (rtmp)(R1) \ 124 MOVD $(offset+16*8), rtmp \ 125 STVX V28, (rtmp)(R1) \ 126 MOVD $(offset+16*9), rtmp \ 127 STVX V29, (rtmp)(R1) \ 128 MOVD $(offset+16*10), rtmp \ 129 STVX V30, (rtmp)(R1) \ 130 MOVD $(offset+16*11), rtmp \ 131 STVX V31, (rtmp)(R1) 132 133 #define RESTORE_VR(offset, rtmp) \ 134 MOVD $(offset+16*0), rtmp \ 135 LVX (rtmp)(R1), V20 \ 136 MOVD $(offset+16*1), rtmp \ 137 LVX (rtmp)(R1), V21 \ 138 MOVD $(offset+16*2), rtmp \ 139 LVX (rtmp)(R1), V22 \ 140 MOVD $(offset+16*3), rtmp \ 141 LVX (rtmp)(R1), V23 \ 142 MOVD $(offset+16*4), rtmp \ 143 LVX (rtmp)(R1), V24 \ 144 MOVD $(offset+16*5), rtmp \ 145 LVX (rtmp)(R1), V25 \ 146 MOVD $(offset+16*6), rtmp \ 147 LVX (rtmp)(R1), V26 \ 148 MOVD $(offset+16*7), rtmp \ 149 LVX (rtmp)(R1), V27 \ 150 MOVD $(offset+16*8), rtmp \ 151 LVX (rtmp)(R1), V28 \ 152 MOVD $(offset+16*9), rtmp \ 153 LVX (rtmp)(R1), V29 \ 154 MOVD $(offset+16*10), rtmp \ 155 LVX (rtmp)(R1), V30 \ 156 MOVD $(offset+16*11), rtmp \ 157 LVX (rtmp)(R1), V31 158 159 // LR and CR are saved in the caller's frame. The callee must 160 // make space for all other callee-save registers. 161 #define SAVE_ALL_REG_SIZE (SAVE_GPR_SIZE+SAVE_FPR_SIZE+SAVE_VR_SIZE) 162 163 // Stack a frame and save all callee-save registers following the 164 // host OS's ABI. Fortunately, this is identical for AIX, ELFv1, and 165 // ELFv2. All host ABIs require the stack pointer to maintain 16 byte 166 // alignment, and save the callee-save registers in the same places. 167 // 168 // To restate, R1 is assumed to be aligned when this macro is used. 169 // This assumes the caller's frame is compliant with the host ABI. 170 // CR and LR are saved into the caller's frame per the host ABI. 171 // R0 is initialized to $0 as expected by Go. 172 #define STACK_AND_SAVE_HOST_TO_GO_ABI(extra) \ 173 MOVD LR, R0 \ 174 MOVD R0, 16(R1) \ 175 MOVW CR, R0 \ 176 MOVD R0, 8(R1) \ 177 MOVDU R1, -(extra)-FIXED_FRAME-SAVE_ALL_REG_SIZE(R1) \ 178 SAVE_GPR(extra+FIXED_FRAME) \ 179 SAVE_FPR(extra+FIXED_FRAME+SAVE_GPR_SIZE) \ 180 SAVE_VR(extra+FIXED_FRAME+SAVE_GPR_SIZE+SAVE_FPR_SIZE, R0) \ 181 MOVD $0, R0 182 183 // This unstacks the frame, restoring all callee-save registers 184 // as saved by STACK_AND_SAVE_HOST_TO_GO_ABI. 185 // 186 // R0 is not guaranteed to contain $0 after this macro. 187 #define UNSTACK_AND_RESTORE_GO_TO_HOST_ABI(extra) \ 188 RESTORE_GPR(extra+FIXED_FRAME) \ 189 RESTORE_FPR(extra+FIXED_FRAME+SAVE_GPR_SIZE) \ 190 RESTORE_VR(extra+FIXED_FRAME+SAVE_GPR_SIZE+SAVE_FPR_SIZE, R0) \ 191 ADD $(extra+FIXED_FRAME+SAVE_ALL_REG_SIZE), R1 \ 192 MOVD 16(R1), R0 \ 193 MOVD R0, LR \ 194 MOVD 8(R1), R0 \ 195 MOVW R0, CR 196