gcc/config/aarch64/aarch64-modes.def

   1 /* Machine description for AArch64 architecture.
   2    Copyright (C) 2009-2022 Free Software Foundation, Inc.
   3    Contributed by ARM Ltd.
   4
   5    This file is part of GCC.
   6
   7    GCC is free software; you can redistribute it and/or modify it
   8    under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3, or (at your option)
  10    any later version.
  11
  12    GCC is distributed in the hope that it will be useful, but
  13    WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15    General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with GCC; see the file COPYING3.  If not see
  19    <http://www.gnu.org/licenses/>.  */
  20
  21 /* Important note about Carry generation in AArch64.
  22
  23    Unlike some architectures, the C flag generated by a subtract
  24    operation, or a simple compare operation is set to 1 if the result
  25    does not overflow in an unsigned sense.  That is, if there is no
  26    borrow needed from a higher word.  That means that overflow from
  27    addition will set C, but overflow from a subtraction will clear C.
  28    We use CC_Cmode to represent detection of overflow from addition as
  29    CCmode is used for 'normal' compare (subtraction) operations.  For
  30    ADC, the representation becomes more complex still, since we cannot
  31    use the normal idiom of comparing the result to one of the input
  32    operands; instead we use CC_ADCmode to represent this case.  */
  33 CC_MODE (CCFP);
  34 CC_MODE (CCFPE);
  35 CC_MODE (CC_SWP);
  36 CC_MODE (CC_NZC);   /* Only N, Z and C bits of condition flags are valid.
  37                        (Used with SVE predicate tests.)  */
  38 CC_MODE (CC_NZ);    /* Only N and Z bits of condition flags are valid.  */
  39 CC_MODE (CC_Z);     /* Only Z bit of condition flags is valid.  */
  40 CC_MODE (CC_C);     /* C represents unsigned overflow of a simple addition.  */
  41 CC_MODE (CC_ADC);   /* Unsigned overflow from an ADC (add with carry).  */
  42 CC_MODE (CC_V);     /* Only V bit of condition flags is valid.  */
  43
  44 /* Half-precision floating point for __fp16.  */
  45 FLOAT_MODE (HF, 2, 0);
  46 ADJUST_FLOAT_FORMAT (HF, &ieee_half_format);
  47
  48 /* Vector modes.  */
  49
  50 VECTOR_BOOL_MODE (VNx16BI, 16, 2);
  51 VECTOR_BOOL_MODE (VNx8BI, 8, 2);
  52 VECTOR_BOOL_MODE (VNx4BI, 4, 2);
  53 VECTOR_BOOL_MODE (VNx2BI, 2, 2);
  54
  55 ADJUST_NUNITS (VNx16BI, aarch64_sve_vg * 8);
  56 ADJUST_NUNITS (VNx8BI, aarch64_sve_vg * 4);
  57 ADJUST_NUNITS (VNx4BI, aarch64_sve_vg * 2);
  58 ADJUST_NUNITS (VNx2BI, aarch64_sve_vg);
  59
  60 ADJUST_ALIGNMENT (VNx16BI, 2);
  61 ADJUST_ALIGNMENT (VNx8BI, 2);
  62 ADJUST_ALIGNMENT (VNx4BI, 2);
  63 ADJUST_ALIGNMENT (VNx2BI, 2);
  64
  65 /* Bfloat16 modes.  */
  66 FLOAT_MODE (BF, 2, 0);
  67 ADJUST_FLOAT_FORMAT (BF, &arm_bfloat_half_format);
  68
  69 VECTOR_MODES (INT, 8);        /*       V8QI V4HI V2SI.  */
  70 VECTOR_MODES (INT, 16);       /* V16QI V8HI V4SI V2DI.  */
  71 VECTOR_MODES (FLOAT, 8);      /*                 V2SF.  */
  72 VECTOR_MODES (FLOAT, 16);     /*            V4SF V2DF.  */
  73 VECTOR_MODE (FLOAT, DF, 1);   /*                 V1DF.  */
  74 VECTOR_MODE (FLOAT, HF, 2);   /*                 V2HF.  */
  75
  76 /* Oct Int: 256-bit integer mode needed for 32-byte vector arguments.  */
  77 INT_MODE (OI, 32);
  78
  79 /* Opaque integer modes for 3 or 4 Neon q-registers / 6 or 8 Neon d-registers
  80    (2 d-regs = 1 q-reg = TImode).  */
  81 INT_MODE (CI, 48);
  82 INT_MODE (XI, 64);
  83
  84 /* V8DI mode.  */
  85 VECTOR_MODE_WITH_PREFIX (V, INT, DI, 8, 5);
  86
  87 ADJUST_ALIGNMENT (V8DI, 8);
  88
  89 /* Define Advanced SIMD modes for structures of 2, 3 and 4 d-registers.  */
  90 #define ADV_SIMD_D_REG_STRUCT_MODES(NVECS, VB, VH, VS, VD) \
  91   VECTOR_MODES_WITH_PREFIX (V##NVECS##x, INT, 8, 3); \
  92   VECTOR_MODES_WITH_PREFIX (V##NVECS##x, FLOAT, 8, 3); \
  93   VECTOR_MODE_WITH_PREFIX (V##NVECS##x, FLOAT, DF, 1, 3); \
  94   VECTOR_MODE_WITH_PREFIX (V##NVECS##x, INT, DI, 1, 3); \
  95   \
  96   ADJUST_NUNITS (VB##QI, NVECS * 8); \
  97   ADJUST_NUNITS (VH##HI, NVECS * 4); \
  98   ADJUST_NUNITS (VS##SI, NVECS * 2); \
  99   ADJUST_NUNITS (VD##DI, NVECS); \
 100   ADJUST_NUNITS (VH##BF, NVECS * 4); \
 101   ADJUST_NUNITS (VH##HF, NVECS * 4); \
 102   ADJUST_NUNITS (VS##SF, NVECS * 2); \
 103   ADJUST_NUNITS (VD##DF, NVECS); \
 104   \
 105   ADJUST_ALIGNMENT (VB##QI, 8); \
 106   ADJUST_ALIGNMENT (VH##HI, 8); \
 107   ADJUST_ALIGNMENT (VS##SI, 8); \
 108   ADJUST_ALIGNMENT (VD##DI, 8); \
 109   ADJUST_ALIGNMENT (VH##BF, 8); \
 110   ADJUST_ALIGNMENT (VH##HF, 8); \
 111   ADJUST_ALIGNMENT (VS##SF, 8); \
 112   ADJUST_ALIGNMENT (VD##DF, 8);
 113
 114 ADV_SIMD_D_REG_STRUCT_MODES (2, V2x8, V2x4, V2x2, V2x1)
 115 ADV_SIMD_D_REG_STRUCT_MODES (3, V3x8, V3x4, V3x2, V3x1)
 116 ADV_SIMD_D_REG_STRUCT_MODES (4, V4x8, V4x4, V4x2, V4x1)
 117
 118 /* Define Advanced SIMD modes for structures of 2, 3 and 4 q-registers.  */
 119 #define ADV_SIMD_Q_REG_STRUCT_MODES(NVECS, VB, VH, VS, VD) \
 120   VECTOR_MODES_WITH_PREFIX (V##NVECS##x, INT, 16, 3); \
 121   VECTOR_MODES_WITH_PREFIX (V##NVECS##x, FLOAT, 16, 3); \
 122   \
 123   ADJUST_NUNITS (VB##QI, NVECS * 16); \
 124   ADJUST_NUNITS (VH##HI, NVECS * 8); \
 125   ADJUST_NUNITS (VS##SI, NVECS * 4); \
 126   ADJUST_NUNITS (VD##DI, NVECS * 2); \
 127   ADJUST_NUNITS (VH##BF, NVECS * 8); \
 128   ADJUST_NUNITS (VH##HF, NVECS * 8); \
 129   ADJUST_NUNITS (VS##SF, NVECS * 4); \
 130   ADJUST_NUNITS (VD##DF, NVECS * 2); \
 131   \
 132   ADJUST_ALIGNMENT (VB##QI, 16); \
 133   ADJUST_ALIGNMENT (VH##HI, 16); \
 134   ADJUST_ALIGNMENT (VS##SI, 16); \
 135   ADJUST_ALIGNMENT (VD##DI, 16); \
 136   ADJUST_ALIGNMENT (VH##BF, 16); \
 137   ADJUST_ALIGNMENT (VH##HF, 16); \
 138   ADJUST_ALIGNMENT (VS##SF, 16); \
 139   ADJUST_ALIGNMENT (VD##DF, 16);
 140
 141 ADV_SIMD_Q_REG_STRUCT_MODES (2, V2x16, V2x8, V2x4, V2x2)
 142 ADV_SIMD_Q_REG_STRUCT_MODES (3, V3x16, V3x8, V3x4, V3x2)
 143 ADV_SIMD_Q_REG_STRUCT_MODES (4, V4x16, V4x8, V4x4, V4x2)
 144
 145 /* Define SVE modes for NVECS vectors.  VB, VH, VS and VD are the prefixes
 146    for 8-bit, 16-bit, 32-bit and 64-bit elements respectively.  It isn't
 147    strictly necessary to set the alignment here, since the default would
 148    be clamped to BIGGEST_ALIGNMENT anyhow, but it seems clearer.  */
 149 #define SVE_MODES(NVECS, VB, VH, VS, VD) \
 150   VECTOR_MODES_WITH_PREFIX (VNx, INT, 16 * NVECS, NVECS == 1 ? 1 : 4); \
 151   VECTOR_MODES_WITH_PREFIX (VNx, FLOAT, 16 * NVECS, NVECS == 1 ? 1 : 4); \
 152   \
 153   ADJUST_NUNITS (VB##QI, aarch64_sve_vg * NVECS * 8); \
 154   ADJUST_NUNITS (VH##HI, aarch64_sve_vg * NVECS * 4); \
 155   ADJUST_NUNITS (VS##SI, aarch64_sve_vg * NVECS * 2); \
 156   ADJUST_NUNITS (VD##DI, aarch64_sve_vg * NVECS); \
 157   ADJUST_NUNITS (VH##BF, aarch64_sve_vg * NVECS * 4); \
 158   ADJUST_NUNITS (VH##HF, aarch64_sve_vg * NVECS * 4); \
 159   ADJUST_NUNITS (VS##SF, aarch64_sve_vg * NVECS * 2); \
 160   ADJUST_NUNITS (VD##DF, aarch64_sve_vg * NVECS); \
 161   \
 162   ADJUST_ALIGNMENT (VB##QI, 16); \
 163   ADJUST_ALIGNMENT (VH##HI, 16); \
 164   ADJUST_ALIGNMENT (VS##SI, 16); \
 165   ADJUST_ALIGNMENT (VD##DI, 16); \
 166   ADJUST_ALIGNMENT (VH##BF, 16); \
 167   ADJUST_ALIGNMENT (VH##HF, 16); \
 168   ADJUST_ALIGNMENT (VS##SF, 16); \
 169   ADJUST_ALIGNMENT (VD##DF, 16);
 170
 171 /* Give SVE vectors the names normally used for 256-bit vectors.
 172    The actual number depends on command-line flags.  */
 173 SVE_MODES (1, VNx16, VNx8, VNx4, VNx2)
 174 SVE_MODES (2, VNx32, VNx16, VNx8, VNx4)
 175 SVE_MODES (3, VNx48, VNx24, VNx12, VNx6)
 176 SVE_MODES (4, VNx64, VNx32, VNx16, VNx8)
 177
 178 /* Partial SVE vectors:
 179
 180       VNx2QI VNx4QI VNx8QI
 181       VNx2HI VNx4HI
 182       VNx2SI
 183
 184    In memory they occupy contiguous locations, in the same way as fixed-length
 185    vectors.  E.g. VNx8QImode is half the size of VNx16QImode.
 186
 187    Passing 2 as the final argument ensures that the modes come after all
 188    other single-vector modes in the GET_MODE_WIDER chain, so that we never
 189    pick them in preference to a full vector mode.  */
 190 VECTOR_MODES_WITH_PREFIX (VNx, INT, 2, 2);
 191 VECTOR_MODES_WITH_PREFIX (VNx, INT, 4, 2);
 192 VECTOR_MODES_WITH_PREFIX (VNx, INT, 8, 2);
 193 VECTOR_MODES_WITH_PREFIX (VNx, FLOAT, 4, 2);
 194 VECTOR_MODES_WITH_PREFIX (VNx, FLOAT, 8, 2);
 195
 196 ADJUST_NUNITS (VNx2QI, aarch64_sve_vg);
 197 ADJUST_NUNITS (VNx2HI, aarch64_sve_vg);
 198 ADJUST_NUNITS (VNx2SI, aarch64_sve_vg);
 199 ADJUST_NUNITS (VNx2HF, aarch64_sve_vg);
 200 ADJUST_NUNITS (VNx2BF, aarch64_sve_vg);
 201 ADJUST_NUNITS (VNx2SF, aarch64_sve_vg);
 202
 203 ADJUST_NUNITS (VNx4QI, aarch64_sve_vg * 2);
 204 ADJUST_NUNITS (VNx4HI, aarch64_sve_vg * 2);
 205 ADJUST_NUNITS (VNx4HF, aarch64_sve_vg * 2);
 206 ADJUST_NUNITS (VNx4BF, aarch64_sve_vg * 2);
 207
 208 ADJUST_NUNITS (VNx8QI, aarch64_sve_vg * 4);
 209
 210 ADJUST_ALIGNMENT (VNx2QI, 1);
 211 ADJUST_ALIGNMENT (VNx4QI, 1);
 212 ADJUST_ALIGNMENT (VNx8QI, 1);
 213
 214 ADJUST_ALIGNMENT (VNx2HI, 2);
 215 ADJUST_ALIGNMENT (VNx4HI, 2);
 216 ADJUST_ALIGNMENT (VNx2HF, 2);
 217 ADJUST_ALIGNMENT (VNx2BF, 2);
 218 ADJUST_ALIGNMENT (VNx4HF, 2);
 219 ADJUST_ALIGNMENT (VNx4BF, 2);
 220
 221 ADJUST_ALIGNMENT (VNx2SI, 4);
 222 ADJUST_ALIGNMENT (VNx2SF, 4);
 223
 224 /* Quad float: 128-bit floating mode for long doubles.  */
 225 FLOAT_MODE (TF, 16, ieee_quad_format);
 226
 227 /* A 4-tuple of SVE vectors with the maximum -msve-vector-bits= setting.
 228    Note that this is a limit only on the compile-time sizes of modes;
 229    it is not a limit on the runtime sizes, since VL-agnostic code
 230    must work with arbitary vector lengths.  */
 231 #define MAX_BITSIZE_MODE_ANY_MODE (2048 * 4)
 232
 233 /* Coefficient 1 is multiplied by the number of 128-bit chunks in an
 234    SVE vector (referred to as "VQ") minus one.  */
 235 #define NUM_POLY_INT_COEFFS 2