rv_major_opcode_1010011.mdwn

   1 # Summary FP Opcodes
   2
   3 This page aids and assists in the development of FP proposals,
   4 by identifying and listing in full both publicly-known proposals
   5 and the full brownfield encoding space available in the 0b010011
   6 major opcode.
   7
   8 Publicly-known FP proposals:
   9
  10 * Zfrsqrt - Reciprocal SQRT <http://bugs.libre-riscv.org/show_bug.cgi?id=110>
  11 * Zftrans - Transcendentals (FSIN, FCOS, FATAN, FPOW, FEXP, FLOG, FRCP)
  12 * HI-half FP MV - <https://github.com/riscv/riscv-isa-manual/pull/301>
  13   <https://groups.google.com/a/groups.riscv.org/forum/m/#!topic/isa-dev/kXgfFqgBv-c>
  14
  15 # Main FP opcode 1010011 table
  16
  17 Proposed new encodings in **bold**
  18
  19 [[!table  data="""
  20 31..27  | 26..25  | 24..20 |19..15| 14...12| 11..7 | 6....0  | function    |
  21 funct5  | SDHQ    | rs2    | rs1  | funct3 | rd    | opcode  | name        |
  22  5      | 2       | 5      | 5    | 3      | 5     |   7     |             |
  23 00000   | xx      | rs2    | rs1  | rm     | rd    | 1010011 | FADD.xx     |
  24 00001   | xx      | rs2    | rs1  | rm     | rd    | 1010011 | FSUB.xx     |
  25 00010   | xx      | rs2    | rs1  | rm     | rd    | 1010011 | FMUL.xx     |
  26 00011   | xx      | rs2    | rs1  | rm     | rd    | 1010011 | FDIV.xx     |
  27 00100   | xx      | rs2    | rs1  | yyy    | rd    | 1010011 | tb=00100    |
  28 00101   | xx      | rs2    | rs1  | yyy    | rd    | 1010011 | tb=00101    |
  29 00110   | xx      | rs2    | rs1  | yyy    | rd    | 1010011 | ?           |
  30 00111   | xx      | rs2    | rs1  | yyy    | rd    | 1010011 | ?           |
  31 01000   | xx      | rs2    | rs1  | yyy    | rd    | 1010011 | tb=01000    |
  32 01001   | xx      | rs2    | rs1  | yyy    | rd    | 1010011 | ?           |
  33 01010   | xx      | rs2    | rs1  | yyy    | rd    | 1010011 | ?           |
  34 01011   | xx      | xxxxx  | rs1  | yyy    | rd    | 1010011 | tb=01011    |
  35 01100   | xx      | rs2    | rs1  | yyy    | rd    | 1010011 | ?           |
  36 01101   | xx      | rs2    | rs1  | yyy    | rd    | 1010011 | ?           |
  37 01110   | xx      | rs2    | rs1  | yyy    | rd    | 1010011 | ?           |
  38 01111   | xx      | rs2    | rs1  | yyy    | rd    | 1010011 | **FPOW.xx** |
  39 10000   | xx      | rs2    | rs1  | yyy    | rd    | 1010011 | ?           |
  40 10001   | xx      | rs2    | rs1  | yyy    | rd    | 1010011 | ?           |
  41 10010   | xx      | rs2    | rs1  | yyy    | rd    | 1010011 | ?           |
  42 10011   | xx      | rs2    | rs1  | yyy    | rd    | 1010011 | ?           |
  43 10100   | xx      | rs2    | rs1  | yyy    | rd    | 1010011 | tb=10100    |
  44 10101   | xx      | rs2    | rs1  | yyy    | rd    | 1010011 | ?           |
  45 10110   | xx      | rs2    | rs1  | yyy    | rd    | 1010011 | ?           |
  46 10111   | xx      | rs2    | rs1  | yyy    | rd    | 1010011 | ?           |
  47 11000   | xx      | xxxxx  | rs1  | yyy    | rd    | 1010011 | tb=11000    |
  48 11001   | xx      | rs2    | rs1  | yyy    | rd    | 1010011 | ?           |
  49 11010   | xx      | xxxxx  | rs1  | yyy    | rd    | 1010011 | tb=11010    |
  50 11100   | xx      | xxxxx  | rs1  | 000    | rd    | 1010011 | tb=11100    |
  51 11101   | xx      | rs2    | rs1  | yyy    | rd    | 1010011 | ?           |
  52 11110   | xx      | xxxxx  | rs1  | 000    | rd    | 1010011 | tb=11110    |
  53 11111   | xx      | rs2    | rs1  | yyy    | rd    | 1010011 | ?           |
  54 """]]
  55
  56 ## funct5 = 00100
  57
  58 [[!table  data="""
  59 31..27  | 26..25  | 24..20 |19..15| 14...12| 11..7 | 6....0  | function    |
  60 funct5  | SDHQ    | rs2    | rs1  | funct3 | rd    | opcode  | name        |
  61  5      | 2       | 5      | 5    | 3      | 5     |   7     |             |
  62 00100   | xx      | rs2    | rs1  | 000    | rd    | 1010011 | FSGNJ.xx    |
  63 00100   | xx      | rs2    | rs1  | 001    | rd    | 1010011 | FSGNJN.xx   |
  64 00100   | xx      | rs2    | rs1  | 010    | rd    | 1010011 | FSGNJX.xx   |
  65 00100   | xx      | rs2    | rs1  | 011    | rd    | 1010011 | ?f3=011     |
  66 00100   | xx      | rs2    | rs1  | 100    | rd    | 1010011 | ?f3=100     |
  67 00100   | xx      | rs2    | rs1  | 101    | rd    | 1010011 | ?f3=101     |
  68 00100   | xx      | rs2    | rs1  | 110    | rd    | 1010011 | ?f3=110     |
  69 00100   | xx      | rs2    | rs1  | 111    | rd    | 1010011 | ?f3=111     |
  70 """]]
  71
  72 # funct5 = 00101
  73
  74 [[!table  data="""
  75 31..27  | 26..25  | 24..20 |19..15| 14...12| 11..7 | 6....0  | function    |
  76 funct5  | SDHQ    | rs2    | rs1  | funct3 | rd    | opcode  | name        |
  77  5      | 2       | 5      | 5    | 3      | 5     |   7     |             |
  78 00101   | xx      | rs2    | rs1  | 000    | rd    | 1010011 | FMIN.S      |
  79 00101   | xx      | rs2    | rs1  | 001    | rd    | 1010011 | FMAX.S      |
  80 00101   | xx      | rs2    | rs1  | 010    | rd    | 1010011 | ?f3=010     |
  81 00101   | xx      | rs2    | rs1  | 011    | rd    | 1010011 | ?f3=011     |
  82 00101   | xx      | rs2    | rs1  | 100    | rd    | 1010011 | ?f3=100     |
  83 00101   | xx      | rs2    | rs1  | 101    | rd    | 1010011 | ?f3=101     |
  84 00101   | xx      | rs2    | rs1  | 110    | rd    | 1010011 | ?f3=110     |
  85 00101   | xx      | rs2    | rs1  | 111    | rd    | 1010011 | ?f3=111     |
  86 """]]
  87
  88 # funct5 = 01000
  89
  90 Notes:
  91
  92 * TODO FP16 (trivial)
  93
  94 [[!table  data="""
  95 31..27  | 26..25  | 24..20 |19..15| 14...12| 11..7 | 6....0  | function    |
  96 funct5  | SDHQ    | rs2    | rs1  | funct3 | rd    | opcode  | name        |
  97  5      | 2       | 5      | 5    | 3      | 5     |   7     |             |
  98 01000   | 00      | 00001  | rs1  | rm     | rd    | 1010011 | FCVT.S.D    |
  99 01000   | 00      | 00011  | rs1  | rm     | rd    | 1010011 | FCVT.S.Q    |
 100 01000   | 00      | xxxxx  | rs1  | rm     | rd    | 1010011 | rs2?        |
 101 ------  | -----   | -----  | -----| -----  | ----- | ------- | --------    |
 102 01000   | 01      | 00000  | rs1  | rm     | rd    | 1010011 | FCVT.D.S    |
 103 01000   | 01      | 00011  | rs1  | rm     | rd    | 1010011 | FCVT.D.Q    |
 104 01000   | 01      | xxxxx  | rs1  | rm     | rd    | 1010011 | rs2?        |
 105 ------  | -----   | -----  | -----| -----  | ----- | ------- | --------    |
 106 01000   | 11      | 00000  | rs1  | rm     | rd    | 1010011 | FCVT.Q.S    |
 107 01000   | 11      | 00001  | rs1  | rm     | rd    | 1010011 | FCVT.Q.D    |
 108 01000   | 11      | xxxxx  | rs1  | rm     | rd    | 1010011 | rs2?        |
 109 """]]
 110
 111 # funct5 = 01011
 112
 113 [[!table  data="""
 114 31..27  | 26..25  | 24..20 |19..15| 14...12| 11..7 | 6....0  | function      |
 115 funct5  | SDHQ    | rs2    | rs1  | funct3 | rd    | opcode  | name          |
 116  5      | 2       | 5      | 5    | 3      | 5     |   7     |               |
 117 01011   | xx      | 00000  | rs1  | yyy    | rd    | 1010011 | FSQRT.xx      |
 118 01011   | xx      | 00001  | rs1  | yyy    | rd    | 1010011 | **FRSQRT.xx** |
 119 01011   | xx      | 00010  | rs1  | yyy    | rd    | 1010011 | **FSIN.xx**   |
 120 01011   | xx      | 00011  | rs1  | yyy    | rd    | 1010011 | **FCOS.xx**   |
 121 01011   | xx      | 00100  | rs1  | yyy    | rd    | 1010011 | **FATAN.xx**  |
 122 01011   | xx      | 00101  | rs1  | yyy    | rd    | 1010011 | **FEXP.xx**   |
 123 01011   | xx      | 00110  | rs1  | yyy    | rd    | 1010011 | **FLOG.xx**   |
 124 01011   | xx      | 00111  | rs1  | yyy    | rd    | 1010011 | **FRCP.xx**   |
 125 01011   | xx      | 01000  | rs1  | yyy    | rd    | 1010011 | ?             |
 126 01011   | xx      | 01001  | rs1  | yyy    | rd    | 1010011 | ?             |
 127 01011   | xx      | 01010  | rs1  | yyy    | rd    | 1010011 | ?             |
 128 01011   | xx      | 01011  | rs1  | yyy    | rd    | 1010011 | ?             |
 129 01011   | xx      | 01100  | rs1  | yyy    | rd    | 1010011 | ?             |
 130 01011   | xx      | 01101  | rs1  | yyy    | rd    | 1010011 | ?             |
 131 01011   | xx      | 01110  | rs1  | yyy    | rd    | 1010011 | ?             |
 132 01011   | xx      | 01111  | rs1  | yyy    | rd    | 1010011 | ?             |
 133 01011   | xx      | 10000  | rs1  | yyy    | rd    | 1010011 | ?             |
 134 01011   | xx      | 10001  | rs1  | yyy    | rd    | 1010011 | ?             |
 135 01011   | xx      | 10010  | rs1  | yyy    | rd    | 1010011 | ?             |
 136 01011   | xx      | 10011  | rs1  | yyy    | rd    | 1010011 | ?             |
 137 01011   | xx      | 10100  | rs1  | yyy    | rd    | 1010011 | ?             |
 138 01011   | xx      | 10101  | rs1  | yyy    | rd    | 1010011 | ?             |
 139 01011   | xx      | 10110  | rs1  | yyy    | rd    | 1010011 | ?             |
 140 01011   | xx      | 10111  | rs1  | yyy    | rd    | 1010011 | ?             |
 141 01011   | xx      | 11000  | rs1  | yyy    | rd    | 1010011 | ?             |
 142 01011   | xx      | 11001  | rs1  | yyy    | rd    | 1010011 | ?             |
 143 01011   | xx      | 11010  | rs1  | yyy    | rd    | 1010011 | ?             |
 144 01011   | xx      | 11011  | rs1  | yyy    | rd    | 1010011 | ?             |
 145 01011   | xx      | 11100  | rs1  | yyy    | rd    | 1010011 | ?             |
 146 01011   | xx      | 11101  | rs1  | yyy    | rd    | 1010011 | ?             |
 147 01011   | xx      | 11110  | rs1  | yyy    | rd    | 1010011 | ?             |
 148 01011   | xx      | 11111  | rs1  | yyy    | rd    | 1010011 | ?             |
 149 """]]
 150
 151 # funct5 = 10100
 152
 153 Notes:
 154
 155 * FNE missing?
 156
 157 [[!table  data="""
 158 31..27  | 26..25  | 24..20 |19..15| 14...12| 11..7 | 6....0  | function    |
 159 funct5  | SDHQ    | rs2    | rs1  | funct3 | rd    | opcode  | name        |
 160  5      | 2       | 5      | 5    | 3      | 5     |   7     |             |
 161 10100   | xx      | rs2    | rs1  | 000    | rd    | 1010011 | FLE.xx      |
 162 10100   | xx      | rs2    | rs1  | 001    | rd    | 1010011 | FLT.xx      |
 163 10100   | xx      | rs2    | rs1  | 010    | rd    | 1010011 | FEQ.xx      |
 164 10100   | xx      | rs2    | rs1  | 011    | rd    | 1010011 | ?f3=011     |
 165 10100   | xx      | rs2    | rs1  | 100    | rd    | 1010011 | ?f3=100     |
 166 10100   | xx      | rs2    | rs1  | 101    | rd    | 1010011 | ?f3=101     |
 167 10100   | xx      | rs2    | rs1  | 110    | rd    | 1010011 | ?f3=110     |
 168 10100   | xx      | rs2    | rs1  | 111    | rd    | 1010011 | ?f3=111     |
 169 """]]
 170
 171 # funct5 = 11000
 172
 173 Notes:
 174
 175 * TODO FP16 (trivial)
 176
 177 [[!table  data="""
 178 31..27  | 26..25  | 24..20 |19..15| 14...12| 11..7 | 6....0  | function    |
 179 funct5  | SDHQ    | rs2    | rs1  | funct3 | rd    | opcode  | name        |
 180  5      | 2       | 5      | 5    | 3      | 5     |   7     |             |
 181 11000   | 00      | 00000  | rs1  | rm     | rd    | 1010011 | FCVT.W.S    |
 182 11000   | 00      | 00001  | rs1  | rm     | rd    | 1010011 | FCVT.WU.S   |
 183 11000   | 00      | 00010  | rs1  | rm     | rd    | 1010011 | FCVT.L.S    |
 184 11000   | 00      | 00011  | rs1  | rm     | rd    | 1010011 | FCVT.LU.S   |
 185 11000   | 00      | xxxxx  | rs1  | rm     | rd    | 1010011 | rs2?        |
 186 ------  | -----   | -----  | -----| -----  | ----- | ------- | --------    |
 187 11000   | 01      | 00000  | rs1  | rm     | rd    | 1010011 | FCVT.W.D    |
 188 11000   | 01      | 00001  | rs1  | rm     | rd    | 1010011 | FCVT.WU.D   |
 189 11000   | 01      | 00010  | rs1  | rm     | rd    | 1010011 | FCVT.L.D    |
 190 11000   | 01      | 00011  | rs1  | rm     | rd    | 1010011 | FCVT.LU.D   |
 191 11000   | 01      | xxxxx  | rs1  | rm     | rd    | 1010011 | rs2?        |
 192 ------  | -----   | -----  | -----| -----  | ----- | ------- | --------    |
 193 11000   | 11      | 00000  | rs1  | rm     | rd    | 1010011 | FCVT.W.Q    |
 194 11000   | 11      | 00001  | rs1  | rm     | rd    | 1010011 | FCVT.WU.Q   |
 195 11000   | 11      | 00010  | rs1  | rm     | rd    | 1010011 | FCVT.L.Q    |
 196 11000   | 11      | 00011  | rs1  | rm     | rd    | 1010011 | FCVT.LU.Q   |
 197 11000   | 11      | xxxxx  | rs1  | rm     | rd    | 1010011 | rs2?        |
 198 """]]
 199
 200 # funct5 = 11010
 201
 202 [[!table  data="""
 203 31..27  | 26..25  | 24..20 |19..15| 14...12| 11..7 | 6....0  | function    |
 204 funct5  | SDHQ    | rs2    | rs1  | funct3 | rd    | opcode  | name        |
 205  5      | 2       | 5      | 5    | 3      | 5     |   7     |             |
 206 11010   | 00      | 00000  | rs1  | rm     | rd    | 1010011 | FCVT.S.W    |
 207 11010   | 00      | 00001  | rs1  | rm     | rd    | 1010011 | FCVT.S.WU   |
 208 11010   | 00      | 00010  | rs1  | rm     | rd    | 1010011 | FCVT.S.L    |
 209 11010   | 00      | 00011  | rs1  | rm     | rd    | 1010011 | FCVT.S.LU   |
 210 11010   | 00      | xxxxx  | rs1  | rm     | rd    | 1010011 | rs2?        |
 211 ------  | -----   | -----  | -----| -----  | ----- | ------- | --------    |
 212 11010   | 01      | 00000  | rs1  | rm     | rd    | 1010011 | FCVT.D.W    |
 213 11010   | 01      | 00001  | rs1  | rm     | rd    | 1010011 | FCVT.D.WU   |
 214 11010   | 01      | 00010  | rs1  | rm     | rd    | 1010011 | FCVT.D.L    |
 215 11010   | 01      | 00011  | rs1  | rm     | rd    | 1010011 | FCVT.D.LU   |
 216 11010   | 01      | xxxxx  | rs1  | rm     | rd    | 1010011 | rs2?        |
 217 ------  | -----   | -----  | -----| -----  | ----- | ------- | --------    |
 218 11010   | 11      | 00000  | rs1  | rm     | rd    | 1010011 | FCVT.Q.W    |
 219 11010   | 11      | 00001  | rs1  | rm     | rd    | 1010011 | FCVT.Q.WU   |
 220 11010   | 11      | 00010  | rs1  | rm     | rd    | 1010011 | FCVT.Q.L    |
 221 11010   | 11      | 00011  | rs1  | rm     | rd    | 1010011 | FCVT.Q.LU   |
 222 11010   | 11      | xxxxx  | rs1  | rm     | rd    | 1010011 | rs2?        |
 223 """]]
 224
 225 # funct5 = 11100
 226
 227 Notes:
 228
 229 * FMV.X.Q is missing (alias of FMVH.X.D if it existed)
 230 * TODO FP16 (trivial)
 231 * FMVH.X.HW (half-word) missing?
 232
 233 [[!table  data="""
 234 31..27| 26..25| 24..20 |19..15|14...12| 11..7 | 6....0  | function    |
 235 funct5| SDHQ  | rs2    | rs1  |funct3 | rd    | opcode  | name        |
 236  5    | 2     | 5      | 5    | 3     | 5     |   7     |             |
 237 11100 | 00    | 00000  | rs1  | 000   | rd    | 1010011 | FMV.X.W     |
 238 11100 | 00    | 00000  | rs1  | 001   | rd    | 1010011 | FCLASS.S    |
 239 11100 | 00    | xxxxx  | rs1  | yyy   | rd    | 1010011 | rs2? f3?    |
 240 ------| ----- | -----  | -----| ----- | ----- | ------- | --------    |
 241 11100 | 01    | 00000  | rs1  | 000   | rd    | 1010011 | FMV.X.D **FMVH.X.W** |
 242 11100 | 01    | 00000  | rs1  | 001   | rd    | 1010011 | FCLASS.D    |
 243 11100 | xx    | xxxxx  | rs1  | yyy   | rd    | 1010011 | rs2? f3?    |
 244 ------| ----- | -----  | -----| ----- | ----- | ------- | --------    |
 245 11100 | 11    | 00000  | rs1  | 000   | rd    | 1010011 | **FMVH.X.D** |
 246 11100 | 11    | 00000  | rs1  | 001   | rd    | 1010011 | FCLASS.Q    |
 247 11100 | xx    | xxxxx  | rs1  | yyy   | rd    | 1010011 | rs2? f3?    |
 248 """]]
 249
 250 # funct5 = 11110
 251
 252 Notes:
 253
 254 * FMV.Q.X is missing (as is FMVH.D.X)
 255 * FMVH.W.X is missing (alias of FMV.D.X)
 256 * TODO FP16 (trivial)
 257 * FMVH.HW.X (half-word) missing?
 258
 259 [[!table  data="""
 260 31..27  | 26..25  | 24..20 |19..15| 14...12| 11..7 | 6....0  | function    |
 261 funct5  | SDHQ    | rs2    | rs1  | funct3 | rd    | opcode  | name        |
 262  5      | 2       | 5      | 5    | 3      | 5     |   7     |             |
 263 11110   | 00      | 00000  | rs1  | 000    | rd    | 1010011 | FMV.W.X     |
 264 11110   | 00      | xxxxx  | rs1  | yyy    | rd    | 1010011 | rs2? f3?    |
 265 ------  | -----   | -----  | -----| -----  | ----- | ------- | --------    |
 266 11110   | 01      | 00000  | rs1  | 000    | rd    | 1010011 | FMV.D.X     |
 267 11110   | 01      | xxxxx  | rs1  | yyy    | rd    | 1010011 | rs2? f3?    |
 268 ------  | -----   | -----  | -----| -----  | ----- | ------- | --------    |
 269 11110   | 11      | 00000  | rs1  | 000    | rd    | 1010011 | ?           |
 270 11110   | 11      | xxxxx  | rs1  | yyy    | rd    | 1010011 | rs2? f3?    |
 271 """]]
 272
 273 # funct5 = ?????
 274
 275 [[!table  data="""
 276 31..27  | 26..25  | 24..20 |19..15| 14...12| 11..7 | 6....0  | function    |
 277 funct5  | SDHQ    | rs2    | rs1  | funct3 | rd    | opcode  | name        |
 278  5      | 2       | 5      | 5    | 3      | 5     |   7     |             |
 279 ------  | -----   | -----  | -----| -----  | ----- | ------- | --------    |
 280 """]]
 281