wiki:GcnInstrsVop1

Version 22 (modified by trac, 8 years ago) (diff)

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GCN ISA VOP1/VOP3 instructions

VOP1 instructions can be encoded in the VOP1 encoding and the VOP3A/VOP3B encoding. List of fields for VOP1 encoding:

Bits Name Description
0-8 SRC0 First (scalar or vector) source operand
9-16 OPCODE Operation code
17-24 VDST Destination vector operand
25-31 ENCODING Encoding type. Must be 0b0111111

Syntax: INSTRUCTION VDST, SRC0

List of fields for VOP3A/VOP3B encoding (GCN 1.0/1.1):

Bits Name Description
0-7 VDST Vector destination operand
8-10 ABS Absolute modifiers for source operands (VOP3A)
8-14 SDST Scalar destination operand (VOP3B)
11 CLAMP CLAMP modifier (VOP3A)
15 CLAMP CLAMP modifier (VOP3B)
17-25 OPCODE Operation code
26-31 ENCODING Encoding type. Must be 0b110100
32-40 SRC0 First (scalar or vector) source operand
41-49 SRC1 Second (scalar or vector) source operand
50-58 SRC2 Third (scalar or vector) source operand
59-60 OMOD OMOD modifier. Multiplication modifier
61-63 NEG Negation modifier for source operands

List of fields for VOP3A/VOP3B encoding (GCN 1.2):

Bits Name Description
0-7 VDST Destination vector operand
8-10 ABS Absolute modifiers for source operands (VOP3A)
8-14 SDST Scalar destination operand (VOP3B)
15 CLAMP CLAMP modifier
16-25 OPCODE Operation code
26-31 ENCODING Encoding type. Must be 0b110100
32-40 SRC0 First (scalar or vector) source operand
41-49 SRC1 Second (scalar or vector) source operand
50-58 SRC2 Third (scalar or vector) source operand
59-60 OMOD OMOD modifier. Multiplication modifier
61-63 NEG Negation modifier for source operands

Syntax: INSTRUCTION VDST, SRC0 [MODIFIERS]

Modifiers:

  • CLAMP - clamps destination floating point value in range 0.0-1.0
  • MUL:2, MUL:4, DIV:2 - OMOD modifiers. Multiply destination floating point value by 2.0, 4.0 or 0.5 respectively. Clamping applied after OMOD modifier.
  • -SRC - negate floating point value from source operand. Applied after ABS modifier.
  • ABS(SRC) - apply absolute value to source operand

NOTE: OMOD modifier doesn't work if output denormals are allowed (5 bit of MODE register for single precision or 7 bit for double precision).
NOTE: OMOD and CLAMP modifier affects only for instruction that output is floating point value.
NOTE: ABS and negation is applied to source operand for any instruction.

Negation and absolute value can be combined: -ABS(V0). Modifiers CLAMP and OMOD (MUL:2, MUL:4 and DIV:2) can be given in random order.

Limitations for operands:

  • only one SGPR can be read by instruction. Multiple occurrences of this same SGPR is allowed
  • only one literal constant can be used, and only when a SGPR or M0 is not used in source operands
  • only SRC0 can holds LDS_DIRECT

Unaligned pairs of SGPRs are allowed in source operands.

VOP1 opcodes (0-127) are reflected in VOP3 in range: 384-511 for GCN 1.0/1.1 or 320-447 for GCN 1.2.

List of the instructions by opcode (GCN 1.0/1.1):

Opcode Opcode(VOP3) GCN 1.0 GCN 1.1 Mnemonic
0 (0x0) 384 (0x180) V_NOP
1 (0x1) 385 (0x181) V_MOV_B32
2 (0x2) 386 (0x182) V_READFIRSTLANE_B32
3 (0x3) 387 (0x183) V_CVT_I32_F64
4 (0x4) 388 (0x184) V_CVT_F64_I32
5 (0x5) 389 (0x185) V_CVT_F32_I32
6 (0x6) 390 (0x186) V_CVT_F32_U32
7 (0x7) 391 (0x187) V_CVT_U32_F32
8 (0x8) 392 (0x188) V_CVT_I32_F32
9 (0x9) 393 (0x189) V_MOV_FED_B32
10 (0xa) 394 (0x18a) V_CVT_F16_F32
11 (0xb) 395 (0x18b) V_CVT_F32_F16
12 (0xc) 396 (0x18c) V_CVT_RPI_I32_F32
13 (0xd) 397 (0x18d) V_CVT_FLR_I32_F32
14 (0xe) 398 (0x18e) V_CVT_OFF_F32_I4
15 (0xf) 399 (0x18f) V_CVT_F32_F64
16 (0x10) 400 (0x190) V_CVT_F64_F32
17 (0x11) 401 (0x191) V_CVT_F32_UBYTE0
18 (0x12) 402 (0x192) V_CVT_F32_UBYTE1
19 (0x13) 403 (0x193) V_CVT_F32_UBYTE2
20 (0x14) 404 (0x194) V_CVT_F32_UBYTE3
21 (0x15) 405 (0x195) V_CVT_U32_F64
22 (0x16) 406 (0x196) V_CVT_F64_U32
23 (0x17) 407 (0x197) V_TRUNC_F64
24 (0x18) 408 (0x198) V_CEIL_F64
25 (0x19) 409 (0x199) V_RNDNE_F64
26 (0x1a) 410 (0x19a) V_FLOOR_F64
32 (0x20) 416 (0x1a0) V_FRACT_F32
33 (0x21) 417 (0x1a1) V_TRUNC_F32
34 (0x22) 418 (0x1a2) V_CEIL_F32
35 (0x23) 419 (0x1a3) V_RNDNE_F32
36 (0x24) 420 (0x1a4) V_FLOOR_F32
37 (0x25) 421 (0x1a5) V_EXP_F32
38 (0x26) 422 (0x1a6) V_LOG_CLAMP_F32
39 (0x27) 423 (0x1a7) V_LOG_F32
40 (0x28) 424 (0x1a8) V_RCP_CLAMP_F32
41 (0x29) 425 (0x1a9) V_RCP_LEGACY_F32
42 (0x2a) 426 (0x1aa) V_RCP_F32
43 (0x2b) 427 (0x1ab) V_RCP_IFLAG_F32
44 (0x2c) 428 (0x1ac) V_RSQ_CLAMP_F32
45 (0x2d) 429 (0x1ad) V_RSQ_LEGACY_F32
46 (0x2e) 430 (0x1ae) V_RSQ_F32
47 (0x2f) 431 (0x1af) V_RCP_F64
48 (0x30) 432 (0x1b0) V_RCP_CLAMP_F64
49 (0x31) 433 (0x1b1) V_RSQ_F64
50 (0x32) 434 (0x1b2) V_RSQ_CLAMP_F64
51 (0x33) 435 (0x1b3) V_SQRT_F32
52 (0x34) 436 (0x1b4) V_SQRT_F64
53 (0x35) 437 (0x1b5) V_SIN_F32
54 (0x36) 438 (0x1b6) V_COS_F32
55 (0x37) 439 (0x1b7) V_NOT_B32
56 (0x38) 440 (0x1b8) V_BFREV_B32
57 (0x39) 441 (0x1b9) V_FFBH_U32
58 (0x3a) 442 (0x1ba) V_FFBL_B32
59 (0x3b) 443 (0x1bb) V_FFBH_I32
60 (0x3c) 444 (0x1bc) V_FREXP_EXP_I32_F64
61 (0x3d) 445 (0x1bd) V_FREXP_MANT_F64
62 (0x3e) 446 (0x1be) V_FRACT_F64
63 (0x3f) 447 (0x1bf) V_FREXP_EXP_I32_F32
64 (0x40) 448 (0x1c0) V_FREXP_MANT_F32
65 (0x41) 449 (0x1c1) V_CLREXCP
66 (0x42) 450 (0x1c2) V_MOVRELD_B32
67 (0x43) 451 (0x1c3) V_MOVRELS_B32
68 (0x44) 452 (0x1c4) V_MOVRELSD_B32
69 (0x45) 453 (0x1c5) V_LOG_LEGACY_F32
70 (0x46) 454 (0x1c6) V_EXP_LEGACY_F32

List of the instructions by opcode (GCN 1.2):

Opcode Opcode(VOP3) Mnemonic
0 (0x0) 320 (0x140) V_NOP
1 (0x1) 321 (0x141) V_MOV_B32
2 (0x2) 322 (0x142) V_READFIRSTLANE_B32
3 (0x3) 323 (0x143) V_CVT_I32_F64
4 (0x4) 324 (0x144) V_CVT_F64_I32
5 (0x5) 325 (0x145) V_CVT_F32_I32
6 (0x6) 326 (0x146) V_CVT_F32_U32
7 (0x7) 327 (0x147) V_CVT_U32_F32
8 (0x8) 328 (0x148) V_CVT_I32_F32
9 (0x9) 329 (0x149) V_MOV_FED_B32
10 (0xa) 330 (0x14a) V_CVT_F16_F32
11 (0xb) 331 (0x14b) V_CVT_F32_F16
12 (0xc) 332 (0x14c) V_CVT_RPI_I32_F32
13 (0xd) 333 (0x14d) V_CVT_FLR_I32_F32
14 (0xe) 334 (0x14e) V_CVT_OFF_F32_I4
15 (0xf) 335 (0x14f) V_CVT_F32_F64
16 (0x10) 336 (0x150) V_CVT_F64_F32
17 (0x11) 337 (0x151) V_CVT_F32_UBYTE0
18 (0x12) 338 (0x152) V_CVT_F32_UBYTE1
19 (0x13) 339 (0x153) V_CVT_F32_UBYTE2
20 (0x14) 340 (0x154) V_CVT_F32_UBYTE3
21 (0x15) 341 (0x155) V_CVT_U32_F64
22 (0x16) 342 (0x156) V_CVT_F64_U32
23 (0x17) 343 (0x157) V_TRUNC_F64
24 (0x18) 344 (0x158) V_CEIL_F64
25 (0x19) 345 (0x159) V_RNDNE_F64
26 (0x1a) 346 (0x15a) V_FLOOR_F64
27 (0x1b) 347 (0x15b) V_FRACT_F32
28 (0x1c) 348 (0x15c) V_TRUNC_F32
29 (0x1d) 349 (0x15d) V_CEIL_F32
30 (0x1e) 350 (0x15e) V_RNDNE_F32
31 (0x1f) 351 (0x15f) V_FLOOR_F32
32 (0x20) 352 (0x160) V_EXP_F32
33 (0x21) 353 (0x161) V_LOG_F32
34 (0x22) 354 (0x162) V_RCP_F32
35 (0x23) 355 (0x163) V_RCP_IFLAG_F32
36 (0x24) 356 (0x164) V_RSQ_F32
37 (0x25) 357 (0x165) V_RCP_F64
38 (0x26) 358 (0x166) V_RSQ_F64
39 (0x27) 359 (0x167) V_SQRT_F32
40 (0x28) 360 (0x168) V_SQRT_F64
41 (0x29) 361 (0x169) V_SIN_F32
42 (0x2a) 362 (0x16a) V_COS_F32
43 (0x2b) 363 (0x16b) V_NOT_B32
44 (0x2c) 364 (0x16c) V_BFREV_B32
45 (0x2d) 365 (0x16d) V_FFBH_U32
46 (0x2e) 366 (0x16e) V_FFBL_B32
47 (0x2f) 367 (0x16f) V_FFBH_I32
48 (0x30) 368 (0x170) V_FREXP_EXP_I32_F64
49 (0x31) 369 (0x171) V_FREXP_MANT_F64
50 (0x32) 370 (0x172) V_FRACT_F64
51 (0x33) 371 (0x173) V_FREXP_EXP_I32_F32
52 (0x34) 372 (0x174) V_FREXP_MANT_F32
53 (0x35) 373 (0x175) V_CLREXCP
54 (0x36) 374 (0x176) V_MOVRELD_B32
55 (0x37) 375 (0x177) V_MOVRELS_B32
56 (0x38) 376 (0x178) V_MOVRELSD_B32
57 (0x39) 377 (0x179) V_CVT_F16_U16
58 (0x3a) 378 (0x17a) V_CVT_F16_I16
59 (0x3b) 379 (0x17b) V_CVT_U16_F16
60 (0x3c) 380 (0x17c) V_CVT_I16_F16
61 (0x3d) 381 (0x17d) V_RCP_F16
62 (0x3e) 382 (0x17e) V_SQRT_F16
63 (0x3f) 383 (0x17f) V_RSQ_F16
64 (0x40) 384 (0x180) V_LOG_F16
65 (0x41) 385 (0x181) V_EXP_F16
66 (0x42) 386 (0x182) V_FREXP_MANT_F16
67 (0x43) 387 (0x183) V_FREXP_EXP_I16_F16
68 (0x44) 388 (0x184) V_FLOOR_F16
69 (0x45) 389 (0x185) V_CEIL_F16
70 (0x46) 390 (0x186) V_TRUNC_F16
71 (0x47) 391 (0x187) V_RNDNE_F16
72 (0x48) 392 (0x188) V_FRACT_F16
73 (0x49) 393 (0x189) V_SIN_F16
74 (0x4a) 394 (0x18a) V_COS_F16
75 (0x4b) 395 (0x18b) V_EXP_LEGACY_F32
76 (0x4c) 396 (0x18c) V_LOG_LEGACY_F32

Instruction set

Alphabetically sorted instruction list:

V_BFREV_B32

Opcode VOP1: 56 (0x38) for GCN 1.0/1.1; 44 (0x2c) for GCN 1.2
Opcode VOP3A: 440 (0x1b8) for GCN 1.0/1.1; 364 (0x16c) for GCN 1.2
Syntax: V_BFREV_B32 VDST, SRC0
Reverse bits in SRC0 and store result to VDST.
Operation:
VDST = REVBIT(SRC0)

V_CEIL_F32

Opcode VOP1: 34 (0x22) for GCN 1.0/1.1; 29 (0x1d) for GCN 1.2
Opcode VOP3A: 418 (0x1a2) for GCN 1.0/1.1; 349 (0x15d) for GCN 1.2
Syntax: V_CEIL_F32 VDST, SRC0
Description: Truncate floating point valu from SRC0 with rounding to positive infinity (ceilling), and store result to VDST. Implemented by flooring. If SRC0 is infinity or NaN then copy SRC0 to VDST.
Operation:
FLOAT F = FLOOR(ASFLOAT(SRC0)) if (ASFLOAT(SRC0) > 0.0 && ASFLOAT(SRC0) != F) F += 1.0 VDST = F

V_CEIL_F64

Opcode VOP1: 24 (0x18) for GCN 1.1/1.2
Opcode VOP3A: 408 (0x198) for GCN 1.1; 344 (0x158) for GCN 1.2
Syntax: V_CEIL_F64 VDST(2), SRC0(2)
Description: Truncate double floating point valu from SRC0 with rounding to positive infinity (ceilling), and store result to VDST. Implemented by flooring. If SRC0 is infinity or NaN then copy SRC0 to VDST.
Operation:
DOUBLE F = FLOOR(ASDOUBLE(SRC0)) if (ASDOUBLE(SRC0) > 0.0 && ASDOUBLE(SRC0) != F) F += 1.0 VDST = F

V_CLREXCP

Opcode VOP1: 65 (0x41) for GCN 1.0/1.1; 53 (0x35) for GCN 1.2
Opcode VOP3A: 449 (0x1c1) for GCN 1.0/1.1; 373 (0x175) for GCN 1.2
Syntax: V_CLREXCP
Description: Clear wave's exception state in SIMD.

V_COS_F32

Opcode VOP1: 54 (0x36) for GCN 1.0/1.1; 42 (0x2a) for GCN 1.2
Opcode VOP3A: 438 (0x1b6) for GCN 1.0/1.1; 362 (0x16a) for GCN 1.2
Syntax: V_COS_F32 VDST, SRC0
Description: Compute cosine of FP value from SRC0. Input value must be normalized to range 1.0 - 1.0 (-360 degree : 360 degree). If SRC0 value is out of range then store 1.0 to VDST. If SRC0 value is infinity, store -NAN to VDST.
Operation:
FLOAT SF = ASFLOAT(SRC0) VDST = 1.0 if (SF >= -1.0 && SF <= 1.0) VDST = APPROX_COS(SF) else if (ABS(SF)==INF) VDST = -NAN else if (ISNAN(SF)) VDST = SRC0

V_CVT_F16_F32

Opcode VOP1: 10 (0xa)
Opcode VOP3A: 394 (0x18a) for GCN 1.0/1.1; 330 (0x14a) for GCN 1.2
Syntax: V_CVT_F16_F32 VDST, SRC0
Description: Convert single FP value to half floating point value with rounding from MODE register (single FP rounding mode), and store result to VDST. If absolute value is too high, then store -/+infinity to VDST.
Operation:
VDST = CVTHALF(ASFLOAT(SRC0))

V_CVT_F32_F16

Opcode VOP1: 11 (0xb)
Opcode VOP3A: 395 (0x18b) for GCN 1.0/1.1; 331 (0x14b) for GCN 1.2
Syntax: V_CVT_F32_F16 VDST, SRC0
Description: Convert half FP value to single FP value, and store result to VDST.
Operation:
VDST = (FLOAT)(ASHALF(SRC0))

V_CVT_F32_F64

Opcode VOP1: 15 (0xf)
Opcode VOP3A: 399 (0x18f) for GCN 1.0/1.1; 335 (0x14f) for GCN 1.2
Syntax: V_CVT_F32_F64 VDST, SRC0(2)
Description: Convert double FP value to single floating point value with rounding from MODE register (single FP rounding mode), and store result to VDST. If absolute value is too high, then store -/+infinity to VDST.
Operation:
VDST = CVTHALF(ASDOUBLE(SRC0))

V_CVT_F32_I32

Opcode VOP1: 5 (0x5)
Opcode VOP3A: 389 (0x185) for GCN 1.0/1.1; 325 (0x145) for GCN 1.2
Syntax: V_CVT_F32_I32 VDST, SRC0
Description: Convert signed 32-bit integer to single FP value, and store it to VDST.
Operation:
VDST = (FLOAT)(INT32)SRC0

V_CVT_F32_U32

Opcode VOP1: 6 (0x6)
Opcode VOP3A: 390 (0x186) for GCN 1.0/1.1; 326 (0x146) for GCN 1.2
Syntax: V_CVT_F32_U32 VDST, SRC0
Description: Convert unsigned 32-bit integer to single FP value, and store it to VDST.
Operation:
VDST = (FLOAT)SRC0

V_CVT_F32_UBYTE0

Opcode VOP1: 17 (0x11)
Opcode VOP3A: 401 (0x191) for GCN 1.0/1.1; 337 (0x151) for GCN 1.2
Syntax: V_CVT_F32_UBYTE0 VDST, SRC0
Description: Convert the first unsigned 8-bit byte from SRC0 to single FP value, and store it to VDST.
Operation:
VDST = (FLOAT)(SRC0 & 0xff)

V_CVT_F32_UBYTE1

Opcode VOP1: 18 (0x12)
Opcode VOP3A: 402 (0x192) for GCN 1.0/1.1; 338 (0x152) for GCN 1.2
Syntax: V_CVT_F32_UBYTE1 VDST, SRC0
Description: Convert the second unsigned 8-bit byte from SRC0 to single FP value, and store it to VDST.
Operation:
VDST = (FLOAT)((SRC0>>8) & 0xff)

V_CVT_F32_UBYTE2

Opcode VOP1: 19 (0x13)
Opcode VOP3A: 403 (0x193) for GCN 1.0/1.1; 339 (0x153) for GCN 1.2
Syntax: V_CVT_F32_UBYTE2 VDST, SRC0
Description: Convert the third unsigned 8-bit byte from SRC0 to single FP value, and store it to VDST.
Operation:
VDST = (FLOAT)((SRC0>>16) & 0xff)

V_CVT_F32_UBYTE3

Opcode VOP1: 20 (0x14)
Opcode VOP3A: 404 (0x194) for GCN 1.0/1.1; 340 (0x154) for GCN 1.2
Syntax: V_CVT_F32_UBYTE3 VDST, SRC0
Description: Convert the fourth unsigned 8-bit byte from SRC0 to single FP value, and store it to VDST.
Operation:
VDST = (FLOAT)(SRC0>>24)

V_CVT_F64_F32

Opcode VOP1: 16 (0x10)
Opcode VOP3A: 400 (0x190) for GCN 1.0/1.1; 336 (0x150) for GCN 1.2
Syntax: V_CVT_F64_F32 VDST(2), SRC0
Description: Convert single FP value to double FP value, and store result to VDST.
Operation:
VDST = (DOUBLE)(ASFLOAT(SRC0))

V_CVT_F64_I32

Opcode VOP1: 4 (0x4)
Opcode VOP3A: 388 (0x184) for GCN 1.0/1.1; 324 (0x144) for GCN 1.2
Syntax: V_CVT_F64_I32 VDST(2), SRC0
Description: Convert signed 32-bit integer to double FP value, and store it to VDST.
Operation:
VDST = (DOUBLE)(INT32)SRC0

V_CVT_F64_U32

Opcode VOP1: 22 (0x16)
Opcode VOP3A: 406 (0x196) for GCN 1.0/1.1; 342 (0x156) for GCN 1.2
Syntax: V_CVT_F64_U32 VDST(2), SRC0
Description: Convert unsigned 32-bit integer to double FP value, and store it to VDST.
Operation:
VDST = (DOUBLE)SRC0

V_CVT_FLR_I32_F32

Opcode VOP1: 13 (0xd)
Opcode VOP3A: 397 (0x18d) for GCN 1.0/1.1; 333 (0x14d) for GCN 1.2
Syntax: V_CVT_FLR_I32_F32 VDST, SRC0
Description: Convert 32-bit floating point value from SRC0 to signed 32-bit integer, and store result to VDST. Conversion uses rounding to negative infinity (floor). If value is higher/lower than maximal/minimal integer then store MAX_INT32/MIN_INT32 to VDST. If input value is NaN/-NaN then store MAX_INT32/MIN_INT32 to VDST.
Operation:
FLOAT SF = ASFLOAT(SF) if (!ISNAN(SF)) VDST = (INT32)MAX(MIN(FLOOR(SF), 2147483647.0), -2147483648.0) else VDST = (INT32)SF>=0 ? 2147483647 : -2147483648

V_CVT_I32_F32

Opcode VOP1: 8 (0x8)
Opcode VOP3A: 392 (0x188) for GCN 1.0/1.1; 328 (0x148) for GCN 1.2
Syntax: V_CVT_I32_F32 VDST, SRC0
Description: Convert 32-bit floating point value from SRC0 to signed 32-bit integer, and store result to VDST. Conversion uses rounding to zero. If value is higher/lower than maximal/minimal integer then store MAX_INT32/MIN_INT32 to VDST. If input value is NaN then store 0 to VDST.
Operation:
VDST = 0 if (!ISNAN(ASFLOAT(SRC0))) VDST = (INT32)MAX(MIN(RNDTZINT(ASFLOAT(SRC0)), 2147483647.0), -2147483648.0)

V_CVT_I32_F64

Opcode VOP1: 3 (0x3)
Opcode VOP3A: 387 (0x183) for GCN 1.0/1.1; 323 (0x143) for GCN 1.2
Syntax: V_CVT_I32_F64 VDST, SRC0(2)
Description: Convert 64-bit floating point value from SRC0 to signed 32-bit integer, and store result to VDST. Conversion uses rounding to zero. If value is higher/lower than maximal/minimal integer then store MAX_INT32/MIN_INT32 to VDST. If input value is NaN then store 0 to VDST.
Operation:
VDST = 0 if (!ISNAN(ASDOUBLE(SRC0))) VDST = (INT32)MAX(MIN(RNDTZINT(ASDOUBLE(SRC0)), 2147483647.0), -2147483648.0)

V_CVT_OFF_F32_I4

Opcode VOP1: 14 (0xe)
Opcode VOP3A: 398 (0x18e) for GCN 1.0/1.1; 334 (0x14e) for GCN 1.2
Syntax: V_CVT_OFF_F32_I4 VDST, SRC0
Description: Convert 4-bit signed value from SRC0 to floating point value, normalize that value to range -0.5:0.4375 and store result to VDST.
Operation:
VDST = (FLOAT)((SRC0 & 0xf) ^ 8) / 16.0 - 0.5

V_CVT_RPI_I32_F32

Opcode VOP1: 12 (0xc)
Opcode VOP3A: 396 (0x18c) for GCN 1.0/1.1; 332 (0x14c) for GCN 1.2
Syntax: V_CVT_RPI_I32_F32 VDST, SRC0
Description: Convert 32-bit floating point value from SRC0 to signed 32-bit integer, and store result to VDST. Conversion adds 0.5 to value and rounds negative infinity (floor). If value is higher/lower than maximal/minimal integer then store MAX_INT32/MIN_INT32 to VDST. If input value is NaN/-NaN then store MAX_INT32/MIN_INT32 to VDST.
Operation:
FLOAT SF = ASFLOAT(SRC0) if (!ISNAN(SF)) VDST = (INT32)MAX(MIN(FLOOR(SF + 0.5), 2147483647.0), -2147483648.0) else VDST = (INT32)SF>=0 ? 2147483647 : -2147483648

V_CVT_U32_F32

Opcode VOP1: 7 (0x7)
Opcode VOP3A: 391 (0x187) for GCN 1.0/1.1; 327 (0x147) for GCN 1.2
Syntax: V_CVT_U32_F32 VDST, SRC0
Description: Convert 32-bit floating point value from SRC0 to unsigned 32-bit integer, and store result to VDST. Conversion uses rounding to zero. If value is higher than maximal integer then store MAX_UINT32 to VDST. If input value is NaN then store 0 to VDST.
Operation:
VDST = 0 if (!ISNAN(ASFLOAT(SRC0))) VDST = (UINT32)MIN(RNDTZINT(ASFLOAT(SRC0)), 4294967295.0)

V_CVT_U32_F64

Opcode VOP1: 21 (0x15)
Opcode VOP3A: 405 (0x195) for GCN 1.0/1.1; 341 (0x155) for GCN 1.2
Syntax: V_CVT_U32_F64 VDST, SRC0(2)
Description: Convert 64-bit floating point value from SRC0 to unsigned 32-bit integer, and store result to VDST. Conversion uses rounding to zero. If value is higher than maximal integer then store MAX_UINT32 to VDST. If input value is NaN then store 0 to VDST.
Operation:
VDST = 0 if (!ISNAN(ASDOUBLE(SRC0))) VDST = (UINT32)MIN(RNDTZINT(ASDOUBLE(SRC0)), 4294967295.0)

V_EXP_F32

Opcode VOP1: 37 (0x25) for GCN 1.0/1.1; 32 (0x20) for GCN 1.2
Opcode VOP3A: 421 (0x1a5) for GCN 1.0/1.1; 352 (0x160) for GCN 1.2
Syntax: V_EXP_F32 VDST, SRC0
Description: Approximate power of two from FP value SRC0 and store it to VDST. Instruction for values smaller than -126.0 always returns 0 regardless floatmode in MODE register.
Operation:
if (ASFLOAT(SRC0)>=-126.0) VDST = APPROX_POW2(ASFLOAT(SRC0)) else VDST = 0.0

V_EXP_LEGACY_F32

Opcode VOP1: 70 (0x46) for GCN 1.1; 75 (0x4b) for GCN 1.2
Opcode VOP3A: 454 (0x1c6) for GCN 1.1; 395 (0x18b) for GCN 1.2
Syntax: V_EXP_LEGACY_F32 VDST, SRC0
Description: Approximate power of two from FP value SRC0 and store it to VDST. Instruction for values smaller than -126.0 always returns 0 regardless floatmode in MODE register. For some cases this instructions returns slightly less accurate result than V_EXP_F32.
Operation:
if (ASFLOAT(SRC0)>=-126.0) VDST = APPROX_POW2(ASFLOAT(SRC0)) else VDST = 0.0

V_FFBH_U32

Opcode VOP1: 57 (0x39) for GCN 1.0/1.1; 45 (0x2d) for GCN 1.2
Opcode VOP3A: 441 (0x1b9) for GCN 1.0/1.1; 365 (0x16d) for GCN 1.2
Syntax: V_FFBH_U32 VDST, SRC0
Description: Find last one bit in SRC0. If found, store number of skipped bits to VDST, otherwise set VDST to -1.
Operation:
VDST = -1 for (INT8 i = 31; i >= 0; i--) if ((1U<<i) & SRC0) != 0) { VDST = 31-i; break; }

V_FFBH_I32

Opcode VOP1: 59 (0x3b) for GCN 1.0/1.1; 47 (0x2f) for GCN 1.2
Opcode VOP3A: 443 (0x1bb) for GCN 1.0/1.1; 367 (0x16f) for GCN 1.2
Syntax: V_FFBH_I32 VDST, SRC0
Description: Find last opposite bit to sign in SRC0. If found, store number of skipped bits to VDST, otherwise set VDST to -1.
Operation:
VDST = -1 UINT32 bitval = (INT32)SRC0>=0 ? 1 : 0 for (INT8 i = 31; i >= 0; i--) if ((1U<<i) & SRC0) == (bitval<<i)) { VDST = 31-i; break; }

V_FFBL_B32

Opcode VOP1: 58 (0x3a) for GCN 1.0/1.1; 46 (0x2e) for GCN 1.2
Opcode VOP3A: 442 (0x1ba) for GCN 1.0/1.1; 366 (0x16e) for GCN 1.2
Syntax: V_FFBL_B32 VDST, SRC0
Description: Find first one bit in SRC0. If found, store number of bit to VDST, otherwise set VDST to -1.
Operation:
VDST = -1 for (UINT8 i = 0; i < 32; i++) if ((1U<<i) & SRC0) != 0) { VDST = i; break; }

V_FLOOR_F32

Opcode VOP1: 36 (0x24) for GCN 1.0/1.1; 31 (0x1f) for GCN 1.2
Opcode VOP3A: 420 (0x1a4) for GCN 1.0/1.1; 351 (0x15f) for GCN 1.2
Syntax: V_FLOOR_F32 VDST, SRC0
Description: Truncate floating point value SRC0 with rounding to positive infinity (flooring), and store result to VDST. If SRC0 is infinity or NaN then copy SRC0 to VDST.
Operation:
VDST = FLOOR(ASFLOAT(SRC0))

V_FLOOR_F64

Opcode VOP1: 26 (0x1a) for GCN 1.1/1.2
Opcode VOP3A: 410 (0x19a) for GCN 1.1; 346 (0x15a) for GCN 1.2
Syntax: V_FLOOR_F64 VDST(2), SRC0(2)
Description: Truncate double floating point value SRC0 with rounding to positive infinity (flooring), and store result to VDST. If SRC0 is infinity or NaN then copy SRC0 to VDST.
Operation:
VDST = FLOOR(ASDOUBLE(SRC0))

V_FRACT_F32

Opcode VOP1: 32 (0x20) for GCN 1.0/1.1; 27 (0x1b) for GCN 1.2
Opcode VOP3A: 416 (0x1a0) for GCN 1.0/1.1; 347 (0x15b) for GCN 1.2
Syntax: V_FRACT_F32 VDST, SRC0
Description: Get fractional from floating point value SRC0 and store it to VDST. Fractional will be computed by subtracting floor(SRC0) from SRC0. If SRC0 is infinity or NaN then NaN with proper sign is stored to VDST.
Operation:
FLOAT SF = ASFLOAT(SRC0) if (!ISNAN(SF) && SF!=-INF && SF!=INF) VDST = SF - FLOOR(ASFLOAT(SF)) else VDST = NAN * SIGN(SF)

V_FRACT_F64

Opcode VOP1: 62 (0x3e) for GCN 1.0/1.1; 52 (0x32) for GCN 1.2
Opcode VOP3A: 446 (0x1be) for GCN 1.0/1.1; 372 (0x172) for GCN 1.2
Syntax: V_FRACT_F64 VDST(2), SRC0(2)
Description: Get fractional from double floating point value SRC0 and store it to VDST. Fractional will be computed by subtracting floor(SRC0) from SRC0. If SRC0 is infinity or NaN then NaN with proper sign is stored to VDST.
Operation:
FLOAT SD = ASDOUBLE(SRC0) if (!ISNAN(SD) && SD!=-INF && SD!=INF) VDST = SD - FLOOR(ASDOUBLE(SD)) else VDST = NAN * SIGN(SD)

V_FREXP_EXP_I32_F32

Opcode VOP1: 63 (0x3f) for GCN 1.0/1.1; 51 (0x33) for GCN 1.2
Opcode VOP3A: 447 (0x1bf) for GCN 1.0/1.1; 371 (0x173) for GCN 1.2
Syntax: V_FREXP_EXP_I32_F32 VDST, SRC0
Description: Get exponent plus 1 from single FP value SRC0, and store that exponent to VDST. This instruction realizes frexp function. If SRC0 is infinity or NAN then store -1 to VDST.
Operation:
FLOAT SF = ASFLOAT(SRC0) if (ABS(SF) != INF && !ISNAN(SF)) VDST = FREXP_EXP(SF) else VDST = -1

V_FREXP_EXP_I32_F64

Opcode VOP1: 60 (0x3c) for GCN 1.0/1.1; 48 (0x30) for GCN 1.2
Opcode VOP3A: 444 (0x1bc) for GCN 1.0/1.1; 368 (0x170) for GCN 1.2
Syntax: V_FREXP_EXP_I32_F64 VDST, SRC0(2)
Description: Get exponent plus 1 from double FP value SRC0, and store that exponent to VDST. This instruction realizes frexp function. If SRC0 is infinity or NAN then store -1 to VDST.
Operation:
DOUBLE SD = ASDOUBLE(SRC0) if (ABS(SD) != INF && !ISNAN(SD)) VDST = FREXP_EXP(SD) else VDST = -1

V_FREXP_MANT_F32

Opcode VOP1: 64 (0x40) for GCN 1.0/1.1; 52 (0x34) for GCN 1.2
Opcode VOP3A: 448 (0x1c0) for GCN 1.0/1.1; 372 (0x174) for GCN 1.2
Syntax: V_FREXP_MANT_F32 VDST, SRC0
Description: Get mantisa from double FP value SRC0, and store it to VDST. Mantisa includes sign of input. If SRC0 is infinity then store -NAN to VDST.
Operation:
FLOAT SF = ASFLOAT(SRC0) if (ABS(SF) == INF) VDST = -NAN else if (!ISNAN(SF)) VDST = FREXP_MANT(SF) * SIGN(SF) else VDST = NAN * SIGN(SF)

V_FREXP_MANT_F64

Opcode VOP1: 61 (0x3d) for GCN 1.0/1.1; 49 (0x31) for GCN 1.2
Opcode VOP3A: 445 (0x1bd) for GCN 1.0/1.1; 369 (0x171) for GCN 1.2
Syntax: V_FREXP_MANT_F64 VDST(2), SRC0(2)
Description: Get mantisa from double FP value SRC0, and store it to VDST. Mantisa includes sign of input. If SRC0 is infinity then store -NAN to VDST.
Operation:
DOUBLE SD = ASDOUBLE(SRC0) if (ABS(SD) == INF) VDST = -NAN else if (!ISNAN(SD)) VDST = FREXP_MANT(SD) * SIGN(SD) else VDST = NAN * SIGN(SD)

V_LOG_CLAMP_F32

Opcode VOP1: 38 (0x26) for GCN 1.0/1.1
Opcode VOP3A: 422 (0x1a6) for GCN 1.0/1.1
Syntax: V_LOG_CLAMP_F32 VDST, SRC0
Description: Approximate logarithm of base 2 from floating point value SRC0 with clamping infinities to -MAX_FLOAT. Result is stored in VDST. If SRC0 is negative then store -NaN to VDST. This instruction doesn't handle denormalized values regardless FLOAT MODE register setup.
Operation:
FLOAT F = ASFLOAT(SRC0) if (F==1.0) VDST = 0.0f if (F<0.0) VDST = -NaN else { VDST = APPROX_LOG2(F) if (ASFLOAT(VDST)==-INF) VDST = -MAX_FLOAT }

V_LOG_F32

Opcode VOP1: 39 (0x27) for GCN 1.0/1.1; 33 (0x21) for GCN 1.2
Opcode VOP3A: 423 (0x1a7) for GCN 1.0/1.1; 353 (0x161) for GCN 1.2
Syntax: V_LOG_F32 VDST, SRC0
Description: Approximate logarithm of base 2 from floating point value SRC0, and store result to VDST. If SRC0 is negative then store -NaN to VDST. This instruction doesn't handle denormalized values regardless FLOAT MODE register setup.
Operation:
FLOAT F = ASFLOAT(SRC0) if (F==1.0) VDST = 0.0f if (F<0.0) VDST = -NaN else VDST = APPROX_LOG2(F)

V_LOG_LEGACY_F32

Opcode VOP1: 69 (0x45) for GCN 1.1; 76 (0x4c) for GCN 1.2
Opcode VOP3A: 453 (0x1c5) for GCN 1.1; 396 (0x18c) for GCN 1.2
Syntax: V_LOG_LEGACY_F32 VDST, SRC0
Description: Approximate logarithm of base 2 from floating point value SRC0, and store result to VDST. If SRC0 is negative then store -NaN to VDST. This instruction doesn't handle denormalized values regardless FLOAT MODE register setup. This instruction returns slightly different results than V_LOG_F32.
Operation:
FLOAT F = ASFLOAT(SRC0) if (F==1.0) VDST = 0.0f if (F<0.0) VDST = -NaN else VDST = APPROX_LOG2(F)

V_MOV_B32

Opcode VOP1: 1 (0x1)
Opcode VOP3A: 385 (0x181) for GCN 1.0/1.1; 321 (0x141) for GCN 1.2
Syntax: V_MOV_B32 VDST, SRC0
Description: Move SRC0 into VDST.
Operation:
VDST = SRC0

V_MOV_FED_B32

Opcode VOP1: 9 (0x9)
Opcode VOP3A: 393 (0x189) for GCN 1.0/1.1; 329 (0x149) for GCN 1.2
Syntax: V_MOV_FED_B32 VDST, SRC0
Description: Introduce edc double error upon write to dest vgpr without causing an exception (???).

V_MOVRELD_B32

Opcode VOP1: 66 (0x42) for GCN 1.0/1.1; 54 (0x34) for GCN 1.2
Opcode VOP3A: 450 (0x1c2) for GCN 1.0/1.1; 374 (0x174) for GCN 1.2
Syntax: V_MOVRELD_B32 VDST, VSRC0
Description: Move SRC0 to VGPR[VDST_NUMBER+M0].
Operation:
VGPR[VDST_NUMBER+M0] = SRC0

V_MOVRELS_B32

Opcode VOP1: 67 (0x43) for GCN 1.0/1.1; 55 (0x35) for GCN 1.2
Opcode VOP3A: 451 (0x1c3) for GCN 1.0/1.1; 375 (0x175) for GCN 1.2
Syntax: V_MOVRELS_B32 VDST, VSRC0
Description: Move SRC0[SRC0_NUMBER+M0] to VDST.
Operation:
VDST = VGPR[SRC0_NUMBER+M0]

V_MOVRELSD_B32

Opcode VOP1: 68 (0x44) for GCN 1.0/1.1; 56 (0x36) for GCN 1.2
Opcode VOP3A: 452 (0x1c4) for GCN 1.0/1.1; 376 (0x176) for GCN 1.2
Syntax: V_MOVRELSD_B32 VDST, VSRC0
Description: Move SRC0[SRC0_NUMBER+M0] to VGPR[VDST_NUMBER+M0].
Operation:
VGPR[VDST_NUMBER+M0] = VGPR[SRC0_NUMBER+M0]

V_NOP

Opcode VOP1: 0 (0x0)
Opcode VOP3A: 384 (0x180) for GCN 1.0/1.1; 320 (0x140) for GCN 1.2
Syntax: V_NOP
Description: Do nothing.

V_NOT_B32

Opcode VOP1: 55 (0x37) for GCN 1.0/1.1; 43 (0x2b) for GCN 1.2
Opcode VOP3A: 439 (0x1b7) for GCN 1.0/1.1; 363 (0x16b) for GCN 1.2
Syntax: V_NOT_B32 VDST, SRC0
Description: Do bitwise negation on 32-bit SRC0, and store result to VDST.
Operation:
VDST = ~SRC0

V_RCP_CLAMP_F32

Opcode VOP1: 40 (0x28) for GCN 1.0/1.1
Opcode VOP3A: 424 (0x1a8) for GCN 1.0/1.1
Syntax: V_RCP_CLAMP_F32 VDST, SRC0
Description: Approximate reciprocal from floating point value SRC0 and store it to VDST. Guaranted error below 1ulp. Result is clamped to MAX_FLOAT including sign of a result.
Operation:
VDST = APPROX_RCP(ASFLOAT(SRC0)) if (ABS(ASFLOAT(VDST))==INF) VDST = SIGN(ASFLOAT(VDST)) * MAX_FLOAT

V_RCP_CLAMP_F64

Opcode VOP1: 48 (0x30) for GCN 1.0/1.1
Opcode VOP3A: 432 (0x1b0) for GCN 1.0/1.1
Syntax: V_RCP_CLAMP_F64 VDST(2), SRC0(2)
Description: Approximate reciprocal from double FP value SRC0 and store it to VDST. Relative error of approximation is ~1e-8. Result is clamped to MAX_DOUBLE value including sign of a result.
Operation:
VDST = APPROX_RCP(ASDOUBLE(SRC0)) if (ABS(ASDOUBLE(VDST))==INF) VDST = SIGN(ASDOUBLE(VDST)) * MAX_DOUBLE

V_RCP_F32

Opcode VOP1: 42 (0x2a) for GCN 1.0/1.1; 34 (0x22) for GCN 1.2
Opcode VOP3A: 426 (0x1aa) for GCN 1.0/1.1; 354 (0x162) for GCN 1.2
Syntax: V_RCP_F32 VDST, SRC0
Description: Approximate reciprocal from floating point value SRC0 and store it to VDST. Guaranted error below 1ulp.
Operation:
VDST = APPROX_RCP(ASFLOAT(SRC0))

V_RCP_F64

Opcode VOP1: 47 (0x2f) for GCN 1.0/1.1; 37 (0x25) for GCN 1.2
Opcode VOP3A: 431 (0x1af) for GCN 1.0/1.1; 357 (0x165) for GCN 1.2
Syntax: V_RCP_F64 VDST(2), SRC0(2)
Description: Approximate reciprocal from double FP value SRC0 and store it to VDST. Relative error of approximation is ~1e-8.
Operation:
VDST = APPROX_RCP(ASDOUBLE(SRC0))

V_RCP_IFLAG_F32

Opcode VOP1: 43 (0x2b) for GCN 1.0/1.1; 35 (0x23) for GCN 1.2
Opcode VOP3A: 427 (0x1ab) for GCN 1.0/1.1; 355 (0x163) for GCN 1.2
Syntax: V_RCP_IFLAG_F32 VDST, SRC0
Description: Approximate reciprocal from floating point value SRC0 and store it to VDST. Guaranted error below 1ulp. This instruction signals integer division by zero, instead any floating point exception when error is occurred.
Operation:
VDST = APPROX_RCP_IFLAG(ASFLOAT(SRC0))

V_RCP_LEGACY_F32

Opcode VOP1: 41 (0x29) for GCN 1.0/1.1
Opcode VOP3A: 425 (0x1a9) for GCN 1.0/1.1
Syntax: V_RCP_LEGACY_F32 VDST, SRC0
Description: Approximate reciprocal from floating point value SRC0 and store it to VDST. Guaranted error below 1ulp. If SRC0 or VDST is zero or infinity then store 0 with proper sign to VDST.
Operation:
FLOAT SF = ASFLOAT(SRC0) if (ABS(SF)==0.0) VDST = SIGN(SF)*0.0 else { VDST = APPROX_RCP(SF) if (ABS(ASFLOAT(VDST)) == INF) VDST = SIGN(SF)*0.0 }

V_READFIRSTLANE_B32

Opcode VOP1: 2 (0x2)
Opcode VOP3A: 386 (0x182) for GCN 1.0/1.1; 322 (0x142) for GCN 1.2
Syntax: V_READFIRSTLANE_B32 SDST, VSRC0
Description: Copy one VSRC0 lane value to one SDST. Lane (thread id) is first active lane id or first lane id all lanes are inactive. SSRC1 can be SGPR or M0. Ignores EXEC mask.
Operation:
UINT8 firstlane = 0 for (UINT8 i = 0; i < 64; i++) if ((1ULL<<i) & EXEC) != 0) { firstlane = i; break; } SDST = VSRC0[firstlane]

V_RNDNE_F32

Opcode VOP1: 35 (0x23) for GCN 1.0/1.1; 30 (0x1e) for GCN 1.2
Opcode VOP3A: 420 (0x1a4) for GCN 1.0/1.1; 350 (0x15e) for GCN 1.2
Syntax: V_RNDNE_F32 VDST, SRC0
Description: Round floating point value SRC0 to nearest even integer, and store result to VDST. If SRC0 is infinity or NaN then copy SRC0 to VDST.
Operation:
VDST = RNDNE(ASFLOAT(SRC0))

V_RNDNE_F64

Opcode VOP1: 25 (0x19) for GCN 1.1/1.2
Opcode VOP3A: 409 (0x199) for GCN 1.1; 345 (0x159) for GCN 1.2
Syntax: V_RNDNE_F64 VDST(2), SRC0(2)
Description: Round double floating point value SRC0 to nearest even integer, and store result to VDST. If SRC0 is infinity or NaN then copy SRC0 to VDST.
Operation:
VDST = RNDNE(ASDOUBLE(SRC0))

V_RSQ_CLAMP_F32

Opcode VOP1: 44 (0x2c) for GCN 1.0/1.1
Opcode VOP3A: 428 (0x1ac) for GCN 1.0/1.1
Syntax: V_RSQ_CLAMP_F32 VDST, SRC0
Description: Approximate reciprocal square root from floating point value SRC0 with clamping to MAX_FLOAT, and store result to VDST. If SRC0 is negative value, store -NAN to VDST. This instruction doesn't handle denormalized values regardless FLOAT MODE register setup.
Operation:
VDST = APPROX_RSQRT(ASFLOAT(SRC0)) if (ASFLOAT(VDST)==INF) VDST = MAX_FLOAT

V_RSQ_CLAMP_F64

Opcode VOP1: 50 (0x32) for GCN 1.0/1.1 Opcode VOP3A: 434 (0x1b2) for GCN 1.0/1.1 Syntax: V_RSQ_CLAMP_F64 VDST(2), SRC0(2)
Description: Approximate reciprocal square root from double floating point value SRC0 with clamping to MAX_DOUBLE ,and store it to VDST. If SRC0 is negative value, store -NAN to VDST.
Operation:
VDST = APPROX_RSQRT(ASDOUBLE(SRC0)) if (ASDOUBLE(VDST)==INF) VDST = MAX_DOUBLE

V_RSQ_F32

Opcode VOP1: 46 (0x2e) for GCN 1.0/1.1; 36 (0x24) for GCN 1.2
Opcode VOP3A: 430 (0x1ae) for GCN 1.0/1.1; 356 (0x164) for GCN 1.2
Syntax: V_RSQ_F32 VDST, SRC0
Description: Approximate reciprocal square root from floating point value SRC0 and store it to VDST. If SRC0 is negative value, store -NAN to VDST. This instruction doesn't handle denormalized values regardless FLOAT MODE register setup.
Operation:
VDST = APPROX_RSQRT(ASFLOAT(SRC0))

V_RSQ_F64

Opcode VOP1: 49 (0x31) for GCN 1.0/1.1; 38 (0x26) for GCN 1.2
Opcode VOP3A: 433 (0x1b1) for GCN 1.0/1.1; 358 (0x166) for GCN 1.2
Syntax: V_RSQ_F64 VDST(2), SRC0(2)
Description: Approximate reciprocal square root from double floating point value SRC0 and store it to VDST. If SRC0 is negative value, store -NAN to VDST.
Operation:
VDST = APPROX_RSQRT(ASDOUBLE(SRC0))

V_RSQ_LEGACY_F32

Opcode VOP1: 45 (0x2d) for GCN 1.0/1.1
Opcode VOP3A: 429 (0x1ad) for GCN 1.0/1.1
Syntax: V_RCP_LEGACY_F32 VDST, SRC0
Description: Approximate reciprocal square root from floating point value SRC0, and store result to VDST. If SRC0 is negative value, store -NAN to VDST. If result is zero then store 0.0 to VDST. This instruction doesn't handle denormalized values regardless FLOAT MODE register setup.
Operation:
VDST = APPROX_RSQRT(ASFLOAT(SRC0)) if (ASFLOAT(VDST)==INF) VDST = 0.0

V_SIN_F32

Opcode VOP1: 53 (0x35) for GCN 1.0/1.1; 41 (0x29) for GCN 1.2
Opcode VOP3A: 437 (0x1b5) for GCN 1.0/1.1; 361 (0x169) for GCN 1.2
Syntax: V_SIN_F32 VDST, SRC0
Description: Compute sine of FP value from SRC0. Input value must be normalized to range 1.0 - 1.0 (-360 degree : 360 degree). If SRC0 value is out of range then store 0.0 to VDST. If SRC0 value is infinity, store -NAN to VDST.
Operation:
FLOAT SF = ASFLOAT(SRC0) VDST = 0.0 if (SF >= -1.0 && SF <= 1.0) VDST = APPROX_SIN(SF) else if (ABS(SF)==INF) VDST = -NAN else if (ISNAN(SF)) VDST = SRC0

V_SQRT_F32

Opcode VOP1: 51 (0x33) for GCN 1.0/1.1; 39 (0x27) for GCN 1.2
Opcode VOP3A: 435 (0x1b3) for GCN 1.0/1.1; 359 (0x167) for GCN 1.2
Syntax: V_SQRT_F32 VDST, SRC0
Description: Compute square root of floating point value SRC0, and store result to VDST. If SRC0 is negative value then store -NaN to VDST.
Operation:
if (ASFLOAT(SRC0)>=0.0) VDST = APPROX_SQRT(ASFLOAT(SRC0)) else VDST = -NAN

V_SQRT_F64

Opcode VOP1: 52 (0x34) for GCN 1.0/1.1; 40 (0x28) for GCN 1.2
Opcode VOP3A: 436 (0x1b4) for GCN 1.0/1.1; 360 (0x168) for GCN 1.2
Syntax: V_SQRT_F64 VDST(2), SRC0(2)
Description: Compute square root of double floating point value SRC0, and store result to VDST. Relative error of approximation is ~1e-8. If SRC0 is negative value then store -NaN to VDST.
Operation:
if (ASDOUBLE(SRC0)>=0.0) VDST = APPROX_SQRT(ASDOUBLE(SRC0)) else VDST = -NAN

V_TRUNC_F32

Opcode VOP1: 33 (0x21) for GCN 1.0/1.1; 28 (0x1c) for GCN 1.2
Opcode VOP3A: 417 (0x1a1) for GCN 1.0/1.1; 348 (0x15c) for GCN 1.2
Syntax: V_TRUNC_F32 VDST, SRC0
Description: Get integer value from floating point value SRC0, and store (as float) it to VDST. If SRC0 is infinity or NaN then copy SRC0 to VDST.
Operation:
VDST = RNDTZ(ASFLOAT(SRC0))

V_TRUNC_F64

Opcode VOP1: 23 (0x17) for GCN 1.1/1.2
Opcode VOP3A: 407 (0x197) for GCN 1.1; 343 (0x157) for GCN 1.2
Syntax: V_TRUNC_F64 VDST(2), SRC0(2)
Description: Get integer value from double floating point value SRC0, and store (as float) it to VDST. If SRC0 is infinity or NaN then copy SRC0 to VDST.
Operation:
VDST = RNDTZ(ASDOUBLE(SRC0))