**ISA Comparison Table** - discussion and research at <https://bugs.libre-soc.org/show_bug.cgi?id=893>
-|ISA <br>name |Num <br>opcodes|Num <br>intrinsics|Taxonomy / <br> Class|setvl <br> scalable|Predicate <br> Masks|Twin <br> Predication|Explicit <br> Vector regs|128-bit <br> ops|Bigint |LDST <br> Fault-First|Data-dep<br> Fail-first|Pred-<br> Result|Matrix HW<br> support|
-|--------------|---------------|------------------|---------------------|-------------------|--------------------|---------------------|-------------------------|----------------|--------|---------------------|-----------------------|----------------|---------------------|
-|Draft SVP64 |5 (1) |see (25) |Scalable (2) |yes |yes |yes (3) |no (4) |see (5) |yes (6) |yes (7) |yes (8) |yes (9) |yes (10) |
-|VSX |700+ |700+? (26) |Packed SIMD |no |no |no |yes (12) |yes |no |no |no |no |yes (13) |
-|NEON |~250 (14) |7088 (28) |Packed SIMD |no |no |no |yes |yes |no |no |no |no |no |
-|SVE2 |~1000 (15) |6040 (29) |Predicated SIMD(16) |no (16) |yes |no |yes |yes |no |yes (7) |no |no |yes (33) |
-|AVX512 (17) |~1000s (18) |7256 (30) |Predicated SIMD |no |yes |no |yes |yes |no |no |no |no |no |
-|RVV (19) |~190 (20) |~25000 (31) |Scalable (21) |yes |yes |no |yes |yes (22) |no |yes |no |no |no |
-|Aurora SX(23) |~200 (24) |unknown (32) |Scalable (25) |yes |yes |no |yes |no |no |no |no |no |? |
+|ISA <br>name |Num <br>opcodes|Num <br>intrinsics|Taxonomy / <br> Class|setvl <br> scalable|Predicate <br> Masks|Twin <br> Predication|Explicit <br> Vector regs|128-bit <br> ops|Bigint |LDST <br> Fault-First|Data-dep<br> Fail-first|Pred-<br> Result|Matrix HW<br> support|DCT/FFT HW<br? support |
+|--------------|---------------|------------------|---------------------|-------------------|--------------------|---------------------|-------------------------|----------------|--------|---------------------|-----------------------|----------------|---------------------|-----------------------|
+|Draft SVP64 |5 (1) |see (25) |Scalable (2) |yes |yes |yes (3) |no (4) |see (5) |yes (6) |yes (7) |yes (8) |yes (9) |yes (10) | yes(11) |
+|VSX |700+ |700+? (26) |Packed SIMD |no |no |no |yes (12) |yes |no |no |no |no |yes (13) | no |
+|NEON |~250 (14) |7088 (28) |Packed SIMD |no |no |no |yes |yes |no |no |no |no |no | no |
+|SVE2 |~1000 (15) |6040 (29) |Predicated SIMD(16) |no (16) |yes |no |yes |yes |no |yes (7) |no |no |yes (33) | no |
+|AVX512 (17) |~1000s (18) |7256 (30) |Predicated SIMD |no |yes |no |yes |yes |no |no |no |no |no | no |
+|RVV (19) |~190 (20) |~25000 (31) |Scalable (21) |yes |yes |no |yes |yes (22) |no |yes |no |no |no | no |
+|Aurora SX(23) |~200 (24) |unknown (32) |Scalable (25) |yes |yes |no |yes |no |no |no |no |no |? | no |
* (1): plus EXT001 24-bit prefixing using 25% of EXT001 space. See [[sv/svp64]]
* (2): A 2-Dimensional Scalable Vector ISA **specifically designed for the Power ISA** with both Horizontal-First and Vertical-First Modes. See [[sv/vector_isa_comparison]]
* (7): See [[sv/svp64/appendix]] and [ARM SVE Fault-First](https://alastairreid.github.io/papers/sve-ieee-micro-2017.pdf)
* (8): Based on LD/ST Fail-first, extended to data. See [[sv/svp64/appendix]]
* (9): Turns standard ops into a type of "cmp". See [[sv/svp64/appendix]]
-* (10): Any non-power-of-two Matrices up to 127 FMACs (or other FMA-style op), full triple-loop Schedule. Also DCT (Lee) and FFT Full (RADIX2) Triple-loops supported. See [[sv/remap]]
+* (10): Any non-power-of-two Matrices up to 127 FMACs (or other FMA-style op), full triple-loop Schedule. See [[sv/remap]]
+* (11): DCT (Lee) and FFT Full Triple-loops supported, RADIX2-only. Normally only found in VLIW DSPs (TI MSP30, Qualcom Hexagon). See [[sv/remap]]
* (12): VSX's Vector Registers are mis-named: they are 100% PackedSIMD. AVX-512 is not a Vector ISA either. See [Flynn's Taxonomy](https://en.wikipedia.org/wiki/Flynn%27s_taxonomy)
* (13): Power ISA v3.1 contains "Matrix Multiply Assist" (MMA) which due to PackedSIMD is restricted to RADIX2 and requires inline assembler loop-unrolling for non-power-of-two Matrix dimensions
* (14): difficult to ascertain, see [NEON/VFP](https://developer.arm.com/documentation/den0018/a/NEON-and-VFP-Instruction-Summary/List-of-all-NEON-and-VFP-instructions).