Add ZK opcodes definition

spell-check-custom-words.txt

@@ -271,4 +271,8 @@ OOB
 unspendable
 priori
 padding
-incentivize
+incentivize
+EIPS
+eip
+eips
+ethereum

src/fuel-vm/instruction-set.md

@@ -115,6 +115,8 @@
   - [`ED19`: EdDSA curve25519 verification](#ed19-eddsa-curve25519-verification)
   - [`K256`: keccak-256](#k256-keccak-256)
   - [`S256`: SHA-2-256](#s256-sha-2-256)
+  - [`ECOP`: Elliptic curve operation](#ecop-elliptic-curve-point-operation)
+  - [`EPAR`: Elliptic curve point pairing check](#epar-elliptic-curve-point-pairing-check)
 - [Other Instructions](#other-instructions)
   - [`ECAL`: Call external function](#ecal-call-external-function)
   - [`FLAG`: Set flags](#flag-set-flags)
@@ -2370,6 +2372,58 @@ Panic if:
 - `$rB + $rC` overflows or `> VM_MAX_RAM`
 - The memory range `MEM[$rA, 32]`  does not pass [ownership check](./index.md#ownership)
 
+### `ECOP`: Elliptic curve point operation
+
+|             |                                                     |
+|-------------|-----------------------------------------------------|
+| Description | This opcode regroups all arithmetic operations that can be perform on elliptic curve points. `$rB` defines the curve used. `$rC` defines the type of operation to perform. `$rD` points to the start of the bytes of the operation inputs in memory. `$rA` points to the start of the bytes of the result in memory.                                                   |
+| Operation   | ```MEM[$rA, X] = ecop(MEM[$rD, Y]);```              |
+| Syntax      | `ecop $rA, $rB, $rC, $rD`                           |
+| Encoding    | `0x00 rA rB rC rD`                                  |
+| Notes       | For now, only `$rB` = 0 is accepted                 |
+
+#### Curve ID `$rB` possible values
+
+- `0`: `alt_bn128` elliptic curve.
+
+#### Operation type `$rC` supported
+
+- `0`: two points addition
+- `1`: one point and one scalar multiplication
+
+#### Encoding of points and results by curve ID and operation type
+
+- 1P = one point = (X, Y) = ([32 bytes], [32 bytes])
+- 1S = one scalar = X = [32 bytes]
+
+| `$rB` Curve ID | `$rC` Operation type | `$rA` format         | `$rD` format               |
+|----------------|----------------------|----------------------|----------------------------|
+|    `0`         | `0`                  | `MEM[$rA, 64]` `1P`  | `MEM[$rC, 128]` `1P1P`     |
+|    `0`         | `1`                  | `MEM[$rA, 64]` `1P`  | `MEM[$rC, 96]` `1P1S`      |
+
+### `EPAR`: Elliptic curve point pairing check
+
+|             |                                                     |
+|-------------|-----------------------------------------------------|
+| Description | Perform a specific pairing type within a specific curve both identified by `$rB`. `$rC` defines the number of batch of groups. `$rD` define where the bytes of the groups of points start. `$rA` contains either `0` or `1` as the result of the pairing. |
+| Operation   | ```$rA = epar(MEM[$rD, X * $rC]);```                |
+| Syntax      | `epar $rA, $rB, $rC, $rD`                           |
+| Encoding    | `0x00 rA rB rC rD`                                  |
+| Notes       | For now, only `$rB` = 0 is accepted.                |
+
+<!-- markdownlint-disable-next-line no-duplicate-header -->
+#### Curve/Pairing ID `$rB` possible values
+
+- `0`: optimal ate pairing on `alt_bn128` elliptic curve.
+
+#### Encoding of points by curve ID and check type
+
+- 1P = one point = (X, Y) = ([32 bytes], [32 bytes])
+
+| `$rB` Curve / Pairing ID  | `$rD` format               |
+|---------------------------|----------------------------|
+|    `0`                    | `MEM[$rD, (64 + 64 + 64) * $rC]` Each element is `1P1P1P` (three points coordinates) (192 bytes)   |
+
 ## Other Instructions
 
 All these instructions advance the program counter `$pc` by `4` after performing their operation.