Skip to content

Commit

Permalink
feat(avm): add standalone jump opcode (#3781)
Browse files Browse the repository at this point in the history
- Add missing check that program counter advanced in call opcode ( oops
)
    - Moved return storing to intermediate register b 
    - jump dest goes on register a
- Implement trivial jump opcode ( subset of call )
  • Loading branch information
Maddiaa0 committed Jan 2, 2024
1 parent e534204 commit b1b2e7c
Show file tree
Hide file tree
Showing 11 changed files with 289 additions and 231 deletions.
39 changes: 24 additions & 15 deletions barretenberg/cpp/pil/avm/avm_mini.pil
Original file line number Diff line number Diff line change
Expand Up @@ -16,6 +16,7 @@ namespace avmMini(256);

pol commit sel_internal_call;
pol commit sel_internal_return;
pol commit sel_jump;

// Halt program execution
pol commit sel_halt;
Expand Down Expand Up @@ -80,6 +81,7 @@ namespace avmMini(256);

sel_internal_call * (1 - sel_internal_call) = 0;
sel_internal_return * (1 - sel_internal_return) = 0;
sel_jump * (1 - sel_jump) = 0;
sel_halt * (1 - sel_halt) = 0;

op_err * (1 - op_err) = 0;
Expand Down Expand Up @@ -147,33 +149,40 @@ namespace avmMini(256);
// This works in combination with op_div_err * (sel_op_div - 1) = 0;
// Drawback is the need to paralllelize the latter.

//===== CONTROL FLOW =======================================================
//===== JUMP ===============================================================
sel_jump * (pc' - ia) = 0;

//===== CALL_RETURN ========================================================
// The program counter in the next row should be equal to the value loaded from the ia register
// This implies that a load from memory must occur at the same time
// Imply that we must load the return location into mem_idx_a
//===== INTERNAL_CALL ======================================================
// - The program counter in the next row should be equal to the value loaded from the ia register
// - We then write the return location (pc + 1) into the call stack (in memory)

#[RETURN_POINTER_INCREMENT]
sel_internal_call * ( internal_return_ptr' - ( internal_return_ptr + 1)) = 0;
sel_internal_call * ( internal_return_ptr - mem_idx_a) = 0;
sel_internal_call * ((pc + 1) - ia) = 0;

sel_internal_call * (internal_return_ptr' - (internal_return_ptr + 1)) = 0;
sel_internal_call * (internal_return_ptr - mem_idx_b) = 0;
sel_internal_call * (pc' - ia) = 0;
sel_internal_call * ((pc + 1) - ib) = 0;

// TODO(md): Below relations may be removed through sub-op table lookup
sel_internal_call * (rwa - 1) = 0;
sel_internal_call * (mem_op_a - 1) = 0;
sel_internal_call * (rwb - 1) = 0;
sel_internal_call * (mem_op_b - 1) = 0;

// We must load the memory pointer to be the internal_return_ptr
//===== INTERNAL_RETURN ===================================================
// - We load the memory pointer to be the internal_return_ptr
// - Constrain then next program counter to be the loaded value
// - decrement the internal_return_ptr

#[RETURN_POINTER_DECREMENT]
sel_internal_return * ( internal_return_ptr' - ( internal_return_ptr - 1)) = 0;
sel_internal_return * ( (internal_return_ptr - 1) - mem_idx_a) = 0;
sel_internal_return * (internal_return_ptr' - (internal_return_ptr - 1)) = 0;
sel_internal_return * ((internal_return_ptr - 1) - mem_idx_a) = 0;
sel_internal_return * (pc' - ia) = 0;

// TODO(md): Below relations may be removed through sub-op table lookup
sel_internal_return * rwa = 0;
sel_internal_return * (mem_op_a - 1) = 0;

//===== CONTROL_FLOW_CONSISTENCY ============================================
pol CONTROL_FLOW_SELECTORS = (first + sel_internal_call + sel_internal_return + sel_halt);
pol INTERNAL_CALL_STACK_SELECTORS = (first + sel_internal_call + sel_internal_return + sel_halt);
pol OPCODE_SELECTORS = (sel_op_add + sel_op_sub + sel_op_div + sel_op_mul);

// Program counter must increment if not jumping or returning
Expand All @@ -182,7 +191,7 @@ namespace avmMini(256);

// first == 0 && sel_internal_call == 0 && sel_internal_return == 0 && sel_halt == 0 ==> internal_return_ptr == internal_return_ptr'
#[INTERNAL_RETURN_POINTER_CONSISTENCY]
(1 - CONTROL_FLOW_SELECTORS) * (internal_return_ptr' - internal_return_ptr) = 0;
(1 - INTERNAL_CALL_STACK_SELECTORS) * (internal_return_ptr' - internal_return_ptr) = 0;

// TODO: we want to set an initial number for the reserved memory of the jump pointer

Expand Down
68 changes: 0 additions & 68 deletions barretenberg/cpp/pil/avm/avm_mini_opt.pil

This file was deleted.

Original file line number Diff line number Diff line change
Expand Up @@ -36,13 +36,13 @@ class AvmMiniFlavor {
using VerifierCommitmentKey = pcs::VerifierCommitmentKey<Curve>;

static constexpr size_t NUM_PRECOMPUTED_ENTITIES = 2;
static constexpr size_t NUM_WITNESS_ENTITIES = 37;
static constexpr size_t NUM_WITNESS_ENTITIES = 38;
static constexpr size_t NUM_WIRES = NUM_WITNESS_ENTITIES + NUM_PRECOMPUTED_ENTITIES;
// We have two copies of the witness entities, so we subtract the number of fixed ones (they have no shift), one for
// the unshifted and one for the shifted
static constexpr size_t NUM_ALL_ENTITIES = 45;
static constexpr size_t NUM_ALL_ENTITIES = 46;

using Relations = std::tuple<AvmMini_vm::avm_mini<FF>, AvmMini_vm::mem_trace<FF>>;
using Relations = std::tuple<AvmMini_vm::mem_trace<FF>, AvmMini_vm::avm_mini<FF>>;

static constexpr size_t MAX_PARTIAL_RELATION_LENGTH = compute_max_partial_relation_length<Relations>();

Expand Down Expand Up @@ -91,6 +91,7 @@ class AvmMiniFlavor {
avmMini_internal_return_ptr,
avmMini_sel_internal_call,
avmMini_sel_internal_return,
avmMini_sel_jump,
avmMini_sel_halt,
avmMini_sel_op_add,
avmMini_sel_op_sub,
Expand Down Expand Up @@ -131,6 +132,7 @@ class AvmMiniFlavor {
avmMini_internal_return_ptr,
avmMini_sel_internal_call,
avmMini_sel_internal_return,
avmMini_sel_jump,
avmMini_sel_halt,
avmMini_sel_op_add,
avmMini_sel_op_sub,
Expand Down Expand Up @@ -177,6 +179,7 @@ class AvmMiniFlavor {
avmMini_internal_return_ptr,
avmMini_sel_internal_call,
avmMini_sel_internal_return,
avmMini_sel_jump,
avmMini_sel_halt,
avmMini_sel_op_add,
avmMini_sel_op_sub,
Expand All @@ -199,12 +202,12 @@ class AvmMiniFlavor {
avmMini_mem_idx_b,
avmMini_mem_idx_c,
avmMini_last,
avmMini_internal_return_ptr_shift,
avmMini_pc_shift,
memTrace_m_tag_shift,
memTrace_m_val_shift,
memTrace_m_addr_shift,
memTrace_m_tag_shift,
memTrace_m_rw_shift,
memTrace_m_addr_shift)
avmMini_internal_return_ptr_shift,
avmMini_pc_shift)

RefVector<DataType> get_wires()
{
Expand All @@ -225,6 +228,7 @@ class AvmMiniFlavor {
avmMini_internal_return_ptr,
avmMini_sel_internal_call,
avmMini_sel_internal_return,
avmMini_sel_jump,
avmMini_sel_halt,
avmMini_sel_op_add,
avmMini_sel_op_sub,
Expand All @@ -247,12 +251,12 @@ class AvmMiniFlavor {
avmMini_mem_idx_b,
avmMini_mem_idx_c,
avmMini_last,
avmMini_internal_return_ptr_shift,
avmMini_pc_shift,
memTrace_m_tag_shift,
memTrace_m_val_shift,
memTrace_m_addr_shift,
memTrace_m_tag_shift,
memTrace_m_rw_shift,
memTrace_m_addr_shift };
avmMini_internal_return_ptr_shift,
avmMini_pc_shift };
};
RefVector<DataType> get_unshifted()
{
Expand All @@ -273,6 +277,7 @@ class AvmMiniFlavor {
avmMini_internal_return_ptr,
avmMini_sel_internal_call,
avmMini_sel_internal_return,
avmMini_sel_jump,
avmMini_sel_halt,
avmMini_sel_op_add,
avmMini_sel_op_sub,
Expand All @@ -298,18 +303,17 @@ class AvmMiniFlavor {
};
RefVector<DataType> get_to_be_shifted()
{
return {
avmMini_internal_return_ptr, avmMini_pc, memTrace_m_tag, memTrace_m_val, memTrace_m_rw, memTrace_m_addr
};
return { memTrace_m_val, memTrace_m_addr, memTrace_m_tag, memTrace_m_rw, avmMini_internal_return_ptr,
avmMini_pc };
};
RefVector<DataType> get_shifted()
{
return { avmMini_internal_return_ptr_shift,
avmMini_pc_shift,
return { memTrace_m_val_shift,
memTrace_m_addr_shift,
memTrace_m_tag_shift,
memTrace_m_val_shift,
memTrace_m_rw_shift,
memTrace_m_addr_shift };
avmMini_internal_return_ptr_shift,
avmMini_pc_shift };
};
};

Expand All @@ -322,9 +326,8 @@ class AvmMiniFlavor {

RefVector<DataType> get_to_be_shifted()
{
return {
avmMini_internal_return_ptr, avmMini_pc, memTrace_m_tag, memTrace_m_val, memTrace_m_rw, memTrace_m_addr
};
return { memTrace_m_val, memTrace_m_addr, memTrace_m_tag, memTrace_m_rw, avmMini_internal_return_ptr,
avmMini_pc };
};

// The plookup wires that store plookup read data.
Expand Down Expand Up @@ -418,6 +421,7 @@ class AvmMiniFlavor {
Base::avmMini_internal_return_ptr = "AVMMINI_INTERNAL_RETURN_PTR";
Base::avmMini_sel_internal_call = "AVMMINI_SEL_INTERNAL_CALL";
Base::avmMini_sel_internal_return = "AVMMINI_SEL_INTERNAL_RETURN";
Base::avmMini_sel_jump = "AVMMINI_SEL_JUMP";
Base::avmMini_sel_halt = "AVMMINI_SEL_HALT";
Base::avmMini_sel_op_add = "AVMMINI_SEL_OP_ADD";
Base::avmMini_sel_op_sub = "AVMMINI_SEL_OP_SUB";
Expand Down Expand Up @@ -474,6 +478,7 @@ class AvmMiniFlavor {
Commitment avmMini_internal_return_ptr;
Commitment avmMini_sel_internal_call;
Commitment avmMini_sel_internal_return;
Commitment avmMini_sel_jump;
Commitment avmMini_sel_halt;
Commitment avmMini_sel_op_add;
Commitment avmMini_sel_op_sub;
Expand Down Expand Up @@ -530,6 +535,7 @@ class AvmMiniFlavor {
avmMini_internal_return_ptr = deserialize_from_buffer<Commitment>(Transcript::proof_data, num_bytes_read);
avmMini_sel_internal_call = deserialize_from_buffer<Commitment>(Transcript::proof_data, num_bytes_read);
avmMini_sel_internal_return = deserialize_from_buffer<Commitment>(Transcript::proof_data, num_bytes_read);
avmMini_sel_jump = deserialize_from_buffer<Commitment>(Transcript::proof_data, num_bytes_read);
avmMini_sel_halt = deserialize_from_buffer<Commitment>(Transcript::proof_data, num_bytes_read);
avmMini_sel_op_add = deserialize_from_buffer<Commitment>(Transcript::proof_data, num_bytes_read);
avmMini_sel_op_sub = deserialize_from_buffer<Commitment>(Transcript::proof_data, num_bytes_read);
Expand Down Expand Up @@ -590,6 +596,7 @@ class AvmMiniFlavor {
serialize_to_buffer<Commitment>(avmMini_internal_return_ptr, Transcript::proof_data);
serialize_to_buffer<Commitment>(avmMini_sel_internal_call, Transcript::proof_data);
serialize_to_buffer<Commitment>(avmMini_sel_internal_return, Transcript::proof_data);
serialize_to_buffer<Commitment>(avmMini_sel_jump, Transcript::proof_data);
serialize_to_buffer<Commitment>(avmMini_sel_halt, Transcript::proof_data);
serialize_to_buffer<Commitment>(avmMini_sel_op_add, Transcript::proof_data);
serialize_to_buffer<Commitment>(avmMini_sel_op_sub, Transcript::proof_data);
Expand Down
Original file line number Diff line number Diff line change
Expand Up @@ -566,6 +566,30 @@ void AvmMiniTraceBuilder::halt()
});
}

/**
* @brief JUMP OPCODE
* Jumps to a new `jmpDest`
* This function must:
* - Set the next program counter to the provided `jmpDest`.
*
* @param jmpDest - The destination to jump to
*/
void AvmMiniTraceBuilder::jump(uint32_t jmpDest)
{
auto clk = mainTrace.size();

mainTrace.push_back(Row{
.avmMini_clk = clk,
.avmMini_pc = FF(pc),
.avmMini_internal_return_ptr = FF(internal_return_ptr),
.avmMini_sel_jump = FF(1),
.avmMini_ia = FF(jmpDest),
});

// Adjust parameters for the next row
pc = jmpDest;
}

/**
* @brief INTERNAL_CALL OPCODE
* This opcode effectively jumps to a new `jmpDest` and stores the return program counter
Expand All @@ -588,18 +612,19 @@ void AvmMiniTraceBuilder::internal_call(uint32_t jmpDest)
internal_call_stack.push(stored_pc);

// Add the return location to the memory trace
storeInMemTrace(IntermRegister::ia, internal_return_ptr, FF(stored_pc), AvmMemoryTag::ff);
storeInMemTrace(IntermRegister::ib, internal_return_ptr, FF(stored_pc), AvmMemoryTag::ff);
memory.at(internal_return_ptr) = stored_pc;

mainTrace.push_back(Row{
.avmMini_clk = clk,
.avmMini_pc = FF(pc),
.avmMini_internal_return_ptr = FF(internal_return_ptr),
.avmMini_sel_internal_call = FF(1),
.avmMini_ia = stored_pc,
.avmMini_mem_op_a = FF(1),
.avmMini_rwa = FF(1),
.avmMini_mem_idx_a = FF(internal_return_ptr),
.avmMini_ia = FF(jmpDest),
.avmMini_ib = stored_pc,
.avmMini_mem_op_b = FF(1),
.avmMini_rwb = FF(1),
.avmMini_mem_idx_b = FF(internal_return_ptr),
});

// Adjust parameters for the next row
Expand Down
Original file line number Diff line number Diff line change
Expand Up @@ -60,6 +60,9 @@ class AvmMiniTraceBuilder {
void div(uint32_t aOffset, uint32_t bOffset, uint32_t dstOffset, AvmMemoryTag inTag);

// Jump to a given program counter.
void jump(uint32_t jmpDest);

// Jump to a given program counter; storing the return location on a call stack.
// TODO(md): this program counter MUST be an operand to the OPCODE.
void internal_call(uint32_t jmpDest);

Expand Down

0 comments on commit b1b2e7c

Please sign in to comment.