From 922fb26f5b0c9959737901db3eb36ac796320661 Mon Sep 17 00:00:00 2001
From: Jacob Trombetta <jacob.trombetta@spaceandtime.io>
Date: Mon, 14 Oct 2024 10:21:08 -0400
Subject: [PATCH] fix: dynamic dory gpu implementation should handle empty sub
 commits

* tests are added to check when there are no sub commits
---
 .../dory/dory_compute_commitments_test.rs     | 30 +++++++++++++++++++
 .../dynamic_dory_commitment_helper_gpu.rs     | 29 ++++++++++++------
 .../dynamic_dory_compute_commitments_test.rs  | 30 +++++++++++++++++++
 3 files changed, 80 insertions(+), 9 deletions(-)

diff --git a/crates/proof-of-sql/src/proof_primitive/dory/dory_compute_commitments_test.rs b/crates/proof-of-sql/src/proof_primitive/dory/dory_compute_commitments_test.rs
index d2b09559b..b5f7a66e2 100644
--- a/crates/proof-of-sql/src/proof_primitive/dory/dory_compute_commitments_test.rs
+++ b/crates/proof-of-sql/src/proof_primitive/dory/dory_compute_commitments_test.rs
@@ -328,6 +328,36 @@ fn we_can_compute_an_empty_dory_commitment() {
     assert_eq!(res[0].0, GT::zero());
     let res = compute_dory_commitments(&[CommittableColumn::BigInt(&[0; 0])], 20, &setup);
     assert_eq!(res[0].0, GT::zero());
+    let res = compute_dory_commitments(
+        &[
+            CommittableColumn::BigInt(&[0; 0]),
+            CommittableColumn::BigInt(&[0; 0]),
+        ],
+        0,
+        &setup,
+    );
+    assert_eq!(res[0].0, GT::zero());
+    assert_eq!(res[1].0, GT::zero());
+    let res = compute_dory_commitments(
+        &[
+            CommittableColumn::BigInt(&[0; 0]),
+            CommittableColumn::BigInt(&[0; 0]),
+        ],
+        5,
+        &setup,
+    );
+    assert_eq!(res[0].0, GT::zero());
+    assert_eq!(res[1].0, GT::zero());
+    let res = compute_dory_commitments(
+        &[
+            CommittableColumn::BigInt(&[0; 0]),
+            CommittableColumn::BigInt(&[0; 0]),
+        ],
+        20,
+        &setup,
+    );
+    assert_eq!(res[0].0, GT::zero());
+    assert_eq!(res[1].0, GT::zero());    
 }
 
 #[test]
diff --git a/crates/proof-of-sql/src/proof_primitive/dory/dynamic_dory_commitment_helper_gpu.rs b/crates/proof-of-sql/src/proof_primitive/dory/dynamic_dory_commitment_helper_gpu.rs
index b0aa4d0df..f6aa6fba2 100644
--- a/crates/proof-of-sql/src/proof_primitive/dory/dynamic_dory_commitment_helper_gpu.rs
+++ b/crates/proof-of-sql/src/proof_primitive/dory/dynamic_dory_commitment_helper_gpu.rs
@@ -291,15 +291,26 @@ pub(super) fn compute_dynamic_dory_commitments(
 
     // Calculate the dynamic Dory commitments.
     let span = span!(Level::INFO, "multi_pairing").entered();
-    let ddc: Vec<DynamicDoryCommitment> = (0..committable_columns.len())
-        .map(|i| {
-            let sub_slice = signed_sub_commits[i..]
-                .iter()
-                .step_by(committable_columns.len())
-                .take(num_commits);
-            DynamicDoryCommitment(pairings::multi_pairing(sub_slice, &Gamma_2[..num_commits]))
-        })
-        .collect();
+    let ddc: Vec<DynamicDoryCommitment> = signed_sub_commits
+        .is_empty()
+        .then_some(vec![
+            DynamicDoryCommitment::default();
+            committable_columns.len()
+        ])
+        .unwrap_or_else(|| {
+            (0..committable_columns.len())
+                .map(|i| {
+                    let sub_slice = signed_sub_commits[i..]
+                        .iter()
+                        .step_by(committable_columns.len())
+                        .take(num_commits);
+                    DynamicDoryCommitment(pairings::multi_pairing(
+                        sub_slice,
+                        &Gamma_2[..num_commits],
+                    ))
+                })
+                .collect()
+        });
     span.exit();
 
     ddc
diff --git a/crates/proof-of-sql/src/proof_primitive/dory/dynamic_dory_compute_commitments_test.rs b/crates/proof-of-sql/src/proof_primitive/dory/dynamic_dory_compute_commitments_test.rs
index b6426efba..20519a74c 100644
--- a/crates/proof-of-sql/src/proof_primitive/dory/dynamic_dory_compute_commitments_test.rs
+++ b/crates/proof-of-sql/src/proof_primitive/dory/dynamic_dory_compute_commitments_test.rs
@@ -185,6 +185,36 @@ fn we_can_compute_an_empty_dynamic_dory_commitment() {
     assert_eq!(res[0].0, GT::zero());
     let res = compute_dynamic_dory_commitments(&[CommittableColumn::BigInt(&[0; 0])], 20, &setup);
     assert_eq!(res[0].0, GT::zero());
+    let res = compute_dynamic_dory_commitments(
+        &[
+            CommittableColumn::BigInt(&[0; 0]),
+            CommittableColumn::BigInt(&[0; 0]),
+        ],
+        0,
+        &setup,
+    );
+    assert_eq!(res[0].0, GT::zero());
+    assert_eq!(res[1].0, GT::zero());
+    let res = compute_dynamic_dory_commitments(
+        &[
+            CommittableColumn::BigInt(&[0; 0]),
+            CommittableColumn::BigInt(&[0; 0]),
+        ],
+        5,
+        &setup,
+    );
+    assert_eq!(res[0].0, GT::zero());
+    assert_eq!(res[1].0, GT::zero());
+    let res = compute_dynamic_dory_commitments(
+        &[
+            CommittableColumn::BigInt(&[0; 0]),
+            CommittableColumn::BigInt(&[0; 0]),
+        ],
+        20,
+        &setup,
+    );
+    assert_eq!(res[0].0, GT::zero());
+    assert_eq!(res[1].0, GT::zero());
 }
 
 #[test]