perf: refactor modular add (#4)

Co-authored-by: j1mbo64 <[email protected]>

.github/workflows/cairo.yaml

@@ -15,7 +15,7 @@ jobs:
       - uses: actions/checkout@v4
       - uses: software-mansion/setup-scarb@v1
         with:
-          scarb-version: "2.7.0"
+          scarb-version: "2.8.4"
       - run: scarb fmt --check
       - run: scarb build
       - run: scarb test

Scarb.toml

@@ -2,10 +2,10 @@
 name = "ripemd160"
 description = "RIPEMD-160 hash function"
 version = "0.1.0"
-cairo-version = "2.7.0"
+cairo-version = "2.8.4"
 edition = "2024_07"
 repository = "https://github.com/j1mbo64/ripemd160_cairo"
 keywords = ["hash", "crypto"]
 
 [dev-dependencies]
-cairo_test = "2.7.0"
+cairo_test = "2.8.4"

src/ripemd160.cairo

@@ -216,6 +216,8 @@ fn ripemd160_process_block(ref ctx: RIPEMD160Context, block: @Array<u32>) {
     l5(ref lh2, lh3, ref lh4, lh0, lh1, *block.at(15), 5);
     l5(ref lh1, lh2, ref lh3, lh4, lh0, *block.at(13), 6);
 
+    // Ensure calculation of `left` is kept as local and not as temporary when compiling Sierra to
+    // CASM with `inlining-strategy = "avoid`.
     core::internal::revoke_ap_tracking();
 
     // Right round 1

src/utils.cairo

@@ -1,3 +1,6 @@
+use core::num::traits::OverflowingAdd;
+use core::num::traits::OverflowingMul;
+
 pub(crate) const POW_2_32: u64 = 0x100000000;
 pub(crate) const POW_2_8: u32 = 256;
 
@@ -40,25 +43,26 @@ pub(crate) fn get_pow_2(n: u32) -> u32 {
 }
 
 pub(crate) fn u32_mod_add(a: u32, b: u32) -> u32 {
-    let a: u64 = a.into();
-    let b: u64 = b.into();
-    ((a + b) % POW_2_32).try_into().unwrap()
+    let (res, _) = a.overflowing_add(b);
+    res
 }
 
 pub(crate) fn u32_mod_add_3(a: u32, b: u32, c: u32) -> u32 {
-    let result: u64 = (a.into() + b.into() + c.into()) % POW_2_32;
-    result.try_into().unwrap()
+    let (res, _) = a.overflowing_add(b);
+    let (res, _) = res.overflowing_add(c);
+    res
 }
 
 pub(crate) fn u32_mod_add_4(a: u32, b: u32, c: u32, d: u32) -> u32 {
-    let result: u64 = (a.into() + b.into() + c.into() + d.into()) % POW_2_32;
-    result.try_into().unwrap()
+    let (res, _) = a.overflowing_add(b);
+    let (res, _) = res.overflowing_add(c);
+    let (res, _) = res.overflowing_add(d);
+    res
 }
 
 pub(crate) fn u32_mod_mul(a: u32, b: u32) -> u32 {
-    let a: u64 = a.into();
-    let b: u64 = b.into();
-    ((a * b) % POW_2_32).try_into().unwrap()
+    let (res, _) = a.overflowing_mul(b);
+    res
 }
 
 pub(crate) fn u32_leftrotate(x: u32, n: u32) -> u32 {